Tittle: Fatigue damage analyzed and predicted by means of three-dimensional DD simulations
Speaker: Christian Robertson, French Atomic Energy Commission
Date：October 26 at 14:00
Location：200 Lecture hall, Shanghai Univerisy
Speaker Introduction
Christian Robertson is senior researcher of French Atomic Energy Commision (CEA), HdR in Materials Physics, Habilitation à diriger des recherches of University Paris-Saclay. His research activities focus on the observation and corresponding physical modelling of plasticity mechanisms in structural nuclear materials, at the grain scale (µm). The following applicative cases have been described in various publications, including: Fatigue lifetime prediction under complex loading conditions; Prediction of dose-dependent fracture toughness evolutions in ferritic materials; Prediction of stress corrosion cracking initiation in post-irradiated austenitic stainless steels; Prediction of thermal and irradiation creep lifetime in heavily damaged metallic materials.
Abstract
Current fatigue design methods shortfalls include:
Supporting material data is not always relevant or available, especially with respect to in-service conditions affecting quasi-structural components.
Multiaxial and mean stress loading conditions are usually poorly understood.
Actual components have variable surface finish, resulting in the application of overly conservative safety factors for fatigue design.
Several case studies are addressed in the context of fusion reactor design, using sub-grain three-dimensional dislocation dynamics simulations. The cases presented include fatigue crack initiation and propagation mechanisms, applicable to structural metallic materials.
