异质纳米结构金属强化韧化机理研究进展

卢磊, 赵怀智

Progress in Strengthening and Toughening Mechanisms of Heterogeneous Nanostructured Metals

LU Lei, ZHAO Huaizhi

图2 拉伸试样在动态塑性变形(DPD) Cu样品中的取样方式示意图,DPD Cu样品中典型的截面微观结构(显示纳米孪晶束(NT)镶嵌在纳米晶(NG)基体中),纳米孪晶/纳米晶混合结构Cu在不同加载方向下的拉伸工程应力-应变曲线,并与粗晶Cu进行对比,及Sample-P、Sample-N和Sample-I在1.0%宏观应变量下的局部全场应变分布图[45]

Fig.2 Sampling schematic diagram, cross-sectional microstructures, and stress-strain curves of DPD Cu (DPD—dynamic plastic deformation)[45] (a) schematic of the tensile specimens in the DPD disc and their orientations relative to the twin boundaries (TBs), i.e., parallel, normal, and 45° inclined to TBs, hereafter referred to as sample-P, sample-N, and sample-I, respectively (b, d) typical cross-sectional microstructures of DPD Cu, showing the nanotwins (NT) in the form of bundles embedded in a matrix of nanograins (NG) (c) tensile engineering stress-strain curves for the DPD processed heterogeneous nanostructured Cu and the coarse-grained (CG) Cu serve as a counterpart for comparison (e-g) local strain fields in sample-P (e), sample-N (f), and sample-I (g) at applied strain of 1.0%. The nanotwinned regions are denoted as NT, where the underscore indicated the direction parallel to TBs. The black dash lines indicate the position of the NT/NG interfaces. The tensile axes (TA) are represented by the double-headed arrows