超厚镀钯技术在光电经纬仪上的应用

摘要

以黄铜为基材,研究了吡啶添加剂-氨盐体系的电镀钯工艺,分析了钯盐、氯化铵、吡啶添加剂质量浓度,温度及pH对镀液和镀层质量的影响.在Pd(NH3)2Cl220 g/L,NH4Cl 15 g/L,NH3·H2O 35 mL/L,吡啶添加剂25 g/L,pH 7～8,温度25～35℃和电流密度0.4～0.5 A/dm2的条件下,获得了厚度达35 μm的光亮钯镀层.该镀层与基体结合力良好,能满足光电经纬仪的工作要求.%A Pd plating process based on the bath containing pyridine additive and ammonium salt was studied with brass as substrate. The effects of mass fractions of Pd salt, NH4Cl and pyridine additive as well as temperature and pH on the bath and deposit quality were analyzed. Bright and 35 μm-thick Pd coatings can be obtained under the following conditions: Pd(NH3)2Cl2 20 g/L, NH4Cl 15 g/L, NH3·H2O 35 mL/L, pyridine additive 25 g/L, pH 7-8, temperature 25-35 ℃, and current density 0.4-0.5 A/dm2. The results showed that the Pd coating has good adhesion and is suitable for optoelectronic theodolite.