薄壁压力容器焊接接头疲劳研究

Investigation on welded joint fatigue of thin-wall pressure container

关键词:  单轴拉伸  双轴拉仲  疲劳

Key words:  uniaxial tension  biaxial tension  fatigue

摘要:

本文采用十字型焊接试板模拟圆筒型压力容器简体部焊缝承受双轴拉伸的力学状态,利用J积分、应变能原理研究这种承受双轴拉伸交变应力作用下焊接接头的疲劳。试验证明:da/dN=C·(△J)^m的表达式适应焊接接头在双轴拉伸交变应力作用下疲劳裂纹的扩展规律,可用于压力容器使用寿命的估计。

Abstract:

This paper deals with the welded joint fatigue of a cylindrical pressure container simulated on a cross-shaped weld test plate with biaxial tension. The investigation was based on the J integral and the principle of strain energy. The experimental results show that the expression da/dN=C(ΔJ)^m coincides with the law of fatigue crack extension of a welded joint under the action of alternating stresses cavsed by a biaxial tension and is applicable to estimate the fatigue life of a pressure container.