Including of Ratio of Fatigue Limits from Bending and Torsion for Estimation Fatigue Life under Cyclic Loading

The paper presents the estimation of the fatigue life under multiaxial cyclic loading of selected construction materials: two aluminum alloys PA4 (6068) and PA6 (2017A), alloy steel S355JOWP (in past called 10HNAP) and cast iron GGG 40. Calculations were based on three criteria of multiaxial fatigue, which is based on the concept of critical plane and the coefficients present in the expressions for the equivalent stresses are calculated on the basis of classical fatigue limits.