MoW喷涂层导电性及电弧烧蚀试验研究

Research on Conductivity and Arc Erosion Test of MoW Coating

摘要:

采用超音速等离子喷涂技术在45CrNiMoVA钢表面制备了MoW合金涂层,测试了涂层结合强度。利用电阻仪测试了涂层的导电性,用高压电弧装置对MoW涂层进行了大气环境不同放电电流的电弧烧蚀试验。通过场发射扫描显微镜(SEM)、电子能谱仪(EDS)分析了涂层组织,使用X射线衍射仪测试了涂层相组成。结果表明：MoW涂层与基体结合良好,导电率为6.12%IACS。W使涂层导电率有所降低；孔隙率是涂层导电性能较低的主要原因之一。随着放电电流增大,MoW涂层电弧烧蚀面积增大明显,呈现出两种烧蚀形貌；孔隙率越大、表面粗糙度越小,涂层耐电弧烧蚀性能越差。MoW喷涂层抗电弧烧蚀性能优于纯Mo喷涂层。

Abstract:

MoW coating was prepared by supersonic plasma spraying technology on 45CrNiMoVA steel. The bonding strength of the coating were tested. The electrical conductivity of the coating was tested by resistance tester. The arc erosion test of MoW coating with different discharge current in atmosphere was carried out by using high voltage arc device. The coating structure was analyzed by field emission scanning microscope (SEM) and electron spectrometer (EDS), and the phase composition of the coating was tested by X ray diffractometer. The results show that the MoW coating prepared by the supersonic plasma spraying process has good adhesion with the substrate, and the conductivity is 6.12%IACS. The addition of W improves the chemical defect ratio of coating and leads to the decrease of conductivity. Porosity is one of the main reasons for low conductivity of coating. The oxidation has little influence on the conductivity of MoW coating. As the discharge current increases, the MoW coating arc erosion area increased significantly; the current size of the errosion coating reflects two different errosion morphology; the greater the porosity, surface roughness, arc erosion resistance of the coating performance worse. The arc erosion resistance of MoW coating is better than that of pure Mo coating.