EBSD study of superplastically strained Al-Mg-Li alloy

In this study, electron back scatter diffraction (EBSD) was employed to examine the microstructure evolved during superplastic deformation of advanced Al-Mg-Li alloy. In contrast to the widelyaccepted conception of superplasticity, the microstructure was found to be characterized by elongated grains, a notable fraction of low-angle boundaries, and a distinct (though a very weak) crystallographic texture. All these observations suggested a significant activity of intragranular sli

EBSD study of superplasticity: New insight into a well-known phenomenon

Electron backscatter diffraction (EBSD) was applied to investigate the superplastic behavior of a fine-grain Al-Mg-Li alloy. It was found that microstructural changes were noticeably influenced by the occurrence of continuous dynamic recrystallization. This mechanism involved a transverse subdivision of pre-elongated grains which eventually transformed into chains of nearly-equiaxed grain

Superplastic behavior of fine-grained Al-Mg-Li alloy

The superplastic behavior of fine-grained 1420 Al-Mg-Li alloy was investigated using a modern electron microscopy technique based on automatic analysis of electron backscattered diffraction patterns (EBSD analysis

EBSD study of superplastically strained Al-Mg-Li alloy

In this study, electron back scatter diffraction (EBSD) was employed to examine the microstructure evolved during superplastic deformation of advanced Al-Mg-Li alloy. In contrast to the widely-accepted conception of superplasticity, the microstructure was found to be characterized by elongated grains, a notable fraction of low-angle boundaries, and a distinct (though a very weak) crystallographic texture. All these observations suggested a significant activity of intragranular slip

Microstructural evolution during superplastic deformation of Al-Mg-Li alloy : dynamic recrystallization or grain-boundary sliding?

In this work, advanced capabilities of electron backscatter diffraction (EBSD) were applied to evaluate the role played dynamic recrystallization during superplastic deformation of a typical fine-grained material. It was found that the dynamic recrystallization occurred only locally and thus provided only minor contribution to microstructural evolution. Hence, the preservation of the nearly-equiaxed grain morphology, inherent to the superplasticity phenomenon, cannot be attributed to the dynamic recrystallization

Effect of strain on gap discrete breathers at the edge of armchair graphene nanoribbons

Linear and nonlinear vibration modes of strained armchair graphene nanoribbons with free edges are investigated by means of atomistic modeling. It is shown that phonon modes can be divided into two groups, the XY-modes with the displacements of atoms in the nanoribbon plane, and the Z-modes with atomic displacements normal to the nanoribbon plane. Strained nanoribbons possess a sufficiently wide gap in the phonon spectrum of the XY-modes so that a gap discrete breather (DB) can be excited. Large-amplitude DBs exist within the strain range 0.125 < εxx < 0.20. At larger strains an attempt to excite a DB results in breaking of the nanoribbon, while at smaller strains the gap in the phonon spectrum of the XY-modes is either too narrow or absent. DBs can have energy up to 1 eV and the maximal DB energy is larger for smaller strain of the nanoribbon. A possible role of DBs in the fracture of strained graphene nanoribbons at finite temperatures is discussed