摘要
调峰机组频繁调整负荷,汽轮机汽缸紧固螺栓处于疲劳-蠕变交互作用,对紧固螺栓多轴应力下疲劳-蠕变损伤的研究对调峰机组安全运行和维修具有重要意义。该文对镍基合金Nimonic80A进行了550℃下单轴及空心螺栓的疲劳?蠕变断裂实验,应用Chaboche-Nouaihas模型,用有限元软件ABAQUS模拟了空心螺栓的疲劳?蠕变过程。结果表明,与空心螺栓的纯蠕变断裂不同,疲劳?蠕变断裂发生在应力集中的螺纹处,有限元计算结果与实验结果吻合较好。
Loading of peak generator units were changed frequently. The fastening bolts of steam turbine cylinder case were in fatigue-creep interaction. It was important to study fatigue-creep interaction damage of fastening bolts under multiaxial stress. Fatigue-creep rupture experiments of Nimonic 80A uniaxial specimen and hollow bolts at 550℃ were carried out. Fatigue-creep process was simulated by ABAQUS using Chaboche-Nouaihas fatigue creep model. It is indicated that fatigue-creep rupture of hollow bolt is different from simple creep rupture. Hollow bolt rupture of fatigue-creep is taking place at the position of the first screw thread root, where the stress is concentrated. A good coincidence comparing the result experiment with finite element calculation can be observed.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2007年第32期63-66,共4页
Proceedings of the CSEE
