铝合金表面微弧氧化制备陶瓷层的最佳工艺优化及耐腐蚀性能研究

Study on Optimum Process Optimization and Corrosion Resistance of Ceramic Layer Prepared by Micro-Arc Oxidation on Surface of Aluminum Alloy

以7A52铝合金为对象,进行微弧氧化陶瓷层制备工艺优化及耐腐蚀性能研究。利用响应曲面法设计微弧氧化试验,在硅酸盐电解液体系下,研究电压、频率、石墨烯添加剂浓度对微弧氧化陶瓷层的厚度和孔隙率的影响,采用Quadratic模型进行数据拟合,Criteria进行预测分析,并对预测参数及响应值进行试验验证。经响应曲面分析,当预测电压为465.52 V,频率为102.66 Hz,石墨烯浓度为0.38 g/L时,获得最佳孔隙率为9.99261%,最佳陶瓷层厚度为15.4277μm。以该参数进行试验,实测孔隙率为9.6%,厚度为12.76μm,该参数下制备的微弧氧化陶瓷层经电化学测试,腐蚀电位明显增大,腐蚀电流降低,具有较好的耐腐蚀性能。

Taking 7 A52 aluminum alloy as the object,the preparation process optimization and corrosion resistance research of micro-arc oxidation ceramic layer were carried out.The response surface method was used to design the micro-arc oxidation test,and the effects of voltage,frequency,and graphene additive concentration on the thickness and porosity of the micro-arc oxidation ceramic layer were studied in the silicate electrolyte system.Furthermore,the Quadratic model was used to fit the data,the Criteria was used to conduct predictive analysis and perform experimental validation of predictive parameters and response values.The response surface analysis showed that when the conditions were 465.52 V of predicted voltage,102.66 Hz of frequency and 0.38 g/L of graphene concentration,it possessed 9.99261%of the optimal porosity and 15.4277μm of the optimal ceramic layer thickness.Experiments with the above conditions showed that the measured porosity of as-prepared layer was 9.6%,and the thickness was 12.76μm.Moreover,the electrochemical tests on the micro-arc oxidation ceramic layer prepared under this conditions indicated that the corrosion potential increased significantly,and the corrosion current decreased,which inferred that the layer had good corrosion resistance.