In situ production of bulk intermetallic-based nanocomposites and nanostructured intermetallics by high-pressure torsion

Micropowder mixtures of Al-50 mol.% Ni were severely deformed by high-pressure torsion and Al ₃Ni ₂/Ni nanocomposites were produced. The hardness increased with straining, as a consequence of nanograin formation and high-strain-induced solid-state reactions, and saturated to a steady-state level, 920 Hv. The reactions were completed and nanostructured AlNi intermetallics were produced by subsequent annealing. The formation of nanostructured intermetallics was feasible in this process at significantly low temperatures because of the rapid diffusion and short diffusion paths resulting from intense shearing.