CeO_2对Ni/α-Al_2O_3纳米复合镀层微观组织和摩擦学性能的影响

Effect of Rare CeO_2 on Microstructure and Tribological Properties of Ni/α-Al_2O_3 Nano-composite Coatings

采用纳米复合电镀技术,通过向Ni/α-Al2O3纳米复合镀溶液中添加CeO2方法在45#钢上制备了Ni/α-Al2O3-CeO2纳米复合镀层;研究了CeO2对镀层微观组织、显微硬度及摩擦学性能的影响;用分析型扫描电镜、显微硬度计及摩擦磨损试验机对复合镀层组成、微观组织、显微硬度及摩擦学性能进行了分析。结果表明,适量CeO2的加入促进了纳米α-Al2O3的沉积量,使纳米α-Al2O3在镀层中的分布更加均匀,添加过多的CeO2对纳米α-Al2O3分布不利;CeO2添加量为40g/L时,平均显微硬度比未添加CeO2的提高近30%,磨痕宽度减少近40%;CeO2能改善复合镀层的耐磨性能,有效防止镀层片状脱落。

Rare-earth nano-composite coating was prepared on 45# steel surface by nano-composite coating technology through adding different concentrations of CeO2 in the Ni/α—Al2O3 plating solution. The effect of different concentration of CeO2 on the microstructure, microhardness and tribological properties of nano-composite coating was analyzed by scanning electron microscope （SEM） and micro-hardness tester separately. The results show that adding appropriate CeO2 can promote the nano α—Al2O3 deposition volume, improve the uniform distribution of nano α—Al2O3 in the coating. But adding too much CeO2 has adverse influence on the uniform distribution of α—Al2O3 When CeO2 concentration reach 40 g/L, the average microhardness increases by nearly 30% , the width of wear track decreases by almost 40%. Adding CeO2 improves the antiwear properties of nano-composite coating, coating without dopped CeO2 is characterized by servere adhension and scuffing,while the coating dopped CeO2 is dominaed by slightly abrasive wear.