The effects of rare earth element cerium on composition and electrochemical characteristics of electroless Co-Ni-B alloy were studied in this paper. The alloy component was analyzed using Inductively Coupled Plasma (ICP) . The plating rate is was determined by electronic balance. The cathode polarization curves and cyclic voltammogram during the electroless deposition were tested by LK998 Ⅱ model electrochemical analytical system. The results show that rare earth element Ce can co-deposit with cobalt-based alloy, and with mass increase of Ce added in aqueous solution, the contents of Co, Ni, Ce in alloy increase and the content of B decreases. Ce can increase deposition rate of alloy in some range. The rare earth makes deposition potential move to positive direction and makes polarizability decrease.
利用等离子发射光谱仪、电子能谱仪、X 射线衍射仪、透射电子显微镜等 ,考察引入稀土金属Ce后化学镀Co Fe B合金镀层的化学成分和晶体结构。结果表明 ,随镀液中稀土金属Ce添加量的增加 ,镀层中Ce的含量先增后降 ,在Ce =1 0g/L时达到最大值。Ce的介入使化学镀Co Fe B Ce合金镀层中B含量减少 ,Co和Fe含量增加 ,并使非晶态结构的合金镀层转化为微晶态结构。
研究了磁场条件下化学镀Co- Ni- B -Ce合金镀层的微观表面形貌、显微硬度和磨损体积。结果表明,化学镀Co- Ni -B合金镀层表面由“圆锥峰”构成,表面较为平整,添加稀土Ce后,镀层变得凹凸不平;在外加磁场下施镀,镀层表面起伏更大。镀液里添加Ce以及在磁场条件下,明显地提高了Co -Ni -B合金镀层的显微硬度和耐磨性,随镀液中Ce添加量增加,合金镀层的硬度和耐磨性都是先增加后降低,当镀液里Ce的添加量为0. 8g/L时,硬度和耐磨性均达到了峰值。
利用恒电位仪、等离子发射光谱仪、电子能谱仪、X射线衍射仪、透射电子显微镜等考察和分析了引入稀土金属La时化学镀Co Fe B合金的阴极极化曲线、沉积速度、化学成分和晶体结构。结果表明 ,稀土La的介入明显改善了化学镀Co Fe B合金的静止电位和极化度 ,随镀液里稀土金属La添加量的增加 ,合金的沉积速度和镀层中La的含量都是先增后降 ,且都在La加入 0 6g·L- 1 时达到最大值。稀土La的介入使化学镀Co Fe B La合金镀层中B的含量减少 ,Co和Fe的含量增加 ,并使具有非晶态结构的化学镀Co Fe B合金转化为晶态结构的化学镀Co Fe B La合金。
