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为了提高铝合金材料的表面性能,使其具有较高的硬度和耐磨性,利用激光熔覆技术在6063铝合金表面制备了添加稀土氧化物CeO2的Ni60合金熔覆层。分析了激光熔覆CeO2+Ni60熔覆层的宏观形貌、显微组织及硬度,研究了其摩擦磨损性能,并与未添加稀土的Ni60合金熔覆层和铝合金基体进行了对比研究。结果表明,加入2%CeO2可降低Ni60熔覆层表面起伏,获得较好的熔覆层宏观形貌,同时有效地减少Ni60熔覆层中的裂纹、孔洞和夹杂物,促进晶粒细化,提高熔覆层的组织均匀性;添加2%CeO2的Ni60熔覆层比未加稀土的Ni60熔覆层组织更加均匀,晶粒较细小,气孔等组织缺陷更少,熔覆质量较好;在相同深度位置的显微硬度,2%CeO2+Ni60熔覆层明显高于Ni60熔覆层,2%CeO2+Ni60熔覆层最高硬度可达HV0.051180,是6063铝合金基体平均硬度的8.4倍;在相同磨粒磨损条件下,2%CeO2+Ni60熔覆层试样的耐磨性是铝合金基体的7.1倍,是Ni60熔覆层试样的1.6倍;激光熔覆Ni60可以显著降低铝合金表面摩擦系数,而添加稀土元素Ce能提高Ni60熔覆层的摩擦系数稳定性,从而改善耐磨性能。
In order to improve the surface properties of aluminum alloy and make it have high hardness and wear resistance, Ni60 alloy cladding with rare earth oxide CeO2 was prepared by laser cladding on 6063 aluminum alloy. The macroscopic morphology, microstructure and hardness of laser cladded CeO2 + Ni60 coatings were analyzed. The tribological properties of the coatings were also studied. The results show that the Ni60 alloy cladding and the aluminum alloy matrix are comparatively studied. The results show that the addition of 2% CeO2 can reduce the surface roughness of Ni60 cladding layer and obtain better macro-morphology of the cladding layer, meanwhile effectively reduce the cracks, holes and inclusions in the Ni60 cladding layer and promote the grain refinement, Improve the microstructure uniformity of the cladding layer. The Ni60 cladding layer with 2% CeO2 is more uniform than the non-rare earth Ni60 cladding layer, the grains are finer and the pores and other microstructure defects are less and the cladding quality is better. The microhardness of the same depth position, 2% CeO2 + Ni60 cladding layer was significantly higher than the Ni60 cladding layer, 2% CeO2 + Ni60 cladding layer up to HV0.051180, is 6063 aluminum alloy matrix average hardness of 8.4 times The wear resistance of 2% CeO2 + Ni60 cladding layer is 7.1 times that of aluminum alloy substrate and 1.6 times that of Ni60 cladding layer under the same abrasive wear condition. Laser cladding Ni60 can significantly reduce the wear resistance of aluminum Alloy surface friction coefficient, and the addition of rare earth Ce can improve the Ni60 coating friction coefficient stability, thereby improving the wear resistance.