AZ91D镁合金化学复合镀Ni-P-ZrO_2的工艺与性能  

Processes and properties of electroless Ni-P-ZrO_2 composite coating on AZ91D magnesium alloy

作　　者：宋影伟[1] 单大勇[1] 陈荣石[1] 韩恩厚[1] 

机构地区：[1]中国科学院金属研究所材料环境腐蚀试验研究中心,沈阳110015

出　　处：《中国有色金属学报》2006年第4期625-630,共6页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(50574086)

摘　　要：对镁合金传统化学镀工艺进行了改进,避免了使用氢氟酸和六价铬等有毒物质。采用化学镀与化学复合镀相结合方法,在AZ91D镁合金上获得了Ni-P-ZrO2纳米化学复合镀层,并研究了新工艺化学镀前处理和镍沉积机理及复合镀层的结构和性能。结果表明:新工艺方法获得的Ni-P镀层更均匀、致密,耐蚀性优于传统工艺化学镀层;Ni-P-ZrO2复合镀层与AZ91D合金基体在3.5%NaCl溶液中的动电位极化曲线对比表明,该复合镀层对镁合金可以起到明显的保护作用;从磨损实验结果可见,Ni-P镀层的磨损质量损失率几乎为Ni-P-ZrO2镀层的3倍,说明ZrO2纳米粉的加入能改善镀层的耐磨性。Traditional process of electroless Ni-P plating on AZ91D magnesium alloy was improved, and the poisonous substances of hydrofluoric acid and Cr^6＋ were not used. The mechanism of pretreatment and nickel initial deposition for new process was investigated. Meantime, the process of Ni-P-ZrO2 composite plating was developed, and the microstructure and properties of the composite coating were studied. The results show that the Ni-P coating prepared with new process is more compact and uniform, and the corrosion resistance is superior to that of traditional process Ni-P coating. The potentiodynamic polarization curves in 3.5 % NaCl solution indicate that the Ni-P-ZrO2 composite coating could provide adequate protection to magnesium alloy substrate. The wear mass loss of Ni-P coating is nearly twice more than that of Ni-P-ZrO2 coating, implying that the wear resistance of the composite coating is improved due to the co-deposition of ZrO2 nanometer particles.

关 键 词：A291D镁合金 Ni—P-ZrO2镀层 化学复合镀 耐蚀性 耐磨性 

分 类 号：TG174.4[金属学及工艺—金属表面处理]