作　　者： ; ; ; ;

机构地区： 华南理工大学材料科学与工程学院

出　　处： 《铸造技术》 2012年第5期565-568,共4页

摘　　要： 采用不同的植酸水溶液对压铸镁合金AZ91D进行化学转化处理,通过SEM、EDS、浸泡法研究了添加剂及pH值对转化膜膜厚、形貌及耐蚀性能的影响。结果表明:pH值由3增大到5时,转化膜的膜厚和耐蚀性呈先增大后减小的趋势,当pH=4时膜厚达到最大值,且耐蚀性能最好。加入添加剂后所得到的化学转化膜的膜厚和耐蚀性能都相对未加添加剂的化学转化膜有所增大,同时加入添加剂后的转化膜表面裂纹明显变小。在选用Ca(NO3)2、偏钒酸铵、酒石酸钠作添加剂的植酸溶液中所形成的转化膜的性能最佳。 The die casting magnesium alloy AZ91D was treated in solutions of different phytic acid.The influence of additives and pH values on the thickness,morphology and the corrosion resistance of conversion coatings was investigated by SEM,EDS,and Soaking method.The results show that,when pH value increased from 3 to 5,the thickness and corrosion resistance of the conversion coatings increases firstly,and then decreases.When pH=4,the thickness reaches the maximum,and the corrosion resistance is the best.The coatings formed in acid solutions with additive are thicker than that in the pure acid solutions,and also the size of cracks of the fomer is smaller.The performance of the conversion coating formed in the phytic acid solution contained the additives of Ca（NO3）2,ammonium metavanadate and sodium tartaric is the best.

关 键 词： 化学转化处理 植酸 压铸镁合金 添加剂 转化膜

领　　域： [金属学及工艺] [一般工业技术] [金属学及工艺]