This work investigates plastic deformation heterogeneity at the macroscopic and microscopic scales within metallic alloys. Indeed, reaching a deeper understanding of the origins and consequences of heterogeneity is crucial, given its influence on the overall mechanical performance of the material.

The main originality of the approach is to use crystallographic texture to reveal and predict the development of non-uniform internal stresses and strain fields. This requires employing reliable crystal plasticity (CP) numerical models to relate the rotations of crystal lattices to the plastic deformation.

Three complementary studies are conducted to assess the validity of the approach. In extruded aluminum alloys, we find that the presence of texture gradients leads to the development of non-negligible internal stresses; incorporating initial texture data into CP models enables accurate prediction of both the magnitude and spatial distribution of these stresses during subsequent processing. In roll-bonded aluminum-steel multilaminates, texture analysis provides valuable insights into the macroscopic through-thickness strain distribution arising during successive roll-bonding passes. Finally, using CP based finite element modeling (CPFEM), we investigate how crystalline interfaces influence plastic strain heterogeneity at the grain scale. In this context, a novel CPFEM framework accounting for grain interactions across crystalline interfaces is proposed to better capture the local strain field when using non-conformal FE meshes.

Membres du jury :

• Prof. Laurent Delannay (UCLouvain)(Promoteur)
• Prof. Hadrien Rattez (UCLouvain) (Président)
• Prof. Pascal Jacques (UCLouvain) (Secrétaire)
• Prof. Kim Verbeken (Universiteit Gent) 
• Prof. Bjørn Holmedal (NTNU)
• Prof. João Quinta Da Fonseca (University of Manchester)

Visio conference (Teams) : 

https://teams.microsoft.com/meet/32035715488281?p=qgzvd4skXXPbbW2OyL