论文部分内容阅读
制备两种主成分相同、微量组元含量不同的A1 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A1_3(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MgZn_2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%。
Two kinds of Al-Zn-Mg-Cu alloys with the same main composition and different content of trace elements were prepared. The effects of trace Sc on microstructure and texture during hot deformation and solid solution process were studied. Compared with the Zr-only alloy, the addition of a small amount of Zr, Sc alloy formed a smaller subgrain microstructure during the deformation process, the percentage of recrystallized grains decreased sharply after solid solution, and {011} <211> ( B) orientation is lower, and {112} <111> (C-) orientation is stronger. The reason is that after the addition of Zr and Sc, the particles of A1_3 (Sc, Zr) are homogenized and annealed in the grain boundary region, which precipitates grain boundaries and dislocations during the deformation and solid solution process. The interface provided by the subgrain can promote the precipitation of the MgZn_2 phase. The promoting effect and strengthening effect of substructures make the hardness of composite samples with addition of Sc and Zr increased by 11.3% compared with the addition of trace Zr.