采用化学镀方法,在NdFeB磁性材料表面施镀Ni-P-W/Al2O3 复合镀层,观察了镀层表面的微观形貌,测定了镀层的相组成,并且对基体与镀层间的结合强度进行了测试。结果表明:形成了胞状交叠的致密Ni-P-W/Al2O3 复合镀层,纳米Al2O3 颗粒弥散分布于Ni-P-W 合金中;Al2O3 颗粒与Ni-P-W 共沉积有利于提高镀层与基体间的结合强度,镀液中Al2O3 的质量浓度为5~10g/L时,基体与镀层间的结合强度最好。

The Ni-P-W/Al2O3 composite coatings were deposited on the NdFeB magnetic materials surface by electroless plating method. The microstructures were observed, and the phases existed in the coatings were also identified. The interfacial bonding strength between Ni-P-W/Al2O3 composite coatings and NdFeB matrix was also tested. The results indicate that its morphology appears closely nodules structure consisted of Ni-P-W/Al2O3, and the Al2O3 particles were dispersed in the Ni-P-W matrix finely. The interfacial bonding strength is prone to be increased while the Al2O3 powders co-deposited with Ni-P-W coatings. And the interfacial bonding strength would reach the highest value when the Al2O3 concentration is in rang of 5 g/L to 10g/L.