稀土Gd对SLM成型医用Mg-Zn-Gd合金耐蚀性能的影响  

Effect of Gd Element on Corrosion Rate of SLM Formed Medical Magnesium Alloy

作　　者：杨光[1] 王琮玮 王琮瑜 王金业[1] 刘大志 Yang Guang;Wang Congwei;Wang Congyu;Wang Jinye;Liu Dazhi(Hebei University of Science&Technology,Shijiazhuang 050018,China;Tangshan Weihao Magnesium Powder Co.,Ltd,Tangshan 064406,China)

机构地区：[1]河北科技大学,河北石家庄050018 [2]唐山威豪镁粉有限公司,河北唐山064406

出　　处：《稀有金属材料与工程》2022年第6期2167-2174,共8页Rare Metal Materials and Engineering

基　　金：国防基础科研计划(JCKY2018407C004);中央引导地方科技发展资金(206Z1806G);河北省高校百名优秀创新人才支持计划(SLRC2019050);河北省研究生创新资助项目(XJCXZZSS202117)。

摘　　要：镁合金具有高比强度与良好的生物相容性,是一种理想的骨植入材料。因镁合金降解速率过快在临床应用中受到限制,通过选区激光熔化(SLM)可对其实现合金化并改善耐蚀性能。利用SLM成型Mg-1Zn-xGd(x=0,0.25,0.5,1,2,质量分数,%)合金,测试镁合金在模拟体液中浸泡72 h平均腐蚀速率的变化趋势,采用SEM、EDS与TEM检测手段辅助分析腐蚀机制。结果表明,Gd含量对镁合金腐蚀速率影响显著,添加0%~2%Gd后镁合金降解速率呈先降低后升高趋势,在添加0.5%Gd时镁合金具有最佳耐腐蚀性能。腐蚀反应产生的表面钝化膜能够在一定程度减缓腐蚀的进行,添加过量Gd后沿晶界析出Mg_(5)Gd相增多,加剧了镁合金的腐蚀。Magnesium alloy is an ideal bone implant material with high specific strength and good biocompatibility.Due to the limitation of rapid degradation rate of magnesium alloy in clinical application,it can be alloyed and corrosion resistance can be improved by selective laser melting(SLM).Mg-1Zn-x Gd(x=0,0.25,0.5,1,2,wt%)alloy was formed by SLM,and the average corrosion rate of magnesium alloy soaked in simulated body fluid for 72 h was tested.The corrosion mechanism was analyzed by SEM,EDS and TEM.The results show that Gd content has a significant effect on the corrosion rate of magnesium alloy,and the degradation rate of magnesium alloy decreases first and then increases with the addition of 0wt%~2wt%Gd,and the magnesium alloy has the best corrosion resistance with the addition of 0.5wt%Gd.The surface passivation film produced by the corrosion reaction can slow down the corrosion process to a certain extent,and the Mg_(5)Gd phase precipitated along the grain boundary increases after the addition of excessive Gd,resulting in intensified corrosion of magnesium alloy.

关 键 词：稀土镁合金 耐蚀性能 降解速率 显微组织 

分 类 号：TG146.22[一般工业技术—材料科学与工程]