挤压Mg-Zn-Y合金的腐蚀行为  

Corrosion Behavior of Extruded Mg-Zn-Y Alloys

作　　者：刘光文[1] 张英波[1] 李彬[1] 姚丹丹[1] 

机构地区：[1]西南交通大学材料科学与工程学院,成都610031

出　　处：《材料导报》2015年第22期101-104,共4页Materials Reports

基　　金：国家自然科学基金(51201142);四川省科技计划项目(2014JY0020)

摘　　要：研究了大挤压比(81∶1)条件下Mg-Zn-Y合金在3.5%(质量分数)NaCl水溶液中的腐蚀行为。通过失重法和电化学法测试了合金的腐蚀性能,并对合金的微观腐蚀过程进行了分析。结果表明:随着Zn、Y含量的增加,准晶相含量逐渐增加,合金的耐蚀性能逐渐降低。准晶相和α-Mg基体界面处的α-Mg基体一侧优先发生腐蚀,随后一方面向基体扩宽延伸而形成腐蚀坑;另一方面逐渐沿I-phase与α-Mg基体界面扩展,直至界面结合处形成裂纹环路而导致I-phase颗粒脱落,进而在合金表面形成点蚀坑。The corrosion behavior of extruded Mg-Zn-Y alloys at the large extrusion ratio of 81 ： 1 in 3. 5% NaCl solution were investigated. The corrosion properties of Mg-Zn-Y alloys were studied by immersion tests and electrochemical measurements. The results show that the volume fraction of I-phase increased with the increasing of Zn and Y contents, but the corrosion resistance of the alloys decreased. The α-Mg matrix surrounding the I-phase to be corroded preferentially, then on the one hand, corrosion extended toward the Mg matrix and formed corrosion pits. On the other hand, corrosion extended along the interface of I-phase and α-Mg matrix, until the formation of crack loop at the interface which caused the I-phase particles fall off from the substrate surface and formed corrosion pits.

关 键 词：MG-ZN-Y合金 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]