Scientific Research

The central question is how extreme mechanical deformation changes the internal structure, and with it the properties, of crystalline metals. The method under investigation is High Pressure Torsion (HPT), a form of severe plastic deformation (SPD) that compresses and twists a disc-shaped sample under pressures of several GPa, producing grain refinement down to the nanometre scale.

The materials studied are L1₂-ordered intermetallics: crystalline compounds such as Ni₃Ge and Ni₃Al whose atoms occupy specific, ordered positions on the crystal lattice. SPD disrupts their long-range order and can unlock improved mechanical behaviour. Characterising that disorder via Transmission Electron Microscopy (TEM) is the core method: dislocation structures, dissociation schemes, and weak-beam imaging of metastable phases.

A second research stream investigates the use of SPD to improve hydrogen storage properties of light-metal systems, primarily MgH₂ and ZK60 magnesium alloy. SPD-induced defects act as diffusion paths and nucleation sites, accelerating absorption/desorption kinetics. This work also covers neutron-holographic experiments requiring preparation of metal-hydrogen systems, and the stabilisation of deformation-induced lattice defects in hydrogenated palladium.