水热条件下Mg-3Nd-Zn-Zr合金化学转化膜的研究  

Performance of Chemical Conversion Film on Mg-3Nd-Zn-Zr Alloy Prepared by Hydrothermal Treatment

作　　者：张满意[1,2] 郭兴伍[1,2] 杨海燕[1,2] 王渠东[1,2] 丁文江[1,2] 

机构地区：[1]上海交通大学轻合金精密成型国家工程研究中心,上海200240 [2]上海交通大学金属基复合材料国家重点实验室,上海200240

出　　处：《腐蚀科学与防护技术》2011年第3期233-238,共6页Corrosion Science and Protection Technology

基　　金：国家自然科学基金项目(50674067);国家高技术研究发展计划项目(2009AA033501)资助

摘　　要：采用水热法在Mg-3Nd-Zn-Zr合金表面制备无铬化学转化膜,研究了乙酸钠对膜层的影响.用场发射扫描电镜、X射线衍射、电化学测试方法分别研究了转化膜的形貌、相组成和耐蚀性能.结果表明,转化膜主要由球形颗粒状和层片状的Mg(OH)_2相、以及少量含Si的非晶化合物组成;适量的乙酸钠能促进球形颗粒状和层片状Mg(OH)_2发生团聚,缩小层片间隙,且对转化膜的生长速率影响小;膜层厚度可以达到约25μm,与基体结合牢固,耐蚀性得到明显提高.A chrome-free chemical conversion film for Mg-3Nd-Zn-Zr alloy by hydrothermal process was studied.The effect of CH_3COONa on the properties of the films was then examined. The surface morphology,microstructure and corrosion resistance of the films were characterized by FE-SEM,XRD and electrochemical testing method.The results show that the conversion films mainly consist of granular particles and flakes of Mg（OH）_2 phase.A few of amorphous compounds containing Si also are found in the films.Moderate CH_3COONa can promote agglomerating of granular particles and flakes of Mg（OH）_2 without affecting the growth rate of films,which shrinks the gap of flakes Mg（OH）_2,so the porosity of the conversion films is decreased.The thickness of the film which has great adhesion with the substrate can reach about 25μm,and the corrosion resistance is improved significantly.

关 键 词：水热条件 Mg-3Nd-Zn-Zr合金 化学转化 乙酸钠 

分 类 号：TG174.45[金属学及工艺—金属表面处理]