石墨粉末化学镀镍工艺研究

Study on process of electroless nickel plating for graphite powder

导电填料是构成高性能电磁波屏蔽材料和吸收材料的主要原材料。对石墨粉末化学镀镍提出采用含有浓 硫酸和K2Cr2O7的溶液进行氧化、含有SnCl2的溶液进行敏化以及含有PdCl2的溶液进行活化的前处理工艺,在粒径为 5～20μm的石墨粉末表面得到了均匀的高镍(wNi>90％)低磷合金镀层,解决了石墨粉末化学镀镍难的问题。讨论了镀 液中各组分含量、温度及搅拌速度对化学镀镍的影响。石墨粉末经该化学镀镍工艺处理后导电性及电磁屏蔽性能良好, 是较好的电磁屏蔽用导电填料。

Conductive filler is the main raw material of high-performance electromagnetic shielding material. Following the pretreatment of oxidation with solution containing sulfuric acid and K2Cr2O7, sensitization with solution containing SnCl2 and activation with solution containing PdCl2 in sequence, electroless nickel plating was carried out on graphite powder. A uniform alloy deposit with high nickel and low phosphorus was thus obtained on graphite powder with a diameter of 5 - 20 μm, which contains nickel over 90% by weight, thereby solving the difficult problem of electroless nickel plating on graphite powder. The influences of each component content in plating bath, temperature and stirring speed on electroless nickel plating were discussed. The graphite powder treated by the electroless nickel plating process mentioned above has good conductivity and electromagnetic shielding performance, and so can be used as good conductive filler of electromagnetic shielding.