The influences of the overlay on the seizure resistance of the crosshead-pin bearing for large size diesel engines were evaluated by using a dynamic load bearing apparatus. The running-in property was also evaluated by measuring the electrical resistance of the oil film. The major results are: (1) The seizure resistance of the aluminum-tin bearing plated with the tin-copper overlay using the tin bonding layer is much higher than that of the conventional lead-based overlay plated white metal and aluminum-tin bearings; (2) Increasing the copper content in the tin-copper overlay is effective in improving the seizure resistance. If the copper content becomes too high, however, the running-in property is degraded, thereby causing the seizure resistance to decrease; and (3) Increasing the overlay thickness is advantageous for improving the running-in property, and thereby raising the seizure resistance. If the overlay becomes too thick, however, seizure occurs within the overlay, thereby causing the seizure resistance to decrease.
