Tribo-behaviour of APS and HVOF sprayed WC–Cr₃C₂–Ni coatings for gears

Abstract

The tungsten-carbide coatings could be employed to minimise failures of gears due to excessive wear in hostile operating atmospheres. In this work, WC-Cr 3 C 2 -Ni powder was deposited on the SS 316L substrate using APS and HVOF processes. The deposited coatings were characterised and investigated for the effects of dissimilar counter bodies. The unidirectional sliding experiments were conducted on the ball-on-disc tribometer (ASTM G99-95a). The variable contact pressure was applied to simulate the tangible effect of contact stress variation during the dry sliding in the gears. The wear mechanisms depicted that the wear is in the mild regime and better durability of both coatings. The results of tribo-testing and analysis of results by ANOVA confirmed that contact pressure and hardness of counter body are significant factors influencing friction and wear. Furthermore, the relation between contact surface temperature and adhesion of debris to the surface has been studied.

Microstructure and Tribo-Behavior of WC–Cr3C2–Ni Coatings by Laser Cladding and HVAF Sprayed: A Comparative Assessment

“…From the above research, it was known that WC–Cr3C2–Ni is one of the most important commercially powder to prepare high-wear resistant coatings for steel substrate [ 14 , 15 , 16 ]. Herein Cr 3 C 2 was strengthening phase and metal Ni worked as binding phase.…”

Wear and corrosion behaviour of the cryogenically treated tungsten carbide coatings

“…However, the recent thermal spraying processes such as high-velocity oxygen fuel (HVOF) and air fuel (HVAF) have successfully overcome the limitations of the plasma spray process by minimizing the porosity and the decarburization of the coatings as they work at lower flame temperatures and higher particle velocity [3][4][5]. In the automotive and aerospace industries, WC-Co coatings have been extensively employed to develop wear-resisting surfaces as a substitute for chromium-based hard coatings [6][7][8]. The WC-Co coatings are mostly utilized where wear resistance is essential, but still, can be considered for severe corrosion resistance applications [9].…”

Performance of thermal-sprayed WC-Cr3C2-Ni coatings in slurry erosion for hydrodynamic turbines

“…Tungsten carbide-based coatings are mostly preferred in aggressive environments to increase wear resistance and improve erosion resistance [11][12][13][14][23][24][25][26][27][28][29]. Further, the corrosion resistance of WC-based coating increases with the addition of chromium to the matrix [22,30].…”