High temperature low cycle fatigue and fatigue crack growth behaviour of the Udimet 720 Li alloy

In this work, performed within a Brite-Euram European project, low cycle fatigue and fatigue crack propagation behaviour of the udimet 720 Li alloy has been evaluated in condition of pure fatigue and in combined condition of creep-fatigue loading. Low cycle fatigue tests on smooth or notched specimens are used to calibrate models for estimating economic life, and for safe-life approaches employed for non-critical components that are not inspected in service. Fatigue crack propagation tests are used to calibrate crack propagation models, used for damage tolerance analysis, and to calculate safe inspection intervals for critical components. (orig.)