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

• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2019,（9）
• 页码范围: 1906-1916
• 页数: 11页
• 语种: 英文

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 treatment and cause severe surface blistering.