化学镀镍钨磷合金过程中的析氢行为和沉积机理

Behavior of hydrogen evolution and rate determining by electrochemical method during electroless Ni-W-P alloys plating

摘要: 本文研究了化学镀镍钨磷合金过程中的析氢行为,发现总析氢量大于金属沉积的量,即产生氢气的法拉第电流大于金属沉积的法拉第电流.认为镍钨磷合金化学沉积的机理是镍、钨、磷、氢的竞争放电,且除金属沉积时伴随着等量的析氢外,氢也能单独析出.温度、pH值和亚磷酸根浓度对合金沉积速度和合金成分的影响表明,该体系能在很宽的工艺范围内获得光亮、均匀、结合力良好的镀层.用塔菲尔斜率分析法测量的合金沉积速度与重量法测得的相一致,说明电化学方法可以用于确定化学镀的沉积速度.

Abstract: In the presented paper,the behavior of hydrogen evolution was investigated during electroless Ni-W-P alloy plating.The mechanism of Ni-W-P alloy deposition is a competition among the reduction of Ni²⁺,W⁶⁺,P⁺,H⁺.Besides hydrogen ions reduce separately,the same faradic amount hydrogen evolves with Ni-W-P alloy deposition together.Under most temperatures and pH values investigated bright and coherent coatings uniform in appearance have been produced.The deposition rate measurement by the means of Tafel slope analysis shows an agreement with gravimetric data.