Investigation of notch fatigue dispersion considering stress gradient
Aiming at the problem that the microstructure and size of notch parts lead to large differences in fatigue dispersion,to accurate-ly predict the fatigue dispersion of notch parts,taking notch parts with rectangular section as an example,the finite element submodel method combining macroscopic Chaboche cyclic plastic constitutive model and microscopic crystal cyclic plastic constitutive model was a-dopted,and considering the notch effect,the statistical standard deviation of stress gradient influence factor,equivalent stress and longitu-dinal strain as variables was proposed as the fatigue indicator parameter FIPnotch.The fatigue dispersion of fatigue indicator paramter FIPnotch was compared and analyzed with the classical Fatemi-Socie fatigue indicator parameters FIPFS with different displacement loads,displacement load ratios and notch diameters.The results show that the notch fatigue dispersion can be well predicted by fatigue indicator parameter FIPnotch with different displacement load amplitudes,displacement load ratios and notch diameters and the accuracy and applica-bility are higher than that of the classical FIPFS method.
万方数据
维普
