摘要
High-temperature and short-time(HTST)solution heat treatment combined with non-isothermal aging(NIA)was employed to regulate the microstructure and properties of Al−4.5Mg−2.0Zn−0.3Ag alloy.Results indicate that HTST solution heat treatment can not only retain partial deformation dislocations,but inhibit the recrystallization behavior and increase the proportion of low-angle grain boundaries(LAGBs).In the subsequent NIA process,HTST solution heat treatment combined with NIA is instrumental in restraining the degradation of dislocations and promoting precipitation of nano-scale T'-Mg_(32)(Al,Zn,Ag)49 phase,which improves the strength of the alloy greatly.In addition,a higher fraction of LAGBs and the discontinuous distribution of grain boundary precipitates caused by this novel technology meliorate the corrosion resistance of Al−4.5Mg−2.0Zn−0.3Ag alloy.
将高温短时(HTST)固溶处理与非等温时效(NIA)相结合,对Al-4.5Mg-2.0Zn-0.3Ag合金的显微组织与性能进行调控。结果表明,HTST固溶处理不仅保留了部分变形位错,而且能抑制再结晶行为,增加合金中小角度晶界(LAGBs)的比例。在随后的NIA过程中,HTST固溶处理结合NIA有助于抑制位错的退化,同时促进纳米尺度T'-Mg_(32)(Al,Zn,Ag)49相的析出,进而显著提高合金强度。此外,该新工艺中产生的较高比例LAGBs和不连续晶界析出相提高了Al-4.5Mg-2.0Zn-0.3Ag合金的耐蚀性。
基金
National Natural Science Foundation of China(Nos.52204400,52204401)
Natural Science Foundation of Hebei Province,China(No.E2022203033)。
