Neale Consulting Engineers - Plain Bearing Failure - Thermal Ratcheting of Tin-Rich White Metal

PLAIN BEARING FAILURE

Plain bearing failure index

7.0 Thermal ratcheting of Tin-Rich White Metals and Thermal Fatigue

Thermal ratcheting of Tin-Rich White Metals and Thermal Fatigue - index

7.1 Thermal Ratcheting of Tin-Rich White Metal

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	Roughening of tin-rich white metal on trailing edge of thrust pads caused by thermal cycling
Main Characteristics	Highlighting of tin-rich crystals in tin-rich white metal on the trailing edges of the pads where the temperature is highest.
Cause	Thermal cycling causing differential rotation of the anisotropic tin-rich crystals in the white metal. It occurs at the trailing edges of the pads where thermal changes are greatest.
Note
Possible Confusion with Other Types of Damage
Comment	The effect is produced by differences in optical reflection by differences in rotation of the different crystals. The amount of rotation is small and does not have a significant effect on performance.