Microstructure and wear resistanced of deposited rare earth CeO₂+Ni60 alloys coatings on 6061 Al alloys by laser cladding

To improve the surface properties of aluminum alloy, Ni60 alloy cladding layer containing rare earth CeO₂ were prepared on the surface of 6061 aluminum alloy by laser cladding. The effects of rare earth CeO₂ on the microstructure, microhardness and tribological properties of Ni60 alloys coatings were investigated by means of metalloscope, SEM, micro-hardness test, friction and wear test machine. The results show that the cracks, holes and inclusion in the coatings are reduced with the addition of 2% CeO₂, the grain becomes thin, the microstructure uniformity is improved, and the hardness and wear resistance of the coatings increases. Under the same abrasive wear conditions, the wear resistance of CeO₂+Ni60 cladding layer is 7.1 times as that of untreated aluminum alloy, and 1.6 times of Ni60 cladding layer. Ni60 cladding layer can significantly reduce the friction coefficient of aluminum alloy, and the CeO₂+Ni60 cladding layer can improve the stability of friction coefficient and thus improve wear resistance. The stability of friction coefficient can be improved with the addition of CeO₂, thereby the wear resistance of CeO₂+Ni60 cladding layer can be improved.