Corrosion Fatigue of Type 304 Stainless Steel in H2 SO4 and Boiling NaOH

Abstract Smooth bar specimens of Type 304 stainless steel have been fatigue-tested in 10N H2SO4, at 1.0 Hz, at open circuit and under cathodic and anodic polarization. The endurance limit which disappeared at open circuit was regained under anodic passivation at a cyclic stress below the air value. There was no effect of mean stress on the regained endurance limit. Static load tests permitted evaluation of the accelerative effect of cycling. Comparison of the results in the acid with those in boiling 17.5N NaOH showed that the major differences occurred under anodic passivation during cyclic loading. Passivation was beneficial in the acid but not in the caustic, and seemed related to the difference in the chemical composition and consequent ductility of the anodic films.