Structure and properties of liquid and amorphous state
Short-range atomic order of metallic liquids and glasses
Atomic structure of metallic alloys in the liquid and glassy (amorphous) state is an important factor determining their properties as well as the glass formation itself. Unlike crystalline substances with periodic long-range atomic order, amorphous and liquid alloys are characterized by short to medium range atomic order on the Ångström or nanometer scale depending on the system. Relative simplicity and diffuseness of diffraction patterns of liquid and amorphous materials, their slight differences even for objects with diverse physical nature essentially complicate investigations of the atomic structure.
We investigate the short and medium range atomic order in metallic glasses and liquids using all of different experimental techniques such as high energy synchrotron wide-angle and small-angle X-ray diffraction, neutron wide-angle and small-angle diffraction, and X-ray absorption spectroscopy. For the interpretation of the experimental data and description of the atomic structure Molecular Dynamics and reverse Monte-Carlo modeling methods are applied.
Atomic structure of Cu65Zr35 metallic glass obtained by reverse Monte-Carlo simulation of X-ray diffraction, neutron diffraction and extended X-ray absorption fine structure data
I. Kaban, P. Jóvári, V. Kokotin, O. Shuleshova, B. Beuneu, K. Saksl, N. Mattern, J. Eckert, A.L. Greer, Local atomic arrangements and their topology in Ni-Zr and Cu-Zr glassy and crystalline alloys, Acta Mater 61 (2013) 2509-2520
Interfacial phenomena and wetting behaviour of liquid metals
Interfacial phenomena (wetting, adhesion, adsorption, interfacial reactions) play an important role in various areas of materials engineering such as for example casting of metallic alloys, production multiphase composites, joining of metallic and ceramic components. We investigate surface and interfacial energies, wetting at surfaces and interfaces, density and density difference of coexisting liquid phases in monotectic metallic alloys by experimental tensiometric measurements and thermodynamic modelling. Wetting behaviour, surface adsorption and interfacial reactions of liquid metals on metallic and ceramic substrates are investigated by sessile drop experimental technique and thermodynamic calculations.