Electrochemical behaviors of Zn-Fe alloy and Zn-Fe-TiO2 composite electrodeposition in alkaline zincatesolutions were studied respectively by the methods of linear potential sweep and cyclic voltammetry. From the re-s...Electrochemical behaviors of Zn-Fe alloy and Zn-Fe-TiO2 composite electrodeposition in alkaline zincatesolutions were studied respectively by the methods of linear potential sweep and cyclic voltammetry. From the re-sults it can be concluded that Zn shows under potential deposition, Zn-Fe alloy codeposition is anomalous codeposi-tion and Zn-Fe alloy cathode polarization is increased with the introduction of additive. From the view point of elec-trochemistry, the reasons that the content of Fe in the Zn-Fe coating changes with the composition of the electrolyteand the process conditions altering and the relationship between the content of Fe and the appearance of the coatingare interpreted. The cathode polarization of Zn-Fe alloy codeposition is enhanced obviously with addition of additive.In the course of composite electrodeposition, TiO2 has less promotion to electrodeposition of zinc ions than to iron i-ons, while the electrodeposition of iron ions improves the content of TiO2 in composite coating, which is inagreement with the results of process experiments.展开更多
通过改变工艺条件,可以从碱性溶液中获得含 Fe0.4~0.8%的 Zn-Fe合金镀层。试验表明这种镀层的耐蚀性是普通镀锌层的2倍。含 Fe 量不同的镀层其耐蚀性也不同。含 Fe 在0.4~0.8%的镀层在5%NaCl 溶液中在稳定电位条件下处于钝化区,而且...通过改变工艺条件,可以从碱性溶液中获得含 Fe0.4~0.8%的 Zn-Fe合金镀层。试验表明这种镀层的耐蚀性是普通镀锌层的2倍。含 Fe 量不同的镀层其耐蚀性也不同。含 Fe 在0.4~0.8%的镀层在5%NaCl 溶液中在稳定电位条件下处于钝化区,而且镀层的极化电阻比较大,是镀锌层的2倍以上,而镀锌层在同样溶液中处于活化溶解区,有很大的溶解电流,而且极化电阻较小。腐蚀后形貌观察也表明 Zn-Fe 合金镀层与镀锌层的特征不同,呈花球状形貌。正是由于上述差异决定了 Zn-Fe 合金镀层的耐蚀性是优良的。展开更多
基金The Research Project from Department of Science and Technology of Shandong Province(2012GGA01012)the Scientific Research Foundation for the Returned Overseas Chinese Scholars of State Education Ministry(2004-527)
文摘Electrochemical behaviors of Zn-Fe alloy and Zn-Fe-TiO2 composite electrodeposition in alkaline zincatesolutions were studied respectively by the methods of linear potential sweep and cyclic voltammetry. From the re-sults it can be concluded that Zn shows under potential deposition, Zn-Fe alloy codeposition is anomalous codeposi-tion and Zn-Fe alloy cathode polarization is increased with the introduction of additive. From the view point of elec-trochemistry, the reasons that the content of Fe in the Zn-Fe coating changes with the composition of the electrolyteand the process conditions altering and the relationship between the content of Fe and the appearance of the coatingare interpreted. The cathode polarization of Zn-Fe alloy codeposition is enhanced obviously with addition of additive.In the course of composite electrodeposition, TiO2 has less promotion to electrodeposition of zinc ions than to iron i-ons, while the electrodeposition of iron ions improves the content of TiO2 in composite coating, which is inagreement with the results of process experiments.