Methodenentwicklung zur Lebensdauerberechnung hinsichtlich thermo-mechanischer Ermüdung (TMF) an motorischen Bauteilen

In this work two approaches for the TMF (thermo-mechanical Fatigue) lifetime prediction were used. Both approaches are based on a nonlinear stress analysis using the elastoplastic material model of CHABOCHE. The lifetime is calculated using two fatigue criteria. The first approach is the fracture mechanics based damage parameter. It assumes that the maximum length of a microcrack represents the damage and TMF lifetime is dominated by microcrack growth. The second damage is model proposed by NEU/SEHITOGLU which describes TMF in terms of mechanical damage, creep damage and oxidation damage. Both approaches show good agreement between experiment and simulation.