Direct measurement of local constitutive relations, at the micrometre scale, in bulk metallic alloys

E Plancher (1) , V Favier (2) , C Maurice (1) , E Bosso (3) , N Rupin (3) , Julien Stodolna (3) , D Loisnard (3) , J.-B Marijon (2) , J Petit (4) , J.-S Micha (5) , O Robach (6) , Olivier Castelnau (2)

1 LGF-ENSMSE - Laboratoire Georges Friedel
2 PIMM - Laboratoire Procédés et Ingénierie en Mécanique et Matériaux
3 EDF R&D MMC - Matériaux et Mécanique des Composants
4 LEME - Laboratoire Energétique Mécanique Electromagnétisme
5 STEP - Synthèse, Structure et Propriétés de Matériaux Fonctionnels
6 NRS - Nanostructures et Rayonnement Synchrotron

Multiscale models involving crystal plasticity are essential to predict the elastoplastic behavior of structural materials with respect to their microstructure. However, those models are often limited by a poor knowledge of the local constitutive behavior. This article reports a method to measure the mechanical behavior directly, at the micrometre scale, in bulk crystalline materials. Local strain and stress states were evaluated at the surface of a bent stainless steel crystal by combining total strain measurements – performed with the digital image correlation technique on optical images – with elastic strain measurements obtained by Laue microdiffraction. A local constitutive relation was measured, in an efficient nondestructive way, without the need for full-field simulations. The method was validated by a comparison between the measured local behavior and the macroscopic behavior of the single crystal.

Mots clés: digital image correlation.; strain; X-ray Laue microdiffraction; stress; local constitutive behavior

Domaines: Matériaux; Mécanique [physics.med-ph]

E Plancher, V Favier, C Maurice, E Bosso, N Rupin, et al.. Direct measurement of local constitutive relations, at the micrometre scale, in bulk metallic alloys. Journal of Applied Crystallography, 2017, 50 (3), pp.940-948. ⟨10.1107/S1600576717006185⟩. ⟨hal-01663617⟩