【摘要】 镀锌板经单纯的有机、无机钝化均不能满足工业生产需求,而目前在2种有机钝化剂中添加无机钝化剂的研究鲜见报道。将KH560和KH858 2种有机硅烷复合作为有机硅烷钝化液,再添加CoSO4·7H2O复配,用其浸涂热镀锌板制成钴盐有机硅烷复合转化膜。采用Tafel极化曲线、交流阻抗、盐水浸泡和中性盐雾试验研究钴盐加入前后转化膜耐蚀性的变化。结果表明:相比于有机硅烷转化膜,加入钴盐后形成的钴盐有机硅烷复合转化膜阻抗增大,自腐蚀电流密度减小,耐蚀性明显改善,中性盐雾腐蚀72 h后腐蚀面积仅7%。更多还原

【Abstract】 CoSO₄·7H₂O was added into the silane passivation solution consisting of KH560 and KH858 silane coupling agents,and resultant compounded passivation solution was then dip-coated onto the surface of hot-dip galvanized steel sheet to afford silane conversion coatings doped by cobalt salt.The corrosion resistance of the conversion coatings before and after doping with cobalt salt was evaluated based on measurement of Tafel curves and alternating current impedance spectra as well as immersion tests in saline water and neutral salt-spray tests.Results showed that,as compared with the silane conversion coating without cobalt salt dopant,the one doped with cobalt salt possessed significantly reduced corrosion current density and greatly improved corrosion resistance,and its corroded area was as low as 7%after 72 h of neutral salt-spray test.更多还原