FATIGUE LIFE OF ALUMINIUM ALLOY 2017(A) UNDER PROPORTIONAL CONSTANT AMPLITUDE BENDING WITH TORSION IN ENERGY APPROACH

摘要

From the fatigue test results obtained for duralumin 2017(A) under constant-amplitude pure torsion, pure bending and two combinations of bending with torsion, tau_a= 0.5sigma_a, tau_a=sigma_a, we can draw the following conclusions. The value of parameter k occurring in the criterion is constant for the considered material and it does not depend on the life level. The criterion of normal and shear strain energy density parameter in the critical plane, applied for determination of the fatigue life of the material similar to 2017(A) alloy allows to obtain the results similar to the experimental ones, included in the scatter band with the coefficient 3 as for pure bending. The critical plane is determined with the maximum parameter of shear strain energy density.