High cycle fatigue life of metals

Abstract

In eight different materials with U.T.S. ranging from 5 to 80 kpmm −2 the fatigue life curves were determined both for cycling with constant stress amplitude and for cycling with constant plastic strain amplitude in the high cycle region (number of cycles to fracture > 10 5). The results made it possible (1) to check directly the validity of the Manson - Coffin law in the high cycle region; (2) to show how far the different fatigue life curves can be mutually transformed via the cyclic stress - strain curve; (3) to determine the threshold values of the plastic strain amplitude corresponding to the endurance limit.