Non-linear composite voxels for FFT-based explicit modeling of slip bands: application to basal channeling in irradiated Zr alloys

Aldo Marano , Lionel Gélébart (1)

1 SRMA - Service des Recherches Métallurgiques Appliquées

Explicitly modeling slip bands is a promising method to simulate the consequences of intragranular plastic slip localization on the behavior of strongly localizing crystals such as irradiated metals. In this study, we propose a very efficient framework to implement this modeling strategy based on a massively parallel FFT-based solver enhanced with composite voxels to simulate polycrystals with a regular lamellar structure alternating plastic slip bands embedded within larger elastic bands. To this end, generic composite voxel models have been formulated and implemented, allowing to extend the approach to any type of constitutive behavior in the future. In particular, we show that laminate composite voxels are particularly well suited to improve standard FFT-based solvers in this context, and enable to run polycrystalline simulations accurately accounting for slip bands whose width is two orders of magnitude below the grain size. To demonstrate the potential of this approach , we apply it to an idealized material designed to approximate basal channeling in irradiated textured Zr alloys. Varying the width and the spacing of the modeled slip bands, we show that it allows to capture the increase of grain boundary normal stress concentrations or the enhanced Bauschinger effect induced by an increased localization of plastic slip.

Mots clés: Slip localization; Crystal plasticity; FFT methods; Composite Voxels; Irradiated metals

Domaines: Physique [physics]; Mécanique [physics]; Matériaux et structures en mécanique [physics.class-ph]; Mécanique des matériaux [physics.class-ph]

Aldo Marano, Lionel Gélébart. Non-linear composite voxels for FFT-based explicit modeling of slip bands: application to basal channeling in irradiated Zr alloys. 2020. ⟨hal-02484451⟩