Evolution of Microstructure and Mechanical Properties of Semi-Solid Squeeze Cast A356.2 Aluminum Alloy during Heat Treatment

Semi-solid squeeze casting (SS-SC) is a new processing technology which combines semi-solid processing (SSP) and squeeze casting (SC). In this process, semi-solid slurry fills mold by using its rheological property and solidifies under high pressure. It has several advantages, such as stable filling, small heat impact to the mold, low cost, high density and excellent mechanical properties of castings, which receives more and more attention. The microstructure of castings provided by SS-SC is quite different from that of casting provided by conventional SC in as-cast condition, which leads to differences in the evolution of microstructure and mechanical properties in heat treatment process. In this study, A356.2 aluminum alloys castings were provided by both SS-SC and conventional SC respectively. The evolution of microstructure and mechanical properties of castings during heat treatment was investigated to obtain the best mechanical properties of semi-solid squeeze castings. Keywords:Microstructure, Mechanical properties, Heat treatment, A356 alloy, Semi-Solid Squeeze Casting