阳极氧化对压铸铝合金电解着黑色工艺的影响

Influence of anodizing on electrolytic black colouring technique of die-casting aluminium alloy

选择压铸铝合金ADC12为研究对象,确定黑色为着色系,在确定的电解着色工艺下,重点探讨溶液种类、浓度和温度等阳极氧化工艺参数对黑色膜完整性、色泽度的影响。通过系列试验,优选工艺参数如下:以水磨、抛光、除油为前处理;在直流电压20 V下,于20%H2SO4溶液中进行阳极氧化,温度为40℃,反应时间为40 min,可获得黑度系数达0.9且膜色均匀的染色膜层。结合基体显微组织分析,认为要改善膜层着色效果,宜先通过有效的熔体处理,改善基体组织形态。

Die-casting aluminium alloy ADC12 was adopted to study black colouring of electrolytic colouring process. The effect of anodizing process parameters of the type, concentration and temperature of colouring solution on the integrity and colour degree of black film was focused. Through a series of tests, optimized process parameters were ascertained. Pre-treatment of wet milling, polishing and degreasing was conducted. Anodic oxidation in 20% H2SO4 solution at 20V, 40℃ for 40 minutes, a uniformly stained coloured membrane with a blackness coefficient of 0.9 was obtained. Combining matrix microstructure analysis, it is indicated that effective melt treatment can be adopted to improve the microstructure to form better coloured film.