高铁356铝合金半固态等温处理过程中的组织演变  

Microstructure evolution of 356 aluminum alloy with high Fe content during semi-solid isothermal treatment

作　　者：林波[1] 李浩宇 许锐 张卫文[2] 肖华强[1] 李少波[1] LIN Bo;LI Hao-yu;XU Rui;ZHANG Wei-wen;XIAO Hua-qiang;LI Shao-bo(School of Mechanical Engineering, GuiZhou University, Guiyang 550025, China;School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640, China)

机构地区：[1]贵州大学机械工程学院,贵州贵阳550025 [2]华南理工大学机械与汽车工程学院,广东广州510640

出　　处：《材料热处理学报》2018年第6期55-61,共7页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(51704084);中国博士后基金(2017M623068);贵州省自然科学基金[黔科合基础(2016)1026];贵州省教育厅青年科技人才成长项目(黔教合KY字[2017]101)

摘　　要：采用显微组织观察、定量金相分析、扫描差热分析、扫描电镜、X射线衍射研究高铁356铝合金在半固态等温处理过程中的组织演变。结果表明：高铁含量356铝合金合适的半固态等温处理工艺为590℃下保温60 min,此时α（Al）晶粒较圆整,晶粒尺寸为89μm,形状因子为0.75,液相比率为40%;半固态等温技术可以使β-Fe富铁相由长针状转变为细小短棒状,这主要是归因于高温下富铁相的溶解及断裂。The microstructure evolution of 356 aluminum alloy with high iron content during semi-solid isothermal treatment was studied by means of microstructure observation,quantitative metallographic analysis,differential scanning calorimetry,scanning electron microscopy and X-ray diffraction. The results show that the optimal semi-solid isothermal treatment process for the 356 aluminum alloy with high Fe content is thermal insulation at 590 ℃ for 60 min. After that the α（ Al） grain will turn rounded,and have the grain size of 89 μm,shape factor of 0. 75 and the liquid phase fraction of 40%. The semi-solid isothermal treatment can change the Fe-rich β-Fe phase from the long needle-like to the fine short rod-like,mainly attributed to the dissolution and breakage of the iron-rich intermetallics at high temperature.

关 键 词：半固态等温处理 356铝合金 富铁相 

分 类 号：TG146.2[一般工业技术—材料科学与工程]