This paper was produced for the 2019 NAFEMS World Congress in Quebec Canada

Resource Abstract

Fatigue failure is a two-stage process combining crack initiation and growth to failure. Traditional simulation methods concentrate only on one stage or the other. This leads to inaccurate predictions where both stages are significant. Typical examples include welded structures, lightweight jointed structures and cast components.



Total-Life is a methodology that unifies crack initiation and growth. It is based on the principles of strain-life (EN) and fracture mechanics and incorporates a state-of-the-art multiaxial crack-tip plasticity model to account for R ratio and overload retardation effects. A thorough introduction to the new methodology is presented in this paper.



A finite element-based (FE) approach has been developed using the Total-Life methodology. This method has been demonstrated on a complicated weld. Simulation results were found to correlate exceptionally well with physical tests to within a factor of 2. The approach offers numerous benefits over traditional weld fatigue analysis techniques. The advantages are discussed.