乳酸络合剂化学镀镍锡磷合金的研究

Study on Electroless Plating of Ni-Sn-P Alloy with Lactic Acid as Complexing Agent

研究了乳酸作络合剂的酸性镀液中，络合剂添加量对镀液稳定性的影响，以及硫酸镍、四氯化锡、还原剂含量对化学镀镍-锡-磷合金镀速和镀层成分的影响。研究结果表明：在保证镀液已有与镍盐摩尔比为1：3的络合剂外，需要再加入按与锡盐摩尔比为1：7的量计算的络合剂，才能保证镀液足够的稳定性：在镀液中硫酸镍质量浓度为30g／L，四氯化锡为20g／L，次亚磷酸钠为30g／L时镀速较快：在pH值为4．8，85～90℃的操作温度下，所获镀层中锡的质量分数w（Sn）可达7．1％。

This paper studied the effect of addition amount of lactic acid as complexing agent on the stability of the acidic plating solution and the effect of concentrations of NiSO_4 SnCl_4 and NaH_2PO_2 in solution on the deposition rate and composition of plating layer.The results showed that besides the available complexing agent in plating solution guaranteeing its mole ratio to nickel salt to be 1:3, it is necessary to add another amount of complexing agent according to the mole ratio of 1:7 to the tin salt for the full stability of plating solution, the deposition rate becomes faster when the concentrations of NiSO_4, SnCl_4 and NaH_2PO_2 reach 30g/l, 20g/l and 30g/l,respectively, and the concentration of Sn can reach 7. 1wt% at the conditions when pH=4.8 and temperature is 85-90℃。