Mo-W喷涂层导电性及电弧烧蚀试验

Conductivity and Arc Erosion Test of Mo-W Coating

采用超音速等离子喷涂技术在45CrNiMoVA钢表面制备了Mo-W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Mo-W涂层进行了大气环境不同放电电流的电弧烧蚀试验。通过场发射扫描电镜(SEM)、能谱(EDS)仪分析了涂层组织,使用X射线衍射(XRD)仪测试了涂层相组成。结果表明:Mo-W涂层与基体结合良好,但导电率较低,只有6.12%IACS。孔隙率是涂层导电性能较低的主要原因。随着放电电流增大,Mo-W涂层电弧烧蚀面积增大明显,呈现出2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。Mo-W喷涂层抗电弧烧蚀性能优于纯Mo喷涂层。

Mo-W coating was prepared by supersonic plasma spraying technology on the surface of 45 CrNiMoVA steel. The bonding strength of the coating was tested. The electrical conductivity of the coating was tested by a resistance tester. The arc erosion test of the Mo-W coating with different discharge currents in atmosphere was carried out by a 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 Mo-W coating prepared by the supersonic plasma spraying process has good adhesion with the substrate, and the conductivity is only 6.12%IACS. Porosity is the main reason for the lower conductivity of the coating.The oxidation has little influence on the conductivity of Mo-W coating. As the discharge current increases, the Mo-W coating arc erosion area increases significantly and the erosion coating exhibits two different erosion morphologies;the larger the porosity and the smaller the surface roughness, the worse the arc erosion resistance of the coating. The arc erosion resistance of Mo-W coating is better than that of pure Mo coating.