激光熔覆WC增强Ni基复合涂层的研究进展

激光熔覆是一种新型表面改性技术,具有能量密度高、稀释率可控、涂层与基体呈现良好的冶金结合等优点,且快热快冷的特性有利于在基材表面形成具有细小致密组织的涂层,从而获得耐磨耐蚀等优异性能.WC增强Ni基复合涂层因兼具陶瓷材料优异的耐高温、耐磨性和金属材料良好的强韧性,近些年成为激光熔覆研究领域的热点.综述了激光熔覆WC增强...

Research Progress of Laser-cladding WC Reinforced Ni-based Composite Coating

Laser cladding is a new type of surface modification technology, which has the advantages of high energy density, controllable dilution rate, good metallurgical bonding between the coating and the substrate. The characteristics of fast heating and fast cooling are conducive to the formation of a coating with fine and compact structure on the surface of the substrate, so as to obtain excellent performance such as wear resistance and corrosion resistance. In recent years, WC reinforced Ni-based composite coatings have become a hot topic in the field of laser cladding because it can combine the excellent high temperature resistance and wear resistance of ceramics with the good strength and toughness of metals. In this paper, the research progress of laser cladding WC reinforced Ni-based composite coatings is reviewed. The role of WC in composite coatings, including the strengthening mechanism of WC and its effect on the friction and wear properties and wear mechanism of the composite coatings were summarized. On this basis, the material system of laser cladding WC reinforced Ni-based composite coatings was discussed from the aspects of Ni-based alloys, the addition amount, size, type of WC reinforcing phase and the influence of rare earth elements. The distribution and existence form of WC in the composite coating were emphatically discussed. At the same time, the effects of laser power, scanning speed, substrate pretreatment and new laser cladding technologies, such as ultrasonic vibration assist and induction heating, on the forming quality, microstructure, phase composition and properties of the composite coatings were reviewed. Finally, the existing problems and future development of laser cladding WC reinforced Ni based composite coatings were prospected.