AC4CH铝合金的挤压铸造研究

Squeezing Casting AC4CH Alloy

采用挤压铸造生产AC4CH合金铸件,研究了铸造压力、充型速度和充型距离对挤压铸件组织和性能的影响。挤压铸造AC4CH铝合金铸件组织由初生α-Al和共晶硅相组成,随着充型距离的增加,铸件显微组织明显细化。随着铸造压力和充型速度的增大,共晶相含量降低并且分布均匀。铸造压力和充型速度的增大可提高铸件的抗拉强度、屈服强度,但是铸造压力增大到一定程度后强度上升幅度减缓。

AC4CH alloy castings were produced by squeezing casting, and effects of casting pressure, filling velocity and filling distance on microstructure and properties of the castings were investigated. Microstructure of the squeezed AC4CH parts is composed of α-Al phase and eutectic Si phase, and the grain size in the microstructure is obviously refined with increasing in filling distance. With increasing in filling pressure and filling velocity, eutectic Si phase is decreased with more uniform distribution, and the tensile strength and yield strength of the parts are greatly improved, however, tensile strength is increased slowly wien the filling pressure exceeds a critical value.