Combined Effects of Penetrated Graphite and Dispersed Sulfide on the Tribological Properties of Bronze

Abstract

The present study describes the tribological properties of penetrated graphite bronze containing dispersed sulfide under dry conditions. The graphite was penetrated using a shot peening and roller burnishing to the friction surface only. Shot peening was applied to obtain a micro-dimples for penetrate the graphite. The tribological properties were evaluated using a face-to-face-type testing apparatus under dry conditions. The counter specimen was three chromium alloy steel balls with a flat surface. The disc specimens were prepared for sulfide bronze and bronze, respectively casting material and sintering material. The results showed that the friction properties improved by penetrated graphite. In particular, sintering sulfide bronze did not occurred seizure at high load. The contact surface of bronze without sulfide observed not only disc-component but also the ball-component by EPMA analysis. Furthermore, it was inferred that the friction properties was improved when sulfide and graphite were each other different area on friction surface by EPMA analysis. Combined effects of sulfide and graphite on the tribological properties of the bronze under dry sliding conditions were confirmed.