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Content available remote Professor Jan Czochralski - distinguished scientist and inventor
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EN
Prof. J. Czochralski was born in Kcynia in Central Poland in 1885 and died 50 years ago in Poznan. In 1904 he moved to Berlin where he attended university courses in chemistry. He obtaining an engineering degree started to work as assistant to famous scholar Wichard von Mocllcndorf. Right from the beginning of his career he took interest in what can be now described as physical metallurgy. He pioneered research in plastic deformation of single crystals and contributed to crystallography. In 1929 he received an honorary degree from Warsaw University of Technology (WUT) and a year later accepted professorship position with the Faculty of Chemistry. Soon after he organized Department and later Institute of Metallurgy and Metal Science. His major interest continued to be with processing of metals and in particular he researched crystallization. Research in this field resulted in invention of the famous Czochralski method for growing large single crystals, which paved the way to modern technologies of electronic materials. He also studied elastic, plastic properties of metals and their corrosion resistance. Professor J. Czochralski was also a pioneer in what is now described as technology transfer. His inventions match excellence of scientific achievements. Obtained a number of patents in Germany and Poland. Professor J. Czochralski lived in turbulent times. Holding two citizenships, Polish and German, and acting successfully both within business and acadcmia he made a great number of fans and enemies. Before the World War II, he was involved in much publicized legal disputes with a staff member from WUT. During the war he continued with research in the unit approved by the German administration. This has been judged unfair by a group of professors who made him to retrieve from the University live. He continued with his inventions in Kcynia, his birthplace. The scientific foundations build at WUT by Czochralski proved to be resistant to historical misfortunes. Faculty of Materials Science and Technology, the leading materials research institution in Poland, is proudly continuing tradition of metallurgy and metal science at WUT. This Faculty is also one of the leaders in technology transfer taking fully with the reach achievements of its famous founder.
PL
Profesor Jan Czochralski jest numerem trzy na liście najwybitniejszych polskich uczonych. Co prawda nie ma osiągnięć tego samego kalibru, jak Mikołaj Kopernik czy Maria Skłodowska-Curie, ale na pewno zasługuje na to, żeby znaleźć się na stałe w szkolnych podręcznikach. Śmiało można go nazwać "ojcem nowoczesnej elektroniki". Metoda otrzymywania monokryształów, wynaleziona przez Jana Czochralskiego, wykorzystywana jest dzisiaj na całym świecie.
EN
In this semianalytic study, a question has been raised, and then answered, as to what extent Jan Czochralski, a renown Polish chemist, crystallographer and metallurgist, or even material (viz metal) scientist, etc., should belong, in terms of his achievements, to (physicochemical) metallurgy or ought to be recognized rather as a chemist, working with metals and their “doped derivatives”. The bare ground for answering the question consists of the fact that he did his research quite unseparably within physicochemical and/or mechanochemical (as a specific important subject) metallurgy of quite complex as well as very practical systems that he was able to address thoroughly by his investigations.
EN
The paper summarizes briefly the current status of research in the field of nanocrystallization of metallic glasses especially highlighting the influence of glass composition and conditions of devitrification process on size, morphology and composition of crystallization products. Conventional crystallization creates a nanocrystalline structure only in glasses with particular compositions. Any metallic glass ,decomposing in a primary crystallization process, can be converted into partially nanocrystalline material using non-conventional methods of heat treatment, e.g. high-temperature or low-temperature nanocrystallization. Temperature of devitrification process influences sizes and compositions of crystallization products for any volume fraction of crystalline phase. The change of crystallites sizes can change their morphologies. The change of a crystallite composition usually affects the lattice parameter but also can result in a change of crystallographic structure of the same phase or in formation of another phase. Composition of primary crystallites is dependent on temperature as well as on time of devitrification process. The lower the annealing temperature and the shorter the annealing time (smaller crystallites) the more the crystallites composition differs from the equilibrium state.
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