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Information × Registration Number 0210U001663, 0107U000987 , R & D reports Title Development of technology for creating functionally graded thermoelectric materials popup.stage_title Head Anatychuk Lukyan Ivanovych, Registration Date 17-03-2010 Organization Institute of Thermoelectricity, Academy of Sciences of Ukraine and Ministry of Education and Science of Ukraine popup.description2 Report on 201 pages, 114 figures, 44 tables, 88 references. Research object - peculiarities of creating functionally-graded thermoelectric materials. Research subject - technologies of creating functionally-graded materials realizing the possibility of using bulk thermoelectric effects, which makes power conversion process maximum energy efficient. Research purpose - design, development and creation of optimally inhomogeneous materials for efficiency increase of thermoelectric power conversion method. Basic scientific-technical work results. Technologies and technological equipment for functionally-graded materials (FGM) based on Bi-Te alloys by the pressing methods, by extrusion and the Czochralski method have been developed. Basic scientific-technical work results. Computer methods for determination of optimal distributions of kinetic coefficients of thermoelectric materials whereby maximum thermodynamic efficiency of power conversion is achieved have been elaborated. Optimal inhomogeneity distributions for Вi-Te based material have been determined and requirements to technological conditions of functionally-graded material manufacturing have been established. Directions for improvement of technique for manufacturing extruded thermoelectric materials have been proposed with a view to obtain higher thermoelectric figure of merit and better mechanical stability. Peculiarities of influence of technological pressing conditions (temperature regime; pressure value, its direction, delivery rate; size and composition of the source components) on the possibilities of control over properties of thermoelectric materials have been established. Functionally graded materials has been developed and investigated that confirm the possibility of their production with functional dependences that approach to theoretical ones. The possibility of samples production has been confirmed experimentally. On thermocouple elements with FGM it is achieved ?Тmax improvements by 4K that enables to produce thermoelectric modules with quality that exceeds known native and foreign analogues. Pressing operation technologies of modules legs with FGM is promising since it provides non-waste production. However for its implementation it is necessary to conduct additional investigations for the purpose of condition creation under which the anisotropic powder necessary orientation is achieved. For all that thermoelectric materials figure of merit is increased by 15-20 % and is improved to the level of extruded and single crystal FGM. Technology of FGM development by the Czochralski method enables to obtain materials of the more improved functional dependence in contrast to pressing and extrusion where continuous functional dependences are approximated by stepped ones. But assessments show that this method is expensive and non-perspective for industry introduction. The most perspective for industry application is the FGM production technology by the extrusion method. Extruded FGM rods must have the geometry that corresponds to thermoelectric module legs dimensions. Material losses will amount 5-10% that allow to consider such technology as low-wasted one. Comparison of FGM legs assessed values obtained by induced technologies gives approximately the following results. Cost of 1 kg of legs obtained by the Czochralski method is $1800/kg, by the pressing is $550/kg, by extrusion is $450/kg. Subject to the necessity of additional study conduction on the pressing technology. The extrusion method has doubtless advantage and may be recommended to introduction FUNCTIONALLY-GRADED MATERIALS, THERMOELECTRIC POWER CONVERTERS, POROUS MATERIALS, MATERIAL SCIENCE, TECHNOLOGY, COMPUTER DESIGN, GENERATORS, COOLERS. Product Description popup.authors Черкез Радіон Георгійович popup.nrat_date 2020-04-02 Close