Dislocation avalanches from strain-controlled loading: A discrete dislocation dynamics study

نویسندگان

چکیده

We study strain-controlled plastic deformation of crystalline solids via two-dimensional discrete dislocation dynamics simulations. To this end, we characterize the average stress-strain curves as well statistical properties strain bursts and related stress drops a function imposed rate stiffness specimen-machine system. The system exhibits strain-rate sensitivity such that larger results in higher at given strain. In limit small driving spring stiffness, sizes durations avalanches are power law distributed up to cutoff scale, exhibit temporally asymmetric shapes. discuss dependence on parameters compare our those from previous simulations where quasistatic stress-controlled loading was used.

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ژورنال

عنوان ژورنال: Physical review

سال: 2021

ISSN: ['0556-2813', '1538-4497', '1089-490X']

DOI: https://doi.org/10.1103/physreve.104.025008