La对Al_2O_(3f)/Al-Mg复合材料凝固溶质偏析的影响

Effects of RE La on Solute Segregation of Al_2O_(3f)/Al-Mg Composites during Solidification

利用挤压铸造法制备了Al2O3f/Al-Mg-La复合材料。研究了La在铝合金基体中的分布,并探讨了La对基体凝固时溶质元素偏析的影响。结果表明,La富集在界面附近,有利于改善铝合金液对Al2O3f的润湿性,但是在界面上未发现任何富稀土相的形成。La的加入对基体合金中的Mg的偏聚没有很明显的影响,Mg和La作为表面活性元素都在界面处富集,且它们的分布位置大致一样。

The distribution of La in aluminum alloy matrix and its effects on solute segregation during matrix solidification are investigated based on Al_2O_ 3f /Al-Mg-La composites prepared by squeezing casting. The results show that enrichment of La on interface is favorable for improving the wettability of Al_2O_ 3f particle in liquid aluminum alloy. However, the absence of RE-enriched on interface are observed. La has slightly affected on segregation of Mg in matrix alloy, and both Mg and La can enrich on interface with the same position distribution.