作　　者： ; ;

机构地区： 南京航空航天大学能源与动力学院

出　　处： 《机械工程学报》 2007年第2期219-224,共6页

摘　　要： 借鉴HALFORD和SALTSMAN发展总应变-应变范围区分法(TS-SRP)的经验,基于应变能区分法(SEP)建立总应变-应变能区分法(TS-SEP)。类似于TS-SRP,TS-SEP同时反应了材料失效行为和流动行为两个方面的特征。通过材料循环流动行为的经验方程,建立弹性应变范围一寿命方程,然后与由SEP确定的非弹性应变范围-寿命方程相加,获得循环总应变范围与疲劳寿命之间的关系。寿命预测时,TS-SEP不需要区分非弹性应变分量,因此特别适应于非弹性变形较小的高强度、低延性材料,扩大了SEP的应用范围。通过Rene95和AF2-1DA两种镍基高温合金蠕变疲劳试验数据的初步验证,结果表明:TS-SEP比SEP具有更可靠的预测结果,对Rene95材料基本试验的预测精度有97．5％在2倍因子范围内,对AF2-1DA材料基本试验的预测结果全在2倍因子范围之内。对验证性试验,TS-SEP在四种方法(TS-SEP,TS-SRP,SEP和SRP)中具有最高的预测精度。 A total strain version of strain energy partitioning （TS-SEP） is formulated based on strain energy partitioning（SEP）, utilizing the method of HALFORD and SALTSMAN for developing TS-SRP. Like TS-SRP, TS-SEP characterizes the behavior of alloys in two aspects： Failure behavior and flow behavior. Elastic strainrange-life relations are established by using the empirical equations of flow behavior of alloys. Total strainrange-life relations are given by summing elastic strainrange-life relations and inelastic strainrange-life relations. TS-SEP can be used for creep-fatigue life prediction without partitioning the inelastic strainrange, so it is applicable in the low-strain, long-life regime where SEP is difficult to use. Then, TS-SEP is evaluated and verified by using two advanced nickel-base superalloys, Rene95 at 650 ℃ and AF2-1DA at 760 ℃. The results indicate that TS-SEP can predict the creep-fatigue life of Rene95 at 650 ℃ and AF2-1DA at 760 ℃ more reliable than SEP. The agreement of the predictions with the observed lives of the baseline tests is quite good for TS-SEP, with 97.5% percent of the Rene95 baseline data being predicted to within factors of two, and 100% of AF2-1DA, and the scatter band of TS-SEP for verification tests is lower than all other three methods （SEP, TS-SRP, SRP）.

关 键 词： 应变能区分法 应变范围区分法 高温低周疲劳 蠕变疲劳 寿命预测

领　　域： [理学] [理学]