等温热处理对Mg-7Zn-0.3V合金半固态组织演变的影响  

Effects of isothermal heat treatment on semi-solid microstructural evolution of Mg-7Zn-0.3V alloy

作　　者：黄晓锋[1,2] 郭峰[1] 张玉[1] 杨健长 马亚杰 张乔乔 HUANG Xiao-feng;GUO Feng;ZHANG Yu;YANG Jian-chang;MA Ya-jie;ZHANG Qiao-qiao(State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals,Lanzhou University of Technology,Lanzhou 730050,China;Key Laboratory of Non-ferrous Metal Alloys and Processing,Ministry of Education,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,兰州730050 [2]兰州理工大学有色金属合金及加工教育部重点实验室,兰州730050

出　　处：《中国有色金属学报》2018年第8期1516-1522,共7页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(51464032);国家重点基础研究发展计划资助项目(2010CB635106)~~

摘　　要：通过半固态等温热处理,研究保温温度和保温时间对Mg-7Zn-0.3V镁合金把固态组织演变的影响。结果表明:保温温度和保温时间对Mg-7Zn-0.3V非枝晶组织的演变有重要的影响。提高保温温度或是延长保温时间,可以使Mg-7Zn-0.3V中的非枝晶组织转变为更加细小且分布均匀的球状颗粒。当保温温度过高或是保温时间过长时,半固态颗粒会出现合并和长大,其主要的演变机制与Ostwald熟化规律相符合。Mg-7Zn-0.3V合金的最佳等温热处理工艺是:保温温度605℃,保温时间40 min,非枝晶颗粒的平均尺寸为48.5μm,形状因子为1.26。The effects of remelting temperature and holding time on microstructural evolution of Mg-7Zn-0.3V magnesium alloy were investigated by semi-solid isothermal heat treatment. The results indicate that the holding temperature and holding time have significant effects on microstructural evolution of the Mg-7Zn-0.3V alloy during isothermal temperature process. By increasing the holding temperature or prolonging the holding time, the non-endritic structures in Mg-7Zn-0.3V can be transformed into smaller and more uniform spherical particles.When the holding temperature is too high or holding time is too long, the semi-solid particles will combine and grow up, the microstructural evolution mechanism is consistent with the rule of Ostwald ripening mechansim. The best parameters of isothermal heat treatment are 605 ℃ holding temperature and 40 min holding time, obtaining the semi-solid microstructure with the average partial size of 48.5 μm and the roundness of 1.26.

关 键 词：Mg-7Zn-0.3V镁合金 半固态等温处理 非枝晶组织 演变机理 

分 类 号：TG146.2[一般工业技术—材料科学与工程]