文献类型：期刊文献

英文题名：Effect of high angle grain boundary on plastic deformation and fracture of micro-bicrystal copper: An in-situ SEM experimental and multiscale simulation study

作者：Wan, Shijia[1,2];Yu, Tianhao[1,2];Su, Ting[1,2];Yu, Tianchen[1,2];Yan, Yabin[1,2,3];Xuan, Fuzhen[1,2,3]

机构：[1]East China Univ Sci & Technol, Shanghai Key Lab Intelligent Sensing & Detect Tech, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Sch Mech & Power Engn, Key Lab Pressure Syst & Safety, Minist Educ, Shanghai 200237, Peoples R China;[3]Shanghai Collaborat Innovat Ctr High End Equipment, Shanghai 200237, Peoples R China

年份：2025

卷号：942

外文期刊名：MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

收录：;EI(收录号：20252618663673);WOS:【SCI-EXPANDED(收录号:WOS:001522836000002)】；

基金：Y. Yan thanks the support of National Natural Science Foundation of China (Grant No. 52275149) . F.Z. Xuan thanks the support of Science Fund for Creative Research Groups of the National Natural Science Foundation of China (Grant No. 52321002) and National Natural Sci-ence Foundation of China (Grant No. 51835003) .

语种：英文

外文关键词：Plastic deformation; Copper; Grain boundaries; In situ SEM experiment; Crystal plasticity; Molecular dynamics

摘要：The effect of the high angle grain boundary (HAGB) on the plastic deformation of microscale copper (Cu) was studied using micro-tensile specimens of Cu bicrystal with [7 2 7] and [1 1 11] orientations, respectively. In situ SEM observation revealed that deformation primarily concentrated in the [1 1 11] oriented grain, indicating that the presence of HAGBs restricted the transmission of dislocations between grains due to the mismatch in grain boundary slip. Crystal plasticity finite element simulations and extended finite element simulations revealed that the first activated slip system was (- 111)[0-11], rather than the system that was typically expected to dominate deformation due to its higher Schmid factor. This transition was attributed to the influence of HAGB geometry, which played a key role in determining the activation sequence of slip systems and led to crack initiation at the HAGB. To directly observe the nucleation and motion of dislocations, molecular dynamics simulations further confirmed that the HAGB acted as a favorable site for dislocation nucleation and effectively impeded dislocation transmission across the boundary. This work revealed the significant role of HAGBs in governing dislocation dynamics and crack initiation in microscale copper, providing valuable insights for improving the mechanical properties of bicrystalline materials.