We conducted molecular dynamics (MD) simulations of tension and compression along the <112> direction and MD simulations of compression along the <110> and <111> directions on nanolaminated graphene/...We conducted molecular dynamics (MD) simulations of tension and compression along the <112> direction and MD simulations of compression along the <110> and <111> directions on nanolaminated graphene/Cu (NGCu) composites to investigate the effects of the incorporated graphene and the deformation mechanisms related to the loading direction. The deformation behavior and the defect structures were found to be strongly dependent on the loading conditions. An asymmetric tension-compression deformation behavior was thus found in graphene/Cu nanolaminates under the <112> loading, which was dominated by stacking faults and deformation twins formed by dislocation slide under tension and compression, respectively. High density and ordered nanotwins were formed at the graphene/Cu interfaces. Two different formation mechanisms of the twins were found under the <112> compression, and the nucleated twins were easy to be thickened with the assistance of the graphene wrinkles. Multiple twins were formed under the <110> compression by the dislocation cross-slip. This study provides a way to introduce graphene reinforcement and twin boundary to Cu matrix composites and design nanotwinned graphene/Cu composites with excellent mechanical performance.展开更多
基金financial support from National Natural Science Foundation of China (grant nos. U1864208, 51603022, 11632004, 11802045)Fundamental Research Funds for the Central Universities (grant no. 106112017CDJXSYY0001)+3 种基金the Key Program for International Science and Technology Cooperation Projects of Ministry of Science and Technology of China (grant no. 2016YFE0125900)State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body (grant no. 31715007)the Postdoctoral Program for Innovative Talents of Chongqing (grant no. CQBX201804)the China Postdoctoral Science Foundation funded project (grant no. 2018M631058)
文摘We conducted molecular dynamics (MD) simulations of tension and compression along the <112> direction and MD simulations of compression along the <110> and <111> directions on nanolaminated graphene/Cu (NGCu) composites to investigate the effects of the incorporated graphene and the deformation mechanisms related to the loading direction. The deformation behavior and the defect structures were found to be strongly dependent on the loading conditions. An asymmetric tension-compression deformation behavior was thus found in graphene/Cu nanolaminates under the <112> loading, which was dominated by stacking faults and deformation twins formed by dislocation slide under tension and compression, respectively. High density and ordered nanotwins were formed at the graphene/Cu interfaces. Two different formation mechanisms of the twins were found under the <112> compression, and the nucleated twins were easy to be thickened with the assistance of the graphene wrinkles. Multiple twins were formed under the <110> compression by the dislocation cross-slip. This study provides a way to introduce graphene reinforcement and twin boundary to Cu matrix composites and design nanotwinned graphene/Cu composites with excellent mechanical performance.
