高温低周疲劳寿命预测模型

系统评介了应变变程划分（ＳＲＰ），频率划分（ＦＳ），频率修正损伤参数（ＦＭＤＦ），损伤速率（ＤＲ）和应变能划分（ＳＥＰ）等五种在国内外影响较大的高温低周疲劳（ＨＬＦ）寿命预测模型，并对ＨＬＦ寿命预测的损伤力学方法作了简介。基于能量原理，本文建立了一个新的ＨＬＦ寿命预测模型，即时间修正能量（ＴＭＥ）模型。通过引入时间因子和采用优化处理技术，该模型能较准确地反映塑变、蠕变和环境介质等ＨＬＦ损伤机制的作用。利用镍基超合金Ｒｅｎｅ’９５（涡轮盘材料）的ＨＬＦ试验数据，对上述几个模型的拟合能力和预测能力进行了评价。结果表明，对于该材料，ＴＭＥ模型要优于其他几个模型。

High Temperature Low Cycle Fatigue Life Prediction Models

Reviews five prominent high temperature low cycle fatigue (HLF)life prediction models,namely,SRP model,FS model, FMDF model,DR and SEP model, and gives a summarized account of the approach of continuum damage mechanics to the HLF life prediction. Based on the energy principle,a new HLF life prediction model, i.e.,the TimeModified-Energy Model,is put forward. Through using time as the modifying term and introducing the optimization processingteTME model can indicate the effects of the frequency and the different time-dependent damaging mechanism on the material under high temperature.The models mentioned above are evaluated for their ability to predict the HLF life of a nickel-base superalloy Rene'95eused in turbine disks.It is found that the predictability of TME model is better than that of the others.