超声辅助微弧氧化的含石墨复合膜的组织结构及摩擦学性能

Microstructure as well as Friction and Wear Behavior of Graphite-Containing Composite Coating Prepared on Aluminum Substrate by Ultrasound-Assisted Micro-Arc Oxidation

为了提高铝合金微弧氧化膜的摩擦磨损性能,在微弧氧化电解液中添加石墨颗粒,并引入超声波进行微弧氧化,制备了含石墨的复合膜。利用扫描电子显微镜(SEM)观察了膜的表面和截面形貌,用X射线衍射仪(XRD)和激光拉曼光谱仪分析了膜的组成,在摩擦试验机上评价了膜的摩擦学性能。结果表明:添加石墨能有效降低微弧氧化膜的摩擦系数;同时引入超声波更有利于石墨微粒的分散,促进其进一步扩散和渗透,从而得到石墨分布更均匀、更致密的复合膜,膜的摩擦系数和磨损程度进一步降低。

Graphite powder was introduced into micro-arc oxidation electrolyte to prepare graphite- containing composite coating on Al alloy substrate via ultrasound-assisted micro-arc oxidation.The surface and cross- section morphologies of as- prepared graphite-containing composite coating were observed with a scanning electron microscope,while its composition was determined by X- ray diffraction and laser Raman spectrometry.Moreover,a friction and wear tester was performed to evaluate the friction and wear behavior of the as- prepared graphite- containing composite coating.Results showed that introducing graphite helped to effectively reduce the friction coefficient of the micro-arc oxidation coating,while applying ultrasound was favorable for enhancing the dispersion and permeation of graphite powder in the micro- arc oxidation coating thereby affording composite coating with improved uniformity and compactness as well as reduced friction coefficient and wear rate.