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Tribological Properties and Wear Mechanisms of Polyurethane Sealing Material Over a Wide Temperature Range

Abstract The service environment has an important influence on the friction and wear properties of elastomeric seals. This study is devoted to investigating the tribological properties of polyurethane against 316L stainless steel under a wide temperature range of –50 °C to +60 °C. The significant characteristics such as coefficient of friction (COF), wear rate, and worn surface morphologies of samples were examined and compared. The results indicated that the different temperatures exhibited significantly diverse tendencies on the evolution characteristics of COF, including the fluctuation and stability. The COF took longer to establish equilibrium at low temperatures, and the A-COF after stability was the lowest at 60 °C. Compared with cold environment, high temperatures (i.e., 60 °C) accelerated the wear of polyurethane. Moreover, polyurethane worn surfaces presented different damage morphologies with changes in temperature. Three different mechanisms of wear, including abrasive wear, fatigue wear, and roll formation, gradually changed with increasing temperature. This study provides insights into the wear mechanism associated with temperature and is useful for designing and selecting proper operating conditions for prolonged applications of the sealing material under extreme circumstances.