稀土在镁合金中作用的研究现状

Development on Effects of Rare Earth Element in Magnesium Alloys

稀土元素在镁合金中具有阻燃、净化熔体等作用,能有效改善合金的铸造性能;可细化显微组织、形成准晶相、抑制形变织构,提高镁合金的室温及高温强度和塑韧性等力学性能;并改变镁合金表面腐蚀层结构、控制阴极相数量和分布以及影响电化学过程,从而改善镁合金的耐腐蚀性能。总结了利用稀土元素改善镁合金组织性能的研究现状,并对稀土镁合金的发展前景进行了展望。

With the addition of rare earth elements （RE）, the ignition temperature and purity of magnesium alloy were increased. Thus the qualities of magnesium alloy ingots and casts were improved. Also, the mechanical properties at room and elevated temperatures of RE-containing magnesium alloys were improved, due to the refinement of microstructure, the formation of some quasi-crystal phases and the decrease of deformation texture. The structure of the corrosion products, the electrochemical process, and the number and distribution of secondary phases were changed as RE was added into magnesium alloys. Therefore, the corrosion resistance was enhanced. The recent progress in the application of RE in magnesium alloys to improve the microstructure and properties was reviewed. Some prosgects of tke magnesium alloys containing rare earth were proposed.