摘要
采用两阶段升压模式在ZK60镁合金基体上进行微弧氧化(MAO).通过微弧氧化过程中电流随时间的变化分析膜层生长过程,利用扫描电镜及其附带的能谱测试仪观察膜层微观结构并分析膜层成分及元素分布情况,用X射线衍射仪研究膜层物相组成.结果表明:该模式下制备的MAO膜层表面微孔呈现"火山口"喷射形状,并存在孔中套孔结构;微弧放电时提供反应向内的驱动力,使其发生内氧化,形成锯齿状膜基结合面;该模式下微弧氧化成型过程经历了陶瓷颗粒形成阶段,陶瓷颗粒聚集成表面岛阶段及表面岛烧结合并阶段;两阶段升压模式下获得的微弧氧化膜层由MgO方镁石和MgAl2O4尖晶石两种物相构成,且基体元素与电解液元素在微弧氧化反应中存在传质过程.
Micro-arc oxidation(MAO)process was conducted on ZK60 Mg alloy under two-step voltage-increasing mode by a DC pulse electrical source.The growth process of coatings was analyzed by voltage-time responses during the MAO process.The microstructural characteristics of coatings were investigated by means of scanning electron microscope(SEM)coupled with an energy dispersive spectrometer(EDS).The phase constituents of the coating were characterized by X-ray diffraction(XRD).The results indicated that the"pores in pores"structure can be observed on the surface of the coating.The pores presented spray configuration takes the shape of"Crater".The micro-arc discharge on the surface of the sample provided the driving force of reaction to occur inwardly,which led to the internal oxidation of the magnesium alloy and the formation serrated bonding cross section.The formation of MAO coating consists of ceramic particle formation,the island integration of ceramic particles and island sintering and amalgamation.There was a mass transfer process of matrix elements and electrolyte elements during MAO reaction and the resultant phases of coating were periclase MgO and spinel MgAl2O4.
作者
王泽鑫
周进驰
叶飞
芦笙
汤莉
WANG Zexin;ZHOU Jinchi;YE Fei;LU Shen;TANG Li(School of Materials Science and Engineering,Jiangsu University of Science and Technology,Zhenjiang 212003,China)
出处
《江苏科技大学学报（自然科学版）》
CAS
2019年第6期14-20,共7页
Journal of Jiangsu University of Science and Technology:Natural Science Edition
基金
江苏省研究生科研与实践创新计划资助项目(KYCX18-2317)
关键词
ZK60镁合金
微弧氧化
两阶段升压
生长机理
ZK60 Mg alloy
micro-arc oxidation
two steps voltage-increasing
mechanism
