恒流微弧氧化工艺参数对膜层表面粗糙度的影响

铝合金微弧氧化膜表面粗糙度的影响因素较多,膜表面的粗糙度对其应用有影响,过去研究甚少,为了找出改善和控制膜层表面粗糙度的方法,在恒流模式下利用双极性脉冲电源对LD10铝合金试件进行了微弧氧化处理,采用TR200粗糙度仪检测了膜层表面粗糙度,分析了加工参数对膜层表面粗糙度的影响.结果表明:在一定范围内单独缩短微弧氧化时间、减小正向或负向电流密度、提高频率、降低占空比,都有利于降低膜层表面粗糙度;但温度过高或过低都不利于降低膜层表面粗糙度,只有在30～40 ℃的工作液中处理获得的膜层表面粗糙度才最佳.在30 ℃、电流密度10 A/dm2、脉冲频率200 Hz、占空比24%时,可获得最佳表面粗糙度(Ra 1.2 μm)的硬质微弧氧化膜层.

Effect of Micro-Arc Oxidation Parameters in Constant Current Mode on the Surface Roughness of Alumina Coatings

A power supply equipped with positive and negative pulses was used to treat LD10 aluminum alloy specimen in constant current mode. The surface roughness of the alumina coatings obtained at different parameters was measured using a TR200 surface roughness tester. And the influence of processing parameters on the surface roughness of the coatings was investigated. Results indicate that separately reducing processing time, positive current density, negative current density, and duty ratio, or elevating frequen...