公开(公告)号：US20120271566A1

公开(公告)日：2012-10-25

申请号：US13091943

申请日：2011-04-21

申请人： Vinayak Deshmukh ,  Eric M. Johnson

发明人： Vinayak Deshmukh ,  Eric M. Johnson

IPC分类号： G06F19/00

CPC分类号： G01M5/0033 ,  G01N2203/0073 ,  G01N2203/0212 ,  G06F17/5018 ,  G06F2217/76

摘要： A method of determining the fatigue life of a structure includes the steps of: associating a mathematical equation for total strain amplitude with the structure: Δɛ 2 = σ f ′ E  ( 2  N f ) b + ɛ f ′  ( 2  N f ) c , where: Δε/2=strain amplitude, σf′=fatigue strength coefficient associated with a material of the structure, b=fatigue strength exponent of the material, E=cyclic modulus of elasticity of the material, 2Nf=number of cycles, εf′=fatigue ductility coefficient of the material, and c=fatigue ductility exponent of the material; reducing the fatigue strength exponent (b) such that an elastic portion of a total strain amplitude curve associated with the equation has a reduced slope to account for variable amplitude loading for the structure; generating a total strain amplitude curve, based upon the mathematical equation: Δɛ 2 = σ f ′ E  ( 2  N f ) b reduced + ɛ f ′  ( 2  N f ) c , where (breduced) is now the reduced fatigue strength exponent; and determining a fatigue life of the structure, based on the total strain amplitude curve with the reduced fatigue strength exponent.

摘要翻译： 确定结构的疲劳寿命的方法包括以下步骤：将总应变振幅的数学方程与以下结构相关联：＆Dgr;ε2 =＆sgr; f'E（2 N f）b +εf'（2 N f）c，其中：＆Dgr;＆egr / / 2 =应变幅度，＆sgr; f'=与材料相关的疲劳强度系数 结构，b =材料的疲劳强度指数，E =材料的循环弹性模量，2Nf =循环次数，e = f =材料的疲劳延展系数，c =材料的疲劳延性指数; 降低疲劳强度指数（b），使得与等式相关联的总应变幅度曲线的弹性部分具有减小的斜率，以解释该结构的可变幅度负载; 根据数学公式产生总应变幅度曲线：＆Dgr;ε2 =＆sgr; （2 N f）b减少+εf'（2 N f）c，其中（简称）现在是减少的疲劳强度指数; 并且基于具有降低的疲劳强度指数的总应变幅度曲线来确定结构的疲劳寿命。