铸造镁合金Mg-Zn-Y-Zr-Ca在模拟体液中的腐蚀行为  

Corrosion Behavior of As-cast Mg-Zn-Y-Zr-Ca Alloy in Simulated Body Fluid

作　　者：孙毅[1,2] 张文鑫 许春香[1,2] 张金山 韩少兵[1,2] 贾长健 SUN Yi;ZHANG Wenxin;XU Chunxiang;ZHANG Jinshan;HAN Shaobing;JIA Changjian(School of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024;Shanxi Key Laboratory of Advanced Magnesium-based Materials,Taiyuan 030024)

机构地区：[1]太原理工大学材料科学与工程学院,太原030024 [2]先进镁基材料山西省重点实验室,太原030024

出　　处：《材料导报》2017年第24期105-108,共4页Materials Reports

基　　金：国家自然科学基金(51574175;51474153)

摘　　要：采用光学显微镜和扫描电子显微镜研究了铸态Mg-3Zn-0.6Y-0.5Zr-0.3Ca(质量分数/%)合金的显微组织,采用失重法测试了合金在模拟体液中浸泡不同时间的生物腐蚀性能,并对合金的腐蚀行为进行分析。结果表明,Mg-3Zn-0.6Y-0.5Zr-0.3Ca合金中沿晶界连续分布的Mg3YZn6相对合金的腐蚀具有作为微阴极加速基体腐蚀或抑制腐蚀扩展的双重作用。Mg-3Zn-0.6Y-0.5Zr-0.3Ca合金的腐蚀过程分为3个阶段:晶界附近溶质原子贫化区形成几微米宽的腐蚀凹槽,在富Zr-贫Zr区形成大量腐蚀斑点,腐蚀凹槽和腐蚀斑点相互扩展破坏基体。The microstructure of the as-cast Mg-3Zn-0.6Y-0.5Zr-0.3Ca alloy was observed by optical and scanning electron microscopy.The biocorrosion properties of the alloy in simulated body fluid(SBF)were evaluated using mass loss experiments with different immersion time.The results based on the microstructure and the corrosion morphology observation and analysis show that the quasi-continuous network of I-phase(Mg 3YZn 6)at grain boundaries has a dual effect on the corrosion behavior of the alloy.As a cathode to accelerate corrosion or a barrier can restrain the further expansion of corrosion.The corrosion process can be divided into three stages,corresponding to corrosion features with different times.At the initial stage,the solute depleted zones formed corrosion grooves about several microns in width;at the middle stage,the regions with high concentration of Zr formed many corrosion pits in theα-Mg matrix;at the final stage,the corrosion grooves and corrosion pits extended toward theα-Mg matrix.

关 键 词：生物镁合金 模拟体液 准晶相 腐蚀行为 

分 类 号：TG146.22[一般工业技术—材料科学与工程]