Ni元素对等离子喷涂铁基涂层组织和摩擦磨损性能的影响

Effect of Ni Element on Microstructure and Tribological Properties of Plasma Sprayed Iron-Based Coatings

为解决铝合金发动机缸体耐磨性差的问题,采用等离子喷涂技术在铝合金表面制备了不同Ni含量的铁基涂层(XPT-512-Ni),系统研究金属Ni对铁基涂层组织结构、力学性能以及摩擦磨损性能的影响。结果表明:XPT-512-Ni系铁基涂层组织主要由铁素体(F)、渗碳体(Fe3C)以及少量FeO和Ni相组成;涂层与铝基体形成良好的机械咬合,且涂层孔隙率随着金属Ni的加入而降低;铁基涂层的硬度随着Ni含量增加而降低;与XPT-512涂层相比,载荷30 N时XPT-512-30Ni涂层的油润滑磨损率降低了88.41%,10 N时XPT-512-10Ni涂层的干摩擦磨损率降低了81.32%,金属Ni的加入有效改善了等离子喷涂铁基涂层的服役性能,为发动机的轻量化发展提供了借鉴。

In order to solve the problem of poor wear resistance of aluminum alloy used for engine cylinder,the iron-based coatings(XPT-512-Ni)with different Ni content were prepared on the surface of aluminum alloy by plasma spraying.The effects of Ni element on the structure,mechanical properties,friction and wear properties of the coatings were investigated.The results show that the XPT-512-Ni iron-based coating is mainly composed of ferrite(F),cementite(Fe3C),as well as a small amount of FeO and Ni phases;a good mechanical bond is found between the coating and aluminum matrix;with an increase in the Ni content,the porosity of the coating decreases,and the hardness of the iron-based coating decreases;compared with XPT-512 coating,the wear rate of XPT-512-30 Ni coating with oil lubrication decreases by 88.41%under a load of 30 N and the wear rate of XPT-512-10 Ni coating by dry friction decreases by 81.32%under a load of 10 N.It is concluded that the Ni addition can effectively improve the service behavior of plasma-sprayed iron-based coating on the surface of aluminum cylinder,which provides a reference for the development of lightweight engine.