Residual Stress and Fatigue Strength of Carburized and Quenched Steel

The fatigue limits of carburized (case depth 0.2 mm through 0.8 mm) and quenched SCr22 (similar to SAE 5120) specimens and their relationship to variations of residual stress distributions for 0.3 mm, 0.6 mm and 0.8 mm case depth SCr22 specimens were determined through the application of three levels of repeated stress: those of equal to, higher than or less than the fatigue limit.

It was shown that if the compressive residual stress in the outer layer of the specimen is sufficiently reserved during repeated stress, residual stress contributes to a higher fatigue limit, although its distribution changes.