Design guidelines for PM parts subject to dry rolling–sliding wear

Abstract

This work improves the systematic approach proposed in previous papers, aimed at defining design criteria specific for powder metallurgy (PM) parts subject to wear in application. Dry rolling–sliding tests have been performed on PM steels obtained under different process conditions, and the results have been used as a knowledge base in the proposed design procedure to evaluate the effect of the material variables (porosity and microhardness) and geometrical parameters (contact length) on wear resistance. The failure criterion considered here to ensure the functionality provides to compare the wear thickness with a value deriving from the dimensional tolerances. If the failure criterion is not matched, then a change in the material variables and/or geometrical parameters is proposed. The occurrence of plastic deformation and/or brittle contact at the surface region is also considered. Examples of application show that the most significant improvement is obtained by modifying both material variables and geometrical parameters.

Keywords:

• Wear
• Design criteria for PM

The authors are grateful to Dr W. Pahl (GKN Sintermetals) for providing the specimens.