1
|
Riley DM, Valdes JR, Einav I, Guillard F. Influence of shaped boundaries on propagating compaction bands in brittle porous media. Phys Rev E 2023; 108:064906. [PMID: 38243550 DOI: 10.1103/physreve.108.064906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 10/13/2023] [Indexed: 01/21/2024]
Abstract
The compression of brittle porous media can lead to the propagation of compaction bands. Although such localization phenomena have been observed in different geometries, including cuboidal and axisymmetric uniaxial compression, the role of boundary geometry on compaction features has yet to be explored, despite its relevance in geological conditions and industrial processes. To this end, we investigate the influence of shaped boundaries and inhomogeneous inclusions in a model brittle material made of puffed rice cereal. Using a variety of geometries, we show that compaction bands assume the shape of nearby boundaries, but return to a default planar form a distance away from them. Remarkably, the band aligns parallel to characteristic lines of minor principal stress obtained from a simple linear elastic model. The compelling correlation between the rotation of the principal stress directions and compaction band orientation holds implications for the geological interpretation of localized patterns in rocks and for comprehending the formation of weak planes in pharmaceutical tablets.
Collapse
Affiliation(s)
- David M Riley
- Particles and Grains Laboratory, School of Civil Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia and Geo-Innovations Research Laboratory, Department of Civil, Construction, and Environmental Engineering, San Diego State University, San Diego, California 92182, USA
| | - Julio R Valdes
- Particles and Grains Laboratory, School of Civil Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia and Geo-Innovations Research Laboratory, Department of Civil, Construction, and Environmental Engineering, San Diego State University, San Diego, California 92182, USA
| | - Itai Einav
- Particles and Grains Laboratory, School of Civil Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia and Geo-Innovations Research Laboratory, Department of Civil, Construction, and Environmental Engineering, San Diego State University, San Diego, California 92182, USA
| | - François Guillard
- Particles and Grains Laboratory, School of Civil Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia and Geo-Innovations Research Laboratory, Department of Civil, Construction, and Environmental Engineering, San Diego State University, San Diego, California 92182, USA
| |
Collapse
|
2
|
El-Eskandarany MS, Ali N, Al-Ajmi F, Banyan M. Phase Transformations from Nanocrystalline to Amorphous (Zr 70Ni 25Al 5) 100-xW x (x; 0, 2, 10, 20, 35 at. %) and Subsequent Consolidation. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:2952. [PMID: 34835716 PMCID: PMC8618145 DOI: 10.3390/nano11112952] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 10/26/2021] [Accepted: 10/28/2021] [Indexed: 02/07/2023]
Abstract
Glasses, which date back to about 2500 BC, originated in Mesopotamia and were later brought to Egypt in approximately 1450 BC. In contrast to the long-range order materials (crystalline materials), the atoms and molecules of glasses, which are noncrystalline materials (short-range order) are not organized in a definite lattice pattern. Metallic glassy materials with amorphous structure, which are rather new members of the advanced materials family, were discovered in 1960. Due to their amorphous structure, metallic glassy alloys, particularly in the supercooled liquid region, behave differently when compared with crystalline alloys. They reveal unique and unusual mechanical, physical, and chemical characteristics that make them desirable materials for many advanced applications. Although metallic glasses can be produced using different techniques, many of these methods cannot be utilized to produce amorphous alloys when the system has high-melting temperature alloys (above 1500 °C) and/or is immiscible. As a result, such constraints may limit the ability to fabricate high-thermal stable metallic glassy families. The purpose of this research is to fabricate metallic glassy (Zr70Ni25Al5)100-xWx (x; 0, 2, 10, 20, and 35 at. %) by cold rolling the constituent powders and then mechanically alloying them in a high-energy ball mill. The as-prepared metallic glassy powders demonstrated high-thermal stability and glass forming ability, as evidenced by a broad supercooled liquid region and a high crystallization temperature. The glassy powders were then consolidated into full-dense bulk metallic glasses using a spark plasma sintering technique. This consolidation method did not result in the crystallization of the materials, as the consolidated buttons retained their short-range order fashion. Additionally, the current work demonstrated the capability of fabricating very large bulk metallic glassy buttons with diameters ranging from 20 to 50 mm. The results indicated that the microhardness of the synthesized metallic glassy alloys increased as the W concentration increased. As far as the authors are aware, this is the first time this metallic glassy system has been reported.
Collapse
Affiliation(s)
- M. Sherif El-Eskandarany
- Nanotechnology and Applications Program, Energy and Building Research Center, Kuwait Institute for Scientific Research, Safat 13109, Kuwait; (N.A.); (F.A.-A.); (M.B.)
| | | | | | | |
Collapse
|
3
|
Chen S, Wang J, Xia L, Wu Y. Deformation Behavior of Bulk Metallic Glasses and High Entropy Alloys under Complex Stress Fields: A Review. ENTROPY 2019; 21:e21010054. [PMID: 33266770 PMCID: PMC7514161 DOI: 10.3390/e21010054] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Revised: 01/05/2019] [Accepted: 01/09/2019] [Indexed: 12/17/2022]
Abstract
The plastic deformation of bulk metallic glasses (BMGs) depends significantly on applied stress states, and more importantly, in practical applications of BMGs as structural materials, they always deform under complex stress fields. The understanding of deformation behavior of BMGs under complex stress fields is important not only for uncovering the plastic deformation mechanisms of BMGs, but also for developing BMG components with excellent mechanical performance. In this article, we briefly summarize the recent research progress on the deformation behavior of BMGs under complex stress fields, including the formation and propagation of shear bands, tunable macroscopic plasticity, and serrated plastic flows. The effect of complex stress fields on the plastic deformation mechanisms of BMGs is discussed from simple stress gradient to tailored complex stress fields. The deformation behavior of high entropy alloys (HEAs) under complex stress states has also been discussed. Challenges, potential implications and some unresolved issues are proposed.
Collapse
Affiliation(s)
- Shunhua Chen
- School of Mechanical Engineering, Hefei University of Technology, Hefei 230009, China
- National-Local Joint Engineering Research Centre of Nonferrous Metals and Processing Technology, Hefei 230009, China
- Correspondence: (S.C.); (Y.W.)
| | - Jingyuan Wang
- School of Mechanical Engineering, Hefei University of Technology, Hefei 230009, China
| | - Lei Xia
- Laboratory for Microstructures, Shanghai University, Shanghai 200444, China
| | - Yucheng Wu
- National-Local Joint Engineering Research Centre of Nonferrous Metals and Processing Technology, Hefei 230009, China
- School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China
- Correspondence: (S.C.); (Y.W.)
| |
Collapse
|
4
|
Abstract
A mechanical model for waves impinging different configurations of multiple shear bands already formed in a ductile material, allows to analyze the ways in which dynamic interactions promote failure. It is shown that the presence of more than one shear band may lead to resonance and correspondent growth of a shear band or, conversely, to its annihilation. At the same time, multiple scattering may bring about focusing or, conversely, shielding from waves. The proposed mechanical modelling, represents the only way to analyze the fine micromechanisms governing material collapse, and discloses the complex interplay between dynamics and shear band growth or arrest.
Collapse
|
5
|
The role of configurational disorder on plastic and dynamic deformation in Cu 64Zr 36 metallic glasses: A molecular dynamics analysis. Sci Rep 2017; 7:40969. [PMID: 28102359 PMCID: PMC5244410 DOI: 10.1038/srep40969] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 12/13/2016] [Indexed: 11/25/2022] Open
Abstract
The varying degrees of configurational disorder in metallic glasses are investigated quantitatively by molecular dynamics studies. A parameter, the quasi-nearest atom, is used to characterize the configurational disorder in metallic glasses. Our observations suggest configurational disorder play a role in structural heterogeneity, plasticity and dynamic relaxations in metallic glasses. The broad configurational disorder regions distribution is the indicator of abundant potential deformation units and relaxations. Plastic flow, as well as relaxation, is believed to start at configurational disorder regions. The width of the shear bands and dynamic relaxations can then be regulated by the degree of configurational disorder regions in metallic glasses.
Collapse
|