Wear Behavior of Plasma Sprayed Ni-WC Composite Coatings
Seal materials often lose their effectiveness due to the wear of surface under the combined effect of environment and load. In this research, a metallurgical bonding composite coating reinforced with nickel -coated tungsten carbide (Ni -WC) particles was produced on 40Cr carbon steel substrate by plasma sprayed. The bond strength of the coating/substrate interface and the tensile strength of the coating itself reached 260–330 and 100–132MPa, respectively. Effects of Ni and WC contents on the wear behavior of the coating have been systematically investigated at two different wear conditions, namely the high stress pin-on-disk abrasion and three-body abrasive wear. The results show that the higher the Ni content in the coating, the lower the hardness and wear resistance. In stress pin-on-disk abrasive wear, the mass percent of Ni in the coating having the lowest wear amount was 40%, and which was 60% in three-body abrasion. In view of the above, the WC reinforcement of the composite coating plays an important role in protecting the matrix from being worn-out, whereas in the abrasive wear, the wear mechanism is mainly controlled by the scratching and micro-cutting of the matrix followed by the pull out of WC particles due to the scratching action of abrasives. The wear resistance of the 40Cr carbon steel composite coating (Ni -WC) is better than that of the flame overlaid coating.
Wei Pan and Jianghong Gong
C. G. Bao, Y. M. Gao, J. D. Xing, G. S. Zhang, "Wear Behavior of Plasma Sprayed Ni-WC Composite Coatings", Key Engineering Materials, Vols. 336-338, pp. 1731-1733, 2007