Abstract

The results of experiments on Society of Automotive Engineers (SAE) 1043 steel show that the cyclic stress-strain response in small regions of a notched specimen is not necessarily the same as that obtained in tests on smooth specimens of the same metal. At the roots of notches (two different notch radii were used) plastic flow occurs at the same cyclic lives as in unnotched specimens, when the longitudinal total strains are similar. Cyclic plasticity develops in many fewer cycles near the notches than in smooth specimens under the same longitudinal total strains. The more sharply notched specimens soften more rapidly at locations near the notches than the less severely notched ones under identical longitudinal strains.

Issue Section:
Research Papers
Keywords:
fatigue (materials), softening steels, plastic properties, plastic deformation, stress strain diagrams, stress concentration, cyclic loads, geometric effects

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