Dissipative effects in high and very high cycle fatigue
This work presents a mechanical and energy analysis of metallic materials during high and very high cycle fatigue tests. Energy balances are derived from quantitative imaging techniques. Heat sources are estimated from temperature fields measured by an infrared camera. Kinematic fields are obtained by using digital image correlation techniques and used to compute the deformation energy. A first aim is to analyse the energy relevance of the concepts of fatigue limit and stabilized cyclic behavior. A second aim is to compare dissipation fields at mesoscale with the microstructural distribution of slip bands. Finally, conventional (30-50 Hz) and ultrasonic (20 kHz) fatigue tests are used to analyse the frequency effect on the dissipative behavior of the material.