The Effect of Material Variables on the Fatigue Life of AISI 52100 Steel Ball Bearings

The effect of material variables on the fatigue life of AISI 52100 steel in ball bearings is examined. An apparently significant negative correlation with the abundance of certain trace alloying elements has been found. An effect of gas content has not been proven. Some difference in the endurance of bearings tempered for various lengths of time at different temperatures is shown. The most effective means available for obtaining improved fatigue life are certain techniques of vacuum melting. An approximate two-fold increase over catalog fatigue life is obtained by single vacuum melting, and a 7.7-fold increase has been achieved in tests using multiple consumable electrode vacuum remelting. This, in conjunction with previously reported evidence for the existence of a lower limit for fatigue life, suggests the possibility of producing bearings with better than 99.5% reliability at catalog life. Contributed by the ASLE Technical Committee on Bearings and Bearing Lubrication and presented at the Annual Meetin...