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Information × Registration Number 0223U002288, 0117U002459 , R & D reports Title Developing principles of the structural engineering and the technological foundations of material making for the impregnated cathodes of new generation with high-emission and long-life thermoionic properties popup.stage_title Head Hetman Olga І., Доктор технічних наук Registration Date 14-02-2023 Organization Institute of Problems of Materials Science named after IM Frantsevich of the National Academy of Sciences of Ukraine popup.description2 The principles of structural engineering and technological bases of manufacturing high - emission and lifetime ScBa-cathodes have been developed. The technical conditions of TU U 25.5-05416930-018-015 (I): 2021 for the emission-active substance for high-emission and lifetime impregnated ScВa-cathodes with high reproducibility of emission characteristics have been elaborated. It is established that impregnated ScBa-cathodes, the composition and structure of the emitter layer of adsorbed substances which are determined by microscopic level parameters, are characterized by the work function 1.65–1.71 eV at 1070 K and lifetime of at least 10 000 h at current density 15 –20 A / cm2 and elevated test temperatures of 1230 and 1340 K in a vacuum of 10-4 Pа. A ScBa-cathode with an additional mesoscopic nanostructural level is obtained, which is characterized by the work function of 1.29 eV at 950 K and 1.34 eV at 1000 K, a saturation current density of 100–140 A / cm2 at temperatures of 1200–1400 K, and more than 20 A / cm2 at 950 K and optimum operating temperatures of 950–1100 K. The durability of such a ScВa-cathode is over 20,000 h at a test temperature of 1150 K and a current density of 10 A / cm2 and at least 2,000 h at a current density of 80 A / cm2. and a test temperature of 1250 K. The increase in the functional characteristics of ScBa cathodes is due to the creation of an additional mesostructural level - nanosized tungsten-based film with uniform distribution of anion-deficient perovskite-like phase beta-Ba2ScAlO5 and anionic conductor of scandium tungstate. The research results meet high international standards.The developed scandalous ScB-cathode is offered as the main candidate for ultrahigh-frequency electrovacuum devices with high power. Product Description popup.authors Kirkova Olena G. Makarenko Olena S. Panichkina V. V. Podolyako T. I. Radchenko Petro Ya. Skorokhod V. V. Sokol L. K. Filippov Mykola I. Khachvankyan R. V. popup.nrat_date 2023-02-14 Close