Abstract
The mechanical properties of crystalline materials can be efficiently optimized using a hierarchical twinned structure.Conventional deformation mechanisms for coherent E3 boundaries generally involve three basic models:cross-slip,partial dislocation step,and full dislocation step.In this study,we report a novel deformation mechanism that allows the co-existence of twin-separation,phase transformations,grain rotation,and cracking,around a triple junction of twin boundaries in a hierarchical twinned high-entropy alloy.The deformation mechanisms in the reference high-entropy alloy(Fe-30Mn-10Co-10Cr at.％)were investigated using LAADF-STEM.The triple junction of the hierarchical twinned structure gradually deformed during in-situ strain and showed mechanisms significantly different from that observed in the purely twinned structures.These new mechanisms are referred to as"novel synergetic deformation mech-anisms of hierarchical twin boundaries".Understanding the fundamental mechanisms of the hierarchical twin boundaries under deformation could assist the design of strong and ductile bulk materials with hierarchical twinned structure.
基金项目
European Research Council under the EU's 7th Framework Programme(FP7/2007-2013/ERC)
European Research Council under the EU's 7th Framework Programme(290998)
National Natural Science Foundation of ChinaNSFC(11872380)
Natural Science Foundation of Hunan Province(2019JJ50750)
Natural Science Foundation of Hunan Province(2020JJ3043)
NETL
NSTL
维普
万方数据