在超临界流体条件下制备了纳米Al2O3/镍基复合电铸层, 采用显微硬度仪和扫描电镜分析了复合电铸层的微观结构和显微硬度。结果表明: 在超临界流体条件下进行电铸, 可有效解决Al2O3纳米颗粒在镀液中的团聚问题, 并促进其在电铸层中均匀弥散分布; 随Al2O3添加量的增多, 电铸层的显微硬度先升后降; 在超临界流体压力为14 MPa、镀液中Al2O3添加量为60 g·L-1时, 电铸层的显微硬度最大, 为1 142.2 HV, 此时电铸层中Al2O3的质量分数为9.88%。

Ni-based composite electroforming layer with nano-Al2O3 pairticles was prepared under the condition of supercritical fluid, and microstructure and microhardness were analysed by micro hardness tester and scanning electron microscopy. The results show that aggregation problem of nano-Al2O3 particles was resolved effectively by electroforming under the condition of supercritical fluid, and electroforming made nano-Al2O3 particles distribute in electroforming layer evenly. The microhardness of electroforming layer increased and then decreased with the increase of adding amounts of Al2O3 particles. Microhardness of the electroforming layer up to maximum (1 142.2 HV) and mass fraction of Al2O3 in electroforming layer was 9.88wt% when pressure of the supercritical fluid was 14 MPa and adding amount of Al2O3 particles in plating solution was 60 g·L-1.