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3D Discrete Dislocation Dynamics Investigations of Fatigue Crack Initiation and Propagation

Auteurs: 

C. Déprés (SYMME)
C. Robertson (SRMA, CEA )
M. Fivel (SIMaP, CNRS)

Both nucleation and propagation of fatigue cracks in fcc metals are investigated, using 3D discrete dislocation dynamics (DDD) simulations. Firstly, DDD simulations explain the mechanisms leading to the formation of persistent slip bands in surface grains loaded in fatigue. Extrusions are evidenced where the bands intercept the free surface. The extrusion growth rate is estimated for different material parameters and loading conditions.

Introduction to Life Prediction Methodologies for Materials and Structures

Auteurs: 

Serge Kruch (ONERA)
Esteban Busso (ONERA)

In his book "Citadelle" Antoine de Saint Exupéry wrote "Intelligence examines the material while the mind only sees the ship". Such a quote sets the context of this issue of ONERA’s Aerospace Lab Journal entitled "Life prediction Methodologies for Materials and Structures" very well.