21/4Cr-1Mo鋼の純クリープ・疲労相互作用の有効応力概念に基づく評価の試み
1989 年 55 巻 514 号 p. 1264-1268
詳細
1989 年 55 巻 514 号 p. 1264-1268
The pure creep-fatigue bebavior of 2 1/4 Cr-1Mo steel at 550°C was analyzed by a damage model which was originally developed by the authors for an evaluation of the pure creep-fatigue behavior of 304 Steel at 650°C. The model consists of two damage parameters, that is, the time-independent damage parameter DI and the time-dependent damage parameter DD. The applicability of the model to 2 1/4 Cr-1Mo Steel was checked and the model was modified as follows. a) DI was modified so that it could describe the effect of mean stress. b) DD was determined as a time integration of the internal stress instead of the overstress It was shown that the above modifications made possible a more reasonable evaluation of the pure creep-fatigue behavior of 2 l/4 Cr-1Mo steel at the temperature.
