电子工业用镍包铜粉的工艺及性能研究

采用不同粒度的片状铜粉,以次磷酸钠作为还原剂,通过化学镀镍制备出性价比较高的、具有较好电磁屏蔽性能的镍包铜粉。讨论了铜粉粒径及镍含量对镍包铜性能的影响,结果表明,粒径大的铜粉较易进行化学镀镍,而镍包铜粉电阻随铜粉粒径减小而增大;随镍含量的减少,镍包铜粉的颜色变浅,电阻减小。SEM照片显示,镍包铜粉形貌较好,片状化程度较好。镍含量为30%时镍包铜粉磷含量较低,实际成分含量与理论相符,松装密度及导电性较好,是理想的电磁屏蔽材料。

Process and properties of nickel coated copper powder used in electronic industry

By electroless nickel plating,nickel coated copper powder with relatively higher performance/price rate and good electromagnetic screen ability was prepared using sodium hypophosphite as reducer and flaky copper power of different granularity.The influences of copper powder's diameter and nickel content on the performance of the nickel coated copper powder were discussed.The results show that electroless nickel plating is easier to be realized for the copper powder with greater granularity,while the electric resistance of nickel coated copper powder increases with decreasing copper powder's granularity;The color and resistance of nickel coated copper powder become light and smaller respectively with reduced nickel content.SEM photos reveal that the nickel coated copper powder has satisfactory morphology and flaky degree.The nickel coated copper powder obtained with 30% of nickel content is an ideal electromagnetic screen material because of its low phosphor content,a practical value of composition content consistent with theoretical value,and good loose loading density and conductivity.