机械研磨化学复合镀Ni-P-Al2O3工艺

采用机械研磨化学复合镀工艺在模具锌合金表面获得Ni-P-Al2O3复合镀层,研究镀液成分、纳米Al2O3加入量和工艺条件对镀速的影响.结果表明:硫酸镍、次亚磷酸钠和纳米Al2O3在镀液中的含量均存在极限值,超过极限值后镀速开始下降;在镀液不发生分解时,pH值和温度的提高使镀速迅速上升;机械研磨使镀速显著减小,但玻璃球直径大小对镀速影响不大.优化工艺条件下镀速可达12～13μm/h,在此工艺下获得的镀层硬度高、耐蚀性好.

Technology of mechanical attrition and chemical composite plating with Ni-P-Al2O3

Depositional Ni-P-Al2O3 coatings was obtained on mould surface of zinc alloy by means of mechanical attrition and chemical composite plating technique,and the effect of bath ingredients,nano Al2O3 addition content,and process conditions on the deposition rate was investigated.The result showed that the nickel sulfate,sodium hypophosphite and nano-Al2O3 content in the bath were limited and over the limiting value the plating rate began to decline.And the deposition rate increased rapidly with the bath temperature and pH value as there was no bath decomposition,but it reduced markedly due to mechanical attrition.The size of the glass ball had less influence on it.The peak value of the deposition rate was 12~13 μm/h in the optimized process condition,the new coating showed high hardness and good corrosion resistance.