相变温度附近热处理对Mg97Zn1Y2合金组织演化的影响  

Effect of the Isothermal Heat Treatment near the Phase Transition Temperature on Microstructure Evolution of Mg97Zn1Y2 Alloy

作　　者：万迪庆[1] 叶舒婷[1] 胡莹琳 利助民 韩明[1] 李丽丽[1] 陈朝霞[1] Wan Diqing;Ye Shuting;Hu Yinglin;Li Zhumin;Han Ming;Li Lili;Chen Zhaoxia(East China Jiaotong University,Nanchang 330013,China)

机构地区：[1]华东交通大学,江西南昌330013

出　　处：《稀有金属材料与工程》2018年第9期2869-2874,共6页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51361010;51665012);江西省教育厅科技项目(150536)

摘　　要：研究了相变温度附近不同热处理方法对含长周期结构Mg97Zn1Y2合金的组织影响,并对演变机理进行了探讨。主要研究结论如下:进行500℃固溶处理时,随着时间的增加,晶界处的LPSO相部分固溶进基体中,同时部分LPSO相杆状化;采用等温热处理时Mg97Zn1Y2合金中的枝晶组织转变为球状晶,当合金保温温度从540℃升到600℃时,合金组织尺寸由大→小→大的顺序变化,即经过了粗化、分离及球化至最后粗化3个过程。在等温热处理温度为575℃的组织大致演变趋势为:枝晶态→不规则球形+块状→球形状,当保温时间15min,其组织即可变为均匀、圆整的球状晶。Effects of isothermal heat treatment temperature near the phase transition temperature and holding time on the microstructures of Mg97Zn1Y2 alloys with LPSO structure were studied.Meanwhile,the evolution mechanism was discussed.The results show that the long-period structure has a tendency of growing with the increase of time,when the temperature of solid-solution treatment is 500 ℃.It is found that the dendrite structure of Mg97Zn1Y2 alloy can be transformed into spherical crystal by isothermal heat treatment.When the insulation temperature range of the alloy is from 540 ℃ to 600 ℃,the size of microstructures changes in the order of large-small-large,in other words,it is coarsened,separated and spheroidized,and finally coarsened.The trend of microstructure evolution is from dendritic to irregular spherical and massive,and finally to spherical at the isothermal heat treatment temperature of 575 ℃.When the holding time is 15 min,its microstructures are rounded spherical crystal.

关 键 词：等温热处理 Mg97Zn1Y2合金 长周期结构 

分 类 号：TG146.22[一般工业技术—材料科学与工程]