Open AccessМеханизм упрочнения ультрамелкозернистого алюминия после отжига
Author(s) -
М.Ю. Гуткин,
Т.А. Латынина,
Т.С. Орлова,
Н.В. Скиба
Publication year - 2019
Publication title -
fizika tverdogo tela
Language(s) - English
Resource type - Journals
eISSN - 1726-7498
pISSN - 0367-3294
DOI - 10.21883/ftt.2019.10.48257.481
Subject(s) - materials science , grain boundary , condensed matter physics , dislocation creep , annealing (glass) , grain boundary strengthening , hardening (computing) , dislocation , climb , torsion (gastropod) , grain boundary sliding , plasticity , lattice (music) , flow stress , severe plastic deformation , deformation mechanism , crystallography , composite material , grain size , thermodynamics , alloy , microstructure , physics , chemistry , medicine , surgery , layer (electronics) , acoustics
A theoretical model is proposed that describes the mechanism of hardening of ultrafine-grained aluminum, obtained by severe plastic torsion deformation, after low-temperature annealing. In the framework of the model, hardening is realized due to the sequential transformation of the grain-boundary dislocation structure. In particular, plastic deformation occurs through the emission of lattice dislocations from triple junctions of grain boundaries containing pile-ups of grain-boundary dislocations, the subsequent sliding of lattice dislocations in the bulk of the grain, and the formation of walls of grain-boundary dislocations climbing along opposite grain boundaries. The energy characteristics and critical stresses for the emission of lattice dislocations are calculated. The theoretical dependences of the flow stress on the plastic deformation are plotted, which show good qualitative and quantitative agreement with experimental data.