Solute friction and forest interaction

Ghiath Monnet (1) , Benoit Devincre (2)

1 EDF R&D MMC - Matériaux et Mécanique des Composants
2 LEM - ONERA - CNRS - Laboratoire d'étude des microstructures [Châtillon]

Solute friction is known to prevail in crystals where a solution of point defects results in a diffuse resistance to dislocation motion. This property is often used to strengthen materials. In this paper we show that it affects also dislocation-dislocation interactions. Dislocation dynamics simulations are used to investigate and quantify this property. The solute friction results in a shielding of elastic interactions leading to a significant decrease of the intrinsic strengths of junction and annihilation reactions. Simulations in static and dynamic conditions show that the interaction stability decreases with the friction stress. A model is proposed to account for the modification of the interaction coefficient predicted by massive simulations in latent hardening conditions. Results suggest that the observed softening is mainly due to the decrease of the line tension of dislocations involved in the dislocation-dislocation interactions.

Mots clés: Physical Sciences

Ghiath Monnet, Benoit Devincre. Solute friction and forest interaction. Philosophical Magazine, 2006, 86 (11), pp.1555-1565. ⟨10.1080/14786430500398425⟩. ⟨hal-00513632⟩