AC7A新型铝合金硫酸草酸阳极氧化研究

Process Research of Sulphuric-Oxalic Acid Anodizing on AC7A Aluminum Alloy

为了提高铝合金阳极氧化膜的性能,采用硫酸和草酸的混合溶液(质量浓度比10:1)对AC7A铝合金进行了阳极氧化处理,并对阳极氧化的工艺参数进行了优化。实验结果表明:AC7A铝合金硫酸草酸阳极氧化的氧化膜为多孔蜂窝状结构,其硬度和厚度均随温度的升高而减小;在电流密度3.0 A/dm2、电解液温度2℃、氧化时间1 h的工艺参数下,AC7A硫酸草酸阳极氧化膜层硬度可达471 HV50,厚度可达75μm。说明采用质量浓度比10∶1的硫酸草酸混合溶液对AC7A铝合金进行阳极氧化处理,可保证氧化膜的硬度和厚度满足使用要求,提高铝合金构件的使用寿命。

In order to improve the performance of anodic alumina,AC7A aluminum alloy was anodized in sulphuric-oxalic acid（concentration ratio of 10∶1）,and the anodizing process parameters were optimized.The experiment results showed that the oxide film is porous honeycomb structure,the hardness and thickness of the oxide film decreased with the increasing of the solution temperature;Under the process parameters（i=3.0 A/dm^2,t=2 ℃,1 hour anodic oxide）,the hardness of the film was 471 HV50,and the thickness of the film was 75 μm.The results showed that the hardness and thickness of the oxide film met the requirement of the AC7A aluminum alloy which was anodized in sulphuricoxalic acid（concentration ratio of 10∶1）,and the service life of the aluminum alloy components were improved.