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Information × Registration Number 0209U010530, 0108U000668 , R & D reports Title Physico-chemical foundations of creation of a new generation of fibre cathode materials with record high emission characteristics popup.stage_title Head Loboda Petro Ivanovich, Доктор технічних наук Registration Date 14-12-2009 Organization Faculty of аircraft and space systems NTUU "KPI" popup.description2 The physico-chemical foundations of receipt of multi-edge cathodes with an emitter from monocrystalline lanthanum hexaboride fibers were created. That opens possibility of making of cathode assemblies with current density of 107 А/см2 at voltage between an anode and cathode near 200 -300 V and considerable life cycle increasing of cathode assemblies. The technology bases include the first built fusion diagram of the quasi-binary systems LaB6-MоB2, LaB6-ScB2 and LaB6-W2В5. It is determined that the coordinates of eutectic points of the fusion diagrams depend on correlation of metal and boron atoms in phase component of alloys, the boundaries of which are determined by width of homogeneity range. The influence of kinetics and nature of components of the quasi-binary system on morphology of structural constituents of composites formed during the directionally crystallization of eutectic alloys from fusion is explored. It is experimentally determined that during the directed crystallization process the eutectics are formed as anomalous lamellar structures (LaB6-MoB2), fiber structures (LaB6-ScB2) and dendritic structures (LaB6 - W2B5). It is investigated that the mechanical and electro-physical properties of the directionally solidified alloys LaB6-MоB2, LaB6 - ScB2 and LaB6 - W2B5 correspond with properties of diphasic alloys. The cathode materials are tested on electron-beam and gas-discharge devices of electronic technique. It is determined that the emission properties of composition cathodes are higher than similar for monocrystalline lanthanum hexaboride cathodes. Product Description popup.authors Богомол Юрій Іванович Кисла Галина Павлівна Лобода Петро Іванович Сисоєв Максим Олександрович popup.nrat_date 2020-04-02 Close