A356铝合金的铸造方法对其组织和性能的影响

Influence of Casting Methods on Microstructure and Performance of A356 Alloy

通过电磁搅拌＋连续铸造、人工搅拌＋连续铸造和常规铸造3种方式制备了A356合金，重点研究了铸造方式对合金组织和性能的影响。研究结果表明，与常规铸造相比，电磁或人工搅拌＋水冷热顶铸造工艺制备的材料晶粒得到了较大的细化，针孔度和Si偏析都有显著的改善，针孔度由常规铸造的2～3级提高到1级，而Si偏析由常规铸造的0．10％～0．54％降低到0．08％～0．16％。电磁搅拌或人工搅拌＋连续铸造得到材料的硬度和冲击韧性较常规铸造也都有一定的提高，分别提高了0．2倍和3倍以上。

With electromagnetic stirring ＋ Hot pot billet casting technology, manpower stirring ＋ Hot pot billet casting technology and common casting technology, A356 Alloy were prepared successfully and the influence of casting methods on microstructure and performance of A356 alloy was focused on. The results show that, compared with common casting technology, the crystal grain, pinhole degree and Si segregation of alloy made by electromagnetic stirring ＋ Hot pot billet casting technology were all improved obviously. The pinhole degree was increased to single stage from 2 -3 stage and Si segregation was decreased to 0.08%--0. 16% from 0. 10%-0. 54% of the common casting technology. Compared with common casting technology, hardness and impact ductility of alloy made by electromagnetic stirring ＋ Hot pot billet casting technology and manpower stirring ＋ Hot pot billet casting technology was increased 0.2 and 3 times respectively.