Evaluation of tribological properties of nuclear-grade steel

The evolution of friction and wear of nuclear-grade P91 steel is studied at constant load and sliding velocity. The objective of the present investigation was to establish the changes in wear damage and wear scar morphology resulting from sliding of a spherical steel ball. These studies were performed by keeping sliding distance as a variable. Adhesive failure at lower sliding distance to fatigue-induced fretting wear of oxide layer was observed with increasing sliding distance. This is attributed to the formation of a Fe3O4 (magnetite) tribo-oxide layer on the surface. Deformation, spallation, and phase composition of this tribo-oxide layer were found to be the principal mechanisms that influenced the tribological properties of steel