High-Cycle Fatigue Behavior of Solution-Annealed and Thermally-Aged Type 304 Stainless Steel

High-cycle, load-controlled fatigue data have been obtained for solution-annealed and thermally-aged Type 304 stainless steel, for temperatures between 22 and 593°C (72-1100°F) at a cycling rate of 40 Hz. Although these data are principally used to assess fatigue failure in components subjected to rapid stress cycling, it has been shown that they may be correlated with available low-cycle data if cyclic stress-strain curves are used for converting the high-cycle stresses to effective strains. Differences in initial stress-strain history and cycling rates for the high- and low-cycle data evaluated are found to be unimportant. For the thermally-aged material there is an initial enhancement of the high-cycle-fatigue strength but, after long aging times, the strength decreases to a value close to that for unaged material. The carbide precipitates formed during aging appear to influence fatigue life through changes they impart in the cyclic work-hardening rates.