Statistical inference of 2D random stress fields obtained from polycrystalline aggregate calculations

Bruno Sudret (1, 2) , Hung Xuan Dang (3) , Marc Berveiller (4) , Asmahana Zeghadi (4)

1 GdR MASCOT-NUM - Méthodes d'Analyse Stochastique des Codes et Traitements Numériques
2 msa - Matériaux et Structures Architecturés
3 LAMI - Laboratoire de Mécanique et Ingénieries
4 EDF R&D - EDF R&D

The spatial variability of stress fields resulting from polycrystalline aggregate calculations involving random grain geometry and crystal orientations is investigated. A periodogram-based method is proposed to identify the properties of homogeneous Gaussian random fields (power spectral density and related covariance structure). Based on a set of finite element polycrystalline aggregate calculations the properties of the maximal principal stress field are identified. Two cases are considered, using either a fixed or random grain geometry. The stability of the method w.r.t the number of samples and the load level (up to 3.5 \% macroscopic deformation) is investigated.

Keywords: Polycrystalline aggregates; Crystal plasticity; Random fields; Spatial variability; Correlation structure

Domains: Materials; Mechanics of materials [physics.class-ph]; Mechanics of materials [physics.class-ph]

Bruno Sudret, Hung Xuan Dang, Marc Berveiller, Asmahana Zeghadi. Statistical inference of 2D random stress fields obtained from polycrystalline aggregate calculations. International Journal of Fracture, 2012, pp.1-30. ⟨hal-00660409⟩