加载速率对汽轮机转子钢低周疲劳损伤的影响  

Effect of Loading Rate on Low-cycle Fatigue Damage of Turbine Rotor Steel

作　　者：何建军[1] 陈荐[1] 孙清民[1] 邱玮[1] 周鹏展[1] 

机构地区：[1]能源高效清洁利用湖南省高校重点实验室(长沙理工大学),湖南省长沙市410076

出　　处：《中国电机工程学报》2011年第2期62-66,共5页Proceedings of the CSEE

基　　金：国家自然科学基金项目(50775015);湖南省教育厅重点科研项目(06A002);湖南省重点学科青年创新基金项目(dl0903)~~

摘　　要：加载速率反映了汽轮机转子启停及运行时温度变化速度与负荷变化速率。对火电厂汽轮机转子30Cr1Mo1V钢在538℃温度下的低周疲劳损伤进行试验研究,研究加载速率对实际低周疲劳损伤和预测低周疲劳损伤的影响。结果表明:在相同的寿命分数下,加载应变速率越大,低周疲劳损伤越小;在同一加载速率下,总应变幅越大对应的低周疲劳损伤也越大;在同等应变幅条件下,转子钢高温低周疲劳预测损伤比实际损伤大,加载速率较低时,转子钢高温低周疲劳预测损伤比较大;加载速率对材料损伤有显著影响的取值范围为0.1%-s-1≤ε≤0.2%-s-1。Loading rate is associated with high thermo-mechanical loads change rate of the turbine rotors during start-up and shut-down procedures.Low-cycle fatigue damage of power plant turbine rotor 30Cr1Mo1V steel was studied at 538 ℃,and the effect on the actual low-cycle fatigue damage and the predicted low-cycle fatigue damage of the loading rate were also studied.The results show that higher strain loading rate leads to the smaller low-cycle fatigue damage in the same cycle life fraction.The greater total strain amplitude brings the greater low-cycle fatigue damage in the same loading rate.While in the same strain amplitude condition,the predicted low-cycle fatigue damage of the rotor steel is larger than the actual one,the low-cycle fatigue predicted damage is greater in the lower loading rate test process.The loading rate range which has significant effect to the material damage is 0.1%×s-1 ￡ e ￡ 0.2%×s-1.

关 键 词：低周疲劳损伤 寿命 汽轮机转子 加载速率 30Cr1Mo1V钢 

分 类 号：TH140[一般工业技术—材料科学与工程]