Friction and Wear Characteristics of Cu-Based P/M Brake Friction Materials with Addition of Fe and C

Abstract

Cu-based powder metallurgy friction materials were prepared by varying of Fe and C (% weight) in the friction components. The samples were compacted under the load of 24 metric tonnes and sintered at a temperature of 950 °C for 45 minutes. The friction and wear characteristics the materials developed were studied using Chase machine. The results show that Fe and C have different friction and wear characteristics. The friction coefficient of Cu-30%Fe-15%C sample maintained to be high and slightly increased after the drum temperature of 350°C and subsequently stable throughout tests. The friction of Cu-20%Fe-10%C stable until the drum temperature of 450°C and then its start to decay slightly until the end of the test. On the hand, the friction of Cu-10%Fe-5%C start to decay after sliding a few minutes at the drum temperature of 230°C. Thus, it could be postulated that the friction coefficient increased with increasing weight percentage of Fe and C in the friction components. However, the volume loss shows that there is no direct correlation with the Fe and C content. The volume loss of Cu-10%Fe-5%C was higher than the two samples which had the lowest hardness. On the hand, the volume loss of the Cu-30%Fe-15%C was slightly higher than Cu20%Fe-10%C as result of higher porosity and lower hardness. Wear mechanisms of abrasion, adhesion and thermal were observed to be operated during sliding process.