摘要
在含有EDTA-Ca和Na2HPO4的电解液中,以恒电流方式制备富含Ca和P的镁合金微弧氧化陶瓷膜,研究电流密度对陶瓷膜结构及耐蚀性的影响。利用涂层测厚仪、X-射线荧光光谱仪(XRF)、X-射线衍射仪(XRD)、扫描电子显微镜(SEM)及电化学工作站对陶瓷膜厚度、元素组成、相组成、表面形貌及膜层在Hank溶液中的耐蚀性进行了测试。结果表明:随着电流密度的增加,膜层的厚度及Ca/P均呈现先增加后减小的趋势;膜层主要由MgO及MgAl2O4组成,膜层中的Ca,P以非晶形式存在;陶瓷膜均呈现典型的微弧氧化形貌,随着电流密度的增加,孔径逐渐增大,分布逐渐趋于不均匀,甚至出现裂痕;电流密度为100 mA/cm2,MgAl2O4含量最高,膜层的耐蚀性最佳。
The ceramic films containing Ca and P were prepared in an electrolyte containing EDTA？Ca and Na2HPO4 by micro？arc oxidation with constant current mode. The effects of current density on the microstructure and corrosion resistance of the oxide films were investigated. The thickness,element composition,phase composition,surface morphology and corrosion resistance of the oxide films in Hank＇s solution were analyzed by coating thickness gauge,X？ray fluorescence（XRF）,X？Ray diffraction （XRD）,scanning electron microscopy（SEM）and electrochemical workstation. The results show that with current density increasing,the thickness and Ca/P of the oxide films increase first and then decrease. The oxide films are mainly composed of MgO and MgAl2O4,and Ca and P inside the oxide layer exist with amorphous phase. As the current density increases,the films exhibit typically crater？like structure,and the pore diameter increases with uneven distribution until crack occurs. When the current density is 100 mA/cm^2,the content of MgAl2O4 in the oxide film reaches the highest,and corrosion resistance of the films is optimum.
出处
《兵器材料科学与工程》
CAS
CSCD
北大核心
2013年第4期33-37,共5页
Ordnance Material Science and Engineering
基金
吉林省教育厅"十二五"科学技术研究项目(2012-172)
吉林省科技发展计划项目(20100546)
四平市科技发展计划项目(2011016)
吉林师范大学研究生创新科研计划项目(201122)
关键词
镁合金
微弧氧化
电流密度
Ca和P
耐蚀性
magnesium alloys
micro-arc oxidation
current density
Ca and P
corrosion resistance
