复合化学镀几个关键工艺因素研究

Study on Some Critical Factors for the Electroless Composite Plating

为使化学镀镍-磷合金镀层具有更高的硬度，进一步提高其耐磨、耐蚀的性能，利用化学复合镀技术制备出镍-磷-纳米Al2O3复合镀层，并研究了pH值、温度、固体颗粒含量等几个关键工艺因素对镀液的稳定性、镀速和镀层磷含量的影响，特别是对固体颗粒的分散方法进行了较深入的研究。结果表明，在合适的工艺条件下，即当镀液的pH值为4．4～4．6，施镀温度（90±2）℃，颗粒含量12～14g／L，采用机械搅拌加超声波分散，机械搅拌转速200～250r／min，超声波分散频率40kHz时，可获得性能良好的复合镀层。

In order to make the electroless Ni-P coating possesses the better hardness, wear and corrosion resistance, Ni-P-nanometer A12 03 composite coating is prepared by electroless composite plating. The influences of some critical factors, such as temperature, pH value and the ratio of powder in the solution, on the solution stability, the deposition rate and the content of phosphate in the coating are studied, especially, the various dispersing methods for the powder are deeply studied. The results indicate that the electroless composite coating with good properties can be obtained under the proper technical conditions as following ： pH value in the solution is 4.4 ～ 4.6, the temperature of the electroless plating is 90 ± 2℃, the concentration of A1203 particle is 12 ～ 14g/L, and using the mechanical stirring of 200 ～ 250r/min as well as the ultrasonic dispersing of the frequency 40kHz.