文献类型：期刊文献

英文题名：Investigation of non-classical creep behaviors in a Fe-Cr-Ni alloy at 540°C-600 °C: Microstructural origins and effects

作者：Liu, Xiewen[1];Lv, Dian[1];Zhu, Wujun[1];Zhao, Peng[1];Xiang, Yanxun[1];Xuan, Fu-Zhen[1]

机构：[1]East China Univ Sci & Technol, Sch Mech & Power Engn, Shanghai Key Lab Intelligent Sensing & Detect Tech, Shanghai 200237, Peoples R China

年份：2026

卷号：222

期号：P1

外文期刊名：INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING

收录：;EI(收录号：20261620502357);WOS:【SCI-EXPANDED(收录号:WOS:001716794300001)】；

基金：This research was funded by the National Key Research and Devel-opment Program of China (Grant No. 2022YFF0605600) , the National Natural Science Foundation of China (Grant Nos. 12327807, 12004114) , and the Basic Research Program of Shanghai Science and Technology Innovation Action Plan (Grant No. 24TS1412200) .

语种：英文

外文关键词：Fe-Cr-Ni alloy; 'Non-classical' creep behavior; Mechanical properties; Microstructure; Life evaluation

摘要：This study focuses on the creep behavior of a Fe-Cr-Ni alloy and its associated effects within the temperature range of 540 degrees C-600 degrees C. A 'non-classical' creep behavior was observed and its microstructural origins were investigated via interrupted creep tests. Its creep rate goes through three main stages: a stage of sharp decrease, which is mainly due to the dynamic recovery and sub-grain formation; a stage of rapid increase, which is due to the coarsening of fine intragranular M23C6 phase; and an extended stage of relative stability, which is associated with the balance between the formation and coarsening of M23C6 phases. The influence of creep damage on mechanical properties revealed that after different creep exposures, tensile strength, yield strength and hardness increased and then remained relatively stable. This process is initially dominated by the fine grains and subgrains, and later by the development of fine M23C6 phase and grain growth. Interestingly, the coarsening of fine M23C6 phase within grains degrades the creep resistance, while enhancing the mechanical properties within the 2.5%-20% creep life range. The anomalous creep behavior can complicate life assessment, as the stressexponent analysis and microstructural evidence both indicate that the steady-state creep rate cannot be equated to the minimum rate. To address this, we propose a method for reliably determining the true steady-state creep rate under such non-classical creep conditions.