Abstract:
Ni60A alloy coating containing 20wt% WC was cladded on the inner surface of 45 steel sand blasting nozzle by vacuum high-frequency induction cladding technique, and then the sand blasting nozzle was reamed by lathe and electric discharge shaped machine, respectively. The microstructure and hardness distribution of the coating and substrate were analyzed, and the friction and wear properties of the coating were studied. The results show that the coating had an excellent cladding quality. The coating was smooth and crack-free with a small number of holes. The coating was metallurgical bonding with substrate. After reaming by electric discharge shaped machine, the porosity of the outer layer of the coating decreased and structure was finer compared with that after reaming by lathe. The hardness of the coating was much higher than that of substrate, and the hardness of the outer layer of the coating after reaming by electric discharge shaped machine was higher than that after reaming by lathe. After erosion wear testing for 150 min, the wear loss of the sand blasting nozzle with coating was 11% of that without coating, the friction coefficients of the sand blasting nozzle with and without coating were 0.16 and 0.22, respectively, indicating significantly improved the wear resistance of the sand blasting nozzle cladding with coating.