Investigations of Subcritical Crack Propagation under High Cycle Fatigue
Most of the fatigue life in high cycle fatigue (HCF) is expended in growing subcritical defects to a detectable damage size,followed by rapid growth to failure.This is a significant challenge in design as this leads to concerns with respect to the efficacy of planned inspections and routine repair operations.The variability of the damage phenomena in HCF can impact the characterization of the long fatigue life regimes,as the extent and severity of damage depends on the intensity of the operating loads,and on the intrinsic variations in material characteristics at different scales.In this paper we propose a methodology to account for stochastic variability in HCF by using the framework of the Kitagawa-Takahashi diagram,and the El-Haddad formulation as the design curve for subcritical crack propagation in fatigue and in environmentally assisted cracking (EAC).Moment-based reliability,based on first order and second order reliability methods,as well as Monte Carlo simulation is used to handle stochastic variability in applied stress and defect size.The calculation of a probability of defect propagation at each instant of the subcritical growth process is the goal of the developed framework.Preliminarily validation with available data and an application of the framework to stochastic defect growth for block loading is presented.
Attilio Arcari Nagaraja Iyyer Madan Kittur Nam Phan
Technical Data Analysis Inc.,Falls Church,VA,USA Structures Division,Naval Air Systems Command,Patuxent River,MD,USA
国际会议
北京
英文
1-11
2013-06-16（万方平台首次上网日期，不代表论文的发表时间）