Size effect of deformation nanotwin bundles on their strengthening and toughening in heterogeneous nanostructured Cu

作     者：YOU ZeSheng LUO ShuSen LU Lei YOU ZeSheng;LUO ShuSen;LU Lei

作者机构：Herbert Gleiter Institute of NanoscienceNanjing University of Science and TechnologyNanjing 210094China Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchChinese Academy of SciencesShenyang 110016China 

出 版 物：《Science China(Technological Sciences)》 (中国科学（技术科学英文版）)

年 卷 期：2021年第64卷第1期

页      面：23-31页

核心收录：

学科分类：07[理学] 070205[理学-凝聚态物理] 08[工学] 080501[工学-材料物理与化学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：supported by the National Key R&D Program of China(Grant No. 2017YFA0204403) financial support from the National Natural Science Foundation of China (Grant Nos. U1608257and 51931010) the Key Research Program of Frontier Science and the International Partnership Program (Grant No. GJHZ2029) Chinese Academy of Sciences,and Liaoning Revitalization Talents Program (Grant No. XLYC1802026) 

主　　题：fracture toughness nanotwins J-integral size effect toughening mechanism 

摘      要：Herein, we fabricated a heterogeneous nanostructured Cu with deformation nanotwin bundles(NTBs) embedded in a matrix of nanograins by means of dynamic plastic deformation at liquid nitrogen temperature. We conducted fracture mechanical measurements to investigate the effect of longitudinal length of the NTBs on their strengthening and toughening. Results suggest that an increase in the NTB length had a marginal influence on the tensile strength;however, it remarkably promoted both fracture initiation toughness and crack growth toughness. Longer NTBs are more effective not only in intrinsically enhancing crack tip plasticity by suppressing the strain localization and void nucleation but also in serving as crack bridges behind the crack front to extrinsically resist the fracture by shielding the crack tip.