Abstract: The low cycle fatigue tests for 316L stainless steels were conducted at test temperatures of 293 K and 873 K respectively under different strain ranges. The amplitude correlation and temperature correlation of material cyclic properties were discussed. Non-Masing characteristics were compared under different conditions and the low cycle fatigue life was predicted by using energy method. The testing results show that at the initial of the cycle under various conditions, different degrees of cyclic hardening phenomena may occur, and then cyclic softening and saturation may occur until the materials fail. Compared with the testing condition of 873 K, the non-Masing characteristics of the material at 293 K is more significant. The non-Masing characteristics at two temperatures are more obvious under large strain range. When using the energy method to predict fatigue life, the predicted results are all located in the twofold scatter band, and the results considering non-Masing characteristics are more accurate than those of considering Masing characteristics. Under the temperature of 873 K and large strain range, the significant dynamic strain aging effect leads to subtle difference between the predicted results considering the non-Masing and Masing characteristics.

Key words: 316L stainless steel, non-Masing characteristic, fatigue life prediction, dynamic strain aging

摘要： 对316L不锈钢在不同应变范围下分别进行了293 K和873 K试验温度下的低周疲劳试验，讨论了材料循环特性的幅值相关性和温度相关性，比较了不同条件下non-Masing特性，并利用能量方法进行了低周疲劳寿命预测。实验结果表明, 在不同条件下，循环初期会出现不同程度的循环硬化现象，随后会出现循环软化、饱和直至材料失效；与873 K 试验条件相比，材料在293 K温度下的non-Masing特性更为显著；在大应变范围下，两温度下材料的non-Masing特性更加明显。采用能量方法进行疲劳寿命预测时，预测结果均位于两倍分散带内，且基于non-Masing特性得到了比基于Masing特性更为精确的预测结果。在873 K温度和大应变范围下，显著的动态应变时效效应导致考虑non-Masing与Masing特性的预测结果相差不大。

关键词: 316L不锈钢, non-Masing特性, 疲劳寿命预测, 动态应变时效