【摘要】 以作者开发的焊趾半椭圆表面裂纹应力强度因子数据库SIFSC及基本模式法为基础,给出了复杂应力场中焊趾表面裂纹在疲劳扩展过程中形态变化规律及寿命的工程分析方法,并用这个方法计算了一些典型焊接接头在一些典型外加应力场和残余应力场中的裂纹形态发展曲线(CADC).只有按裂纹扩展的自然途径,即按CADC来计算,才能得出正确的疲劳寿命估算.残余应力及角接接头中支板的存在对疲劳寿命有不可忽略的影响.更多还原

【Abstract】 Based on a database of stress intensity factors of surface Cracks (SIFSC) derived by the authors and the elementary mode method, an engineering procedure for estimating crack growth behavior and fatigue life of semi-elliptical surface cracks at weld toes are presented in this paper. Some examples of crack aspect development cureves are given for typical cracked weld joints sub-jectsd to external loading and residual stress conditions. The correct predicted fatigue lifes can only be obtained if the path of integral is along the crack aspect development curve. Residual stress and the existence of a brace plate have appreciable effects on fatigue lifes.更多还原