中文摘要：

制备两种主成分相同、微量组元含量不同的Al--Zn--Mg--Cu合金, 研究了微量Sc对其热变形及固溶过程中微结构和织构的影响。与只添加Zr的合金比较, 复合添加微量Zr、Sc的合金在变形过程中形成了较小的亚晶组织, 固溶后再结晶百分数大幅降低, 且在固溶后{011}〈211〉（B--）取向的强度较低, {112}〈111〉（C--）取向的强度较强。其原因是, 添加Zr、Sc后形成的Al3（Sc, Zr）粒子均匀化退火后在晶界区域弥散析出, 对变形及固溶过程中晶界和位错的迁移产生了显著的阻碍。亚晶界提供的界面能促进了时效强化相MgZn2相的析出。这种促进作用和亚结构的强化作用使复合添加Sc、Zr的试样其硬度比只添加微量Zr提高了11.3%。

英文摘要：

Two alloys with the different components of trace elements were prepared, and the effects of Sc on the microstructure and texture of Al–Zn–Mg–Cu alloys during hot deformation and solution treatment were investigated. Comparing with the alloy containing only trace Zr, alloy containing trace Sc and trace Zr exhibited following characteristics： after hot deformation, there are smaller sub–grains in the alloy; after solution treatment, the alloy has lower recrystalization fraction, and the density of {011}〈211〉 （B–） orientation is stronger, while the density of {112}〈111〉 （C–） orientation is weaker. For this reason above all–Al3（Sc, Zr） particles formed during homogenization distribute uniformly in both inner grain areas and grain boundary areas, which severely prohibited the migration of dislocations and grain boundaries during hot deformation and solution treatment. Because of interfacial energy offered from sub–grain boundaries, the precipitation behavior of MgZn2 was promoted. The promotion and strengthen of sub–microstructural result in increase of the final hardness of alloys with the different components of trace elements by 11.3%.