【摘要】 P91钢是火力发电机组中高温部件的重要材料,研究其蠕变性能对高温部件的寿命评估有重要意义。研究了P91钢在实验温度为620℃,试验应力分别为145,155和164 MPa下的蠕变曲线,基于损伤力学的方法建立了Kachanov-Rabotnov蠕变本构模型。通过对Norton方程、Kachanov-Rabotnov蠕变本构模型与实验数据比较得出:两者预测的P91钢断裂寿命与实验数据相差不大,最大误差小于7%;Kachanov-Rabotnov本构模型蠕变曲线要优于Norton方程得到的蠕变曲线,并且Norton方程所得到的蠕变曲线要比试验曲线偏低,预测的蠕变过于保守。更多还原

【Abstract】 P91 steel is an important material for high temperature components in thermal power generators. The creep curves of P91 steel on the experimental temperature of 620 ° C and the test stresses of 145,155 and 164 MPa were studied. The Kachanov-Rabotnov creep constitutive model was established based on the damage mechanics method. By comparing Norton equation and Kachanov-Rabotnov creep constitutive model with experimental data,the predicted fracture life of P91 steel by the two approaches is not much different from the experimental data,and the maximum error is less than 7%. The Kachanov-Rabotnov constitutive model creep curve is superior to the creep curve obtained by the Norton equation,and the creep curve obtained by the Norton equation is lower than the creep curve from experimental data,and the predicted creep is too conservative.更多还原