ToughMet® Alloy: Improving Thrust Bearing Performance Through Enhanced Material Properties

We present standardized test results indicating that ToughMet^® copper-nickel-tin alloy will outlast traditional transmission thrust bearing materials without increasing frictional power loss or endangering mating components. Sleeve bearing tests show the PV (bearing pressure × linear speed) limit of ToughMet is more than three times that of leaded tin bronze. In thrust washer wear rate testing ToughMet provided 4 and 14 times reduction in wear rate as compared to leaded tin bronze at speeds and pressures found in transmissions. The performance advantage is related to differences in physical and mechanical properties between the two materials.