摘要
为了预测焊接构件在中温环境下的疲劳裂纹扩展寿命,提出了一组新的疲劳裂纹扩展方程.采用紧凑拉伸(CT) 试样,对2.25Cr1Mo钢在室温和420℃时的疲劳裂纹扩展速率进行了测试研究,通过速率试验值的回归分析,推导了两种温度下疲劳裂纹扩展速率方程,并利用该方程计算了一台加氢反应器接管焊缝部位浅长表面裂纹的疲劳扩展量和表面裂纹临界长度,对扩展后的裂纹进行了安全评估.研究结果表明,420℃时2.25Cr1Mo钢的疲劳裂纹扩展速率高于室温,反应器接管焊缝处的裂纹疲劳扩展不会威胁其使用安全性。该扩展方程的计算结果具有较好的准确性和可靠度,可用于该钢种的裂纹疲劳扩展预测和安全评估.
To predict the fatigue crack growth life of welded equipments at elevated temperature, a group of novel fatigue crack growth equations was proposed. Crack growth rates of 2.25Cr1Mo were measured at room temperature and 420 ℃ by applying compact tension （CT） specimens. Based on the curvilinear regression of crack growth rate values, the fatigue crack growth equations at two temperatures were deduced. Fatigue growth of shallowlong surface crack in nozzle weld of a hydrogenation reactor and the critical length of surface crack were calculated in terms of these equations, and the safety of grown fatigue crack was assessed. The results show that the crack growth rate of 2.25Cr1Mo at 420 ℃ is higher than that at room temperature. Fatigue crack growth in nozzle weld of the reactor does not seriously affect the equipment safety. The calculated value obtained by solving the growth equations has good accuracy and reliability, and the equations can suitably be used for predicting the fatigue crack growth of 2.25Cr1Mo and assessing its safety.
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2005年第9期1455-1460,共6页
Journal of Zhejiang University：Engineering Science
基金
国家"十五"科技攻关资助项目(2001BA803B03-06).
关键词
疲劳
裂纹扩展
安全分析
加氢反应器
接管
fatigue
crack growth
safety evaluation
hydrogenation reactor
nozzle
