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采用挤压铸造(液态模锻)工艺制备了A357铝合金螺旋线试件,使用化学成分分析和金相分析方法研究了流程长度对合金成分偏析及组织偏聚的影响.结果表明:在沿流程方向上,流程的开始端和流程末端的Si元素和Mg元素含量大于流程中段的含量.合金的初始α晶粒尺寸随着流程长度的增加先增大后变小.初生固相率随着流程长度的增大呈现波动变化.造成流程成分偏析和组织变化的原因是在挤压铸造凝固阶段中补缩液相的强迫运动.
A357 aluminum alloy spiral specimens were prepared by squeeze casting (liquid forging) process, and chemical composition analysis and metallographic analysis were used to study the effects of process length on segregation of alloy composition and segregation of the microstructure. The results show that, Direction, the content of Si element and Mg element at the beginning of the process and the end of the process is larger than that in the middle of the process.The initial α grain size of the alloy first increases and then decreases with the increase of the length of the process. The increase of length shows the variation of fluctuation, and the reason of component segregation and microstructure change in the process is the forced movement of the liquid phase in the squeeze casting solidification phase.