Mechanical Properties and Deformation Mechanisms of Ti-15Nb-5Zr-4Sn-1Fe Alloy with Varying α Phase Fraction

An aged Al-5Zn-1.6Mg alloy with fine η' precipitates was grain refined to ~100 nm grain size by severe plastic deformation (SPD). Microstructure evolution during SPD and mechanical behaviour after SPD of the alloy were characterized by electron microscopy and tensile, compression as well as nanoindentation tests. The influence of η' precipitates on microstructure and mechanical properties of ultrafine grained Al-Zn-Mg alloy is discussed with respect to their effect on dislocation configurations and deformation mechanisms during processing of the alloy.

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Reverse Plasticity in Nanoindentation

MRS Proceedings ◽

10.1557/proc-1049-aa05-08 ◽

2007 ◽

Vol 1049 ◽

Author(s):

Yongjiang Huang ◽

Nursiani Indah Tjahyono ◽

Jun Shen ◽

Yu Lung Chiu

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Glass Transition ◽

Single Crystal ◽

Metallic Glasses ◽

Deformation Mechanisms ◽

Glass Transition Temperatures ◽

Loading Rates ◽

Nanoindentation Experiment ◽

Properties Of Materials

AbstractThis paper summarises our recent cyclic nanoindentation experiment studies on a range of materials including single crystal and nanocrystalline copper, single crystal aluminium and bulk metallic glasses with different glass transition temperatures. The unloading and reloading processes of the nanoindentation curves have been analysed. The reverse plasticity will be discussed in the context of plastic deformation mechanisms involved. The effect of loading rates on the mechanical properties of materials upon cyclic loading will also be discussed.

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The Effect of Heat Treatment on the Microstructure and Mechanical Properties of the Novel Low-Cost Ti-3Al-5Mo-4Cr-2Zr-1Fe Alloy

Materials ◽

10.3390/ma13173798 ◽

2020 ◽

Vol 13 (17) ◽

pp. 3798

Author(s):

Meng Sun ◽

Dong Li ◽

Yanhua Guo ◽

Ying Wang ◽

Yuecheng Dong ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Aging Time ◽

Volume Fraction ◽

Low Cost ◽

Solution Treatment ◽

Solution Temperature ◽

The Novel ◽

Α Phase ◽

The Cost

In order to reduce the cost of titanium alloys, a novel low-cost Ti-3Al-5Mo-4Cr-2Zr-1Fe (Ti-35421) titanium alloy was developed. The influence of heat treatment on the microstructure characteristics and mechanical properties of the new alloy was investigated. The results showed that the microstructure of Ti-35421 alloy consists of a lamina primary α phase and a β phase after the solution treatment at the α + β region. After aging treatment, the secondary α phase precipitates in the β matrix. The precipitation of the secondary α phase is closely related to heat treatment parameters—the volume fraction and size of the secondary α phase increase when increasing the solution temperature or aging time. At the same solution temperature and aging time, the secondary α phase became coarser, and the fraction decreased with increasing aging temperature. When Ti-35421 alloy was solution-treated at the α + β region for 1 h with aging surpassing 8 h, the tensile strength, yield strength, elongation and reduction of the area were achieved in a range of 1172.7–1459.0 MPa, 1135.1–1355.5 MPa, 5.2–11.8%, and 7.5–32.5%, respectively. The novel low-cost Ti-35421 alloy maintains mechanical properties and reduces the cost of materials compared with Ti-3Al-5Mo-5V-4Cr-2Zr (Ti-B19) alloy.

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Mechanical Properties and Deformation Mechanisms of Graphene Foams with Bi-Modal Sheet Thickness by Coarse-Grained Molecular Dynamics Simulations

Materials ◽

10.3390/ma14195622 ◽

2021 ◽

Vol 14 (19) ◽

pp. 5622

Author(s):

Shenggui Liu ◽

Mindong Lyu ◽

Chao Wang

Keyword(s):

Mechanical Properties ◽

Elastic Recovery ◽

Structural Connectivity ◽

High Stress ◽

Sheet Thickness ◽

Functional Materials ◽

Deformation Mechanisms ◽

Coarse Grained ◽

Graphene Sheets ◽

Graphene Foams

Graphene foams (GrFs) have been widely used as structural and/or functional materials in many practical applications. They are always assembled by thin and thick graphene sheets with multiple thicknesses; however, the effect of this basic structural feature has been poorly understood by existing theoretical models. Here, we propose a coarse-grained bi-modal GrF model composed of a mixture of 1-layer flexible and 8-layer stiff sheets to study the mechanical properties and deformation mechanisms based on the mesoscopic model of graphene sheets (Model. Simul. Mater. Sci. Eng. 2011, 19, 54003). It is found that the modulus increases almost linearly with an increased proportion of 8-layer sheets, which is well explained by the mixture rule; the strength decreases first and reaches the minimum value at a critical proportion of stiff sheets ~30%, which is well explained by the analysis of structural connectivity and deformation energy of bi-modal GrFs. Furthermore, high-stress regions are mainly dispersed in thick sheets, while large-strain areas mainly locate in thin ones. Both of them have a highly uneven distribution in GrFs due to the intrinsic heterogeneity in both structures and the mechanical properties of sheets. Moreover, the elastic recovery ability of GrFs can be enhanced by adding more thick sheets. These results should be helpful for us to understand and further guide the design of advanced GrF-based materials.

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Electronic and Mechanical Properties of Super Carbon Nanotube Networks

MRS Proceedings ◽

10.1557/proc-0963-q15-07 ◽

2006 ◽

Vol 963 ◽

Author(s):

Vitor R. Coluci ◽

Socrates O. Dantas ◽

Ado Jorio ◽

Douglas s Galvao

Keyword(s):

Mechanical Properties ◽

Carbon Nanotubes ◽

Carbon Nanotube ◽

Tight Binding ◽

Deformation Mechanisms ◽

Different Types ◽

Dynamics Simulations ◽

Walled Carbon Nanotubes ◽

Carbon Nanotube Networks ◽

Main Deformation

ABSTRACTEletronic and mechanical properties of ordered carbon nanotube networks are studied using molecular dynamics simulations and tight-binding calculations. These networks are formed by single walled carbon nanotubes (SWNT) regularly connected by junctions. The use of different types of junctions (“Y”-, “X”-like junctions, for example) allows the construction of networks with different symmetries. These networks can be very flexible and the elastic deformation was associated with two main deformation mechanisms (bending and stretching ) of the constituents SWNTs. Rolling up the networks, “super” carbon nanotubes can be constructed. These super-tubes share some of the main electronic features of the SWNT which form them but important changes are predicted (e.g. reduction of bandgap value). Simulations of their deformations under tensile stress have revealed that the super-tubes are softer than the corresponding SWNT and that their rupture occur in higher strain values.

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Mechanical properties and deformation mechanisms of Ti-3Al-5Mo-4.5 V alloy with varied β phase stability

Journal of Material Science and Technology ◽

10.1016/j.jmst.2018.04.004 ◽

2018 ◽

Vol 34 (12) ◽

pp. 2507-2514 ◽

Cited By ~ 11

Author(s):

Q. Xue ◽

Y.J. Ma ◽

J.F. Lei ◽

R. Yang ◽

C. Wang

Keyword(s):

Mechanical Properties ◽

Phase Stability ◽

Deformation Mechanisms ◽

Β Phase

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Influences of Solution Temperatures on Microstructure and Mechanical Properties of near α Titanium Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1035.89 ◽

2021 ◽

Vol 1035 ◽

pp. 89-95

Author(s):

Chao Tan ◽

Zi Yong Chen ◽

Zhi Lei Xiang ◽

Xiao Zhao Ma ◽

Zi An Yang

Keyword(s):

Mechanical Properties ◽

Titanium Alloy ◽

High Temperature ◽

Room Temperature ◽

Solution Temperature ◽

Vacuum Induction Melting ◽

Induction Melting ◽

Β Phase ◽

Α Phase ◽

New Type

A new type of Ti-Al-Sn-Zr-Mo-Si series high temperature titanium alloy was prepared by a water-cooled copper crucible vacuum induction melting method, and its phase transition point was determined by differential thermal analysis to be Tβ = 1017 °C. The influences of solution temperature on the microstructures and mechanical properties of the as-forged high temperature titanium alloy were studied. XRD results illustrated that the phase composition of the alloy after different heat treatments was mainly α phase and β phase. The microstructures showed that with the increase of the solution temperature, the content of the primary α phase gradually reduced, the β transformation structure increased by degrees, then, the number and size of secondary α phase increased obviously. The tensile results at room temperature (RT) illustrated that as the solution temperature increased, the strength of the alloy gradually increased, and the plasticity decreased slightly. The results of tensile test at 650 °C illustrated that the strength of the alloy enhanced with the increase of solution temperature, the plasticity decreased first and then increased, when the solution temperature increased to 1000 °C, the alloy had the best comprehensive mechanical properties, the tensile strength reached 714.01 MPa and the elongation was 8.48 %. Based on the room temperature and high temperature properties of the alloy, the best heat treatment process is finally determined as: 1000 °C/1 h/AC+650 °C/6 h/AC.

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Effect of Crystallographic Orientation on Nanoindentation Response of Fe3Si Single-Crystals

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.784.44 ◽

2018 ◽

Vol 784 ◽

pp. 44-48 ◽

Cited By ~ 1

Author(s):

Jaroslav Čech ◽

Petr Haušild ◽

Aleš Materna

Keyword(s):

Mechanical Properties ◽

Finite Element ◽

Shear Stress ◽

Contact Area ◽

Measured Data ◽

Deformation Mechanisms ◽

Spherical Indentation ◽

Indentation Modulus ◽

Slip Systems ◽

Correct Interpretation

Deformation mechanisms and mechanical properties of Fe3(wt.%)Si single crystal in two different orientations were investigated by spherical indentation. For correct interpretation of measured data and better understanding of the deformation mechanisms under the contact area, finite element simulations were carried out and resolved shear stress in available slip systems was computed. Pop-in behavior, differences in hardness, indentation modulus and shapes of residual imprints were observed and associated with different activation of slip.

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