Department of Chemistry and School of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin 150001, P.R. China.
ACS Appl Mater Interfaces. 2010 Mar;2(3):808-12. doi: 10.1021/am900802x.
Current density is a key factor of plasma electrolytic oxidation process. Its influences on structure, mechanical, and tribological characteristics of ceramic coatings on ZK60 Mg alloy by pulsed bipolar microplasma oxidation in Na(3)PO(4) solution were studied in this paper. Thickness, structure, composition, mechanical property, and tribological characteristics of the coatings were studied by eddy current coating thickness gauge, scanning electron microscope (SEM), X-ray diffraction (XRD), nanoindentation measurements, and ball-on-disk friction testing. The results show that all the coatings prepared under different current densities are composed of MgO phase. The amount of MgO phase, thickness and friction coefficient of the coatings increased with the increasing current density. Among three ceramic coatings produced under three current densities, the coating produced under the current density of 7 A/dm(2) got the highest nanohardness and lowest wear rate with the value of 1.7 GPa and 1.27 x 10(-5) mm(3)/Nm.
电流密度是等离子体电解氧化过程的一个关键因素。本文研究了在 Na(3)PO(4)溶液中，通过脉冲双极性微等离子体氧化在 ZK60 Mg 合金上制备陶瓷涂层时电流密度对其结构、力学和摩擦学特性的影响。采用涡流测厚仪、扫描电子显微镜（SEM）、X 射线衍射（XRD）、纳米压痕测量和球盘摩擦试验研究了涂层的厚度、结构、组成、力学性能和摩擦学特性。结果表明，在不同电流密度下制备的所有涂层均由 MgO 相组成。随着电流密度的增加，MgO 相的含量、涂层的厚度和摩擦系数均增加。在三种电流密度下制备的三种陶瓷涂层中，电流密度为 7 A/dm(2)时制备的涂层具有最高的纳米硬度和最低的磨损率，其值分别为 1.7 GPa 和 1.27 x 10(-5) mm(3)/Nm。
