小型铁基粉末冶金件的化学镀镍工艺

Electroless nickel plating technics of small iron-based powder metallurgy components

根据铁基粉末冶金件的结构特点和用户对零件性能的特殊要求，对其化学镀镍前处理工艺进行了优化，获得了最佳工艺流程：有机溶剂除油-在270～300℃下烘烤后用硬脂酸锌封孔-滚光、磨光-超声波脱酯-5％～8％（质量分数）的盐酸浸蚀30～40s。研究了预镀铜、化学镀镍及后处理等工艺对镀层性能的影响。

According to the structure characteristic of iron- based powder metallurgy components and the special request of user on parts performance, the pretreatment technics of electroless nickel plating were optimized. The optimized process flow was gained as follows： solvent degreasing -pore-sealing by zinc stearate after baking at temperatures of 270- 300℃—barrel polishing, wear polishing—ultrasonic degreasing—Acid etching by 5 % - 8 % （mass fraction） of hydrochloric acid for 30 -40 s. The influences of technicses of copper preplating, electroless nickel plating and posttreatment etc, on coating＇ s performance were stu-died.