Mobility of Edge Dislocations in the Basal‐Slip System of Zinc

The structure of low-angle boundaries in ZnGeP2crystals grown by the vertical Bridgman technique was studied using Borrmann X-ray topography. The slip systems of the dislocations in the boundaries were identified by studying the contrast rosettes generated by the Borrmann effect, in the region near the dislocation core. It was shown that the boundaries are of two types: type I consists of edge dislocations of the {1\overline{1}0}〈110〉 slip system, and type II of edge and mixed dislocations of the {010}〈100〉 slip system. The boundaries of both types, consisting of pure edge dislocations with lines along [001], are symmetrical tilt boundaries with [001] rotation axes. The misorientations generated by the boundaries were estimated to range between 2–20 and 1–40′′, respectively. Low-angle boundaries are thought to be formed by polygonization of dislocations, caused by thermoelastic stresses.

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Effect of basal and non-basal slip system activities on non-normality in hexagonal metal

The Proceedings of the Materials and Mechanics Conference ◽

10.1299/jsmemm.2016.os01-04 ◽

2016 ◽

Vol 2016 (0) ◽

pp. OS01-04

Author(s):

Yuichi TADANO

Keyword(s):

Slip System ◽

Basal Slip

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Revealing the Subsurface Basal 〈a〉 Dislocation Activity in Magnesium Through Lattice Rotation Analysis

Metallurgical and Materials Transactions A ◽

10.1007/s11661-020-05907-w ◽

2020 ◽

Vol 51 (9) ◽

pp. 4414-4421

Author(s):

Bijin Zhou ◽

Leyun Wang ◽

Wenjun Liu ◽

Xiaoqin Zeng ◽

Yanjun Li

Keyword(s):

Slip System ◽

Pole Figure ◽

Trace Analysis ◽

Basal Slip ◽

Lattice Rotation ◽

Burgers Vector ◽

Dislocation Activity ◽

Complementary Method ◽

Dislocation Behavior ◽

Basal Dislocation

Abstract A method was proposed in this study to reveal the subsurface basal dislocation activity in Mg-Y alloy and determine the corresponding Burgers vector. This is achieved by correlating the slip directions of dislocations to the lattice rotation represented by the {0001} pole figure. The identified basal slip system by this approach was verified by micro-Laue diffraction. This method can be applied as a complementary method to the conventional slip trace analysis to study the dislocation behavior of Mg alloys.

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Tem of Climb-Dissociated Dislocations in Sapphire

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055011 ◽

1982 ◽

Vol 40 ◽

pp. 554-555

Author(s):

K.P.D Lagerlof ◽

T.E. Mitchell ◽

A.H. Heuer

Keyword(s):

Basal Slip ◽

Break Up ◽

Diffusive Processes ◽

Edge Dislocations

1. Introduction. Dislocation dipoles consisting of perfect edge dislocations are formed during basal slip in sapphire. These dipoles are unstable and break up by several diffusive processes;

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Crystal Plasticity Analysis of Change in Active Slip Systems of α-Phase of Ti-6Al-4V Alloy under Cyclic Loading

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.725.183 ◽

2016 ◽

Vol 725 ◽

pp. 183-188

Author(s):

Yoshiki Kawano ◽

Tsuyoshi Mayama ◽

Ryouji Kondou ◽

Tetsuya Ohashi

Keyword(s):

Slip System ◽

Crystal Plasticity ◽

Basal Slip ◽

Slip Systems ◽

Cyclic Plastic ◽

Loading Direction ◽

Α Phase ◽

Primary Slip System ◽

Active Slip ◽

Plastic Loading

In this paper, we investigated changes in active slip systems of α-phase of Ti-6Al-4V alloy under a cyclic plastic loading using a crystal plasticity finite element method. In the analyses, a bicrystal model was employed, and the crystallographic orientations were set so as that prismatic <a> or basal slip system was the primary slip system in each grain. The results showed that there was a mechanism where the basal slip systems could reach the stage of activation under the cyclic plastic loading even though the condition was that the prismatic <a> slips initially operate. The reason for the activity changes was due to the changes in the incompatibility between the grains by the work hardening, and the effect of the incompatibility on activities of slip systems appeared even in the perpendicular arrangements of the grains to the loading direction.

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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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Pure-Shear Test for Investigation of Non-Basal Slip System Operation of Mg Alloy Single Crystal with and without Y

Journal of the Japan Institute of Metals and Materials ◽

10.2320/jinstmet.jaw201308 ◽

2013 ◽

Vol 77 (10) ◽

pp. 466-472 ◽

Cited By ~ 15

Author(s):

Takahiro Mineta ◽

Seiji Miura ◽

Toshiji Mukai ◽

Mikito Ueda ◽

Tetsuo Mohri

Keyword(s):

Slip System ◽

Single Crystal ◽

Basal Slip ◽

Shear Test ◽

Pure Shear ◽

Alloy Single Crystal ◽

Mg Alloy ◽

System Operation

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Ca-induced Plasticity in Magnesium Alloy: EBSD Measurements and VPSC Calculations

Crystals ◽

10.3390/cryst10020067 ◽

2020 ◽

Vol 10 (2) ◽

pp. 67 ◽

Cited By ~ 4

Author(s):

Umer Masood Chaudry ◽

Kotiba Hamad ◽

Jung-Gu Kim

Keyword(s):

Shear Stress ◽

Magnesium Alloy ◽

Slip System ◽

Basal Slip ◽

Room Temperature ◽

Prismatic Slip ◽

Slip Systems ◽

Electron Backscattered Diffraction ◽

Self Consistent ◽

Critical Resolved Shear Stress

In the present work, Ca-induced plasticity of AZ31 magnesium alloy was studied using electron backscattered diffraction (EBSD) measurements supported by viscoplastic self-consistent (VPSC) calculations. For this purpose, alloy samples were stretched to various strains (5%, 10%, and 15%) at room temperature and a strain rate of 10−3 s−1. The EBSD measurements showed a higher activity of non-basal slip system (prismatic slip) as compared to that of tension twins. The VPSC confirmed the EBSD results, where it was found that the critical resolved shear stress of the various slip systems and their corresponding activities changed during the stretching of the alloy samples.

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