Al-Zn对称成分合金不连续析出组织的再结晶

采用光学显微镜、扫描电镜和透射电镜研究了Al 4 0 %Zn(摩尔分数 )二元合金的不连续析出细片层组织在冷轧后重新加热时所发生的再结晶。根据加热过程中的显微组织变化 ,确定了该合金再结晶的形核及长大机制。结果发现 ,再结晶的 2种机制为非典型形核长大机制的连续粗化和典型形核长大机制的不连续粗化 ,后者又分为在团域界面、滑移带等处发生的以变形储能为主要驱动力的粗化和在变形量很小区域发生的以界面能为主要驱动力的粗化。

Recrystallization of cold deformed discontinuous precipitation microstructure in symmetrical Al-Zn alloy

Recrystallization of cold rolled discontinuous precipitation microstructure which has fine lamellar structure in a Al-40%Zn (mole fraction) binary alloy was investigated by optical microscopy, SEM and TEM. According to the microstructural evolution during the heating process, the nucleation and growth of recrystallization of this alloy was determined. It is found that there are two types of recrystallization: continuous coarsening (CC) which is non-typical nucleation and growth mechanism and discontinuous coarsening (DC) which is typical nucleation and growth one. The latter can be divided into coarsening mainly driven by deformation stored energy at colony boundaries and slip bands and the one mainly driven by boundary energy in the area without much deformation.