基于Ω方法的T/P91耐热钢蠕变持久寿命预测

Creep Rupture Life Prediction of T/P91 Heat-resistant Steels Based on Ω Method

利用Ω方法预测原始态和服役态T/P91耐热钢的蠕变持久寿命,并将其与利用等温线法和Larson-Miller参数法得到的结果进行对比。提出一种基于Ω方法的加速试验方案,该方法仅需一根试样即可快速预测给定温度和应力参数下的蠕变持久寿命。结果表明:与等温线法和Larson-Miller参数法相比,加速Ω方法的预测精度更高;对于服役态T/P91耐热钢,不同蠕变加速试验参数下得到的Ω较接近,蠕变断裂时间预测值均与试验值较吻合。

The creep rupture life of T/P91 heat-resistant steels respectively in original and service state was predicted by Ω method, and the results were compared with those obtained by isotherm method and Larson-Miller parameter method. Meanwhile, an accelerated test scheme was proposed based on Ω method, which could rapidly predict the creep rupture life with only one specimen under given temperatures and stress parameters. Results show that compared with isotherm method and Larson-Miller parameter method, the accelerated Ω method shows higher prediction accuracy. For service state T/P91 heat-resistant steels, nearly same Ω values shall be obtained in different acceleration schemes, and the predicted values of creep fracture time would be in good agreement with actual measurements.