摘要
为提高镁合金表面的耐腐蚀性能,采用微弧氧化技术在AZ31B镁合金上制备了稀土Y_(2)O_(3)/MgO复合陶瓷膜层,提高了基体的硬度和耐腐蚀性能。稀土纳米Y_(2)O_(3)的加入提高了电解液的电导率,相同处理时间处理电压逐渐升高。扫描电镜(SEM)结果表明微孔数量随Y_(2)O_(3)浓度增加逐渐减少,微孔直径逐渐减小,孔隙率逐渐降低。X射线衍射(XRD)检测结果表明,膜层主要由MgO和Y_(2)O_(3)组成。膜层中Y_(2)O_(3)含量随着电解液中Y_(2)O_(3)浓度的增加逐渐增加。随着Y_(2)O_(3)含量从0 g/L增加到4 g/L,膜层的表面粗糙度从1.85μm下降到1.48μm,膜层厚度从52.33μm增加到58.37μm。在Y_(2)O_(3)浓度为3 g/L时,表面硬度提高到365.6 HV,腐蚀电流降低到2.872×10A。
Aiming at improving the corrosion resistance of magnesium alloy surface,rare earth Y_(2)O_(3)/MgO ceramic coatings were prepared on AZ31 B magnesium alloy via micro-arc oxidation.The hardness and corrosion resistance of the substrate increased.The addition of nano Y_(2)O_(3)raised the conductivity of the electrolyte,and the voltage at the same treatment time increased.The scanning electron microscopy(SEM)results showed that,the number of“crater”holes,the diameter of micro pores and the porosity decreased with the increase of Y_(2)O_(3)concentration.X-ray diffraction results indicated that the coatings were mainly consisted of MgO and Y_(2)O_(3),and the Y_(2)O_(3)content in the coatings increased with the increase of Y_(2)O_(3)concentration in electrolyte.Moreover,as the Y_(2)O_(3)concentration increased from 0 g/L to 4 g/L,the surface roughness of the coating declined from 1.85μm to 1.48μm,and the thickness was improved from 52.33μm to 58.37μm.When the Y_(2)O_(3)concentration was 3 g/L,the surface hardness of the as-obtained coating increased to 365.6 HV,and the corrosion current decreased to 2.872×10A.
作者
李鑫
张晟豪
王子恒
郭豫鹏
陆晓峰
LI Xin;ZHANG Sheng-hao;WANG Zi-heng;GUO Yu-peng;LU Xiao-feng(School of Mechanical and Power Engineering,Nanjing Tech University,Nanjing 211816,China)
出处
《材料保护》
CAS
CSCD
2022年第10期37-42,共6页
Materials Protection
基金
大学生创新创业项目(202010291206Y)
南京工业大学引进人才科研启动费项目(3827400212)资助。
关键词
微弧氧化
AZ31B镁合金
稀土氧化钇
复合膜层
耐腐蚀性能
micro-arc oxidation
AZ31B magnesium alloy
rare earth yttrium oxide
composite coating
corrosion resistance
