在甘油润滑下TiAlN涂层的超低摩擦和磨损特性

Ultralow Friction and Wear Properties of TiAlN Coatings Lubricated by Glycerol

TiAlN涂层具有优异的力学性能,在刀具领域具有广泛的应用背景,然而优化制备参数以获得性能更为优异的TiAlN涂层仍需要做进一步的研究,同时与TiAlN涂层相适应的绿色润滑剂也是当前亟待解决的问题之一。基于磁控溅射技术,研究Al靶溅射电流对TiAlN涂层结构和力学性能的影响,考察甘油润滑下TiAlN涂层的摩擦学性能,并利用X射线光电子能谱探究甘油的润滑机理。结果表明:当溅射电流为3 A时得到的TiAlN-3A涂层具有最致密的晶状结构及最优的力学性能。在甘油润滑下,TiAlN-3A涂层的摩擦因数仅为0.007,其磨损率为2.62×10^(-6)mm^(3)N^(-1)m^(-1)。XPS分析表明,甘油在钢球与TiAlN涂层相对滑动过程中发生摩擦降解反应,在表面上生成新的产物FeOOH。FeOOH的亲水性使得在接触区域表面吸附甘油分子及甘油降解产物形成流体润滑层,可提供优异的减摩和耐磨性能。

TiAlN coating has found a wide application in the tool field as its excellent mechanical properties.However,more research is still needed to optimize the processing parameters to enhance mechanical properties of TiAlN coating.Moreover,it is urgent to develop green lubricants which are compatible with TiAlN coating.Based on magnetron sputtering technology,the effect of Al target sputtering current on the microstructure and mechanical properties of TiAlN coatings was studied,and the tribological properties of TiAlN coatings under glycerol lubrication conditions were evaluated.The action mechanism of glycerol on TiAlN coating was explored by using X-ray photoelectron spectroscopy.The results showed that TiAlN-3A coating obtained at 3 A has the densest crystalline structure and the best mechanical properties.The friction coefficient of TiAlN-3A coating was only 0.007,and its wear rate was 2.62×10^(-6)mm^(3)N^(-1)m^(-1) under lubrication of glycerol.XPS analysis indicated that the degradation reaction of glycerol occurred during the sliding of the steel ball against the TiAlN coating,and a new product FeOOH was formed on the surface.Due to the hydrophilicity of FeO OH,glycerol molecules and its degradation products were adsorbed on the surface of the contact area to form a fluid lubricant layer,providing excellent friction-reducing and wear resistant properties.