摘要
研究了不同 Zr 含量对 Mg-9Gd-4Y 合金晶粒大小的影响及 Zr 的晶粒细化机制．结果表明,Zr 可以明显细化合金的晶粒,且随 Zr 含量增加,晶粒变得更细小．微观组织分析表明,在 Zr 含量较高的合金中,几乎每个晶粒内都含有至少一个富 Zr 的核；而在 Zr 含量较低的合金中没有发现这种核．在高 Zr 含量和低 Zr 含量的合金中,晶粒细化的机制不同：在低 Zr 含量合金中,Zr 以抑制品粒长大为主；在高 Zr 含量合金中,Zr 以促进异质形核为主．
The effect of Zr content on the grain size of Mg-gGd-4Y alloys and the grain refinement mechanism of Zr were investigated. The results reveal that Zr can refine grains of the alloys greatly, and the grains become finer with the increase of Zr content. The microstructure analysis shows that there are at least one Zr-rich core in the almost each grain in the alloys with high Zr content, whereas the characteristic Zr-rich cores are not found in the alloy with low Zr content. It is suggested that the grain refinement mechanism of zirconium in the low Zr alloys be different from that in the high Zr alloys： the zirconium works mainly by restricting grain growth in the low Zr alloys, and by generating nucleants in the high Zr alloys.
出处
《北京科技大学学报》
EI
CAS
CSCD
北大核心
2006年第2期148-152,共5页
Journal of University of Science and Technology Beijing
基金
国防预研基金项目(No.51412020304QT7106)
国家"863"计划项目(No.03AA741043)
湖南省自然科学基金项目(No.03JJY4051)
