Study on the Fretting and sliding composite wear behavior of Ni-Al bronze under seawater lubrication

Controllable pitch propeller blade bearings experience fretting-sliding composite wear in seawater conditions, yet the underlying mechanisms remain unclear. This study investigates the effects of varying Sliding/Fretting ratios and loads on the wear process. Findings reveal that as the Sliding/Fretting ratio decreases, the wear rate decreases while the average friction coefficient increases. Corrosion can promote the formation of cracks on the material surface. As the load increases, additional cracks and exfoliation become evident at the center of the worn surface, while more grooves are observed in the edge region. The increase in load results in an expansion of the contact area and stress concentration zones, leading to a more extensive area and greater depth of damage to the substrate surface.