利用线性电势扫描法和循环伏安法分别讨论了配位剂对Fe^2+、Ni^2+、Cr^3+单独电沉积和Fe-Ni-Cr合金共沉积电化学行为的影响,并采用SEM和XRD技术对舍金镀层表面形貌和结构进行了表征。实验结果表明,有配位剂存在时,Fe^2+单独沉积电势向正方向移动,Ni^2+单独沉积电势向负方向移动,且两者析出电势均在-0.85V附近;在简单铬离子水溶液中,不能沉积出金属铬,有配位剂存在时,Cr^3+溶液可以得到金属铬;在合金镀液中,没有配位剂存在时,不能得到Fe—Ni-Cr合金镀层,有配位剂存在时,可以得到晶粒平均尺寸为87nm的光亮致密的Fe—Ni—Cr合金镀层,说明配位剂能与Cr^3+在电极表面形成电活性配合物,使Cr^3+容易在电极上放电,另一方面说明Ni、Fe的析出对Cr的沉积有诱导的作用,使铬在合金镀液中沉积电势正移,实现Fe-Ni—Cr合金共沉积。
Electrochemical behaviors of electrodepositing Fe^2+, Ni^2+, Cr^3+ solely and Fe-Ni-Cr alloy have been studied by linear potential scan and cyclic voltammetry and the alloy plating were characterized by means of SEM and XRD in this study. The experimental results show that the deposition potential of Fe^2+ moves positively and the deposition potential of Ni^2+ moves negatively, but their deposition potentials are about -0. 85V when the complexant is added. The chrome can not be deposited in the single chrome ion solution without complexant, however it can be deposited in the solution contained complexant. The Fe-Ni-Cr alloy plating can not be gained from the solution without complexant, whose the average size of crystal grain is 87nm is gained in the plating solution with complexant, which indicate that a electro-activity complex of Cr^3+ and complexant forms on the electrode surface, resulting in Cr^3+ discharge easily. Moreover, it indicates that chromium electrodepositing is induced by Ni and Fe deposition, which helps the Cr deposition potential move to the positive direction and carry out Fe-Ni-Cr alloy electrodepositing.