The elastoplastic behavior of yield stress fluids

Élie Merveille N'Gouamba (1) , Julie Goyon (1) , Philippe Coussot (1)

1 navier umr 8205 - Laboratoire Navier

By means of the incremental elastic modulus for small deformations superimposed on creep and subsequent recovery tests, we follow the structural state of various soft-jammed systems (yield stress fluids) in their solid regime. We demonstrate that the solid state of the material is associated with a persistent elastic network of constant elastic modulus up to yielding (solid-liquid transition), while progressively more additional elastoplastic elements are involved. The main features of these elastoplastic elements, i.e. increase of both the plastic and the elastic deformation components with the square of the shear stress, reveal the fundamental characteristics of a simple generic model (independent of material structure) describing the different components of the mechanical behavior of such systems in their solid regime.

Mots clés: Elastic deformation; Jamming; Plastic deformation; Rheological properties

Domaines: Mécanique des fluides [physics.class-ph]

Élie Merveille N'Gouamba, Julie Goyon, Philippe Coussot. The elastoplastic behavior of yield stress fluids. Physical Review Fluids, 2019, 4 (12), ⟨10.1103/PhysRevFluids.4.123301⟩. ⟨hal-02912572⟩