【摘要】 为了探究波形膨胀节在高温环境下的裂纹疲劳扩展行为，以高温波形膨胀节为对象，对其开裂损伤失效问题展开研究。首先，引入断裂力学分析和评定技术，在400℃高温条件下，通过拉伸循环位移作用下的疲劳裂纹扩展试验，模拟实际工程中膨胀节的开裂失效过程；其次，在相同条件下开展疲劳裂纹扩展的数值仿真分析。结果表明，仿真与试验得到的循环次数相对误差均在50%以内，远低于2倍的疲劳寿命误差带，验证了仿真模型的可靠性。研究可为高温波形膨胀节工程中的断裂失效分析提供参考。更多还原

【Abstract】 To explore the crack fatigue propagation behavior of bellows expansion joints under high temperature,this paper takes the bellows expansion joints under high temperature as an object to study its crack damage failure.Firstly,the fracture mechanics analysis and evaluation technique was introduced.Under 400 ℃ high temperature,the fatigue crack propagation test under tension cycle displacement was carried out to simulate the crack failure process of expansion joints in engineering practice;Secondly,based on the same condition,the numerical simulation analysis of fatigue crack propagation was carried out.The results show that the relative error of cycle number obtained by simulation and experiment is within 50%,which is far less than 2 times of fatigue life error band.The reliability of simulation model is verified.This study provides an reference for fracture failure analysis of high temperature bellows expansion joints in engineering.更多还原