A regime beyond the Hall–Petch and inverse-Hall–Petch regimes in ultrafine-grained solids

Ultrafine-Grained Metals

Ultrafine-grained (UFG) metallic materials are at the cutting edge of modern materials science as they exhibit outstanding properties which make them very interesting for prospective structural or functional engineering applications. Due to the progress in severe plastic deformation techniques during the last decade, ultrafine-grained microstructures are no longer only restricted to easy to def...

Special Grain Boundaries in Ultrafine-Grained Tungsten

Field ion microscopy and computer simulation were used for the study of an atomic structure high-angle grain boundary in hard-drawn ultrafine-grained tungsten wire. These boundaries with special misorientations are beyond the scope of the coincident site lattice model. It was demonstrated that the special non-coincident grain boundaries are the plane-matching boundaries, and rigid-body displace...

Macroeconomic Regimes and Regime Shifts

Evolution of texture in an ultrafine and nano grained magnesium alloy

The evolution of texture was discussed during the formation of ultra-fine and nano grains in a magnesium alloy severely deformed through accumulative back extrusion (ABE). The microstructure and texture obtained after applying multiple deformation passes at temperatures of 100 and 250°C were characterized. The results showed that after single ABE pass at 100°C an ultrafine/nano grained microstr...

Microstructure of Ultrafine- Grained Metals after Ecap

This paper was aimed at verification of functionality of the ECAP technology at extrusion of the copper, alluminium alloys and steel. Experiments were made on equipment, which is demonstrated in the Fig 1. Deformation forces were measured during extrusion, resistance to deformation was calculated and deformation speed was determined approximately. Analysis of structure was made with use of ligh...