2020 Volume 60 Issue 6 Pages 1358-1365
The effect of lattice defects on the tribological behavior under tricresyl phosphate (TCP) added poly-α-olefin (PAO) lubrication was investigated in the nanostructured steels produced by heavy plastic deformation processes. In surface-nanostructured SUJ2-bearing steel, tribological behavior with high friction coefficient was observed in ball-on-disk tests when compared to non-deformed steel. In addition, a similar phenomenon was observed in ultra-low carbon (ULC) steel with a high density of lattice defects (grain boundary, dislocation and so on). By increasing the density of lattice defects, a higher friction coefficient was observed. The reason for the tribological behavior with high friction coefficient seems to be that the compound film of Fe–O–P system formed in the ball-on-disk test was worn down.