High-cycle fatigue data for solution-treated Type 304 stainless steel were generated under load-controlled conditions and compared with available strain-controlled, low-cycle information from the literature. Although there are significant differences between the two procedures with respect to the initial stress-strain history, it is shown that a good correlation may be obtained if stress-tostrain and strain-to-stress conversions are made with the aid of cyclic stress-strain curves. Using this technique, fatigue curves were obtained between 72-1100 F for failures in the range of 10 -10 cycles. Carbide precipitation, either during test or during pretest thermal aging, will result in an increase in fatigue strength when compared to the solution-annealed state, but the magnitude of the strength increase is likely to be reduced upon continued aging. Several tests run at an ultrasonic frequency (20,000 Hz) gave questionable results because of rapid temperature increases induced by internal friction and, also, because of the probability of very localized deformation within the sample.
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