Physical correlation between abrasive wear performance and scratch resistance in model polyurethane elastomers

Abstract

Wear behaviors of a series of model cast polyurethane elastomers (CPU) under linear reciprocating sliding and fretting conditions were investigated and physically compared with their corresponding scratch behavior. It is found that the sliding wear and scratch damages of the model systems are both governed by abrasive wear mechanism, which involves tensile tear induced cracking along with material removal on the surface. The scratch resistance against tensile tear induced cracking/material removal of the model CPU systems correlates well with their abrasive wear performance, which can then be linked to their material properties, i.e., a higher tensile strength improves abrasive wear resistance. On the other hand, the fretting wear damage of the model systems is found to be dominated by adhesive-fatigue wear mechanism, and thus cannot be correlated with the scratch performance. Temperature rise measurement of the model CPU systems during wear was also performed to further understand the observed wear behaviors. The present study provides fundamental insights into understanding of complex abrasive wear behavior of polymers through their corresponding simpler scratch behavior.