热处理对ZK60镁合金组织与力学性能的影响

摘要

研究固溶和时效热处理工艺对铸态ZK60镁合金显微组织与力学性能的影响.结果表明,当固溶处理条件为400 ℃下保温10 h、时效处理温度为150.c时,ZK60合金中析出相随时效时间的延长而增加,直至30 h.当时效温度升至200℃时,析出相体积分数在时效时间为15～20 h时达到最大值.室温拉伸实验表明,高密度第二相析出物有利于提高合金的强度和靼性.优化的热处理工艺条件为400℃固溶10 h随后于150℃时效30 h,得到的镁合金兼具有高的强度与塑性综合性能.%The microstructure and mechanical properties of ZK60 Mg alloy were investigated under different solution treatments and artificial aging conditions. When as-cast ZK60 alloy was solution treated at 400 ℃ for 10 h and artificially aged at 150 ℃, the volume fraction of precipitates increased with the aging time up to 30 h. When the as-cast ZK60 alloy was solution treated at 400 ℃ for 10 h and artificially aged at 200 ℃ for 15-20 h, the volume fraction of precipitates reached a peak value. Tensile test at room temperature showed that a high density of the second phase precipitates was beneficial to improving the strength and elongation. Solution treatment at 400 ℃ for 10 h and artificial aging at 150 ℃ for 30 h is considered the optimum heat treatment condition to obtain a good combination of strength and ductility.