从局域应力/应变视角理解异构金属材料的强韧化行为

The concurrent enhancement of strength and ductility is an unremitting pursuit in metallic material research. Recently, by deliberately controlling the spatial distribution of domains with substantially different mechanical properties, heterostructured architecture has overcome the limitation of strength-ductility synergy in metallic materials. Mainstream theories, such as hetero-deformation-induced hardening, strain partition, premature local necking delay, and interface affected zone, have provided crucial guidance for the designing of preferable heterostructured metallic materials. These theories suggest that the domains of heterostructured metallic materials present unique local stress and strain characteristics upon loading, accompanying deformation and fracture behaviors that deviate from the predictions of classical theories. In this study, the evolutions of local stress and strain during the early deformation, plastic deformation, and fracture stages of heterostructured metallic materials were reviewed. Moreover, interactions between deformation or fracture behaviors and local stress or strain as well as their effects on mechanical properties are summarized, presenting a new perspective for designing and developing high-performance heterostructured metallic materials.