稀土对Al-Zn-M g-Cu/Al2O3陶瓷界面润湿性的影响

采用真空座滴法和熔铸法研究了在Al-Zn-Mg-Cu 合金中加入稀土(Ce、Y) 对Al2Zn2M g2Cu/Al₂O₃陶瓷界面润湿性的影响。结果表明,Al-Zn-Mg-Cu 合金中加入稀土可有效降低铝合金/Al₂O₃界面的接触角, 改善界面结合状态; 稀土改善界面润湿性存在一最佳含量范围, 添加Ce 的最佳含量约为0. 5w t% , Y 约为0. 7w t%。稀土改善润湿性的作用主要是稀土与Al₂O₃膜、Al₂O₃陶瓷发生反应。Mg、Zn、Cu 等合金元素在界面富集并参与界面反应对润湿性有利; 稀土与Mg、Zn、Cu 等合金元素适当组合改善润湿性的效果比单一稀土明显。 

EFFECT OF RARE EARTH ADDITIONS ON THE WETTABILITY OF AN-Al-Zn-Mg-Cu/Al2O3 SYSTEM

The Effect of rare earth additions (Ce or Y) on the wettability of an Al-Zn-Mg-Cu/Al2O3 system is investigated by vaccum sessile drop method and casting processing in this paper. The results show that rare earth additions into Al-Zn-Mg-Cu alloy can decrease the contact angles effectively and improve interfacial structure with optimum rare earth content being about 0.5wt% for Ce and 0.7wt% for Y. The behaviour of Ce and Y is considered to be the results of interaction between rare earths and the oxide film of the Al alloys or/and α Al2O3 plaque. The rare earth compounds, Ce 2O 3, Al 11 Ce 3, etc, in the interface of Al alloys/Al2O3, have been identified. The suitable combination of rare earths and alloying elements (Mg, Zn, Cu) improves wettability muchmore remarkably than a single rare earth element.