稀土镧对化学镀Co-Ni-B合金沉积速度的影响

Effect of rare earth lanthanum on deposition rate of electroless Co-Ni-B alloy

向Co-Ni-B合金镀液中加入了稀土La.以沉积速度为评价标准,通过正交试验得到其适宜的镀液基础配方为:10～13 g/L CoCl2 * 6H2O,2.3～4.9 g/L NiCl2 * 6H2O,0.6～1.2 g/L NaBH4,55～65 g/L Na2C4H4O6 * 2H2O,12～16 g/L NH4Cl,1～2 g/L稳定剂,0.8～1.2 g/L La,θ 50～80 ℃,pH 14,负载因子 0.4～0.8 dm2/L.在此基础上,研究了La对沉积速度的影响,结果表明,La能提高Co-Ni-B镀液稳定性、沉积速度,改善镀层表面质量.在一定范围内,La的加入量越多,效果越明显;La的适宜加入量为0.8 g/L.同时探讨了主盐浓度、还原剂浓度、络合剂浓度、缓冲剂浓度对沉积速度的影响.

The rare earth element lanthanum was added to the Co-Ni-B alloy bath. Using deposition rate as evaluation criterion, the optimal basic formulation with orthogonal test was obtained as follows： 10 ～ 13 g/L CoCl2·6H2,2.3 ～ 4.9 g/L NiCl2·6H2O,0.6 ～ 1.2 g/L NaBH4,55 ～65 g/L Na2C4H4O6·2H2O,12 ～ 16 g/L NH4Cl,1 ～2 g/L stabilizer, 0.8 ～ 1.2 g/L La,θ 50 ～ 80 ℃ , pH 14, load factor 0.4～ 0.8 dm^2/L. On the basis of this, the influence of lanthanum on deposifion rate was studied. The results show that lanthanum can remarkably improve the stability of plating bath, deposition rate and depositg surface quality. Within a certain range, the more the addition of lanthanum is in plating bath, the more obviously it has favorable effects on alloy ; The optimum addition of La is 0.8 g/L. The influences of content of main salt, reducing agent, complexing agent and buffering agent on deposition rate were also discussed.