为了获得无氰镀镉-钛合金的最佳后处理工艺,利用金相显微镜、电化学工作站和盐雾试验测试了三种钝化膜的外观及耐蚀性,并进行了比较.实验结果显示,三种钝化工艺获取的钝化膜经96h中性盐雾试验后,均未出现白锈;电化学测试结果显示低铬钝化工艺获取的钝化膜自腐蚀电流密度最大,重铬酸钠钝化工艺获取的钝化膜自腐蚀电流密度最小.从环保和耐蚀性方面考虑,建议选用重铬酸钠+硝酸钝化工艺作为无氰镉-钛合金镀层的后处理工艺.%In order to obtain the best post treatment process for non cyanide Cd-Ti alloy coating,the appearance and corrosion resistance of three kinds of passivation film were tested and compared by means of metallographic microscope,electrochemical workstation and salt fog experiments.Experimental results showed that no white rust occurred in all the passivation films after 96 hours neutral salt spray tests;electrochemical testing results showed that the self corrosion current density of the passivation film obtained from low chromium passivation process was the largest,and the self corrosion current density of the passivation film obtained from sodium dichromate passivation process was the smallest.Taking environmental protection and anti-corrosion performance into consideration,it is suggested that sodium dichromate + nitrate passivation process should be selected as the post-treatment process for non cyanide Cd-Ti alloy coating.
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