prof. Ing. Pavel Lejček, DrSc.
The research of the group Materials with Controlled Microstructure is focused on preparation, characterization and theory of a wide spectrum of structural metallic materials – from single crystals via oriented bi- and tricrystals up to materials with micro- and/or nanocrystalline structure. Establishment of basic properties of individual, fully defined grain boundaries and triple junctions and their anisotropy enables understanding the collective behavior of the grains, their boundaries and junctions in multicrystalline structures.
Oriented single crystals, bi- and tricrystals are grown from melt using the floating-zone melting and Bridgman techniques. Micro- and nanocrystalline structures are prepared by specific thermomechanical treatment in solid state. Besides full crystallographic characterization of the grain boundaries and triple junctions in bi- and tricrystals we study their chemical composition (solute segregation), mobility (migration) and/or mechanical and fracture behaviour. In multicrystalline materials we are interested in texture formation and in the grain development and morphology during plastic deformation and annealing. An important part of our research represents theoretical modeling of the dislocation behavior and/or grain boundary segregation.