磁场辅助激光熔覆制备Ni60CuMoW复合涂层

采用磁场辅助激光熔覆技术,在Q235钢表面制备了Ni60CuMoW复合涂层,借助SEM，EDS 和XRD 等表征手段对涂层进行了微观组织和物相分析，利用维氏硬度计测试了复合涂层截面的显微硬度分布，通过摩擦磨损实验和电化学测试系统研究了复合涂层的磨损性能和耐腐蚀性能。研究结果表明:涂层主要由-Ni,Cu）固溶体、硅化物和硼化物组成，Cr3Si晶粒细化且均匀致密；磁场辅助作用下，激光熔覆涂层平均显微硬度达到913HV0.5，为无磁场辅助涂层的1.5 倍，磨损失重仅为无磁场涂层的36%，自腐蚀电位上升了100 mV，腐蚀电流密度降低了70%，耐磨耐蚀性能得到了显著改善。

Microstructure and property of Ni60CuMoW composite coating treated prepared with magnetic field and laser cladding process

In order to obtain fine grain structure and improve laser cladding coating quality, Ni60CuMoW composite coating was fabricated by magnetic field assisted laser cladding technique on Q235 steel surface. The microstructure and phase composition of the cladding composite coating were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectrometer (EDS). The cross-section hardness and abrasion performance of the cladding composite coating were measured by Vickers hardness tester and friction and wear device. The corrosion behaviors of the composite coatings were characterized through electrochemical test system. The results show that the phase of the laser cladding composite coatings is mainly composed of γ-(Ni, Cu)solid solution, silicides and borides. The Cr3Si grain is fine, uniform and compact. The average hardness of the composite coating is 913HV0.5, which is 1.5 times higher than that of the coating without magnetic field. The weight loss of laser cladding composite coating is only about 36% the coating without magnetic field. The corrosion potential increases about 100 mV, and corrosion current density decreases by 70%. The wear behaviors and corrosion resistance of the laser cladding composite coatings are significantly improved.