挤压态低合金化Mg-0.5Bi-0.5Y-0.2Zn合金的腐蚀行为及力学性能  

Corrosion behavior and mechanical properties of extruded low-alloyed Mg−0.5Bi−0.5Y−0.2Zn alloy

作　　者：李峰 程伟丽[1,2] 余晖[3] 王红霞[1,2] 牛晓峰[1,2] 王利飞 李航[1] 侯华 Feng LI;Wei-li CHENG;Hui YU;Hong-xia WANG;Xiao-feng NIU;Li-fei WANG;Hang LI;Hua HOU(School of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Key Laboratory of Interface Science and Engineering in Advanced Materials,Ministry of Education,Taiyuan University of Technology,Taiyuan 030024,China;School of Materials Science and Engineering,Hebei University of Technology,Tianjin 300132,China;School of Materials Science and Engineering,North University of China,Taiyuan 030051,China)

机构地区：[1]太原理工大学材料科学与工程学院,太原030024 [2]太原理工大学新材料界面科学与工程教育部重点实验室,太原030024 [3]河北工业大学材料科学与工程学院,天津300132 [4]中北大学材料科学与工程学院,太原030051

出　　处：《Transactions of Nonferrous Metals Society of China》2023年第3期743-754,共12页中国有色金属学报（英文版）

基　　金：the financial supports from the National Natural Science Foundation of China (Nos. 51704209, 51701060, 51901153);the Natural Science Foundation of Shanxi Province, China (Nos. 201801D121088, 201901D211096);the Science and Technology Major Project of Shanxi Province, China (Nos. 20191102007, 20191102008)。

摘　　要：研发一种新型低合金化Mg-Bi-Y-Zn合金系,该合金系在673 K的挤压温度下成功成型。通过扫描电子显微镜(SEM)、电子背散射衍射(EBSD)、电化学试验和拉伸试验研究挤压态合金的腐蚀行为和拉伸性能。挤压后,合金表现出几乎完全的动态再结晶组织和典型的挤压织构,在晶粒内可以观察到一些亚微米级析出相。在SBF溶液中,合金的腐蚀模式由最初的点蚀为主转变为中间过程的丝状腐蚀为主;最后经长时间浸泡后,腐蚀模式转变为丝状腐蚀和局部晶粒脱落。挤压态Mg-0.5Bi-0.5Y-0.2Zn合金的屈服强度为237 MPa,极限抗拉强度为304 MPa,伸长率为31%,平均腐蚀速率为0.14 mm/a。由此可见,该合金表现出良好的拉伸性能和耐腐蚀性能匹配度,这主要归因于其均匀的晶粒结构和亚微米级析出相。因此本文所研发的Mg-0.5Bi-0.5Y-0.2Zn合金具有在生物医药领域的广阔应用前景。A novel low-alloyed Mg−Bi−Y−Zn alloy system was developed and extruded successfully at 673 K.The corrosion behavior and tensile properties of the extruded alloy were investigated through scanning electron microscopy(SEM),electron backscatter diffraction(EBSD),electrochemical tests and tensile test.The extruded alloy exhibits a nearly fully recrystallized grain structure with a scattered extrusion fiber texture and some sub-micron precipitates.In SBF solution,the dominated corrosion mode changed from galvanic induced pitting corrosion at initial stage to filiform-like corrosion and finally mixed pitting corrosion and local fall-off of grains during long-term corrosion processes.The tensile properties and corrosion resistance of the extruded Mg−0.5Bi−0.5Y−0.2Zn(wt.%)alloy are:tensile yield strength of 237 MPa,ultimate tensile strength of 304 MPa,elongation to failure of 31%and mean corrosion rate of 0.14 mm/a.The great balance between tensile properties and corrosion resistance is mainly attributed to the homogeneous grain structure and the presence of sub-micron scaled precipitates,indicating a promising potential in the application in biomedical field.

关 键 词：Mg-Bi基合金 挤压 腐蚀行为 力学性能 

分 类 号：TG178[金属学及工艺—金属表面处理] TG146.22[金属学及工艺—金属学]