Articolo in rivista, 2016, ENG, 10.1103/PhysRevB.94.064101

Glassy features of crystal plasticity

Lehtinen A.; Costantini G.; Alava M.J.; Zapperi S.; Laurson L.

1,3,4,5 : COMP Centre of Excellence, Department of Applied Physics, Aalto University, P.O. Box 11100, Aalto, Espoo, Finland / 2,4 : Center for Complexity and Biosystems, Department of Physics, University of Milano, via Celoria 26, Milan, Italy / 4 : ISI Foundation, Via Alassio 11/C, Torino, Italy / CNR-IENI, Via R. Cozzi 53, Milan, Italy

Crystal plasticity occurs by deformation bursts due to the avalanchelike motion of dislocations. Here we perform extensive numerical simulations of a three-dimensional dislocation dynamics model under quasistatic stress-controlled loading. Our results show that avalanches are power-law distributed and display peculiar stress and sample size dependence: The average avalanche size grows exponentially with the applied stress, and the amount of slip increases with the system size. These results suggest that intermittent deformation processes in crystalline materials exhibit an extended critical-like phase in analogy to glassy systems instead of originating from a nonequilibrium phase transition critical point.

Physical review. B, Condensed matter and materials physics 94 (6)

Keywords

SELF-ORGANIZED CRITICALITY, DISLOCATION AVALANCHES, MICROMETER-SCALE, CRACKLING NOISE, SINGLE-CRYSTALS

CNR authors

Zapperi Stefano, Costantini Giulio

CNR institutes

ICMATE – Istituto di Chimica della Materia Condensata e di Tecnologie per l'Energia, ISC – Istituto dei sistemi complessi