La、Y微合金化对铝硅合金组织及其耐腐蚀性的影响

Effect of Microalloying with La and Y on Microstructure and Corrosion Resistance of Al-Si Alloy

研究了La、Y微合金化对A356铝合金组织及其耐腐蚀性的影响。结果表明,在微合金化的作用下,A356铝合金随La、Y元素加入量的增加,其初生相细化较显著并呈先增大后减小的趋势,添加0.15wt%La,0.3wt%Y时,晶粒细化效果最佳。此微合金化对A356合金中α-Al晶粒的细化效果明显优于La。在微合金化的作用下,A356铝合金的耐腐蚀性得到了显著的改善,这主要是通过微合金化手段细化其晶粒来实现的。

The effect of microalloying with La and Y on the microstructure and corrosion property of Al-Si alloy was investigated. It is found that La, Y elements can refine grain of primary phase markedly. The grain’s size firstly increases and then decreases with the additions of La, Y elements. When the La, Y additions are 0.15wt% and 0.3 wt%, respectively, the effect of grain refinement is optimum. The effect of grain refinement of combining microalloying with La and Y is much better than that with La element. The role of microalloying enhances the corrosion resistance of the A356 obviously. The improvement of corrosion resistance of A356 mainly attributes to the role of refining grain by microalloying.