用双缺口板试件估算锅炉汽包疲劳裂纹形成寿命的研究

本文提出了用双缺口板试件在常温下的疚劳裂纹形成寿命，估算锅炉汽包疲劳裂纹形成寿命的新方法。文中用弹塑性有限元法对缺口试件进行了分析，还用局部应力一应变法对缺口试件的裂纹形成寿命进行了估算，其结果与试验寿命相差在系数为2的范围以内。同时还研究了变幅低周疲劳下缺口试件和锅炉汽包的损伤，并考虑了平均应力的影响。 

A New Method for Estimating the Fatigue Crack Formation Life of Boiler Steam Drum

A new method is introduced for estimating the fatigue crack formation life of boiler steam drum by using fatigue crack formation life of double notch plate specimens under room temperature. The elastic-plastic finite element analysis is made on the notch specimen, and the crack formation life of the specimen is estimated based on the local stress-strain method. The calculated results are in agreement with test results, the coefficient of scatter being two. Besides, the fatigue damage for both the boiler steam drum and the notch specimen under varied amplitude low cycles is investigated with the effect of average stress taken into account.