基于等效等时应力应变曲线的 金属材料多工况蠕变分析

In order to evaluate the creep deformation of turbine blade under multiple loading cases in the engineering design stage, a method of equivalent isochronous stress-strain curve based on the isochronous stress-strain curve corresponding to the single loading case was proposed. The method was carried out and tested by an aeroengine's long-term trial. The results show that, the average relative error of the residual radial deformation of turbine blade computed by the proposed method is 15.30% with that of the aeroengine's long-term trial, but for the two other commonly used methods, one is the two-dimensional analysis method based on the beam theory and the other is the three-dimensional FE analysis method based on the time step, the corresponding comparison results are 45.35% and 31.14%, respectively, which indicates the good application of the proposed method.