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Ultrafine-grained (UFG) pure Ti processed by equal-channel angular pressing was subjected to dynamic compression at a stain rate of ∼4000 s−1 over a wide temperature range. It is shown that the structure in longitudinal sections evolves from elongated shapes to polygons in dynamic testing at 93–473 K and to equiaxed grains at 673 K which grow to ∼1.8 μm. The deformation mechanisms of UFG pure Ti are discussed with reference to its crystallographic texture.

In this work we demonstrate that pure compression of the single phase bcc Mg–12 wt.% Li and Mg–20 wt.% Li alloys in a high-pressure torsion system induces the precipitation of hexagonal close-packed (hcp) Mg and hcp Li-rich phases, which remain stable under ambient conditions. This transformation is enhanced with increasing pressure. Shearing under pressure of the multiphase microstructure results in the dissolution of the metastable hcp phases and the subsequent growth of the bcc matrix grains.

Nanocrystallization behavior of Al85Ce8Ni5Co2 amorphous ribbon induced by severe plastic deformation and by linear heating thermal treatment has been compared using differential scanning calorimetry, X-ray diffraction and transmission electron microscopy. Thermal treatment of the as-quenched ribbon results in the joint formation of several crystalline phases, whereas plastic deformation at room temperature induces only primary precipitation of a-Al nanocrystals. This is evidence for the athermal nature of the deformation induced crystallization process.

Orientation imagining microscopy was used to measure the distributions of grain boundary misorientations in ultrafine-grained nickel processed by high-pressure torsion and equal-channel angular pressing. Both procedures give high fractions of high-angle boundaries but also higher fractions of low-angle boundaries than anticipated from a random distribution.

The microhardness and microstructural evolution during high pressure torsion testing in samples of pure nickel were investigated. Results were obtained on Ni samples subjected to annealing prior to high pressure torsion. A detailed TEM and X ray study were used. During torsion, the final microstructure was independent of the grain size. It was demonstrated that the processing parameters of strain and applied pressure were important for microhardness refinement and increased microhardness during high pressure torsion.