Since some spinodal alloys may actually create precipitates upon slow cooling from the solid solution, it may be necessary to quench those metals from the solid solution temperature. The desired atomic shift can then be effected by aging at a lower temperature to allow the crystals to strengthen by atoms of one kind to move to areas of higher concentration without forming a precipitate. Once an alloy has been spinodally strengthened it is free of precipitates that strengthen other alloys. The precipitates that strengthen other alloys form areas where fatigue cracks or other brittle phenomena may occur. The precipitate free spinodal strengthening process accounts for the superior impact strength of a spinodal alloy.
Tin alloys are an excellent choice for sleeve bearings.
Many alloys will perform well under hydrodynamic operation, as the bearing is separated completely from the shaft by a lubricant film. However, when the shaft - bearing system is operating at less than hydrodynamic speeds, under boundary lubricated conditions, a bearing must have certain properties to perform economically and safely. In general, the sleeve bearing must wear while the shaft does not. The best choice for the bearing would be an alloy that wears minimally without damaging the shaft. The spinodal bronzes, as well as aluminum bronze, manganese bronze, beryllium copper and bearing steels do not have the high embedability of the leaded bronze bearing alloys.