Study on Fatigue Life Prediction of TC4-DT Structural Simulants by Using Critical Distance Theory  

作　　者：Taiyu Piao Xiaoan Hu Taiyu Piao;Xiaoan Hu(College of Aircraft Power Engineering, Nanchang Hangkong University, Nanchang, China)

机构地区：[1]College of Aircraft Power Engineering, Nanchang Hangkong University, Nanchang, China

出　　处：《World Journal of Engineering and Technology》2024年第2期320-338,共19页世界工程和技术（英文）

摘　　要：In the actual engineering of the structure, mechanical notch is inevitable, which will significantly reduce the fatigue life of the structure. In order to ensure the application of notch structures in engineering, the accurate evaluation of the impact of notch on fatigue life has become the basis of fatigue reliability design of structures. To investigate the influence of the concave structure on the overall fatigue life in practical engineering, three different sizes of V-notch parts and concave structure simulation parts were designed, and the life prediction was carried out by using the critical distance method. The results show that the stress gradient of the concave structure with the same stress concentration coefficient is much greater than that of the V-notch structure. Considering the notch effect, the S-T model in the critical distance method is modified by the stress concentration coefficient and stress gradient, and it is found that the life prediction accuracy reaches the ideal.In the actual engineering of the structure, mechanical notch is inevitable, which will significantly reduce the fatigue life of the structure. In order to ensure the application of notch structures in engineering, the accurate evaluation of the impact of notch on fatigue life has become the basis of fatigue reliability design of structures. To investigate the influence of the concave structure on the overall fatigue life in practical engineering, three different sizes of V-notch parts and concave structure simulation parts were designed, and the life prediction was carried out by using the critical distance method. The results show that the stress gradient of the concave structure with the same stress concentration coefficient is much greater than that of the V-notch structure. Considering the notch effect, the S-T model in the critical distance method is modified by the stress concentration coefficient and stress gradient, and it is found that the life prediction accuracy reaches the ideal.

关 键 词：Notched Fatigue Critical Distance Stress Concentration Stress Gradient 

分 类 号：TG1[金属学及工艺—金属学]