镁合金表面等离子喷涂Al涂层及激光重熔研究

Study of Plasma-Sprayed Al Coating on Mg Alloy and Laser-Remelting

摘要:

利用等离子喷涂技术在镁合金表面制备了Al涂层，并通过激光对该涂层进行重熔处理。利用SEM、金相显微镜、XRD、万能材料试验机、盐雾腐蚀试验等分析测试手段研究了该涂层在激光重熔前后的变化。结果表明：镁合金表面等离子喷涂Al涂层经激光重熔后，涂层和基体之间的结合由机械结合转变为冶金结合，结合强度由20.96 MPa提高到22.13 MPa；涂层相组成不变；但出现了较多的孔隙和空洞，孔隙率由4.6%增大到7.5%，涂层耐盐雾的时间由900 h降低到264 h。

Abstract:

Al coating on Mg alloy was prepared by plasma spraying technology, and it was then remelted by laser beam. The change of the coating before and after laser remelting was investigated using SEM, OM, XRD, tensile machine and salt spraying test. The results show that after laser remelting, the mechanical bond between the substrate and the coating changes to metallurgic bond and the adhesion strength is increased from 20.96 MPa to 22.13 MPa. The phase constituent keeps the same. Lots of pores occur in the coating and the porosity ratio is increased from 4.6% to 7.5%. The corrosion time is decreased from 900 h to 264 h.