Deformation Behavior of Sapphire Via the Prismatic Slip System

The stress-induced martensitic transformation and slip deformation behavior were investigated by the compression test with anin-situobservation in a Ti-6Mo-10Al (mol %) alloy single crystal. Owing to the stress-induced martensitic transformation from the parent β phase to the α′′ martensite phase, the single crystal of α′′ martensite without internal twinnings was successfully obtained at room temperature. By further compression, the slip deformation occurred in the single crystal of α′′ martensite. The operated slip system in the α′′ martensite was analyzed by the two face trace analyses, and the slip direction was determined to be []o.

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Effect of Slip System Transition on the Deformation Behavior of Mg-Al Alloy: Internal Variable Based Approach

Transactions of Materials Processing ◽

10.5228/kspp.2004.13.6.535 ◽

2004 ◽

Vol 13 (6) ◽

pp. 535-539 ◽

Cited By ~ 1

Keyword(s):

Slip System ◽

Deformation Behavior ◽

Internal Variable ◽

Al Alloy ◽

System Transition

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Reducing Yield Asymmetry between Tension and Compression by Fabricating ZK60/WE43 Bimetal Composites

Materials ◽

10.3390/ma13010249 ◽

2020 ◽

Vol 13 (1) ◽

pp. 249

Author(s):

Kangning Zhao ◽

Dexing Xu ◽

Xiao Song ◽

Yingzhong Ma ◽

Hongxiang Li ◽

...

Keyword(s):

Deformation Mechanism ◽

Deformation Behavior ◽

Extrusion Direction ◽

Stress Transfer ◽

Prismatic Slip ◽

Special Method ◽

Interface Microstructure ◽

Tension And Compression ◽

Deformation Modes ◽

Bimetal Composite

In this study ZK60/WE43 bimetal composite rods were manufactured by a special method of hot diffusion and co-extrusion. Interface microstructure, deformation mechanism, and yield asymmetry between tension and compression for the composite rods were systematically investigated. It was observed that the salient deformation mechanism of the ZK60 constituent was {10-12}<−1011> extension twinning in compression and prismatic slip in tension, and different deformation modes resulted in yield asymmetry between tension and compression. In contrast, the WE43 constituent tends to be more isotropic due to grain refinement, texture weakening, solid-solution and precipitation strengthening, which were deformed via basal slip, prismatic slip, and {10-12}<−1011> extension twinning in both tension and compression. Surprisingly, it was found that yield asymmetry between tension and compression for the ZK60/WE43 composite rods along the extrusion direction was effectively reduced with a compression-to-tension ratio of ~0.9. The strongly bonded interface acting as a stress transfer medium for the ZK60 sleeve and WE43 core exhibited the coordinated deformation behavior. This finding provides an effective method to decrease the yield asymmetry between tension and compression in the extruded magnesium alloys.

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Influence of Grain Boundary on Activation of Slip Systems in Magnesium: Crystal Plasticity Analysis

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.695 ◽

2010 ◽

Vol 654-656 ◽

pp. 695-698 ◽

Cited By ~ 2

Author(s):

Tsuyoshi Mayama ◽

Tetsuya Ohashi ◽

Kenji Higashida

Keyword(s):

Grain Boundary ◽

Slip System ◽

Crystal Plasticity ◽

Crystal Orientation ◽

Basal Slip ◽

Prismatic Slip ◽

Shear Stresses ◽

Slip Systems ◽

Analysis Method ◽

Pyramidal Slip

Crystal plasticity finite element analysis method considering the accumulation of geometrically necessary (GN) dislocations was applied to monotonic loading of pure magnesium bi-crystal. The deformation mechanisms considering in the present analysis method are basal slip <a>, prismatic slip <a>, 1st order pyramidal slip <a>, 2nd order pyramidal slip <a+c> and tensile twinning <a+c>. Tensile twinning is incorporated into crystal plasticity analysis assuming that twinning plane and direction of shear by twinning are equivalent to slip plane and slip direction, respectively. Critical resolved shear stresses (CRSSs) for each slip system in the literatures were used. Analysis model is designed to investigate the influence of grain boundary on the activation of slip systems. That is, one grain consisting of bi-crystal (grain A) had the crystal orientation whose Schmid factor for prismatic slip is 0.5. The crystal orientation of the other grain (grain B) was slightly deviated from that of grain A. The result of the calculation of tensile loading of the bi-crystal showed that both grains are deformed by the multiple slip of basal slip system, which resulted in the formation of GN dislocation bands.

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Estimation of micro-Hall-Petch coefficients for prismatic slip system in Mg-4Al as a function of grain boundary parameters

Acta Materialia ◽

10.1016/j.actamat.2021.117613 ◽

2021 ◽

pp. 117613

Author(s):

Mohsen Taheri Andani ◽

Aaditya Lakshmanan ◽

Veera Sundararaghavan ◽

John Allison ◽

Amit Misra

Keyword(s):

Grain Boundary ◽

Slip System ◽

Prismatic Slip

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Modeling the strength and ductility of magnesium alloys containing nanotwins

MRS Proceedings ◽

10.1557/opl.2013.499 ◽

2013 ◽

Vol 1513 ◽

Author(s):

S.B. Gorti ◽

B. Radhakrishnan

Keyword(s):

Slip System ◽

Magnesium Alloys ◽

Hydrostatic Stress ◽

Prismatic Slip ◽

Face Centered Cubic ◽

Crystallographic Slip ◽

Hcp Materials ◽

Image Position ◽

Fcc Materials ◽

Strength And Ductility

ABSTRACTMagnesium alloys have been receiving much attention recently as potential lightweight alternatives to steel for automotive and other applications, but the poor formability of these alloys at low temperatures has limited their widespread adoption for automotive applications. Recent work with face centered cubic (FCC) materials has shown that introduction of twins at the nanometer scale in ultra-fine grained FCC polycrystals can provide significant increase in strength with a simultaneous improvement in ductility. This objective of this work is to explore the feasibility of extending this concept to hexagonal close packed (HCP) materials, with particular focus on using this approach to increase both strength and ductility of magnesium alloys. A crystal plasticity based finite element (CPFE) model is used to study the effect of varying the crystallographic texture and the spacing between the nanoscale twins on the strength and ductility of HCP polycrystals. Deformation of the material is assumed to occur by crystallographic slip, and in addition to the basal and prismatic slip systems, slip is also assumed to occur on the {1 0 $\bar 1$ 1} planes that are associated with compression twins in these materials. The slip system strength of the pyramidal systems containing the nanotwins is assumed to be much lower than the strength of the other systems, which is assumed to scale with the spacing between the nanotwins. The CPFE model is used to compute the stress-strain response for different microstrucrutral parameters, and a criterion based on a critical slip system shear strain and a critical hydrostatic stress is used to compute the limiting strength and ductility, with the ultimate goal of identifying the texture and nanotwin spacing that can lead to the optimum values for these parameters.

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Deformation Behavior of Electro-Deposited Pure Iron with Extremely High R-Value

Materials Science Forum ◽

10.4028/www.scientific.net/msf.702-703.291 ◽

2011 ◽

Vol 702-703 ◽

pp. 291-294 ◽

Cited By ~ 2

Author(s):

Natsuko Sugiura ◽

Naoki Yoshinaga

Keyword(s):

Slip System ◽

Deformation Behavior ◽

Pure Iron ◽

Tensile Deformation ◽

Fiber Texture ◽

Slip Lines ◽

Active Slip System ◽

R Value ◽

Deformation Surface ◽

Active Slip

Electro-deposited pure iron has a quite sharp and isotropic <111>//ND fiber texture and a needle-shaped grain elongated in ND. This pure iron shows an r-value exceeding 7, which is difficult to explain from the texture alone. In this study the deformation behavior of electro-deposited pure iron was investigated to reveal the mechanism behind the extremely high r-value. The post-deformation surface slip lines indicated that the particular <110> plane slips, which are perpendicular to ND, exclusively act in the specimen. The tensile deformation caused by this slip system does not require any decrease in thickness, hence the extraordinary high r-value is mainly attributable to this limitation of the active slip system. Presumably, the needle-shaped microstructure affected the limitation of the slip system.

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In-situ EBSD characterization of deformation behavior of primary alpha phase in Ti-6Al-4V

MATEC Web of Conferences ◽

10.1051/matecconf/202032111053 ◽

2020 ◽

Vol 321 ◽

pp. 11053

Author(s):

Wansong Li ◽

Shigeto Yamasaki ◽

Masatoshi Mitsuhara ◽

Hideharu Nakashima

Keyword(s):

Tensile Test ◽

Deformation Behavior ◽

Alpha Phase ◽

Electron Back Scatter Diffraction ◽

Prismatic Slip ◽

Kernel Average Misorientation ◽

Rotation Rates ◽

Average Rotation

Uniaxial tension experiments and electron back-scatter diffraction were performed on a bimodal Ti-6Al-4V alloy to study the deformation behavior of primary hcp-Ti (αp). It was found that the obtained tensile strength and elongation of the studied Ti-6Al-4V from the in-situ tensile test are higher than of which derived from the regular tensile test. The strain could be accommodated by the activation of slip systems and by grain rotations during the deformation. The prismatic slip is the primary slip mode of αp. According to kernel average misorientation analysis, we found that the dislocations mainly distributed near grain boundaries and subgrain boundaries, and partially located around slip lines. Calculated rotation angles and average rotation rates show that the rotation heterogeneity occurred among grains and subgrains.

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Anisotropy of the Microstructure and Tensile Properties in Ti-5Al-5Mo-5V-1Cr-1Fe near β Titanium Alloy during Hot Rolling and Heat Treatment

Metals ◽

10.3390/met8110904 ◽

2018 ◽

Vol 8 (11) ◽

pp. 904

Author(s):

Xiaoyong Zhang ◽

Yaping Mei ◽

Yaping Lv ◽

Chao Chen ◽

Kechao Zhou

Keyword(s):

Slip System ◽

Tensile Properties ◽

Prismatic Slip ◽

Texture Intensity ◽

Anisotropic Strength ◽

Α Phase ◽

Heat Treated ◽

Texture Type ◽

Hot Rolled ◽

The Relationship

Ti-55511 billet with the acicular α initial microstructure was hot rolled (HR sample) and then heat treated (HR+HT sample) at 750 °C. The effects of HR and HT on the anisotropy of microstructure, texture, and tensile properties were investigated. The tensile results show that there are obvious anisotropic tensile properties between RD and TD. The anisotropic elongation of HR sample is related to the morphology of α phase. After HR, the acicular α is parallel to RD. As for RD specimen, the transgranular propagation of microcrack passing through the acicular α phase leads to the ductile fracture, thus showing the higher ductility than TD specimen. While the intergranular propagation of microcrack passing by the equiaxed α phase in TD specimen causes the brittle fracture. The anisotropic strength of HR sample depends on the relationship among texture type of α phase, slip system, and loading direction. The maximum texture intensity at TD leads to the easy activation of basal slip system in RD and that of prismatic slip system in TD, and then causes the lower strength of RD specimen than TD specimen. After HT, the decreased anisotropy of elongation and strength can be attributed to the increased α size and the decreased texture intensity of α phase. These results demonstrate that anisotropic tensile properties mainly depend on the morphology and texture of α phase.

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