Fatigue calculation for transient proportional and non-proportional multiaxial vibrational stress for component optimisation based on the Modified Mohr-Mises-Hypothesis

Abstract The Modified Mohr-Mises-Hypothesis (MMMH) allows fatigue analysis in a broad scope: notched and unnotched metallic parts made of homogenous ductile or brittle materials, under oscillating, multi-axial and transient proportional or non-proportional loads. It is the result of 30 years of research with multiple publications which validated its core concepts. Its novelty lies in the conservation of relevant signs and inclusion of factors for nonlinearity. Now, a post processing method has been added using Rainflow count for periodic processes. By considering the mean stresses through load cycle-based Haigh diagrams an equivalent stress is calculated. This enables a practical linear fatigue analysis.