热处理对Mg-Y-Zn-Ag稀土镁合金长周期组织结构的影响  

Effect of heat treatment on long-period microstructure of Mg-Y-Zn-Ag rare earth magnesium alloy

作　　者：杜金星[1] 华建社[1] 赵旭[1] 袁超 Du Jinxing;Hua Jianshe;Zhao Xu;Yuan Chao(School of Metallurgical Engineering,Xi＇an University of Architecture and Technology,Xi＇an Shaanxi 710055,China)

机构地区：[1]西安建筑科技大学冶金工程学院

出　　处：《金属热处理》2018年第11期173-177,共5页Heat Treatment of Metals

摘　　要：研究了不同Ag含量的Mg-Y-Zn-Ag稀土镁合金经过热处理后的组织和力学性能的变化。结果发现,在稀土镁合金中添加Ag后,经过热处理后,晶粒尺寸明显细化,合金中LPSO相（长周期堆垛有序结构）细化显著,同时Ag2Mg和MgAg相分布更加均匀。通过500℃×24 h固溶和200℃×20 h时效后,合金的力学性能提升显著。当合金中加入Ag含量为3%时（质量分数,下同）,合金性能最佳,抗拉强度和伸长率分别为194 MPa和7. 1%。Ag含量为2%时,500℃固溶处理24 h,合金达到了最高显微硬度为81. 2 HV0. 2,对比铸态原始合金显微硬度提升显著。Microstructure and mechanical properties of Mg-Y-Zn-Ag rare earth magnesium alloy after different heat treatments were studied.The results show that with addition of Ag,the grain size and LPSO phase （long-period stacking order structure） of the Mg-Y-Zn-Ag rare earth magnesium alloy are significantly refined,and the distribution of Ag2Mg and MgAg phases in the alloy is more uniform. After 500 ℃ ×24 h solution treatment and 200 ℃ × 20 h aging,the mechanical properties of the alloy are improved significantly. When the content of Ag is 3% （mass fraction,the same below）,the alloy has the best properties,the tensile strength and elongation are 194 MPa and 7. 1%,respectively. When the content of Ag is 2%,and treated at 500 ℃ for 24 h,the maximum microhardness of the alloy is 81. 2 HV0. 2,which is significantly improved compared with that of the as-cast alloy.

关 键 词：稀土镁合金 AG Y 微观组织 力学性能 热处理 

分 类 号：TG156[金属学及工艺—热处理]