热交变载荷下10%Cr耐热钢蠕变疲劳裂纹萌生特征

Creep Fatigue Crack Initiation Behavior of10%Cr Heat Resistant Steel Under Thermomechanical Loading

为调节新能源间歇式发电模式所带来的弊端,需要使用火力发电厂调峰稳定电网波动。调峰过程中机组频繁启停,加剧高温部件的疲劳蠕变损伤。通过分析现有寿命模型描述温度交变载荷下汽轮机转子钢性能的不足,提出预载荷实验方案。且以预载荷实验数据为基础,优化现有寿命预测模型。通过模拟交变温度下的临近工况实验,对比应力应变关系和疲劳蠕变寿命,对所优化的寿命模型进行了评估。

To adjust the oscillation of renewable energy sources in the discontinuous generation of electricity,power plants will be used to stabilize the fluctuations.Fatigue creep damage on power plant components will be increased,during the frequent start-up and shut-down processes of the units.A pre-loading experiment plan was introduced through the analysis on the insufficient stress-strain behavior of gas turbine rotor under thermomechanical loading described by an existed lifetime estimation model.Based on the data of the pre-loading experiments,the current life prediction model was optimized.By comparison of the simulated stress-strain behavior and estimated fatigue creep life near working condition test at alternating temperatures,the optimized life prediction model was evaluated.