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Behjat A, Sanaei S, Mosallanejad MH, Atapour M, Sheikholeslam M, Saboori A, Iuliano L. A novel titanium alloy for load-bearing biomedical implants: Evaluating the antibacterial and biocompatibility of Ti536 produced via electron beam powder bed fusion additive manufacturing process. BIOMATERIALS ADVANCES 2024; 163:213928. [PMID: 38941776 DOI: 10.1016/j.bioadv.2024.213928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 05/28/2024] [Accepted: 06/17/2024] [Indexed: 06/30/2024]
Abstract
Additive manufacturing (AM) of Ti-based biomedical implants is a pivotal research topic because of its ability to produce implants with complicated geometries. Despite desirable mechanical properties and biocompatibility of Ti alloys, one major drawback is their lack of inherent antibacterial properties, increasing the risk of postoperative infections. Hence, this research focuses on the Ti536 (Ti5Al3V6Cu) alloy, developed through Electron Beam Powder Bed Fusion (EB-PBF), exploring bio-corrosion, antibacterial features, and cell biocompatibility. The microstructural characterization revealed grain refinement and the formation of Ti2Cu precipitates with different morphologies and sizes in the Ti matrix. Electrochemical tests showed that Cu content minimally influenced the corrosion current density, while it slightly affected the stability, defect density, and chemical composition of the passive film. According to the findings, the Ti536 alloy demonstrated enhanced antibacterial properties without compromising its cell biocompatibility and corrosion behavior, thanks to Ti2Cu precipitates. This can be attributed to both the release of Cu ions and the Ti2Cu precipitates. The current study suggests that the EB-PBF fabricated Ti536 sample is well-suited for use in load-bearing applications within the medical industry. This research also offers an alloy design roadmap for novel biomedical Ti-based alloys with superior biological performance using AM methods.
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Affiliation(s)
- Amir Behjat
- Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran; Integrated Additive Manufacturing Center, Department of Management and Production Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy
| | - Saber Sanaei
- Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran
| | - Mohammad Hossein Mosallanejad
- Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran; Integrated Additive Manufacturing Center, Department of Management and Production Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy
| | - Masoud Atapour
- Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran.
| | - Mohammadali Sheikholeslam
- Department of Biomaterials, Tissue Engineering and Nanotechnology, School of Advanced Technologies in Medicine, Isfahan University of Medical Sciences, Isfahan 81746-73461, Iran
| | - Abdollah Saboori
- Integrated Additive Manufacturing Center, Department of Management and Production Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy.
| | - Luca Iuliano
- Integrated Additive Manufacturing Center, Department of Management and Production Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy
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2
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Nomura Y, Okada M, Manaka T, Tsuchiya T, Iwasaki M, Matsuda K, Ishimoto T. Effect of Partial Substitution of Zr for Ti Solvent on Young's Modulus, Strength, and Biocompatibility in Beta Ti Alloy. MATERIALS (BASEL, SWITZERLAND) 2024; 17:2548. [PMID: 38893812 PMCID: PMC11173081 DOI: 10.3390/ma17112548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Revised: 05/20/2024] [Accepted: 05/22/2024] [Indexed: 06/21/2024]
Abstract
In orthopedics and dentistry, there is an urgent need to obtain low-stiffness implants that suppress the stress shielding caused by the use of metallic implants. In this study, we aimed to fabricate alloys that can reduce the stiffness by increasing the strength while maintaining a low Young's modulus based on the metastable β-Ti alloy. We designed alloys in which Ti was partially replaced by Zr based on the ISO-approved metastable β-Ti alloy Ti-15Mo-5Zr-3Al. All alloys prepared by arc melting and subsequent solution treatment showed a single β-phase solid solution, with no formation of the ω-phase. The alloys exhibited a low Young's modulus equivalent to that of Ti-15Mo-5Zr-3Al and a high strength superior to that of Ti-15Mo-5Zr-3Al and Ti-6Al-4V. This strengthening was presumed to be due to solid-solution strengthening. The biocompatibility of the alloys was as good as or better than that of Ti-6Al-4V. These alloys have potential as metallic materials suitable for biomedical applications.
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Affiliation(s)
- Yusuke Nomura
- Department of Materials Design and Engineering, Faculty of Sustainable Design, University of Toyama, Toyama 930-8555, Japan; (Y.N.); (M.O.); (T.T.); (K.M.)
| | - Mio Okada
- Department of Materials Design and Engineering, Faculty of Sustainable Design, University of Toyama, Toyama 930-8555, Japan; (Y.N.); (M.O.); (T.T.); (K.M.)
| | - Tomoyo Manaka
- Aluminium Research Center, University of Toyama, Toyama 930-8555, Japan;
| | - Taiki Tsuchiya
- Department of Materials Design and Engineering, Faculty of Sustainable Design, University of Toyama, Toyama 930-8555, Japan; (Y.N.); (M.O.); (T.T.); (K.M.)
| | - Mami Iwasaki
- Department of Mechanical Engineering, University of Toyama, Toyama 930-8555, Japan;
| | - Kenji Matsuda
- Department of Materials Design and Engineering, Faculty of Sustainable Design, University of Toyama, Toyama 930-8555, Japan; (Y.N.); (M.O.); (T.T.); (K.M.)
| | - Takuya Ishimoto
- Aluminium Research Center, University of Toyama, Toyama 930-8555, Japan;
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Takahashi M, Sato K, Togawa G, Takada Y. Mechanical Properties of Ti-Nb-Cu Alloys for Dental Machining Applications. J Funct Biomater 2022; 13:jfb13040263. [PMID: 36547524 PMCID: PMC9785869 DOI: 10.3390/jfb13040263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/07/2022] [Accepted: 11/21/2022] [Indexed: 11/24/2022] Open
Abstract
Titanium has excellent biocompatibility and good corrosion resistance and is extensively used in dental implants and denture bases. However, pure titanium lacks the strength for use in dental prostheses that require relatively high strength. We developed 15 different types of Ti-Nb-Cu alloys and investigated their alloy phases and mechanical properties, including tensile and yield strength, elongation after fracture, and Vickers hardness. The alloy phases of Ti-8%Nb-2%Cu and Ti-13%Nb-2%Cu were α + β, while those of Ti-5%Nb-5%Cu and Ti-10%Nb-5%Cu were α + Ti2Cu. The tensile strength and hardness of these alloys were significantly higher than those of titanium; however, their elongation was less. In particular, the yield strength of these alloys was more than twice that of titanium. These differences in mechanical properties are attributable to solid-solution strengthening and precipitation strengthening. Other compositions with an alloy phase of α + β + Ti2Cu or β + Ti2Cu had high hardness but not high strength. These results suggest that the Ti-8%Nb-2%Cu, Ti-5%Nb-5%Cu, Ti-13%Nb-2%Cu, and Ti-10%Nb-5%Cu alloys can be applied to dental prostheses, which are subject to very high forces from accessories such as long-span bridges, clasps, implant-retained superstructures, and narrow-diameter implants.
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Vilardell AM, Krakhmalev P, Yadroitsava I, Yadroitsev I, Garcia-Giralt N. In Vitro Characterization of In Situ Alloyed Ti6Al4V(ELI)-3 at.% Cu Obtained by Laser Powder Bed Fusion. MATERIALS 2021; 14:ma14237260. [PMID: 34885415 PMCID: PMC8658412 DOI: 10.3390/ma14237260] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 11/22/2021] [Accepted: 11/25/2021] [Indexed: 11/16/2022]
Abstract
The intensive cytotoxicity of pure copper is effectively kills bacteria, but it can compromise cellular behavior, so a rational balance must be found for Cu-loaded implants. In the present study, the individual and combined effect of surface composition and roughness on osteoblast cell behavior of in situ alloyed Ti6Al4V(ELI)-3 at.% Cu obtained by laser powder bed fusion was studied. Surface composition was studied using scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction. Surface roughness measurements were carried out using confocal microscopy. In vitro osteoblast performance was evaluated by means of cell morphology observation of cell viability, proliferation, and mineralization. In vitro studies were performed at 1, 7, and 14 days of cell culture, except for cell mineralization at 28 days, on grounded and as-built (rough) samples with and without 3 at.% Cu. The addition of 3 at.% Cu did not show cell cytotoxicity but inhibited cell proliferation. Cell mineralization tends to be higher for samples with 3 at.% Cu content. Surface roughness inhibited cell proliferation too, but showed enhanced cell mineralization capacity and therefore, higher osteoblast performance, especially when as-built samples contained 3 at.% Cu. Cell proliferation was only observed on ground samples without Cu but showed the lowest cell mineralization.
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Affiliation(s)
- Anna Martín Vilardell
- Department of Engineering and Physics, Karlstad University, 651 88 Karlstad, Sweden;
- Correspondence:
| | - Pavel Krakhmalev
- Department of Engineering and Physics, Karlstad University, 651 88 Karlstad, Sweden;
| | - Ina Yadroitsava
- Department of Mechanical Engineering and Mechatronics, Central University of Technology, Bloemfontein 9300, Free State, South Africa; (I.Y.); (I.Y.)
| | - Igor Yadroitsev
- Department of Mechanical Engineering and Mechatronics, Central University of Technology, Bloemfontein 9300, Free State, South Africa; (I.Y.); (I.Y.)
| | - Natalia Garcia-Giralt
- IMIM (Institut Hospital del Mar d’Investigacions Mèdiques), CIBERFES, ISCIII, Doctor Aiguader 88, 08003 Barcelona, Spain;
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Zhang E, Zhao X, Hu J, Wang R, Fu S, Qin G. Antibacterial metals and alloys for potential biomedical implants. Bioact Mater 2021; 6:2569-2612. [PMID: 33615045 PMCID: PMC7876544 DOI: 10.1016/j.bioactmat.2021.01.030] [Citation(s) in RCA: 142] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 01/11/2021] [Accepted: 01/27/2021] [Indexed: 02/07/2023] Open
Abstract
Metals and alloys, including stainless steel, titanium and its alloys, cobalt alloys, and other metals and alloys have been widely used clinically as implant materials, but implant-related infection or inflammation is still one of the main causes of implantation failure. The bacterial infection or inflammation that seriously threatens human health has already become a worldwide complaint. Antibacterial metals and alloys recently have attracted wide attention for their long-term stable antibacterial ability, good mechanical properties and good biocompatibility in vitro and in vivo. In this review, common antibacterial alloying elements, antibacterial standards and testing methods were introduced. Recent developments in the design and manufacturing of antibacterial metal alloys containing various antibacterial agents were described in detail, including antibacterial stainless steel, antibacterial titanium alloy, antibacterial zinc and alloy, antibacterial magnesium and alloy, antibacterial cobalt alloy, and other antibacterial metals and alloys. Researches on the antibacterial properties, mechanical properties, corrosion resistance and biocompatibility of antibacterial metals and alloys have been summarized in detail for the first time. It is hoped that this review could help researchers understand the development of antibacterial alloys in a timely manner, thereby could promote the development of antibacterial metal alloys and the clinical application.
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Affiliation(s)
- Erlin Zhang
- Key Lab. for Anisotropy and Texture of Materials, Education Ministry of China, School of Materials Science and Engineering, Northeastern University, Shenyang, 150819, China
- Research Center for Metallic Wires, Northeastern University, Shenyang, 110819, China
| | - Xiaotong Zhao
- Key Lab. for Anisotropy and Texture of Materials, Education Ministry of China, School of Materials Science and Engineering, Northeastern University, Shenyang, 150819, China
| | - Jiali Hu
- Key Lab. for Anisotropy and Texture of Materials, Education Ministry of China, School of Materials Science and Engineering, Northeastern University, Shenyang, 150819, China
| | - Ruoxian Wang
- Key Lab. for Anisotropy and Texture of Materials, Education Ministry of China, School of Materials Science and Engineering, Northeastern University, Shenyang, 150819, China
| | - Shan Fu
- Key Lab. for Anisotropy and Texture of Materials, Education Ministry of China, School of Materials Science and Engineering, Northeastern University, Shenyang, 150819, China
| | - Gaowu Qin
- Key Lab. for Anisotropy and Texture of Materials, Education Ministry of China, School of Materials Science and Engineering, Northeastern University, Shenyang, 150819, China
- Research Center for Metallic Wires, Northeastern University, Shenyang, 110819, China
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Additive Manufacturing of Titanium-Based Implants with Metal-Based Antimicrobial Agents. METALS 2021. [DOI: 10.3390/met11030453] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Due to increasing bacterial resistance to antibiotics, surface coatings of medical devices with antimicrobial agents have come to the fore. These surface coatings on medical devices were basically thin coatings that delaminated from the medical devices due to the fluid environment and the biomechanical activities associated with in-service implants. The conventional methods of manufacturing have been used to alloy metal-based antimicrobial (MBA) agents such as Cu with Ti6Al4V to enhance its antibacterial properties but failed to produce intricate shapes. Additive manufacturing technology, such as laser powder bed fusion (LPBF), could be used to produce the Ti6Al4V–xCu alloy with intricate shapes to enhance osseointegration, but have not been successful for texturing the surfaces of the Ti6Al4V–xCu samples at the nanoscale.
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7
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Alqattan M, Peters L, Alshammari Y, Yang F, Bolzoni L. Antibacterial Ti-Mn-Cu alloys for biomedical applications. Regen Biomater 2021; 8:rbaa050. [PMID: 33732496 PMCID: PMC7947594 DOI: 10.1093/rb/rbaa050] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 09/25/2020] [Accepted: 10/25/2020] [Indexed: 12/02/2022] Open
Abstract
Titanium alloys are common biomedical materials due to their biocompatibility and mechanical performance. However, titanium alloys are expensive and, unless surface treated, generally cannot prevent surgical infections related to bacteria which can damage the integrity of the implant. In this study, new titanium alloys were developed via powder metallurgy and the addition of manganese and copper, respectively, aiming to limit the manufacturing costs and induce new functionality on the materials including antibacterial response. The addition of manganese and copper to titanium significantly changes the behaviour of the Ti-Mn-Cu alloys leading to the successful stabilization of the beta titanium phase, great refinement of the typical lamellar structure, and achievement of materials with low level of porosity. Consequently, it is found that the mechanical performance and the antibacterial efficacy are enhanced by the addition of a higher amount of alloying elements. The manufactured Ti-Mn-Cu alloys fulfil the requirements for structural biomedical implants and have antibacterial response making them potential candidates for permanent medical implants.
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Affiliation(s)
| | - Linda Peters
- The University of Waikato, Hamilton, New Zealand
| | | | - Fei Yang
- The University of Waikato, Hamilton, New Zealand
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Vilardell AM, Takezawa A, du Plessis A, Takata N, Krakhmalev P, Kobashi M, Albu M, Kothleitner G, Yadroitsava I, Yadroitsev I. Mechanical behavior of in-situ alloyed Ti6Al4V(ELI)-3 at.% Cu lattice structures manufactured by laser powder bed fusion and designed for implant applications. J Mech Behav Biomed Mater 2020; 113:104130. [PMID: 33049622 DOI: 10.1016/j.jmbbm.2020.104130] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 09/22/2020] [Accepted: 10/01/2020] [Indexed: 10/23/2022]
Abstract
In the present study, cellular lattice structures for implant applications are reported for the first-time incorporating copper directly by in-situ alloying in the laser powder bed fusion process. The aim to incorporate 3 at.% Cu into Ti6Al4V(ELI) is selected for improved antibacterial properties while maintaining appropriate mechanical properties. Previously, topologically optimized Ti6Al4V(ELI) lattice structures were successfully designed, manufactured and studied for implant applications. The development of a new alloy produced by in-situ alloying of elemental powder mixture of Ti6Al4V(ELI) and pure Cu powders was used here for the production of identical lattice structures with improved antibacterial properties. One of the same as-designed CAD models was used for the manufacturing of these lattices compared to previous work on pure Ti6Al4V(ELI) lattices, making direct comparison of mechanical properties possible. Similar manufacturability highlights the applicability of this alloying technique to other lattice designs. Microstructural characterization was performed by optical and electron microscopies, as well as microCT. Mechanical characterization was performed by means of compression tests and hardness measurements. Results showed that in-situ alloying with copper leads to the formation of localized Cu-rich regions, refinement of martensitic phase and the formation of CuTi2 intermetallic precipitates, which increased the hardness and strength of the material. Deviations in wall thickness between the as-designed and as-manufactured lattices led to anisotropy of the mechanical properties of the lattices. Higher compressive strength values were obtained when thicker walls were oriented along the loading direction. Nevertheless, alloying with Cu had a higher impact on the compressive strength of lattice structure than the wall thickness deviations. The direct in-situ alloying of copper in Ti6Al4V(ELI) is a promising route for direct manufacturing of antibacterial implants.
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Affiliation(s)
- A M Vilardell
- Karlstad University, Department of Engineering and Physics, Karlstad, SE-651 88, Sweden.
| | - A Takezawa
- Dept. of Applied Mechanics and Aerospace Engineering, School of Fundamental Science and Engineering, Waseda University, 59-311, 3-4-1 Okubo, Shinjuku-ku, Tokyo, 169-8555, Japan
| | - A du Plessis
- Research Group 3D Innovation, Stellenbosch University, Stellenbosch, 7602, South Africa
| | - N Takata
- Dept. of Materials Process Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - P Krakhmalev
- Karlstad University, Department of Engineering and Physics, Karlstad, SE-651 88, Sweden
| | - M Kobashi
- Dept. of Materials Process Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - M Albu
- Graz Centre for Electron Microscopy (ZFE), Steyrergasse 17-3, A-8010, Graz, Austria
| | - G Kothleitner
- Institute of Electron Microscopy and Nanoanalysis, Graz University of Technology, Steyrergasse 17-3, A-8010, Graz, Austria
| | - I Yadroitsava
- Dept. of Mechanical and Mechatronics Engineering, Central University of Technology, Bloemfontein, 9300, South Africa
| | - I Yadroitsev
- Dept. of Mechanical and Mechatronics Engineering, Central University of Technology, Bloemfontein, 9300, South Africa
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Xu W, Hou C, Mao Y, Yang L, Tamaddon M, Zhang J, Qu X, Liu C, Su B, Lu X. Characteristics of novel Ti-10Mo-xCu alloy by powder metallurgy for potential biomedical implant applications. Bioact Mater 2020; 5:659-666. [PMID: 32420516 PMCID: PMC7218015 DOI: 10.1016/j.bioactmat.2020.04.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 04/15/2020] [Accepted: 04/16/2020] [Indexed: 01/16/2023] Open
Abstract
When biomaterials are implanted in the human body, the surfaces of the implants become favorable sites for microbial adhesion and biofilm formation, causing peri-implant infection which frequently results in the failure of prosthetics and revision surgery. Ti-Mo alloy is one of the commonly used implant materials for load-bearing bone replacement, and the prevention of infection of Ti-Mo implants is therefore crucial. In this study, bacterial inhibitory copper (Cu) was added to Ti-Mo matrix to develop a novel Ti-Mo-Cu alloy with bacterial inhibitory property. The effects of Cu content on microstructure, tensile properties, cytocompatibility, and bacterial inhibitory ability of Ti-Mo-Cu alloy were systematically investigated. Results revealed that Ti-10Mo-1Cu alloy consisted of α and β phases, while there were a few Ti2Cu intermetallic compounds existed for Ti-10Mo-3Cu and Ti-10Mo-5Cu alloys, in addition to α and β phases. The tensile strength of Ti-10Mo-xCu alloy increased with Cu content while elongation decreased. Ti-10Mo-3Cu alloy exhibited an optimal tensile strength of 1098.1 MPa and elongation of 5.2%. Cytocompatibility study indicated that none of the Ti-10Mo-xCu alloys had a negative effect on MC3T3-E1 cell proliferation. Bacterial inhibitory rates against S. aureus and E. coli increased with the increase in Cu content of Ti-10Mo-xCu alloy, within the ranges of 20-60% and 15-50%, respectively. Taken together, this study suggests that Ti-10Mo-3Cu alloy with high strength, acceptable elongation, excellent cytocompatibility, and the bacterial inhibitory property is a promising candidate for biomedical implant applications.
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Affiliation(s)
- Wei Xu
- Beijing Advanced Innovation Center for Materials Genome Engineering, State Key Laboratory for Advanced Metals and Materials, Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing, China
- Institute of Orthopaedic & Musculoskeletal Science, University College London, Royal National Orthopaedic Hospital, Stanmore, HA7 4LP, UK
- Bristol Dental School, University of Bristol, Bristol, BS1 2LY, UK
| | - Chenjin Hou
- Beijing Advanced Innovation Center for Materials Genome Engineering, State Key Laboratory for Advanced Metals and Materials, Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing, China
| | - Yuxuan Mao
- Center for Health Science and Engineering, Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology, School of Materials Science and Engineering, Hebei University of Technology, Tianjin, 300130, China
| | - Lei Yang
- Center for Health Science and Engineering, Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology, School of Materials Science and Engineering, Hebei University of Technology, Tianjin, 300130, China
| | - Maryam Tamaddon
- Institute of Orthopaedic & Musculoskeletal Science, University College London, Royal National Orthopaedic Hospital, Stanmore, HA7 4LP, UK
| | - Jianliang Zhang
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Xuanhui Qu
- Beijing Advanced Innovation Center for Materials Genome Engineering, State Key Laboratory for Advanced Metals and Materials, Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing, China
| | - Chaozong Liu
- Institute of Orthopaedic & Musculoskeletal Science, University College London, Royal National Orthopaedic Hospital, Stanmore, HA7 4LP, UK
| | - Bo Su
- Bristol Dental School, University of Bristol, Bristol, BS1 2LY, UK
| | - Xin Lu
- Beijing Advanced Innovation Center for Materials Genome Engineering, State Key Laboratory for Advanced Metals and Materials, Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing, China
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Abstract
Ever since their introduction, nickel–titanium (NiTi) alloys have continued to revolutionize the field of endodontics. They have considerable advantages over the conventional stainless steel file in terms of mechanical properties. However, despite of their superior mechanical properties, NiTi alloys still pose some risk of fracture. Consequently, there has been considerable research conducted to investigate the mechanisms behind the occurrence of these procedural errors. Since the last decade, different proprietary processing procedures have been introduced to further improve the mechanical properties of NiTi alloys. These treatments include thermal, mechanical, electropolishing, and recently introduced electric discharge machining. The main purpose of these treatments is to impart a more martensitic phase into the files at normal body temperature, so that the maximum advantage of flexibility can be obtained. These heat-treated instruments also possess improved cyclic fatigue resistance when compared to conventional NiTi alloys. NiTi alloys can be subclassified as the instruments mainly containing austenitic phase (conventional NiTi, M-wire, R-phase), and those containing martensitic phase (controlled memory wire, ProTaper Gold, and Vortex Blue). Instruments based on austenitic alloys possess superelastic properties due to the stress-induced martensitic transformation. Contrary to this, martensitic alloys can easily be deformed due to phase transformation, and they can demonstrate the shape memory effect when heated. This review discusses the different phase transformations and heat treatments that the NiTi instruments undergo.
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11
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Bolzoni L, Yang F. Development of Cu-bearing powder metallurgy Ti alloys for biomedical applications. J Mech Behav Biomed Mater 2019; 97:41-48. [PMID: 31096149 DOI: 10.1016/j.jmbbm.2019.05.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 05/03/2019] [Accepted: 05/08/2019] [Indexed: 11/29/2022]
Abstract
Cu-bearing Ti alloys could be used as structural biomedical materials where the releasing of Cu ions is beneficial to lower infection incidences associated with surgical implants. The manufacturing of these alloys via powder metallurgy techniques can lower the production costs. In this study three ternary Cu-bearing Ti-xAl-yCu alloys were produced using conventional powder metallurgy. The mechanical properties increase with the amount of alloying elements. Samples of each composition were also forged to clarify the effect of subjecting them to hot deformation. Forging the samples improved the strength of the alloys due to the reduction of porosity and the refinement of the microstructural features. It is found that Ti-2Al-1Cu is the most ductile, Ti-6Al-4Cu is the strongest and Ti-10Al-5Cu has a purely elastic behaviour. Some of these powder metallurgy Ti-xAl-yCu alloys have better overall mechanical behaviour than their cast counterparts and therefore are valuable alternative to produce medical and dental implants with improved properties and reduced cost.
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Affiliation(s)
- L Bolzoni
- WaiCAM, School of Engineering, The University of Waikato, Private Bag 3105, 3240, Hamilton, New Zealand.
| | - F Yang
- WaiCAM, School of Engineering, The University of Waikato, Private Bag 3105, 3240, Hamilton, New Zealand
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12
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Peng C, Zhang S, Sun Z, Ren L, Yang K. Effect of annealing temperature on mechanical and antibacterial properties of Cu-bearing titanium alloy and its preliminary study of antibacterial mechanism. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2018; 93:495-504. [PMID: 30274083 DOI: 10.1016/j.msec.2018.08.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 06/23/2018] [Accepted: 08/06/2018] [Indexed: 01/20/2023]
Abstract
Cu-bearing titanium alloys are designed and studied as a novel medical metal material with antibacterial function. However, the addition of Cu would affect the mechanical properties of titanium alloy more or less, especially the ductility, despite its excellent antibacterial property. Thus, the aim of this study was to optimize the heat treatment for Cu-bearing titanium alloys in order to achieve a balance of satisfactory mechanical, antibacterial and other properties. In this study, Ti6Al4V-5 wt% Cu alloy was fabricated, and then different annealing treatments with various heating temperatures (700-910 °C) were employed on the alloy. The effects of heating temperature on microstructure evolution, mechanical properties, corrosion resistance and antibacterial performance of Ti6Al4V-5Cu alloy were systematically studied. It was found that annealing at 740 °C for Ti6Al4V-5Cu alloy showed the best comprehensive properties of high strength, excellent ductility, corrosion resistance and antibacterial performance. The Ti2Cu phases played an important role in the mechanical property and antibacterial performance for Ti6Al4V-5Cu alloy, and bacteria preferred to adhere on the α phase region, rather than the β or globule Ti2Cu region.
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Affiliation(s)
- Cong Peng
- School of Materials Science of Engineering, University of Science and Technology of China, Shenyang 110016, China; Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
| | - Shuyuan Zhang
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
| | - Ziqing Sun
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
| | - Ling Ren
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China.
| | - Ke Yang
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
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Yamanoglu R, Efendi E, Kolayli F, Uzuner H, Daoud I. Production and mechanical properties of Ti-5Al-2.5Fe-xCu alloys for biomedical applications. ACTA ACUST UNITED AC 2018; 13:025013. [PMID: 29061917 DOI: 10.1088/1748-605x/aa957d] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
In this study, the mechanical, antibacterial properties and cell toxicity response of Ti-5Al2.5Fe alloy with different copper contents were investigated. The alloys were prepared by high-energy ball milling using elemental Ti, Al, Fe, and Cu powders and consolidated by a uniaxial vacuum hot press. Staphylococcus aureus strain ATCC 29213 and Escherichia coli strain ATCC 25922 were used to determine the antibacterial properties of the sintered alloys. The in vitro cytotoxicity of the samples was evaluated with HeLa (ATTC, CCL-2) cells using thiazolyl blue tetrazolium bromide. The mechanical behavior of the samples was determined as a function of hardness and bending tests and analyzed by scanning electron microscopy, energy dispersive x-ray spectroscopy, optical microscopy and x-ray diffraction (XRD). The results showed that the Cu content significantly improved the antibacterial properties. Cu addition prevented the formation of E. coli and S. aureus colonies on the surface of the samples. All samples exhibited very good cell biocompatibility. The alloys with different copper contents showed different mechanical properties, and the results were correlated by microstructural and XRD analyses in detail. Our results showed that Cu has a great effect on the Ti5Al2.5Fe alloy and the alloy is suitable for biomedical applications with enhanced antibacterial activity.
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Affiliation(s)
- Ridvan Yamanoglu
- Kocaeli University, Engineering Faculty, Metallurgical and Materials Engineering Department, Kocaeli, Turkey
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Ounsi HF, Nassif W, Grandini S, Salameh Z, Neelakantan P, Anil S. Evolution of Nickel-titanium Alloys in Endodontics. J Contemp Dent Pract 2017; 18:1090-1096. [PMID: 29109327 DOI: 10.5005/jp-journals-10024-2181] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
UNLABELLED To improve clinical use of nickel-titanium (NiTi) endodontic rotary instruments by better understanding the alloys that compose them. A large number of engine-driven NiTi shaping instruments already exists on the market and newer generations are being introduced regularly. While emphasis is being put on design and technique, manufacturers are more discreet about alloy characteristics that dictate instrument behavior. Along with design and technique, alloy characteristics of endodontic instruments is one of the main variables affecting clinical performance. Modification in NiTi alloys is numerous and may yield improvements, but also drawbacks. Martensitic instruments seem to display better cyclic fatigue properties at the expense of surface hardness, prompting the need for surface treatments. On the contrary, such surface treatments may improve cutting efficiency but are detrimental to the gain in cyclic fatigue resistance. Although the design of the instrument is vital, it should in no way cloud the importance of the properties of the alloy and how they influence the clinical behavior of NiTi instruments. CLINICAL SIGNIFICANCE Dentists are mostly clinicians rather than engineers. With the advances in instrumentation design and alloys, they have an obligation to deal more intimately with engineering consideration to not only take advantage of their possibilities but also acknowledge their limitations.
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Affiliation(s)
- Hani F Ounsi
- Department of Endodontics, Faculty of Dental Medicine Lebanese University, Beirut, Lebanon; Department of Endodontics and Restorative Dentistry, Siena University, Siena, Italy, e-mail:
| | - Wadih Nassif
- Department of Prosthodontics, Faculty of Dental Medicine Lebanese University, Beirut, Lebanon
| | - Simone Grandini
- Department of Endodontics and Restorative Dentistry, Siena University, Siena, Italy
| | - Ziad Salameh
- Department of Research, Faculty of Dental Medicine, Lebanese University, Beirut, Lebanon
| | - Prasanna Neelakantan
- Department of Endodontology, Faculty of Dentistry, The University of Hong Kong, Hong Kong
| | - Sukumaran Anil
- Department of Dental Health, Dental Biomaterials Research Chair, College of Applied Medical Sciences, King Saud University Riyadh, Kingdom of Saudi Arabia
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Takahashi M, Kikuchi M, Takada Y. Mechanical properties and microstructures of dental cast Ti-6Nb-4Cu, Ti-18Nb-2Cu, and Ti-24Nb-1Cu alloys. Dent Mater J 2017; 35:564-70. [PMID: 27477221 DOI: 10.4012/dmj.2015-354] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The mechanical properties -tensile strength, yield strength, elongation after fracture, and Vickers hardness- and alloy phases of the dental cast alloys Ti-6%Nb-4%Cu, Ti-18%Nb-2%Cu, and Ti-24%Nb-1%Cu were investigated. Ti-6%Nb-4%Cu consisted of a single α-phase, while Ti-18%Nb-2%Cu and Ti-24%Nb-1%Cu consisted of α- and β-phases. The tensile strengths, yield strengths, and hardnesses of these alloys were higher than those of Ti-5%Cu and Ti-30%Nb; however, their breaking elongations were smaller. These differences in the mechanical properties are attributable to solid-solution strengthening or to precipitation strengthening by the dual-phase (α+β) structure. Thus, Ti-Nb-Cu alloys are suitable for use in high-strength dental prostheses, such as implantretained superstructures and narrow-diameter implants.
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Affiliation(s)
- Masatoshi Takahashi
- Division of Dental Bioaterials, Tohoku University Graduate School of Dentistry
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Yu HN, Hsu HC, Wu SC, Hsu SK, Ho WF. Structure and Mechanical Properties of As-Cast Ti-5Sn-xMo Alloys. MATERIALS 2017; 10:ma10050458. [PMID: 28772820 PMCID: PMC5458995 DOI: 10.3390/ma10050458] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 04/23/2017] [Accepted: 04/24/2017] [Indexed: 11/16/2022]
Abstract
Ti-5Sn-xMo (x = 0, 1, 3, 5, 7.5, 10, 12.5, 15, 17.5, and 20 wt %) alloys were designed and prepared for application as implant materials with superior mechanical properties. The results demonstrated that the crystal structure and mechanical properties of Ti-5Sn-xMo alloys are highly affected by their Mo content. The as-cast microstructures of Ti-5Sn-xMo alloys transformed in the sequence of phases α' → α″ → β, and the morphologies of the alloys changed from a lath structure to an equiaxed structure as the Mo content increased. The α″-phase Ti-5Sn-7.5Mo (80 GPa) and β-phase Ti-5Sn-10Mo (85 GPa) exhibited relatively low elastic moduli and had excellent elastic recovery angles of 27.4° and 37.8°, respectively. Furthermore, they exhibited high ductility and moderate strength, as evaluated using the three-point bending test. Search for a more suitable implant material by this study, Ti-5Sn-xMo alloys with 7.5 and 10 wt % Mo appear to be promising candidates because they demonstrate the optimal combined properties of microhardness, ductility, elastic modulus, and elastic recovery capability.
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Affiliation(s)
- Hsing-Ning Yu
- Department of Surgery, Division of Orthopaedics, Zuoying Branch of Kaohsiung Armed Forces General Hospital, Kaohsiung 81342, Taiwan.
| | - Hsueh-Chuan Hsu
- Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taichung 40601, Taiwan.
| | - Shih-Ching Wu
- Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taichung 40601, Taiwan.
| | - Shih-Kuang Hsu
- Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taichung 40601, Taiwan.
| | - Wen-Fu Ho
- Department of Chemical and Materials Engineering, National University of Kaohsiung, Kaohsiung 81148, Taiwan.
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Zhang E, Ren J, Li S, Yang L, Qin G. Optimization of mechanical properties, biocorrosion properties and antibacterial properties of as-cast Ti-Cu alloys. ACTA ACUST UNITED AC 2016; 11:065001. [PMID: 27767022 DOI: 10.1088/1748-6041/11/6/065001] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Ti-Cu sintered alloys have shown good antibacterial abilities. However, the sintered method (powder metallurgy) is not convenient to produce devices with a complex structure. In this paper, Ti-Cu alloys with 2.0, 3.0 and 4.0 wt.% Cu were prepared in an arc melting furnace and subjected to different heat treatments: solid solution and ageing, to explore the possibility of preparing an antibacterial Ti-Cu alloy by a casting method and to examine the effect of Cu content. Phase identification was conducted on an XRD diffraction meter, and the microstructure was observed by a metallographic microscope, a scanning electron microscope (SEM) with energy disperse spectroscopy (EDS) and transmission electron microscopy (TEM). Microhardness and the compressive property of Ti-Cu alloys were tested, and the corrosion resistance and antibacterial activity were assessed in order to investigate the effect of the Cu content. Results showed that the as-cast Ti-Cu alloys exhibited a very low antibacterial rate against Staphylococcus aureus (S. aureus). Heat treatment improved the antibacterial rate significantly, especially after a solid and ageing treatment (T6). Antibacterial rates as high as 90.33% and 92.57% were observed on Ti-3Cu alloy and Ti-4Cu alloy, respectively. The hardness, the compressive yield strength, the anticorrosion resistance and the antibacterial rate of Ti-Cu alloys increased with an increase of Cu content in all conditions. It was demonstrated that homogeneous distribution and a fine Ti2Cu phase played a very important role in the mechanical property, anticorrosion and antibacterial properties. Furthermore, it should be pointed out that the Cu content should be at least 3 wt.% to obtain good antibacterial properties (>90% antibacterial rate) as well as satisfactory mechanical properties.
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Affiliation(s)
- Erlin Zhang
- Key Laboratory for Anisotropy and Texture of Materials, Education Ministry of China, School of Materials Science and Engineering, Northeastern University, Shenyang 110819, People's Republic of China
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Effect of extrusion processing on the microstructure, mechanical properties, biocorrosion properties and antibacterial properties of Ti-Cu sintered alloys. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 69:760-8. [PMID: 27612770 DOI: 10.1016/j.msec.2016.07.051] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 07/12/2016] [Accepted: 07/19/2016] [Indexed: 11/23/2022]
Abstract
Ti-Cu sintered alloys, Ti-Cu(S) alloy, have exhibited good anticorrosion resistance and strong antibacterial properties, but low ductility in previous study. In this paper, Ti-Cu(S) alloys were subjected to extrusion processing in order to improve the comprehensive property. The phase constitute, microstructure, mechanical property, biocorrosion property and antibacterial activity of the extruded alloys, Ti-Cu(E), were investigated in comparison with Ti-Cu(S) by X-ray diffraction (XRD), optical microscopy (OM), scanning electronic microscopy (SEM) with energy disperse spectroscopy (EDS), mechanical testing, electrochemical testing and plate-count method in order to reveal the effect of the extrusion process. XRD, OM and SEM results showed that the extrusion process did not change the phase constitute but refined the grain size and Ti2Cu particle significantly. Ti-Cu(E) alloys exhibited higher hardness and compressive yield strength than Ti-Cu(S) alloys due to the fine grain and Ti2Cu particles. With the consideration of the total compressive strain, it was suggested that the extrusion process could improve the ductility of Ti-Cu alloy(S) alloys. Electrochemical results have indicated that the extrusion process improved the corrosion resistance of Ti-Cu(S) alloys. Plate-count method displayed that both Ti-Cu(S) and Ti-Cu(E) exhibited strong antibacterial activity (>99%) against S. aureus. All these results demonstrated that hot forming processing, such as the extrusion in this study, refined the microstructure and densified the alloy, in turn improved the ductility and strength as well as anticorrosion properties without reduction in antibacterial properties.
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Faria AC, Rodrigues RC, Rosa AL, Ribeiro RF. Experimental titanium alloys for dental applications. J Prosthet Dent 2014; 112:1448-60. [DOI: 10.1016/j.prosdent.2013.12.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Revised: 12/19/2013] [Accepted: 12/31/2013] [Indexed: 11/15/2022]
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Zhang B, Wang B, Wang Y, Li L, Zheng Y, Liu Y. Development of Ti-Ag-Fe ternary titanium alloy for dental application. J Biomed Mater Res B Appl Biomater 2011; 100:185-96. [DOI: 10.1002/jbm.b.31937] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2010] [Revised: 06/06/2011] [Accepted: 06/25/2011] [Indexed: 11/11/2022]
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Augusta Orsi I, Raimundo LB, Luiz Bezzon O, Antonio de Arruda Nóbilo M, Kuri SE, Rovere CAD, Oliveira Pagnano V. Evaluation of Anodic Behavior of Commercially Pure Titanium in Tungsten Inert Gas and Laser Welds. J Prosthodont 2011; 20:628-31. [DOI: 10.1111/j.1532-849x.2011.00771.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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22
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Wear resistance of experimental titanium alloys for dental applications. J Mech Behav Biomed Mater 2011; 4:1873-9. [PMID: 22098886 DOI: 10.1016/j.jmbbm.2011.06.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Revised: 06/04/2011] [Accepted: 06/06/2011] [Indexed: 11/23/2022]
Abstract
The present study evaluated microstructure, microhardness and wear resistance of experimental titanium alloys containing zirconium and tantalum. Alloys were melted in arc melting furnace according to the following compositions: Ti-5Zr, Ti-5Ta and Ti-5Ta-5Zr (%wt). Hemispheres and disks were obtained from wax patterns that were invested and cast by plasma. Microstructures were evaluated using optical microscopy and X-ray diffraction (XRD) analysis and also Vickers microhardness was measured. Hemispherical samples and disks were used for 2-body wear tests, performed by repeated grinding of the samples. Wear resistance was assessed as height loss after 40,000 cycles. The data were compared using ANOVA and post-hoc Tukey test. Ti-5Zr presented a Widmanstätten structure and the identified phases were α and α' while Ti-5Ta and Ti-5Ta-5Zr presented α, β, α' and α" phases, but the former presented a lamellar structure, and the other, acicular. The microhardness of Ti-5Zr was significantly greater than other materials and cp Ti presented wear resistance significantly lower than experimental alloys. It was concluded that wear resistance was improved when adding Ta and Zr to titanium and Zr increased microhardness of Ti-5Zr alloy.
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Bauer J, Cella S, Pinto MM, Filho LER, Reis A, Loguercio AD. Effect of argon purity on mechanical properties, microstructure and fracture mode of commercially pure (cp) Ti and Ti-6Al-4V alloys for ceramometal dental prostheses. Biomed Mater 2009; 4:065002. [DOI: 10.1088/1748-6041/4/6/065002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Koike M, Cai Z, Oda Y, Hattori M, Fujii H, Okabe T. Corrosion behavior of cast Ti-6Al-4V alloyed with Cu. J Biomed Mater Res B Appl Biomater 2005; 73:368-74. [PMID: 15744719 DOI: 10.1002/jbm.b.30225] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
It has recently been found that alloying with copper improved the inherently poor grindability and wear resistance of titanium. This study characterized the corrosion behavior of cast Ti-6Al-4V alloyed with copper. Alloys (0.9 or 3.5 mass % Cu) were cast with the use of a magnesia-based investment in a centrifugal casting machine. Three specimen surfaces were tested: ground, sandblasted, and as cast. Commercially pure titanium and Ti-6Al-4V served as controls. Open-circuit potential measurement, linear polarization, and potentiodynamic cathodic polarization were performed in aerated (air + 10% CO(2)) modified Tani-Zucchi synthetic saliva at 37 degrees C. Potentiodynamic anodic polarization was conducted in the same medium deaerated by N(2) + 10% CO(2). Polarization resistance (R(p)), Tafel slopes, and corrosion current density (I(corr)) were determined. A passive region occurred for the alloy specimens with ground and sandblasted surfaces, as for CP Ti. However, no passivation was observed on the as-cast alloys or on CP Ti. There were significant differences among all metals tested for R(p) and I(corr) and significantly higher R(p) and lower I(corr) values for CP Ti compared to Ti-6Al-4V or the alloys with Cu. Alloying up to 3.5 mass % Cu to Ti-6Al-4V did not change the corrosion behavior. Specimens with ground or sandblasted surfaces were superior to specimens with as-cast surfaces.
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Affiliation(s)
- Marie Koike
- Department of Developmental and Reconstructive Medicine, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, Sakamoto, Nagasaki, Japan.
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