Dry-Sliding Wear and Design Criteria for PM Steels

The dry-sliding wear behavior of two high-density, sinter-hardened, powder metallurgy (PM) steels was found to depend on the formation and stability of a protective oxide layer on the contact surface. The presence of soft nickel-rich austenite in a nickel-alloyed steel prevents the formation of the layer and, therefore, the nickel-free steel shows superior wear resistance. A design procedure for parts subject to dry-sliding wear applications is proposed based on the maximum acceptable wear depth. The influence of sliding conditions on wear depth is calculated and the possibility of improving the performance of parts by varying the material characteristics and part geometry is discussed.