637-0132/02 – Metallurgy of Pure Metals (MČK)

Student will gain the following abilities: - understand necessity and significance of pure materials for development of new disciplines, such as microelectronics, optoelectronics … - classify manners of division and refining of materials, stages of purification and principles at production of highly pure materials. - describe basic characteristics of ion exchange, chromatography, sorption, extraction, distillation, rectification, transport reactions, electrodialysis, electrolysis, transfer of electricity. - understand significance of effective distribution coefficients at separation of substances and relationships with thermodynamics of phase balance. - use the theoretical knowledge of crystallisation methods of directional crystallisation and zonal melting, including CZ method at refining of substances and preparation of crystals. - analyse conditions at the phase interface solidus- liquidus and their influence on effective distribution coefficient, mass transfer, kinetics of growth of crystallic materials, concentration undercooling, convection and growth defects. - acquire and overview about techniques and equipment suitable for refining of specific materials - determine values of equilibrium and effective distribution coefficients from binary and ternary diagrams, thermodynamic equations and from experiment - select the suitable technology for obtaining of thin layers using epitaxial technology and diffusion processes

In new perspective areas of science and technology, as e.g. technology of semiconductors, microelectronics, optoelectronics, technology of superconductive materials, vacuum technology, nuclear metallurgy, space metallurgy and technology, materials, metals and their special alloys and compounds of a high chemical purity with defined physical and structural parameters and specific utility properties are required. The subject "Fundamentals of Metallurgy of Pure Metals" deals with methods of refining and preparation of high purity substances and the stress is laid not only on a high degree of chemical purity attainable by means of chemical and/or hydrometallurgical physicochemical methods, e.g. sorption, extraction, crystallization from aqueous solutions, electrolysis, but also by means of pyrometallurgical methods, such as crystallization from melts, evaporation, condensation and transport reactions, electrotransport, diffusion separation of substances, removing of gases from melts as well as refining of metals in vacuum. When preparing high purity metals by means of crystallization refining methods, zone melting and directional crystallization, which are principal methods of preparation of defined high purity metals, even in the single crystal form, a controlled redistribution of admixtures and impurities present in the basic substance occurs on the melt-crystal phase interface.

Hein, K., Buhrig, E. Barthel, J. Kuchař, L.: Kristallisation aus Schmelzen, VGI Leipzig 1983, 344 s. Kristallizacija iz rasplavov, Metallurgia Moskva, 1987. Vignorovich, V.N., Volpjan, A.J., Kurdujumov, G.M.: Napravlennaja kristallizacija I fizikochimičeskij analiz. Chimija Moskva, 1986, 200 s. Hadamovsky, H.F.: Werkstoffe der Halbleitertechnik. VEB Deutscher Verlag für Grundstoffindustrie, Leipzig, 1986, 386 s.

2 control tests