A Theory of the Non-Linear Influence of Normal Stress on Fatigue under Combined Stresses

摘要

In previous papers it has been suggested that fatigue results from alternating shearing stress, and that the resistance of material to this action is influenced by the normal stress acting on the critical shear plane. In an earlier paper the influence of the normal stress was considered to be linear. The present paper investigates the possibility that the influence of the normal stress may be non-linear. The possible effect of anisotropy is also considered.nA non-linear theory is developed and compared with other theories and with results of tests of SAE 4340 steel at a hardness of Rockwell C-25.