微弧氧化工艺对锆合金表面陶瓷层厚度和形貌的影响

Effect of Process Parameters on Thickness and Morphology of Micro-Arc Oxidation Ceramic Coating of Zirconium Alloy

在磷酸盐电解液体系中制备了Zr-4合金的微弧氧化陶瓷层,研究了正负向电压、频率及氧化时间等工艺参数对陶瓷层的厚度和表面微观形貌的影响。结果表明:综合对陶瓷层厚度和表面质量的影响因素,适宜的工艺参数为正向电压520V,负向电压160V,频率250Hz,氧化时间10min。在此条件下,可得到厚度50μm左右的表面状况较好的陶瓷层。较高的正向电压和较长的氧化时间有利于提高膜层的厚度,而高的正负向电压、低频率和长时间的氧化,容易形成带有较大孔洞的火山状突起和穹状表面,膜层出现裂纹并且崩离的趋势增大,因此锆合金的微弧氧化需要有适当的工艺参数配合。

The ceramic coating was prepared by micro-arc oxidation on Zr-4 alloy in phosphate system electrolyte, the effect of positive voltage, negative voltage, power frequency and oxidation time on the thickness and the surface micro-morphology of ceramic coating was studied. The results indicate that the suitable process parameters to obtain well combine properties of thickness and surface quality of ceramic coating is as follows： positive voltage 520V, negative voltage 160 V, frequency 250Hz and oxidation time 10 min, by which the ceramic coating of about 50μm in thickness with advisable surface is formed. The higher positive voltage and longer oxidation time benefits the increase of the thickness, but higher positive and negative voltage, lower frequency as well as longer oxidation time cause easily the obvious volcano-shape bulge with bigger pore and quaquaversal surface which results in crack and break of the coating, so the process parameters must match well.