铝及其合金浸锌溶液用表面活性剂的优选

OPTIMIZATION OF SURFACE ACTIVE AGENTS OF ZINKING BATH FOR ALUMINUM AND ITS ALLOYS

利用CHI630电化学分析测试仪测试了在浸锌溶液中加入不同表面活性剂及加入不同含量的最优表面活性剂后试片活化电位随浸锌时间的变化曲线和浸锌后的试片在3.5%NaC l溶液中的极化曲线,对其耐蚀性能进行了研究.结果表明,表面活性剂可以提高浸锌后试片的稳定电位,提高浸锌层在3.5%NaCl溶液中的耐蚀性;并确定了表面活性剂A是较适宜的浸锌溶液中的表面活性剂,其最佳用量为0.1 g/L^0.15 g/L.同时,利用SEM、EDS对浸锌层、断面、镀镍层的形貌和成分进行了分析.镀层结合力合格.

Aluminum and its alloys were zincified in a bath with different surfactants, during the process the E-t curves were monitored. Then the polarization curves of the zinc coated Al-alloys were measured in 3.5% NaCl solution by means of a CHI 630 electrochemical tester. It could be concluded from potential and corrosion resistance of zinc coatings that surface active agent could improve the stable potential and the corrosion resistance of the zinc coated Al-alloy in 3.5 % NaCl solution as well. The better surface active agent is surfactant A,and the best amount of which is 0.1 g/L -0.15 g/L. Scanning electron microscope （SEM） and energy dispersive spectrum （EDS） were used to analyze the micromorphology and composition of zinc and EN deposits. The adhesion of EN deposits to the substrate is qualified. The role of surface active agent is also discussed.