Estudo do deslizamento de aço inoxidável austenítico contra compósito de PTFE e carga de rejeito de scheelita

Abstract

Contact pressure and sliding speed are parameters that have an influence over the coefficient of friction and the temperature during the contact between PTFE composites and a metallic counter-face. The reduction of coefficient of friction combined with the increase of temperature occurs when both parameters are increased. This study focuses on identifying how different conditions of contact pressure and sliding speed influence the tribological behavior of a PTFE based composite. The evaluated materials were pure PTFE and PTFE reinforced with 10% and 20% of tailings of scheelite. It was used tribological test with a pin-on-disc configuration, with an austenitic stainless-steel pin in contact (plane-plane) with the specimens. Overall, the results revealed a decrease in the coefficient of friction with the increase of contact pressure and sliding speed, for either pure PTFE and the composites. The condition where the pressure and speed were higher, there was a significant increase of temperature between the tribological pair. Also, composites with 10% and 20% of tailings of scheelite, reduced between two and three, and one and two of orders magnitude, respectively, the wear rate compared to pure PTFE under all conditions tested.