Abstract
In the paper we show that grain boundary sliding dominates in the creep of A999 aluminum polycrystals and is accommodated by rotation modes of intragranular deformation. Accommodation mechanisms strongly depend on the applied stress σ and creep temperature T. At low σ and T, accommodation occurs by dislocation glide and mesoscale fragmentation. At high σ and T, there appears lattice curvature, which causes the development of shear bands, multiscale fragmentation, and formation of a quasi-neck with nanosized subgrains and plastic microrotations. Noncrystallographic shears in their subboundaries propagate in local lattice curvature zones under τmax by the plastic distortion mechanism.
Original language | English |
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Pages (from-to) | 276-284 |
Number of pages | 9 |
Journal | Materials Science and Engineering A |
Volume | 733 |
DOIs | |
Publication status | Published - 22 Aug 2018 |
Keywords
- Creep
- Fracture
- Grain boundary sliding
- Grains and interfaces
- High-purity aluminum polycrystals
- Plasticity methods
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering