电镀镍铬合金的研究进展

Recent Advance in Study on Electrodeposition of Nickel Chromium Alloys

针对近年来电镀镍铬合金的研究概况以及存在的主要问题,阐述了Cr3+配位化学的特点,即Cr3+配位化合物在热力学上的稳定性和动力学上的惰性对镀液的影响。分析了镀液中溶剂、主盐、配位剂、缓冲剂、导电盐和表面活性剂等组分的作用及如何选择恰当的比例。介绍了电流密度、pH值、温度和搅拌等工艺参数对镀层成分和质量的影响。论述了镍铬合金镀中的阳极和阴极过程,探讨了在阳极过程中生成的氯气和在阴极过程中生成的Cr2+对沉积过程的作用。最后,介绍了镍铬合金镀层的组织及热处理对镀层性能的影响。

A review was given on the recent advance in study of electrodeposition for Ni-Cr alloys.The characteristics of coordinative chemistry of Cr (Ⅲ),namely,the effects of its thermodynamics stability and dynamics inertia on the plating bath stability and performance were summarized.The actions of the components such as dissolvent,buffering agent,complexing agents,etc.,in the plating bath,were discussed,while an analysis was made as well on the determination of their concentration ratios in the bath.Moreover,the effects of the deposition variables including current density,pH value,temperature,and stirring on the composition and quality of the deposited coatings were analyzed.The anode and cathode processes in the codeposition of Ni-Cr alloys were explored,with the focus to be placed on the actions of Cl-2 generated in the anode process and Cr 2+ generated in the cathode process.In addition,a primary analysis was made on the effects of microstructures and heat-treatment on the properties of the electrodeposited Ni-Cr alloy coating.It was pointed out that the composition and quality of the electrodeposited Ni-Cr alloy coating were highly dependent on the plating parameters and the post-heat-treatment process.It would be imperative to pursuit more cost-effective and environmentally acceptable electrodeposition processes for Ni-Cr alloy coating.