Friction and wear behavior under oil lubrication conditions of amorphous-nanocrystalline composite coatings deposited via HVAS

Abstract

To prolong the service life of heavy-duty vehicle engine parts subject to wind and sand exposure, a FeCrMoWBRe amorphous-nanocrystalline composite coating was prepared via high-velocity arc spraying for its higher wear resistance than the traditional one. The adhesive strength of the coating is approximately 60.5 MPa, the hardness is approximately 13.3 GPa, and H 3 /E r 2 is 0.07 GPa, indicating that the coating has excellent wear resistance. Under the condition of oil lubrication, the wear rates of the coating under different loads (50–150 N) are in a range of (0.993–250) × 10 −7 mm 3 ·N −1 ·m −1 ; the coating performance is most stable under low and medium loads (50–100 N). It is proved that, abrasive and fatigue wear are the predominant wear mechanisms under low and medium loads (50–100 N), while abrasive, fatigue, and delamination friction as well as wear mechanisms are the dominant under higher loads (e.g., 125 and 150 N) for the coating. After adding abrasive particles, the wear rates of the coating under different loads are in the range of (3.6–259) × 10 −7 mm 3 ·N −1 ·m −1 ; the wear amount is not significantly increased under higher loads (125 and 150 N). The wear mechanism is almost the same under this condition. These results indicate that the coating performs stably under low and medium loads and shows resistance to abrasive particles, especially under higher loads. • A Fe-based amorphous-nanocrystalline alloy composite coating with excellent wear resistance was prepared by HVAS. • The influences of load and the third-body abrasive particles on the wear resistance were investigated. • The results have guiding significance to the wear resistance of heavy-duty vehicle engine parts in high wind-sand area.