采用半导体激光器在45#钢基体上制备金刚石复合涂层, 熔覆层材料为铁基粉末2Cr13和人造金刚石微粉的混合粉末, 熔覆设备使用2 kW光纤耦合半导体激光器。利用扫描电子显微镜(SEM)、能谱仪(EDS)、X射线衍射仪(XRD)对涂层的显微组织、元素分布和相结构进行分析; 并采用摩擦磨损试验机对涂层的摩擦磨损性能进行了测试。结果表明: 该复合涂层中的金刚石在激光的作用下发生了形态转变, 一部分完全碳化形成石墨; 另一部分不完全碳化形成石墨并残留小部分金刚石相。XRD分析涂层的相组成可知, 该涂层主要由硬质相Fe0.64Ni0.36、金刚石、FexCy、过饱和固溶体Cr和石墨等组成。由于涂层中金刚石及石墨的存在, 使得涂层具有优异的耐磨性能, 涂层的耐磨性相比未添加金刚石涂层提高了近60%, 涂层的磨损机制以磨粒磨损为主。

A 2 kW fiber-coupled diode laser was adopted to clad 2Cr13 iron-based powder mixed with artificial diamond powder on 45 steel to obtain diamond composite coating in this paper. The microstructure, element distribution and phase composition were investigated by scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS)and X-ray diffraction(XRD). Meanwhile, the wear resistances of layers with and without diamonds weres investigated by friction and wear testing machine under room temperature. The results show that diamonds in composite coating are changed by laser rapid heating—part of them transform to graphite completely and others remains. The XRD analysis shows that the coating is mainly composed of hard phases Fe0.64Ni0.36, diamond, FexCy and supersaturated solid solution Cr and graphite. Compared with the coating without diamonds, the abrasion resistance of coating with diamonds increases by nearly 60% because of hard diamonds and soft graphite. Abrasive wear is the predominant wearing mechanism of the coating.