异质纳米结构金属强化韧化机理研究进展

Progress in Strengthening and Toughening Mechanisms of Heterogeneous Nanostructured Metals

异质结构金属通常表现出传统均质材料无法企及的优异综合力学性能(如高强度、塑性和断裂韧性等),这主要源于其内部各组元间交互作用所产生的协同效应,包括应力/应变梯度、几何必需位错,以及独特的界面行为等。本文聚焦层状和纳米孪晶2类典型的异质纳米结构,回顾近期关于异质纳米结构金属的强化与韧化机制的研究进展,重点关注各异质组元性质、尺寸、界面以及加载方向等因素对宏观强化与韧化行为的影响规律。

Heterostructured metals typically exhibit excellent mechanical properties,such as high strength,plasticity,and fracture toughness,which are not present in conventional homogeneous materials.This is primarily due to the synergistic effects arising from the interactions between the internal components including the stress/strain gradients,geometrically necessary dislocations,and unique interfacial behavior.This study focuses on two typical heterogeneous nanostructures(laminated and nanotwinned)by reviewing the recent progress in their strengthening and toughening mechanisms.The analysis highlights the effects of the properties and sizes of the individual components,interfaces,and loading directions on the macroscopic strengthening and toughening behavior.