Explicit modeling of double twinning in AZ31 using crystal plasticity finite elements for predicting the mechanical fields for twin variant selection and fracture analyses

For conventional materials with solid solution, fatigue damage is often related to microplasticity and is largely sensitive to microstructure at different scales concerning dislocations, grains and textures. The present study focuses on slip bands activity and fatigue crack initiation with special attention on the influence of the size, the morphology and the crystal orientation of grains and their neighbours. The local configurations which favour - or prevent - crack initiation are not completely identified. In this work, the identification and the analysis of several crack initiation sites are performed using Scanning Electron Microscopy and Electron Back-Scattered Diffraction. Crystal plasticity finite elements simulation is employed to evaluate local microplasticity at the scale of the grains. One of the originality of this work is the creation of 3D meshes of polycrystalline aggregates corresponding to zones where fatigue cracks have been observed. 3D data obtained by serial-sectioning are used to reconstruct actual microstructure. The role of the plastic slip activity as a driving force for fatigue crack initiation is discussed according to the comparison between experimental observations and simulations. The approach is applied to 316L type austenitic stainless steels under low-cycle fatigue loading.

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A Study of Twin Variant Selection and Twin Growth in Titanium

Advanced Engineering Materials ◽

10.1002/adem.201100055 ◽

2011 ◽

Vol 13 (10) ◽

pp. 928-932 ◽

Cited By ~ 22

Author(s):

Lei Bao ◽

Christophe Schuman ◽

Jean-Sébastien Lecomte ◽

Marie-Jeanne Philippe ◽

Xiang Zhao ◽

...

Keyword(s):

Variant Selection ◽

Twin Variant ◽

Twin Growth

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{10–12} extension twin variant selection under a high train rate in AZ31 magnesium alloy during the plane strain compression

Vacuum ◽

10.1016/j.vacuum.2018.11.040 ◽

2019 ◽

Vol 160 ◽

pp. 279-285 ◽

Cited By ~ 6

Author(s):

Biwu Zhu ◽

Xiao Liu ◽

Chao Xie ◽

Yuanzhi Wu ◽

Jun Zhang

Keyword(s):

Magnesium Alloy ◽

Plane Strain ◽

Plane Strain Compression ◽

Az31 Magnesium Alloy ◽

Variant Selection ◽

Twin Variant

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Secondary twin variant selection in four types of double twins in titanium

Acta Materialia ◽

10.1016/j.actamat.2018.03.068 ◽

2018 ◽

Vol 152 ◽

pp. 58-76 ◽

Cited By ~ 34

Author(s):

Shun Xu ◽

Mingyu Gong ◽

Yanyao Jiang ◽

Christophe Schuman ◽

Jean-Sébastien Lecomte ◽

...

Keyword(s):

Variant Selection ◽

Twin Variant

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A new implementation of the spectral crystal plasticity framework in implicit finite elements

Mechanics of Materials ◽

10.1016/j.mechmat.2015.01.018 ◽

2015 ◽

Vol 84 ◽

pp. 114-126 ◽

Cited By ~ 56

Author(s):

Miroslav Zecevic ◽

Rodney J. McCabe ◽

Marko Knezevic

Keyword(s):

Finite Elements ◽

Crystal Plasticity

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Multiple twinning in pure hexagonal close-packed titanium

Journal of Applied Crystallography ◽

10.1107/s002188981302253x ◽

2013 ◽

Vol 46 (5) ◽

pp. 1397-1406 ◽

Cited By ~ 14

Author(s):

Lei Bao ◽

Yudong Zhang ◽

Christophe Schuman ◽

Jean-Sébastien Lecomte ◽

Marie-Jeanne Philippe ◽

...

Keyword(s):

Pure Titanium ◽

Variant Selection ◽

Hexagonal Close Packed ◽

Twin Variant ◽

Commercial Pure Titanium ◽

The Matrix ◽

Schmid Factor ◽

Sample Technique ◽

Multiple Twinning ◽

Selection Of

Commercial pure titanium (T40) was deformed in channel die compression by means of the split-sample technique in order to study multiple twinning. Particular attention was paid to the twin variant presentation and selection during multiple twinning. All possible misorientations, corresponding to the multiple twins arising from the combination of the {1 1 {\overline 2} 2} compression (C) twin, the {1 0 {\overline 1} 2} tension twin (T1) and the {1 1 {\overline 2} 1} tension twin (T2), were calculated with respect to the crystal basis of the matrix grain. All the multiple twin variants are partitioned into ten classes with the same crystallographically equivalent misorientation angle and axis. However, when the influence of twinning order is taken into account, the multiple twin variants are partitioned into 15 classes. Experimental results prove that the selection of twin variants (primary and secondary) is mainly governed by their macroscopic Schmid factor (SF). The normalized SF is more efficient at predicting variant selection. A twin formed in one grain can activate another twin in a neighbouring grain, provided that the angle between the two twinning planes does not exceed 20°.

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