1
|
Wang W, Shehbaz M, Wang X, Du C, Xu D, Shi ZQ, Darwish MA, Qiu HS, Jin BB, Zhou T, Chen YW, Liang QX, Zhang MR, Zhou D. Low-Permittivity and Low-Temperature Cofired BaSO 4-BaF 2 Microwave Dielectric Ceramics for High-Reliability Packaged Electronics. ACS Appl Mater Interfaces 2023. [PMID: 37902771 DOI: 10.1021/acsami.3c13668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2023]
Abstract
In developing low-temperature cofired ceramic (LTCC) technology for high-density packaging or advanced packaged electronics, matching the coefficient of thermal expansion (CTE) among the packaged components is a critical challenge to improve reliability. The CTEs of solders and organic laminates are usually larger than 16.0 ppm of °C1-, while most low-permittivity (εr) dielectric ceramics have CTEs of less than 10.0 ppm °C1-. Therefore, a good CTE match between organic laminates and dielectric ceramics is required for further LTCC applications. In this paper, we propose a high-CTE BaSO4-BaF2 LTCC as a potential solution for high-reliability packaged electronics. The BaSO4-BaF2 ceramics have the advantages of a wide low-temperature sintering range (650-850 °C), low loss, temperature stability, and Ag compatibility, ensuring excellent performance in LTCC technology. The 95 wt %BaSO4-5 wt %BaF2 ceramic has a εr of 9.1, a Q × f of 40,100 GHz @11.03 GHz (Q = 1/tan δ), a temperature coefficient of the resonant frequency of -11.2 ppm °C1-, a CTE of +21.8 ppm °C1-, and a thermal conductivity of 1.3 W mK-1 when sintered at 750 °C. Furthermore, a dielectric resonant antenna using BaSO4-BaF2 ceramics, a typically packaged component of LTCC and laminate, was designed and used to verify the excellent performance by a gain of 6.0 dBi at a central frequency of 8.97 GHz and a high radiation efficiency of 90% over a bandwidth of 760 MHz. Good match and low thermal stress were found in the packaged components of BaSO4-BaF2 ceramics, organic laminates, and Sn-based solders by finite element analysis, proving the potential of this LTCC for high-reliability packaged electronics.
Collapse
Affiliation(s)
- Wei Wang
- Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education & International Center for Dielectric Research, School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi China
| | - Muhammad Shehbaz
- Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education & International Center for Dielectric Research, School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi China
| | - Xin Wang
- Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education & International Center for Dielectric Research, School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi China
| | - Chao Du
- Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education & International Center for Dielectric Research, School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi China
| | - Diming Xu
- Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education & International Center for Dielectric Research, School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi China
| | - Zhong-Qi Shi
- State Key Laboratory for Mechanical Behaviour of Materials, Xi'an Jiaotong University, Xi'an 710049, Shaanxi China
| | - Moustafa Adel Darwish
- Physics Department, Faculty of Science, Tanta University, Al-Geish st., Tanta 31527, Egypt
| | - Hong-Song Qiu
- Research Institute of Superconductor Electronics (RISE), School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, Jiangsu China
| | - Biao-Bing Jin
- Research Institute of Superconductor Electronics (RISE), School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, Jiangsu China
| | - Tao Zhou
- School of Electronic and Information Engineering, Hangzhou Dianzi University, Hangzhou 310018, Zhejiang China
| | - Ya-Wei Chen
- Shenzhen Microgate Technology Co., Ltd., Shenzhen 518118, Guangdong China
| | - Qi-Xin Liang
- Shenzhen Microgate Technology Co., Ltd., Shenzhen 518118, Guangdong China
| | - Mei-Rong Zhang
- Shenzhen Microgate Technology Co., Ltd., Shenzhen 518118, Guangdong China
| | - Di Zhou
- Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education & International Center for Dielectric Research, School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi China
| |
Collapse
|
2
|
Jeong J, Kim S, Yun S, Yang X, Kim YJ. Preparation and Characterization of Low CTE Poly(ethersulfone) Using Lignin Nano Composites as Flexible Substrates. Polymers (Basel) 2023; 15:3113. [PMID: 37514501 PMCID: PMC10383374 DOI: 10.3390/polym15143113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 07/09/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
Polyethersulfone (PES) has outstanding thermal and dimensional stability. It is considered an engineering thermoplastic. However, its high coefficient of thermal expansion (CTE) hinders its use in automobiles, microelectronics, and flexible display areas. To overcome its high coefficient of thermal expansion (CTE), recent studies have focused on reducing its high CTE and improving its mechanical properties by adding nano-sized fillers or materials. The addition of nanofiller or nanofibrils to the PES matrix often has a positive effect on its mechanical and thermal properties, making it a flexible display substrate. To obtain ideal flexible substrates, we prepared polyethersulfone with lignin nanocomposite films to reduce CTE and improve the mechanical and thermal properties of PES by varying the relative ratio of PES in the lignin nanocomposite. In this study, lignin as a biodegradable nanofiller was found to show high thermal, oxidative, and hydrolytic stability with favorable mechanical properties. PES/lignin nanocomposite films were prepared by solution casting according to the content of lignin (0 to 5 wt.%). PES/lignin composite films were subjected to mechanical, thermo-mechanical, optical, and surface analyses. The results showed enhanced thermomechanical and optical properties of PES, with the potential benefits of lignin filler materials realized for the development of thermoplastic polymer blends.
Collapse
Affiliation(s)
- Jieun Jeong
- School of Chemical Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Soochan Kim
- Department of Engineering, University of Cambridge, Cambridge CB3 0FS, UK
| | - Sangsoo Yun
- School of Chemical Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Xin Yang
- Key Laboratory for Light-Weight Materials, Nanjing Tech University, Nanjing 210009, China
| | - Young Jun Kim
- School of Chemical Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| |
Collapse
|
3
|
Backmann V, Dorner F, Drechsler K. An Edge-Filtered Optical Fiber Interrogator for Thermoplastic Polymer Analysis. Sensors (Basel) 2023; 23:3300. [PMID: 36992011 PMCID: PMC10056779 DOI: 10.3390/s23063300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 03/05/2023] [Accepted: 03/15/2023] [Indexed: 06/19/2023]
Abstract
The present paper deals with the determination of thermodynamic quantities of thermoplastic polymers by using an optical fiber interrogator. Typically, laboratory methods such as differential scanning calorimetry (DSC) or thermomechanical analysis (TMA) are a reliable state-of-the-art option for thermal polymer analysis. The related laboratory commodities for such methods are of high cost and are impractical for field applications. In this work, an edge-filter-based optical fiber interrogator, which was originally developed to detect the reflection spectrum of fiber Bragg grating sensors, is utilized for the detection of the boundary reflection intensities of the cleaved end of a standard telecommunication optical fiber (SMF28e). By means of the Fresnel equations, the temperature-dependent refractive index of thermoplastic polymer materials is measured. Demonstrated with the amorphous thermoplastic polymers polyetherimide (PEI) and polyethersulfone (PES), an alternative to DSC and TMA is presented as the glass transition temperatures and coefficients of thermal expansion are derived. A DSC alternative in the semi-crystalline polymer analysis with the absence of a crystal structure is shown as the melting temperature and cooling-rate-dependent crystallization temperatures of polyether ether ketone (PEEK) are detected. The proposed method shows that thermal thermoplastic analysis can be performed with a flexible, low-cost and multipurpose device.
Collapse
|
4
|
Korolev A, Mishnev M, Ulrikh D, Zadorin A. Relaxation Model of the Relations between the Elastic Modulus and Thermal Expansivity of Thermosetting Polymers and FRPs. Polymers (Basel) 2023; 15:polym15030699. [PMID: 36772000 PMCID: PMC9919803 DOI: 10.3390/polym15030699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/22/2023] [Accepted: 01/24/2023] [Indexed: 01/31/2023] Open
Abstract
This research was completed in the development of studies devoted to relations between the elastic modulus (MoE) and thermal expansivity (CTe) of different materials. This study, based on experimental data, confirmed the models of the relations between MoE and CTe under normal and heating temperatures for thermosetting epoxy polymers and glass-fiber FRPs in two variants (unfilled and filled by mineral additives), after the usual glassing and prolonged thermal conditioning (thermo-relaxation). The experiment was based on dilatometric and elastic deformation testing. Two models of MoE/CTe were tested: Barker's model and our authors relaxation model (MoE = f(CTe)), which is based on previous modelling of the non-linearity of the physical properties of polymers' supramolecular structures. The result show that the models' constants depend on composition; Barker's model is applicable only to polymers with satisfying agreement degrees in the range 10-20%; our model is applicable to polymers and FRPs with satisfying agreement degrees in the range of 6-18%.
Collapse
Affiliation(s)
- Alexander Korolev
- Department of Building Construction and Structures, South Ural State University, 454080 Chelyabinsk, Russia
- Correspondence: or (A.K.); (M.M.); (D.U.); Tel.: +7-(922)-750-6508 (A.K.); +7-(999)-585-1936 (M.M.)
| | - Maxim Mishnev
- Department of Building Construction and Structures, South Ural State University, 454080 Chelyabinsk, Russia
- Correspondence: or (A.K.); (M.M.); (D.U.); Tel.: +7-(922)-750-6508 (A.K.); +7-(999)-585-1936 (M.M.)
| | - Dmitrii Ulrikh
- Department of Town Planning, Engineering Systems, and Networks, South Ural State University, 454080 Chelyabinsk, Russia
- Correspondence: or (A.K.); (M.M.); (D.U.); Tel.: +7-(922)-750-6508 (A.K.); +7-(999)-585-1936 (M.M.)
| | - Alexander Zadorin
- Department of Building Construction and Structures, South Ural State University, 454080 Chelyabinsk, Russia
| |
Collapse
|
5
|
Lomov SV, Akmanov IS, Liu Q, Wu Q, Abaimov SG. Negative Temperature Coefficient of Resistance in Aligned CNT Networks: Influence of the Underlying Phenomena. Polymers (Basel) 2023; 15:678. [PMID: 36771980 DOI: 10.3390/polym15030678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/18/2023] [Accepted: 01/19/2023] [Indexed: 02/03/2023] Open
Abstract
Temperature dependence of electrical conductivity/resistivity of CNT networks (dry or impregnated), which is characterised by a temperature coefficient of resistance (TCR), is experimentally observed to be negative, especially for the case of aligned CNT (A-CNT). The paper investigates the role of three phenomena defining the TCR, temperature dependence of the intrinsic conductivity of CNTs, of the tunnelling resistance of their contacts, and thermal expansion of the network, in the temperature range 300-400 K. A-CNT films, created by rolling down A-CNT forests of different length and described in Lee et al., Appl Phys Lett, 2015, 106: 053110, are investigated as an example. The modelling of the electrical conductivity is performed by the nodal analysis of resistance networks, coupled with the finite-element thermomechanical modelling of network thermal expansion. The calculated TCR for the film is about -0.002 1/K and is close to the experimentally observed values. Comparative analysis of the influence of the TCR defining phenomena is performed on the case of dry and impregnated films. The analysis shows that in both cases, for an A-CNT film at the studied temperature interval, the main factor affecting a network's TCR is the TCR of the CNTs themselves. The TCR of the tunnelling contacts plays the secondary role; influence of the film thermal expansion is marginal. The prevailing impact of the intrinsic conductivity TCR on the TCR of the film is explained by long inter-contact segments of CNTs in an A-CNT network, which define the homogenised film conductivity.
Collapse
|
6
|
Wang Y, Liu X, Shen J, Zhao J, Tu G. Synthesis of a Novel Rigid Semi-Alicyclic Dianhydride and Its Copolymerized Transparent Polyimide Films' Properties. Polymers (Basel) 2022; 14:polym14194132. [PMID: 36236080 PMCID: PMC9571554 DOI: 10.3390/polym14194132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 09/27/2022] [Accepted: 09/28/2022] [Indexed: 11/07/2022] Open
Abstract
A new series of colorless polyimides (CPIs) with outstanding thermal properties and mechanical properties were fabricated by the copolymerization of a novel dianhydride and 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) with 2,2′-bistrifluoromethyl benzidine (TFDB). The novel dianhydride, 10-oxo-9-phenyl-9-(trifluoromethyl)-9,10-dihydroanthracene-2,3,6,7-tetraacid dianhydride (3FPODA), possessed a rigid semi-alicyclic structure, –CF3 and phenyl side groups, and an active carbonyl group. Benefitting from the special structure of 3FPODA, the glass transition temperatures (Tg) of the new CPIs improved from 330 °C to 377 °C, the coefficient of thermal expansion (CTE) decreased from 46 ppm/K to 24 ppm/K, and the tensile strength (TS), tensile modulus (TM), and elongation at break (EB) increased from 84 MPa to 136 MPa, 3.2 GPa to 4.4 GPa, and 2.94% to 4.13% with the increasing amount of 3FPODA, respectively. Moreover, the active carbonyl group of the 3FPODA could enhance the CPI’s adhesive properties. These results render the new dianhydride 3FPODA an ideal candidate monomer for the fabrication of high-performance CPIs.
Collapse
|
7
|
Prica CV, Marinca TF, Neamțu BV, Sechel AN, Popa F, Jozsa EM, Chicinaș I. Invar/WC Composite Compacts Obtained by Spark Plasma Sintering from Mechanically Alloyed Powders. Materials (Basel) 2022; 15:6714. [PMID: 36234052 PMCID: PMC9570978 DOI: 10.3390/ma15196714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/21/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
The composite materials are used on an increasingly large scale in top fields, such as the automotive, aerospace, and nuclear industries, due to the combination of the specific properties of the composite components. Invar/WC nanocrystalline composite compacts were successfully obtained by spark plasma sintering from mechanical milled composite powder. The influence of the amount of tungsten carbide (WC) on sintering, coefficient of thermal expansion (CTE), and hardness has been investigated. The relative density and hardness of Invar/WC composite compacts increases with increasing the WC content up to 10 vol.%. At higher amount of WC (15% vol.), the relative density and hardness of the Invar/WC composite compacts decreases. The temperature up to which CTE remains at a low value (0.6-1) × 10-6 °C-1 is influenced by the WC content and decreases with the WC amount of increase.
Collapse
Affiliation(s)
- Călin-Virgiliu Prica
- Materials Science and Engineering Department, Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, 103-106, Muncii Ave, 400641 Cluj-Napoca, Romania
| | - Traian Florin Marinca
- Materials Science and Engineering Department, Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, 103-106, Muncii Ave, 400641 Cluj-Napoca, Romania
| | - Bogdan Viorel Neamțu
- Materials Science and Engineering Department, Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, 103-106, Muncii Ave, 400641 Cluj-Napoca, Romania
| | - Argentina Niculina Sechel
- Materials Science and Engineering Department, Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, 103-106, Muncii Ave, 400641 Cluj-Napoca, Romania
| | - Florin Popa
- Materials Science and Engineering Department, Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, 103-106, Muncii Ave, 400641 Cluj-Napoca, Romania
| | | | - Ionel Chicinaș
- Materials Science and Engineering Department, Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, 103-106, Muncii Ave, 400641 Cluj-Napoca, Romania
| |
Collapse
|
8
|
Moreno-Sanchez D, Sanz de León A, Moreno Nieto D, Delgado FJ, Molina SI. Basalt Fiber Composites with Reduced Thermal Expansion for Additive Manufacturing. Polymers (Basel) 2022; 14:polym14153216. [PMID: 35956730 PMCID: PMC9370959 DOI: 10.3390/polym14153216] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 07/27/2022] [Accepted: 08/05/2022] [Indexed: 11/29/2022] Open
Abstract
Fused filament fabrication (FFF) is gaining attention as an efficient way to create parts and replacements on demand using thermoplastics. This technology requires the development of new materials with a reliable printability that satisfies the requirement of final parts. In this context, a series of composites based on acrylonitrile styrene acrylate (ASA) reinforced with basalt fiber (BF) are reported in this work. First, several surface modification treatments are applied onto the BF to increase their compatibility with the ASA matrix. Then, once the best treatment is identified, the mechanical properties, coefficient of thermal expansion (CTE) and warping distortion of the different specimens designed and prepared by FFF are studied. It was found that the silanized BF is appropriate for an adequate printing, obtaining composites with higher stiffness, tensile strength, low CTE and a significant reduction in part distortion. These composites are of potential interest in the design and manufacturing of final products by FFF, as they show much lower CTE values than pure ASA, which is essential to successfully fabricate large objects using this technique.
Collapse
Affiliation(s)
- Daniel Moreno-Sanchez
- Departamento de Ingeniería Mecánica y Diseño Industrial, Escuela Superior de Ingeniería, IMEYMAT, Universidad de Cádiz, Campus Río San Pedro s/n, 11510 Puerto Real, Spain
- Correspondence:
| | - Alberto Sanz de León
- Departamento de Ciencia de los Materiales e I. M. y Q. I., Facultad de Ciencias, IMEYMAT, Universidad de Cádiz, Campus Río San Pedro s/n, 11510 Puerto Real, Spain
| | - Daniel Moreno Nieto
- Departamento de Ingeniería Mecánica y Diseño Industrial, Escuela Superior de Ingeniería, IMEYMAT, Universidad de Cádiz, Campus Río San Pedro s/n, 11510 Puerto Real, Spain
| | - Francisco J. Delgado
- Departamento de Ciencia de los Materiales e I. M. y Q. I., Facultad de Ciencias, IMEYMAT, Universidad de Cádiz, Campus Río San Pedro s/n, 11510 Puerto Real, Spain
| | - Sergio I. Molina
- Departamento de Ciencia de los Materiales e I. M. y Q. I., Facultad de Ciencias, IMEYMAT, Universidad de Cádiz, Campus Río San Pedro s/n, 11510 Puerto Real, Spain
| |
Collapse
|
9
|
Rodrigues LM, Marinkovic BA. Effects of Fused Silica Addition on Thermal Expansion, Density, and Hardness of Alumix-231 Based Composites. Materials (Basel) 2022; 15:3476. [PMID: 35629504 DOI: 10.3390/ma15103476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/06/2022] [Accepted: 05/09/2022] [Indexed: 12/10/2022]
Abstract
Fused silica is a ceramic with promising applications as a filler in composites due to its near-zero thermal expansion. Substitution of heavy cast iron with Al-based light alloys is of utmost importance for the automotive industry. However, the high thermal expansion of Al alloys is an obstacle to their use in some applications. As such, ceramic fillers are natural candidates for tuning thermal expansion of Al-based matrices, due to their inherently moderate or low thermal expansion. Alumix-231 is a new promising alloy, and fused silica has never been used before to lower its thermal expansion. Composites with the addition of 5 to 20 vol.% of fused silica were developed through powder metallurgy, and the best results in terms of reduction of thermal expansion were reached after liquid phase sintering at 565 °C. Coefficients of thermal expansion as low as 13.70 and 12.73 × 10−6 °C−1 (between 25 and 400 °C) were reached for the addition of 15 and 20 vol.% of fused silica, a reduction of 29.9% and 34.8%, respectively, in comparison to neat Alumix-231. In addition, the density and hardness of these composites were not significantly affected, since they suffered only a small decrease, no higher than 6% and 5%, respectively. As such, the obtained results showed that Alumix-231/fused silica composites are promising materials for automotive applications.
Collapse
|
10
|
Huang L, Zhou Y, Guo T, Han D, Gu Y, Song C, Pan F. Investigation of Temperature-Dependent Magnetic Properties and Coefficient of Thermal Expansion in Invar Alloys. Materials (Basel) 2022; 15:1504. [PMID: 35208043 DOI: 10.3390/ma15041504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 02/09/2022] [Accepted: 02/15/2022] [Indexed: 11/17/2022]
Abstract
Invar Fe–Ni alloy is a prominent Ni steel alloy with a low coefficient of thermal expansion around room temperature. We investigate the correlation between magnetic properties and thermal expansion in cold-drawn Fe–36Ni wires with different heat treatment conditions, where the annealing parameters with furnace cooling (cooling from the annealing temperature of 300, 400, 500, 600, 700, 800, 900, and 1000 °C) are used. The variation trend of magnetic properties is consistent with that of thermal expansion for all samples, where the maximum appears at 600 °C -treated sample and 400 °C shows the minimum. The domain size and the area of domain walls determine the total energy of the domain wall, and the total energy directly determines the size of magnetostriction, which is closely related to the coefficient of thermal expansion. Also, the differential thermal analysis (DTA) shows endothermic and exothermic reactions represent crystalline transitions, which could possibly cause the abrupt change of magnetic properties and thermal expansion coefficient of materials. The results indicate that there is a certain relation between thermal expansion and magnetic properties. Besides the fundamental significance, our work provides an Invar alloy with a low coefficient of thermal expansion for practical use.
Collapse
|
11
|
Faust JL, Kelly PG, Jones BD, Roy-Mayhew JD. Effects of Coefficient of Thermal Expansion and Moisture Absorption on the Dimensional Accuracy of Carbon-Reinforced 3D Printed Parts. Polymers (Basel) 2021; 13:3637. [PMID: 34771194 DOI: 10.3390/polym13213637] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/14/2021] [Accepted: 10/19/2021] [Indexed: 11/17/2022] Open
Abstract
Environmental effects—temperature and moisture—on 3D printed part dimensional accuracy are explored. The coefficient of thermal expansion of four different nylon materials was determined for XY and ZX print orientations, with 0°, 45°/−45°, and 90° infill patterns. Unreinforced nylon exhibited a thermal expansion coefficient of the same order regardless of condition (from 11.4 to 17.5 × 10−5 1/°C), while nylons reinforced with discontinuous carbon fiber were highly anisotropic, for instance exhibiting 2.2 × 10−5 1/°C in the flow direction (0° infill angle) and 24.8 × 10−5 1/°C in the ZX orientation. The temperature profile of a part during printing is shown, demonstrating a build steady state temperature of ~ 35 °C. The effect of moisture uptake by the part was also explored, with dimensional changes of ~0.5–1.5% seen depending on feature, with height expanding the most. The effects of moisture were significantly reduced for large flat parts with the inclusion of continuous fiber reinforcement throughout the part.
Collapse
|
12
|
Shardakov IN, Trufanov AN. Identification of the Temperature Dependence of the Thermal Expansion Coefficient of Polymers. Polymers (Basel) 2021; 13:3035. [PMID: 34577938 DOI: 10.3390/polym13183035] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 08/26/2021] [Accepted: 09/02/2021] [Indexed: 11/23/2022] Open
Abstract
In this paper, we proposed an approach to study the strain response of polymer film samples under various temperature effects and note their corresponding effects. The advantages of the developed approach are determined by the fact that thin films of material are used as samples where it is possible to generate a sufficiently uniform temperature field in a wide range of temperature change rates. A dynamic mechanical analyzer was used for the experimental implementation of the above approach for two UV-curable polymers and one type of epoxy resin. Experimental results have shown that the thermal expansion coefficients for these polymers depend significantly not only on the temperature but also on its change rate. The strain response of the polymer to heating and cooling, with the same absolute values of the rate of temperature change, differs significantly, and this dissimilarity becomes stronger with its increasing. The results of thermomechanical experiments for massive samples on traditional dilatometer are shown to compare with the results for film samples. The discovered dependences of the temperature expansion coefficient on the temperature and its change rate can be used for mathematical modeling of thermomechanical processes arising during the operation of products made of polymers.
Collapse
|
13
|
Zhou H, Li Y, Wang H, Ran M, Tong Z, Zhang W, Liu J, Zheng W. Fabrication of Functionally Graded Diamond/Al Composites by Liquid-Solid Separation Technology. Materials (Basel) 2021; 14:3205. [PMID: 34200780 DOI: 10.3390/ma14123205] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/04/2021] [Accepted: 06/08/2021] [Indexed: 11/17/2022]
Abstract
The electronic packaging shell, the necessary material for hermetic packaging of large microelectronic device chips, is made by mechanical processing of a uniform block. However, the property variety requirements at different positions of the shell due to the performance have not been solved. An independently developed liquid-solid separation technology is applied to fabricate the diamond/Al composites with a graded distribution of diamond particles. The diamond content decreases along a gradient from the bottom of the shell, which houses the chips, to the top of the shell wall, which is welded with the cover plate. The bottom of the shell has a thermal conductivity (TC) of 169 W/mK, coefficient of thermal expansion (CTE) of 11.0 × 10-6/K, bending strength of 88 MPa, and diamond content of 48 vol.%. The top of the shell has a TC of 108 W/mK, CTE of 19.3 × 10-6/K, bending strength of 175 MPa, and diamond content of 15 vol.%, which solves the special requirements of different parts of the shell and helps to improve the thermal stability of packaging components. Moreover, the interfacial characteristics are also investigated. This work provides a promising approach for the preparation of packaging shells by near-net shape forming.
Collapse
|
14
|
Švec M, Vodičková V, Hanus P, Pazourková Prokopčáková P, Čamek L, Moravec J. Effect of Higher Silicon Content and Heat Treatment on Structure Evolution and High-Temperature Behaviour of Fe-28Al-15Si-2Mo Alloy. Materials (Basel) 2021; 14:3031. [PMID: 34199604 DOI: 10.3390/ma14113031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 05/26/2021] [Accepted: 05/29/2021] [Indexed: 11/29/2022]
Abstract
This paper describes the structure and properties of cast Fe3Al-based alloy doped with 15 at. % of silicon and 2 at. % of molybdenum. The higher content of silicon is useful for the enhancement of high-temperature mechanical properties or corrosion resistance of iron aluminides but deteriorates their workability due to increased brittleness. It was found that the presence of both alloying elements leads to an increase of values of the high-temperature yield stress in compression. The heat treatment (annealing at 800 °C for 100 h) used for the achievement of phase stability causes the grain coarsening, so the values of the high-temperature yield stress in compression are lower at 600 °C and 700 °C in comparison to values measured for the as-cast state. This stabilization annealing significantly improves the workability/machinability of alloy. Furthermore, the higher silicon content positively affects the values of the thermal expansion coefficient that was found to be lower in the temperature range up to 600 °C compared to alloys with lower content of silicon.
Collapse
|
15
|
Gupta A, Tas B, Korbmacher D, Dutta B, Neitzel Y, Grabowski B, Hickel T, Esin V, Divinski SV, Wilde G, Neugebauer J. A Combined Experimental and First-Principles Based Assessment of Finite-Temperature Thermodynamic Properties of Intermetallic Al 3Sc. Materials (Basel) 2021; 14:1837. [PMID: 33917269 DOI: 10.3390/ma14081837] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/15/2021] [Accepted: 03/24/2021] [Indexed: 11/17/2022]
Abstract
We present a first-principles assessment of the finite-temperature thermodynamic properties of the intermetallic Al3Sc phase including the complete spectrum of excitations and compare the theoretical findings with our dilatometric and calorimetric measurements. While significant electronic contributions to the heat capacity and thermal expansion are observed near the melting temperature, anharmonic contributions, and electron-phonon coupling effects are found to be relatively small. On the one hand, these accurate methods are used to demonstrate shortcomings of empirical predictions of phase stabilities such as the Neumann-Kopp rule. On the other hand, their combination with elasticity theory was found to provide an upper limit for the size of Al3Sc nanoprecipitates needed to maintain coherency with the host matrix. The chemo-mechanical coupling being responsible for the coherency loss of strengthening precipitates is revealed by a combination of state-of-the-art simulations and dedicated experiments. These findings can be exploited to fine-tune the microstructure of Al-Sc-based alloys to approach optimum mechanical properties.
Collapse
|
16
|
Gupta NS, Lee KS, Labouriau A. Tuning Thermal and Mechanical Properties of Polydimethylsiloxane with Carbon Fibers. Polymers (Basel) 2021; 13:1141. [PMID: 33918388 PMCID: PMC8038219 DOI: 10.3390/polym13071141] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 04/01/2021] [Accepted: 04/01/2021] [Indexed: 02/08/2023] Open
Abstract
In order to meet the needs of constantly advancing technologies, fabricating materials with improved properties and predictable behavior has become vital. To that end, we have prepared polydimethylsiloxane (PDMS) polymer samples filled with carbon nanofibers (CFs) at 0, 0.5, 1.0, 2.0, and 4.0 CF loadings (w/w) to investigate and optimize the amount of filler needed for fabrication with improved mechanical properties. Samples were prepared using easy, cost-efficient mechanical mixing to combine the PDMS and CF filler and were then characterized by chemical (FTIR), mechanical (hardness and tension), and physical (swelling, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and coefficient of thermal expansion) analyses to determine the material properties. We found that hardness and thermal stability increased predictably, while the ultimate strength and toughness both decreased. Repeated tension caused the CF-filled PDMS samples to lose significant toughness with increasing CF loadings. The hardness and thermal degradation temperature with 4 wt.% CF loading in PDMS increased more than 40% and 25 °C, respectively, compared with the pristine PDMS sample. Additionally, dilatometer measurements showed a 20% decrease in the coefficient of thermal expansion (CTE) with a small amount of CF filler in PDMS. In this study, we were able to show the mechanical and thermal properties of PDMS can be tuned with good confidence using CFs.
Collapse
Affiliation(s)
| | | | - Andrea Labouriau
- C-CDE Chemical Diagnostics and Engineering, Los Alamos National Laboratory, Los Alamos, NM 87545, USA;
| |
Collapse
|
17
|
Makarov I, Vinogradov M, Mironova M, Shandryuk G, Golubev Y, Berkovich A. The Thermal Behavior of Lyocell Fibers Containing Bis(trimethylsilyl)acetylene. Polymers (Basel) 2021; 13:polym13040537. [PMID: 33670430 PMCID: PMC7918831 DOI: 10.3390/polym13040537] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/05/2021] [Accepted: 02/08/2021] [Indexed: 11/16/2022] Open
Abstract
This study focuses on the preparation of carbon fiber precursors from solutions of cellulose in N-methylmorpholine-N-oxide with the addition of bis(trimethylsilyl)acetylene, studying their structural features and evaluating thermal behavior. The introduction of a silicon-containing additive into cellulose leads to an increase in the carbon yield during carbonization of composite precursors. The type of the observed peaks on the differential scanning calorimetry (DSC) curves cardinally changes from endo peaks intrinsic for cellulose fibers to the combination of endo and exo peaks for composite fibers. For the first time, coefficient of thermal expansion (CTE) values were obtained for Lyocell fibers and composite fibers with bis(trimethylsilyl)acetylene (BTMSA). The study of the dependence of linear dimensions of the heat treatment fibers on temperature made it possible to determine the relation between thermal expansion coefficients of carbonized fibers and thermogravimetric curves, as well as to reveal the relationship between fiber shrinkage and BTMSA bis(trimethylsilyl)acetylene content. Carbon fibers from composite precursors are obtained at a processing temperature of 1200 °C. A study of the structure of carbon fibers by X-ray diffraction, Raman spectroscopy, and transmission electron microscopy made it possible to determine the amorphous structure of the fibers obtained.
Collapse
Affiliation(s)
- Igor Makarov
- A.V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 29 Leninsky prospect, 119991 Moscow, Russia; (M.V.); (G.S.)
- Correspondence: (I.M.); (M.M.); Tel.: +74-956-475-927 (ext. 233) (M.M.)
| | - Markel Vinogradov
- A.V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 29 Leninsky prospect, 119991 Moscow, Russia; (M.V.); (G.S.)
| | - Maria Mironova
- A.V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 29 Leninsky prospect, 119991 Moscow, Russia; (M.V.); (G.S.)
- Correspondence: (I.M.); (M.M.); Tel.: +74-956-475-927 (ext. 233) (M.M.)
| | - Georgy Shandryuk
- A.V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 29 Leninsky prospect, 119991 Moscow, Russia; (M.V.); (G.S.)
| | - Yaroslav Golubev
- Chemical Department, M.V. Lomonosov Moscow State University, 1 Leninskiye Gory, 119991 Moscow, Russia; (Y.G.); (A.B.)
| | - Anna Berkovich
- Chemical Department, M.V. Lomonosov Moscow State University, 1 Leninskiye Gory, 119991 Moscow, Russia; (Y.G.); (A.B.)
| |
Collapse
|
18
|
Fu K, Yang J, Cao C, Zhai Q, Qiao W, Qiao J, Gao H, Zhou Z, Ji J, Li M, Liu C, Wang B, Bai W, Duan H, Xue Y, Tang C. Highly Multifunctional and Thermoconductive Performances of Densely Filled Boron Nitride Nanosheets/Epoxy Resin Bulk Composites. ACS Appl Mater Interfaces 2021; 13:2853-2867. [PMID: 33412856 DOI: 10.1021/acsami.0c19977] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In the development of hexagonal boron nitride (h-BN)-based polymeric composites with high thermal conductivity, it is always challenging to achieve a dense filling of h-BN fillers to form a desired high-density thermal transfer network. Here, a series of boron nitride nanosheets (BNNSs)/epoxy resin (EP) bulk composites filled with ultrahigh BNNSs content (65-95 wt %) is successfully constructed through a well-designed mechanical-balling prereaction combined with a general pressure molding method. By means of this method, the highly filled BNNSs fillers are uniformly dispersed and strongly bonded with EP within the composites. As a result, the densely BNNSs-filled composites can exhibit multiple performances. They have excellent mechanical properties, and their maximum compression strength is 30-97 MPa. For a BNNSs/EP composite with filling ultrahigh BNNSs fraction up to 90 wt %, its highly in-plane thermal conductivities (TC) are 6.7 ± 0.1 W m-1 K-1 (at 25 °C) to 8.7 ± 0.2 W m-1 K-1 (200 °C), respectively. In addition, the minimum coefficient of thermal expansion of BNNSs/EP composites is 4.5 ± 1.3 ppm/°C (only ∼4% of that of the neat EP), while their dielectric constants are basically located between 3-4 along with their dielectric loss tangent values exceptionally <0.3 in the ultrahigh frequency range of 12-40 GHz. Additionally, these BNNSs/EP composites exhibit remarkable cycle stability in heat transfer during heating and cooling processes because of their structural robustness. Thus, this type of densely BNNSs-filled BNNSs/EP composite would have great potential for further practical thermal management fields.
Collapse
Affiliation(s)
- Kun Fu
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Jingwen Yang
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Chaochao Cao
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Qinghong Zhai
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Wei Qiao
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Jiaxiao Qiao
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Hejun Gao
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Zheng Zhou
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Jiawei Ji
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Mengyuan Li
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Chaoze Liu
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Bozheng Wang
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Wenjuan Bai
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Hongliang Duan
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Yanming Xue
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| | - Chengchun Tang
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, P. R. China
- Hebei Key Laboratory of Boron Nitride Micro and Nano Materials, Hebei University of Technology, Tianjin 300130, P.R. China
| |
Collapse
|
19
|
Gurauskis D, Kilikevičius A, Kasparaitis A. Thermal and Geometric Error Compensation Approach for an Optical Linear Encoder. Sensors (Basel) 2021; 21:E360. [PMID: 33430333 DOI: 10.3390/s21020360] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 12/24/2020] [Accepted: 01/05/2021] [Indexed: 11/17/2022]
Abstract
Linear displacement measuring systems, like optical encoders, are widely used in various precise positioning applications to form a full closed-loop control system. Thus, the performance of the machine and the quality of its technological process are highly dependent on the accuracy of the linear encoder used. Thermoelastic deformation caused by a various thermal sources and the changing ambient temperature are important factors that introduce errors in an encoder reading. This work presents an experimental realization of the real-time geometric and thermal error compensation of the optical linear encoder. The implemented compensation model is based on the approximation of the tested encoder error by a simple parametric function and calculation of a linear nature error component according to an ambient temperature variation. The calculation of a two-dimensional compensation function and the real-time correction of the investigated linear encoder position readings are realized by using a field programmable gate array (FPGA) computing platform. The results of the performed experimental research verified that the final positioning error could be reduced up to 98%.
Collapse
|
20
|
Lee Sanchez WA, Huang CY, Chen JX, Soong YC, Chan YN, Chiou KC, Lee TM, Cheng CC, Chiu CW. Enhanced Thermal Conductivity of Epoxy Composites Filled with Al 2O 3/Boron Nitride Hybrids for Underfill Encapsulation Materials. Polymers (Basel) 2021; 13:E147. [PMID: 33401420 PMCID: PMC7795928 DOI: 10.3390/polym13010147] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 12/29/2020] [Accepted: 12/29/2020] [Indexed: 11/21/2022] Open
Abstract
In this study, a thermal conductivity of 0.22 W·m-1·K-1 was obtained for pristine epoxy (EP), and the impact of a hybrid filler composed of two-dimensional (2D) flake-like boron nitride (BN) and zero-dimensional (0D) spherical micro-sized aluminum oxide (Al2O3) on the thermal conductivity of epoxy resin was investigated. With 80 wt.% hybrid Al2O3-BN filler contents, the thermal conductivity of the EP composite reached 1.72 W·m-1·K-1, increasing approximately 7.8-fold with respect to the pure epoxy matrix. Furthermore, different important properties for the application were analyzed, such as Fourier-transform infrared (FTIR) spectra, viscosity, morphology, coefficient of thermal expansion (CTE), glass transition temperature (Tg), decomposition temperature (Td), dielectric properties, and thermal infrared images. The obtained thermal performance is suitable for specific electronic applications such as flip-chip underfill packaging.
Collapse
Affiliation(s)
- William Anderson Lee Sanchez
- Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan; (W.A.L.S.); (C.-Y.H.); (J.-X.C.); (Y.-C.S.)
| | - Chen-Yang Huang
- Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan; (W.A.L.S.); (C.-Y.H.); (J.-X.C.); (Y.-C.S.)
| | - Jian-Xun Chen
- Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan; (W.A.L.S.); (C.-Y.H.); (J.-X.C.); (Y.-C.S.)
| | - Yu-Chian Soong
- Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan; (W.A.L.S.); (C.-Y.H.); (J.-X.C.); (Y.-C.S.)
| | - Ying-Nan Chan
- Material and Chemical Research Laboratories, Industrial Technology Research Institute, Hsinchu 31040, Taiwan; (Y.-N.C.); (K.-C.C.); (T.-M.L.)
| | - Kuo-Chan Chiou
- Material and Chemical Research Laboratories, Industrial Technology Research Institute, Hsinchu 31040, Taiwan; (Y.-N.C.); (K.-C.C.); (T.-M.L.)
| | - Tzong-Ming Lee
- Material and Chemical Research Laboratories, Industrial Technology Research Institute, Hsinchu 31040, Taiwan; (Y.-N.C.); (K.-C.C.); (T.-M.L.)
| | - Chih-Chia Cheng
- Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei 10607, Taiwan;
| | - Chih-Wei Chiu
- Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan; (W.A.L.S.); (C.-Y.H.); (J.-X.C.); (Y.-C.S.)
| |
Collapse
|
21
|
Linganna K, In JH, Kim SH, Han K, Choi JH. Engineering of TeO 2-ZnO-BaO-Based Glasses for Mid-Infrared Transmitting Optics. Materials (Basel) 2020; 13:E5829. [PMID: 33371348 PMCID: PMC7767337 DOI: 10.3390/ma13245829] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 12/04/2020] [Accepted: 12/15/2020] [Indexed: 11/23/2022]
Abstract
In this paper, the glass systems, TeO2-ZnO-BaO (TZB), TeO2-ZnO-BaO-Nb2O5 (TZB-Nb) and TeO2-ZnO-BaO-MoO3 (TZB-Mo), were fabricated by the traditional melt-quench protocol for use as mid-infrared (mid-IR) transmitting optical material. The effect of Nb2O5 and MoO3 on the key glass material properties was studied through various techniques. From the Raman analysis, it was found that the structural modification was clear with the addition of both Nb2O5 and MoO3 in the TZB system. The transmittance of studied glasses was measured and found that the optical window covered a region from 0.4 to 6 μm. The larger linear refractive index was obtained for the Nb2O5-doped TZB glass system than that of other studied systems. High glass transition temperature, low thermo-mechanical coefficient and high Knoop hardness were noticed in the Nb2O5-doped TZB glass system due to the increase in cross-linking density and rigidity in the tellurite network. The results suggest that the Nb2O5-doped TZB optical glasses could be a promising material for mid-infrared transmitting optics.
Collapse
Affiliation(s)
- Kadathala Linganna
- Intelligent Optical Module Research Center, Korea Photonics Technology Institute, Gwangju 61007, Korea; (J.-H.I.); (S.H.K.); (K.H.)
| | | | | | | | - Ju Hyeon Choi
- Intelligent Optical Module Research Center, Korea Photonics Technology Institute, Gwangju 61007, Korea; (J.-H.I.); (S.H.K.); (K.H.)
| |
Collapse
|
22
|
Arbogast A, Roy S, Nycz A, Noakes MW, Masuo C, Babu SS. Investigating the Linear Thermal Expansion of Additively Manufactured Multi-Material Joining between Invar and Steel. Materials (Basel) 2020; 13:E5683. [PMID: 33322830 DOI: 10.3390/ma13245683] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 11/25/2020] [Accepted: 12/09/2020] [Indexed: 11/16/2022]
Abstract
This work investigated the linear thermal expansion properties of a multi-material specimen fabricated with Invar M93 and A36 steel. A sequence of tests was performed to investigate the viability of additively manufactured Invar M93 for lowering the coefficient of thermal expansion (CTE) in multi-material part tooling. Invar beads were additively manufactured on a steel base plate using a fiber laser system, and samples were taken from the steel, Invar, and the interface between the two materials. The CTE of the samples was measured between 40 °C and 150 °C using a thermomechanical analyzer, and the elemental composition was studied with energy dispersive X-ray spectroscopy. The CTE of samples taken from the steel and the interface remained comparable to that of A36 steel; however, deviations between the thermal expansion values were prevalent due to element diffusion in and around the heat-affected zone. The CTEs measured from the Invar bead were lower than those from the other sections with the largest and smallest thermal expansion values being 10.40 μm/m-K and 2.09 μm/m-K. In each of the sections, the largest CTE was measured from samples taken from the end of the weld beads. An additional test was performed to measure the aggregate expansion of multi-material tools. Invar beads were welded on an A36 steel plate. The invar was machined, and the sample was heated in an oven from 40 °C and 160 °C. Strain gauges were placed on the surface of the part and were used to analyze how the combined thermal expansions of the invar and steel would affect the thermal expansion on the surface of a tool. There were small deviations between the expansion values measured by gauges placed in different orientations, and the elongation of the sample was greatest along the dimension containing a larger percentage of steel. On average, the expansion of the machined Invar surface was 42% less than the expansion of the steel surface. The results of this work demonstrate that additively manufactured Invar can be utilized to decrease the CTE for multi-material part tooling.
Collapse
|
23
|
Ye X, Tian B, Guo Y, Fan F, Cai A. A novel dry-blending method to reduce the coefficient of thermal expansion of polymer templates for OTFT electrodes. Beilstein J Nanotechnol 2020; 11:671-677. [PMID: 32395396 PMCID: PMC7188987 DOI: 10.3762/bjnano.11.53] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 03/28/2020] [Indexed: 06/11/2023]
Abstract
Among the patterning technologies for organic thin-film transistors (OTFTs), the fabrication of OTFT electrodes using polymer templates has attracted much attention. However, deviations in the electrode alignment occur because the coefficient of thermal expansion (CTE) of the polymer template is much higher than the CTE of the dielectric layer. Here, a novel dry-blending method is described in which SiO2 nanoparticles are filled into a grooved silicon template, followed by permeation of polydimethylsiloxane (PDMS) into the SiO2 nanoparticle gaps. The SiO2 nanoparticles in the groove are extracted by curing and peeling off PDMS to prepare a PDMS/SiO2 composite template with a nanoparticle content of 83.8 wt %. The composite template has a CTE of 96 ppm/°C, which is a reduction by 69.23% compared with the original PDMS template. Finally, we achieved the alignment of OTFT electrodes using the composite template.
Collapse
Affiliation(s)
- Xiangdong Ye
- School of Mechanical and Electrical Engineering, Xi’an University of Architecture and Technology, Xi’an 710055, China
- Shaanxi Key Laboratory of Nano Materials and Technology, Xi’an 710055, China
| | - Bo Tian
- School of Mechanical and Electrical Engineering, Xi’an University of Architecture and Technology, Xi’an 710055, China
- Shaanxi Key Laboratory of Nano Materials and Technology, Xi’an 710055, China
| | - Yuxuan Guo
- School of Mechanical and Electrical Engineering, Xi’an University of Architecture and Technology, Xi’an 710055, China
- Shaanxi Key Laboratory of Nano Materials and Technology, Xi’an 710055, China
| | - Fan Fan
- School of Automation, Xi'an University of Posts and Telecommunications, Xi’an 710121, China
| | - Anjiang Cai
- School of Mechanical and Electrical Engineering, Xi’an University of Architecture and Technology, Xi’an 710055, China
- Shaanxi Key Laboratory of Nano Materials and Technology, Xi’an 710055, China
| |
Collapse
|
24
|
Hassan T, Jamshaid H, Mishra R, Khan MQ, Petru M, Novak J, Choteborsky R, Hromasova M. Acoustic, Mechanical and Thermal Properties of Green Composites Reinforced with Natural Fibers Waste. Polymers (Basel) 2020; 12:polym12030654. [PMID: 32183033 PMCID: PMC7183085 DOI: 10.3390/polym12030654] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 03/06/2020] [Accepted: 03/11/2020] [Indexed: 11/16/2022] Open
Abstract
The use of acoustic panels is one of the most important methods for sound insulation in buildings. Moreover, it has become increasingly important to use green/natural origin materials in this area to reduce environmental impact. This study focuses on the investigation of acoustic, mechanical and thermal properties of natural fiber waste reinforced green epoxy composites. Three different types of fiber wastes were used, e.g., cotton, coconut and sugarcane with epoxy as the resin. Different fiber volume fractions, i.e., 10%, 15% and 20% for each fiber were used with a composite thickness of 3 mm. The sound absorption coefficient, impact strength, flexural strength, thermal conductivity, diffusivity, coefficient of thermal expansion and thermogravimetric properties of all samples were investigated. It has been found that by increasing the fiber content, the sound absorption coefficient also increases. The coconut fiber-based composites show a higher sound absorption coefficient than in the other fiber-reinforced composites. The impact and flexural strength of the cotton fiber-reinforced composite samples are higher than in other samples. The coefficient of thermal expansion of the cotton fiber-based composite is also higher than the other composites. Thermogravimetric analysis revealed that all the natural fiber-reinforced composites can sustain till 300 °C with a minor weight loss. The natural fiber-based composites can be used in building interiors, automotive body parts and household furniture. Such composite development is an ecofriendly approach to the acoustic world.
Collapse
Affiliation(s)
- Tufail Hassan
- Faculty of Textile Engineering, National Textile University, Faisalabad 37610, Pakistan; (T.H.); (M.Q.K.)
| | - Hafsa Jamshaid
- Faculty of Textile Engineering, National Textile University, Faisalabad 37610, Pakistan; (T.H.); (M.Q.K.)
- Protective Textile Group, National Textile University, Faisalabad 37610, Pakistan
- Correspondence: (H.J.); (R.M.)
| | - Rajesh Mishra
- Faculty of Engineering, Czech University of Life Sciences Prague, Kamýcká 129, 165 00 Praha-Suchdol, Czech Republic; (R.C.); (M.H.)
- Correspondence: (H.J.); (R.M.)
| | - Muhammad Qamar Khan
- Faculty of Textile Engineering, National Textile University, Faisalabad 37610, Pakistan; (T.H.); (M.Q.K.)
| | - Michal Petru
- Department of Machinery Construction, Institute for Nanomaterials, Advanced Technology and Innovation, Technical University of Liberec, Studentska 2, 46117 Liberec, Czech Republic;
- Faculty of Mechanical Engineering, Technical University of Liberec, Studentska 2, 46117 Liberec, Czech Republic;
| | - Jan Novak
- Faculty of Mechanical Engineering, Technical University of Liberec, Studentska 2, 46117 Liberec, Czech Republic;
| | - Rostislav Choteborsky
- Faculty of Engineering, Czech University of Life Sciences Prague, Kamýcká 129, 165 00 Praha-Suchdol, Czech Republic; (R.C.); (M.H.)
| | - Monika Hromasova
- Faculty of Engineering, Czech University of Life Sciences Prague, Kamýcká 129, 165 00 Praha-Suchdol, Czech Republic; (R.C.); (M.H.)
| |
Collapse
|
25
|
Moon KH, Chae B, Kim KS, Lee SW, Jung YM. Preparation and Characterization of Transparent Polyimide⁻Silica Composite Films Using Polyimide with Carboxylic Acid Groups. Polymers (Basel) 2019; 11:polym11030489. [PMID: 30960474 PMCID: PMC6473655 DOI: 10.3390/polym11030489] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/22/2019] [Accepted: 03/07/2019] [Indexed: 11/16/2022] Open
Abstract
Polyimide (PI) composite films with thicknesses of approximately 100 µm were prepared via a sol–gel reaction of 3-aminopropyltrimethoxysilane (APTMS) with poly(amic acid) (PAA) composite solutions using a thermal imidization process. PAA was synthesized by a conventional condensation reaction of two diamines, 3,5-diaminobenzoic acid (DABA), which has a carboxylic acid side group, and 2,2′-bis(trifluoromethyl)benzidine (TFMB), with 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) in N,N-dimethylacetamide (DMAc). The PAA–silica composite solutions were prepared by mixing PAA with carboxylic acid side groups and various amounts of APTMS in a sol–gel process in DMAc using hydrochloric acid as a catalyst. The obtained PI–silica composite films showed relatively good thermal stability, and the thermal stability increased with increasing APTMS content. The optical properties and in-plane coefficient of thermal expansion (CTE) values of the PI–silica composite films were investigated. The CTE of the PI–silica composite films changed from 52.0 to 42.1 ppm/°C as the initial content of APTMS varied. The haze values and yellowness indices of the composite films increased as a function of the APTMS content.
Collapse
Affiliation(s)
- Kwan Ho Moon
- School of Chemical Engineering, Yeungnam University, Gyeongsan 38541, Korea.
| | - Boknam Chae
- Pohang Accelerator Laboratory, POSTECH, Pohang 37673, Korea.
| | - Ki Seung Kim
- School of Chemical Engineering, Yeungnam University, Gyeongsan 38541, Korea.
| | - Seung Woo Lee
- School of Chemical Engineering, Yeungnam University, Gyeongsan 38541, Korea.
| | - Young Mee Jung
- Department of Chemistry, Kangwon National University, Chunchon 24341, Korea.
| |
Collapse
|
26
|
Urgessa G, Choi KB, Yeon JH. Internal Relative Humidity, Autogenous Shrinkage, and Strength of Cement Mortar Modified with Superabsorbent Polymers. Polymers (Basel) 2018; 10:E1074. [PMID: 30960999 PMCID: PMC6403663 DOI: 10.3390/polym10101074] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 09/26/2018] [Accepted: 09/26/2018] [Indexed: 11/19/2022] Open
Abstract
Laboratory evaluations were performed to investigate the effect of internal curing (IC) by superabsorbent polymers (SAP) on the internal relative humidity (IRH), autogenous shrinkage, coefficient of thermal expansion (CTE), and strength characteristics of low water-cement ratio (w/c) mortars. Four types of SAP with different cross-linking densities and particle sizes were used. Test results showed that the SAP inclusion effectively mitigated the IRH drops due to self-desiccation and corresponding autogenous shrinkage, and the IC effectiveness tended to increase with an increased SAP dosage. The greater the cross-linking density and particle size of SAP, the less the IRH drop and autogenous shrinkage. The trend of autogenous shrinkage developments was in good agreement with that of IRH changes, with nearly linear relationships between them. Both immediate deformation (ID)-based and full response-based CTEs were rarely affected by SAP inclusions. There were no substantial losses in compressive and flexural strengths of SAP-modified mortar compared to reference plain mortar. The findings revealed that SAPs can be effectively used to reduce the shrinkage cracking potential of low w/c cement-based materials at early ages, without compromising mechanical and thermal characteristics.
Collapse
Affiliation(s)
- Girum Urgessa
- Sid and Reva Dewberry Department of Civil, Environmental, and Infrastructure Engineering, George Mason University, Fairfax, VA 22030, USA.
| | - Ki-Bong Choi
- Department of Architectural Engineering, Gachon University, Seongnam 13120, Korea.
| | - Jung Heum Yeon
- Department of Civil and Environmental Engineering, Gachon University, Seongnam 13120, Korea.
| |
Collapse
|
27
|
Xie Q, Fu K, Liang S, Liu B, Lu L, Yang X, Huang Z, Lü F. Micro-Structure and Thermomechanical Properties of Crosslinked Epoxy Composite Modified by Nano-SiO₂: A Molecular Dynamics Simulation. Polymers (Basel) 2018; 10:E801. [PMID: 30960726 PMCID: PMC6403537 DOI: 10.3390/polym10070801] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 07/19/2018] [Accepted: 07/19/2018] [Indexed: 01/15/2023] Open
Abstract
Establishing the relationship among the composition, structure and property of the associated materials at the molecular level is of great significance to the rational design of high-performance electrical insulating Epoxy Resin (EP) and its composites. In this paper, the molecular models of pure Diglycidyl Ether of Bisphenol A resin/Methyltetrahydrophthalic Anhydride (DGEBA/MTHPA) and their nanocomposites containing nano-SiO₂ with different particle sizes were constructed. The effects of nano-SiO₂ dopants and the crosslinked structure on the micro-structure and thermomechanical properties were investigated using molecular dynamics simulations. The results show that the increase of crosslinking density enhances the thermal and mechanical properties of pure EP and EP nanocomposites. In addition, doping nano-SiO₂ particles into EP can effectively improve the properties, as well, and the effectiveness is closely related to the particle size of nano-SiO₂. Moreover, the results indicate that the glass transition temperature (Tg) value increases with the decreasing particle size. Compared with pure EP, the Tg value of the 6.5 Å composite model increases by 6.68%. On the contrary, the variation of the Coefficient of Thermal Expansion (CTE) in the glassy state demonstrates the opposite trend compared with Tg. The CTE of the 10 Å composite model is the lowest, which is 7.70% less than that of pure EP. The mechanical properties first increase and then decrease with the decreasing particle size. Both the Young's modulus and shear modulus reach the maximum value at 7.6 Å, with noticeable increases by 12.60% and 8.72%, respectively compared to the pure EP. In addition, the thermal and mechanical properties are closely related to the Fraction of Free Volume (FFV) and Mean Squared Displacement (MSD). The crosslinking process and the nano-SiO₂ doping reduce the FFV and MSD value in the model, resulting in better thermal and mechanical properties.
Collapse
Affiliation(s)
- Qing Xie
- State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Baoding 071000, China.
| | - Kexin Fu
- State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Baoding 071000, China.
| | - Shaodong Liang
- State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Baoding 071000, China.
| | - Bowen Liu
- State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Baoding 071000, China.
| | - Lu Lu
- State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Baoding 071000, China.
| | - Xueming Yang
- Department of Power Engineering, North China Electric Power University, Baoding 071003, China.
| | - Zhengyong Huang
- State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing University, Chongqing 400044, China.
| | - Fangcheng Lü
- State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Baoding 071000, China.
| |
Collapse
|
28
|
Li F, Liu J, Liu X, Wang Y, Gao X, Meng X, Tu G. High Performance Soluble Polyimides from Ladder-Type Fluorinated Dianhydride with Polymorphism. Polymers (Basel) 2018; 10:E546. [PMID: 30966580 PMCID: PMC6415444 DOI: 10.3390/polym10050546] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 05/15/2018] [Accepted: 05/16/2018] [Indexed: 02/03/2023] Open
Abstract
A novel rigid semi-alicyclic dianhydride 9,10-difluoro-9,10-bis(trifluoromethyl)-9,10-dihydroanthracene-2,3,6,7-tetracarboxylic acid dianhydride (8FDA) was reported, and its single crystal X-ray diffraction result revealed the existence of the polymorphic structure in this compound. The detail geometric configuration transition during the synthesized process was investigated, exhibiting a transition of from trans- to cis- when the hydroxyl groups were substituted by fluoride with diethylaminosulfur trifluoride (DAST). Compared with the dianhydride 4,4'-(Hexaflouroisopropylidene) diphthalic anhydride (6FDA) and 1S,2R,4S,5R-cyclohexanetetracarboxylic dianhydride (HPMDA), the resulting polyimide (PI) films based on 8FDA exhibited an obviously higher glass transition temperature (Tg, 401 °C) and a much lower coefficient of thermal expansion (CTE, 14 ppm K-1). This indicates that 8FDA is an ideal building block in high-performance soluble PIs with low CTE.
Collapse
Affiliation(s)
- Fu Li
- Wuhan National Research Center for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China.
| | - Jikang Liu
- Wuhan National Research Center for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China.
| | - Xiangfu Liu
- Wuhan National Research Center for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China.
| | - Yao Wang
- Wuhan National Research Center for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China.
| | - Xiang Gao
- School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan 403052, China.
| | - Xianggao Meng
- Key Laboratory of Pesticide and Chemical Biology of the Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, China.
| | - Guoli Tu
- Wuhan National Research Center for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China.
| |
Collapse
|
29
|
Geng G, Ma X, Geng H, Wu Y. Effect of Load on the Thermal Expansion Behavior of T700 Carbon Fiber Bundles. Polymers (Basel) 2018; 10:E152. [PMID: 30966188 PMCID: PMC6415041 DOI: 10.3390/polym10020152] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 01/26/2018] [Accepted: 01/30/2018] [Indexed: 11/16/2022] Open
Abstract
T700 carbon fiber bundles (CFBs) are the primary material used for manufacturing cable-net in a deployable antenna. In this paper, the relationships between the coefficient of thermal expansion (CTE) of T700 CFBs and the experimental load were investigated. The microstructure of T700 CFBs was analyzed with Raman spectra and XRD before and after the thermomechanical test. The measured results indicated that the T700 CFBs that were parallel to the axis had negative expansion characteristics when in a temperature range of -150⁻+150 °C. The thermal strain that occurred during the heating and the cooling thermal cycles had an unclosed curve that served as the loop. When the thermal cycles were the same, the position of the strain loop and the length of the sample exhibited regular change. The average of the CTEs decreased as the experimental load increased. The microstructural analysis suggested that the degree of structural order and the degree of orientation along the fiber axis improved with the experimental load increase. The change of microstructure parameters could be the primary cause of the negative CTE's variation within the T700 CFBs. The experimental results provide some guidelines for improving the cable-net material selection.
Collapse
Affiliation(s)
- Guoliang Geng
- School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
| | - Xiaofei Ma
- CAST-Xi'an Institute of Space Radio Technology, Xi'an 710100, China.
| | - Hongbin Geng
- School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
| | - Yiyong Wu
- School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
| |
Collapse
|
30
|
Papadimitriou I, Utton C, Tsakiropoulos P. The impact of Ti and temperature on the stability of Nb 5Si 3 phases: a first-principles study. Sci Technol Adv Mater 2017; 18:467-479. [PMID: 28740563 PMCID: PMC5508373 DOI: 10.1080/14686996.2017.1341802] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 06/08/2017] [Accepted: 06/09/2017] [Indexed: 06/02/2023]
Abstract
Nb-silicide based alloys could be used at T > 1423 K in future aero-engines. Titanium is an important additive to these new alloys where it improves oxidation, fracture toughness and reduces density. The microstructures of the new alloys consist of an Nb solid solution, and silicides and other intermetallics can be present. Three Nb5Si3 polymorphs are known, namely αNb5Si3 (tI32 Cr5B3-type, D8l), βNb5Si3 (tI32 W5Si3-type, D8m) and γNb5Si3 (hP16 Mn5Si3-type, D88). In these 5-3 silicides Nb atoms can be substituted by Ti atoms. The type of stable Nb5Si3 depends on temperature and concentration of Ti addition and is important for the stability and properties of the alloys. The effect of increasing concentration of Ti on the transition temperature between the polymorphs has not been studied. In this work first-principles calculations were used to predict the stability and physical properties of the various Nb5Si3 silicides alloyed with Ti. Temperature-dependent enthalpies of formation were computed, and the transition temperature between the low (α) and high (β) temperature polymorphs of Nb5Si3 was found to decrease significantly with increasing Ti content. The γNb5Si3 was found to be stable only at high Ti concentrations, above approximately 50 at. % Ti. Calculation of physical properties and the Cauchy pressures, Pugh's index of ductility and Poisson ratio showed that as the Ti content increased, the bulk moduli of all silicides decreased, while the shear and elastic moduli and the Debye temperature increased for the αNb5Si3 and γNb5Si3 and decreased for βNb5Si3. With the addition of Ti the αNb5Si3 and γNb5Si3 became less ductile, whereas the βNb5Si3 became more ductile. When Ti was added in the αNb5Si3 and βNb5Si3 the linear thermal expansion coefficients of the silicides decreased, but the anisotropy of coefficient of thermal expansion did not change significantly.
Collapse
Affiliation(s)
- Ioannis Papadimitriou
- Department of Materials Science and Engineering, The University of Sheffield, Sheffield, UK
| | - Claire Utton
- Department of Materials Science and Engineering, The University of Sheffield, Sheffield, UK
| | - Panos Tsakiropoulos
- Department of Materials Science and Engineering, The University of Sheffield, Sheffield, UK
| |
Collapse
|
31
|
Molina JM, Rodríguez-Guerrero A, Louis E, Rodríguez-Reinoso F, Narciso J. Porosity Effect on Thermal Properties of Al-12 wt % Si/Graphite Composites. Materials (Basel) 2017; 10:ma10020177. [PMID: 28772536 PMCID: PMC5459103 DOI: 10.3390/ma10020177] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 01/24/2017] [Accepted: 02/08/2017] [Indexed: 11/16/2022]
Abstract
The effect of porosity on the thermal conductivity and the coefficient of thermal expansion of composites obtained by infiltration of Al-12 wt % Si alloy into graphite particulate preforms has been determined. Highly irregular graphite particles were used to fabricate the preforms. The thermal conductivity of these composites gradually increases with the applied infiltration pressure given the inherent reduction in porosity. A simple application of the Hasselman-Johnson model in a two-step procedure (that accounts for the presence of both graphite particles and voids randomly dispersed in a metallic matrix) offers a good estimation of the experimental results. As concerns the coefficient of thermal expansion, the results show a slight increase with saturation being approximately in the range 14.6–15.2 × 10−6 K−1 for a saturation varying from 86% up to 100%. Results lie within the standard Hashin-Strikman bounds.
Collapse
Affiliation(s)
- José-Miguel Molina
- Instituto Universitario de Materiales, Universidad de Alicante, Apdo 99, Alicante E-03080, Spain.
- Departamento de Química Inorgánica, Universidad de Alicante, Apdo 99, Alicante E-03080, Spain.
| | | | - Enrique Louis
- Instituto Universitario de Materiales, Universidad de Alicante, Apdo 99, Alicante E-03080, Spain.
- Departamento de Física Aplicada, Universidad de Alicante, Apdo 99, Alicante E-03080, Spain.
- Unidad Asociada del Consejo Superior de Investigaciones Científicas, Universidad de Alicante, Apdo 99, Alicante E-03080, Spain.
| | - Francisco Rodríguez-Reinoso
- Instituto Universitario de Materiales, Universidad de Alicante, Apdo 99, Alicante E-03080, Spain.
- Departamento de Química Inorgánica, Universidad de Alicante, Apdo 99, Alicante E-03080, Spain.
| | - Javier Narciso
- Instituto Universitario de Materiales, Universidad de Alicante, Apdo 99, Alicante E-03080, Spain.
- Departamento de Química Inorgánica, Universidad de Alicante, Apdo 99, Alicante E-03080, Spain.
| |
Collapse
|
32
|
Rodriguez O, Matinmanesh A, Phull S, Schemitsch EH, Zalzal P, Clarkin OM, Papini M, Towler MR. Silica-Based and Borate-Based, Titania-Containing Bioactive Coatings Characterization: Critical Strain Energy Release Rate, Residual Stresses, Hardness, and Thermal Expansion. J Funct Biomater 2016; 7:E32. [PMID: 27916951 DOI: 10.3390/jfb7040032] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 11/25/2016] [Accepted: 11/28/2016] [Indexed: 11/16/2022] Open
Abstract
Silica-based and borate-based glass series, with increasing amounts of TiO2 incorporated, are characterized in terms of their mechanical properties relevant to their use as metallic coating materials. It is observed that borate-based glasses exhibit CTE (Coefficient of Thermal Expansion) closer to the substrate’s (Ti6Al4V) CTE, translating into higher mode I critical strain energy release rates of glasses and compressive residual stresses and strains at the coating/substrate interface, outperforming the silica-based glasses counterparts. An increase in the content of TiO2 in the glasses results in an increase in the mode I critical strain energy release rate for both the bulk glass and for the coating/substrate system, proving that the addition of TiO2 to the glass structure enhances its toughness, while decreasing its bulk hardness. Borate-based glass BRT3, with 15 mol % TiO2 incorporated, exhibits superior properties overall compared to the other proposed glasses in this work, as well as 45S5 Bioglass® and Pyrex.
Collapse
|
33
|
Qiang Z, Ning L, Yanan Z, Jiazhen Y, Wenbo L. [Effect of Al₂O₃ sandblasting on the bond strength between 3mol% yttrium-stabilized tetragonal zirconium polycrystal zirconia framework and veneering porcelain]. Hua Xi Kou Qiang Yi Xue Za Zhi 2015; 33:638-641. [PMID: 27051960 PMCID: PMC7030379 DOI: 10.7518/hxkq.2015.06.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 09/10/2015] [Indexed: 06/05/2023]
Abstract
OBJECTIVE The effect of sandblasting on the bond strength between 3mol% yttrium-stabilized tetragonal zirconium polycrystal (3Y-TZP) zirconia framework and veneering porcelain was evaluated. METHODS A total of 21 specimens [(25 ± 1) mm x (3 ± 0.1) mmx (0.5 ± 0.05) mm] were prepared according to ISO 9693. The specimens were then randomly divided into 3 groups. Sandblasting was performed on 2 meshes of Al₂O₃ particles: group A with mesh 110 and group B with mesh 80. Group C, which was not sandblasted, was the control group. The surface roughness of the zirconia framework, as well as the bond strength between 3Y-TZP zirconia framework and veneering porcelain, was measured. The interface microstructure was observed by scanning electron microscope (SEM), and elemental distribution was detected by energy dispersive spectroscopy (EDS). RESULTS Surface roughness values were (1.272 ± 0.149) μm for group A, (0.622 ± 0.113) μm for group B, and (0.221 ± 0.065) μm for group C. Statistical significance were found among groups (P < 0.05). The bond strength values were (28.21 ± 1.52) MPa for group A, (27.71 ± 1.27) MPa for group B, and (24.87 ± 3.84) MPa for group C. Statistical significance was found between group A and group C (P < 0.05), whereas the other groups had no statistical significance (P > 0.05). Interface adhesion failure was the primary performance. SEM images showed the close interface bonding, and EDS showed that the interface had no obvious element penetration. CONCLUSION Al₂O₃ sandblasting can slightly enhance the bond strength between zirconia framework and veneering porcelain.
Collapse
|
34
|
Abstract
This paper contains descriptions of the construction and use over the temperature range -27 °C to 570 °C of a Merritt-Saunders (optical interferometric) linear thermal expansion apparatus. Measurements of thermal expansion are reported for platinum and for two platinum-rhodium alloys (nominally 12 wt% Rh and 20 wt% Rh). Detailed analyses are given of the measurement uncertainties involved in the experiment and of the representation of the data by polynomials in the sample temperatures. The data show precision at the 1-ppm level and good agreement with results already published.
Collapse
Affiliation(s)
- R E Edsinger
- National Bureau of Standards, Gaithersburg, MD 20899
| | - M L Reilly
- National Bureau of Standards, Gaithersburg, MD 20899
| | - J F Schooley
- National Bureau of Standards, Gaithersburg, MD 20899
| |
Collapse
|