Reciprocating sliding wear behavior of talc-filled polypropylene: Effect of talc proportion

Abstract

This study investigates the tribological behavior of talc-filled polypropylene (PP-talc) via reciprocating sliding tests. These tests are realized in dry conditions and at room temperature. The cyclic sliding tests were realized using a spherical steel slider with a speed of 30mm/s under the normal load of 10N and along a distance of 15mm. The maximal number of cycles was 15000. Four proportions of talc were utilized: 0% (neat PP), 5, 10, and 50%. Both friction coefficient (COF) and wear rate (Wr) were determined and discussed as a function of talc proportions and the number of sliding cycles. Furthermore, these findings were discussed regarding the induced damage patterns examined via Scanning Electronic Microscopy (SEM). The findings show that the low talc proportion, less than 10%, leads to lower and stabilized COF with nearly the same value and also to a lower wear rate, Wr, relative to the high talc proportion. The COF evolution during the friction was generally occasioned by the stick-slip phenomenon, which is accentuated by the talc proportion. Nevertheless, noticeable high values of these tribological parameters were obtained when using a high talc proportion of 50%. The SEM analyses of the worn surface after 15000 cycles revealed different damage forms: material displacement, chip formation, rolls, and delamination wear. The formation and displacement of chips within the groove are accentuated by increasing the talc proportion.