Skin layer of A380 aluminium alloy die castings and its blistering during solution treatment  

作　　者：Zihao Yuan Zhipeng Guo S.M.Xionga 

机构地区：[1]School of Materials Science and Engineering,Tsinghua University,Beijing,100084,China [2]State Key Laboratory of Automobile Safety and Energy,Tsinghua University,Beijing,100084,China

出　　处：《Journal of Materials Science & Technology》2019年第9期1906-1916,共11页材料科学技术（英文版）

基　　金：the National Natural Science Foundation of China (Grant No. 51775297) for financial support

摘　　要：Skin layer is a characteristic microstructure of aluminium die castings, which would effect the surface blistering during solution treatment. In this study, the microstructures of skin layer were investigated by the methods of optical microscope (OM), scanning electron microscope (SEM) and electron probe microanalyzer (EPMA). High resolution X-ray CT was used to compare the skin layer with normal surface before and after solution treatment. With the aid of computational fluid dynamics (CFD), the formation mechanism of the skin layer was discussed based on microstructure distribution, solute segregation, porosity distribution and surface blistering. The results suggested that the skin layer is related to a succession of complex processes before the filling process finished. Pore clusters or laminar defects would be formed in skin layers during solution treatm ent and cause severe surface blistering.Skin layer is a characteristic microstructure of aluminium die castings, which would effect the surface blistering during solution treatment. In this study, the microstructures of skin layer were investigated by the methods of optical microscope(OM), scanning electron microscope(SEM) and electron probe microanalyzer(EPMA). High resolution X-ray CT was used to compare the skin layer with normal surface before and after solution treatment. With the aid of computational fluid dynamics(CFD), the formation mechanism of the skin layer was discussed based on microstructure distribution, solute segregation, porosity distribution and surface blistering. The results suggested that the skin layer is related to a succession of complex processes before the filling process finished. Pore clusters or laminar defects would be formed in skin layers during solution treatment and cause severe surface blistering.

关 键 词：SKIN layer Die CASTINGS Solution treatment BLISTERING 

分 类 号：TG[金属学及工艺]