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Information × Registration Number 0201U004808, 0195U025127 , R & D reports Title Processing of the scientific bases of produce by zone melting and directional crystallization of composites on the boride bases and chromium eutectic alloys popup.stage_title Head Trefilov Viktor Ivanovych, Paderno Yurij Borysovych, Rakyts'kyj Anatolij Mykolajovych, Registration Date 24-04-2001 Organization Frantzevich Insitute for Materials Science Problems of the Ukranian National Academy of Sciences popup.description2 The basic regularities of whisker's structure formation are defined for the directional crystallization of eutectic alloys on the borides phases base of rare-earth or alkaly-earth metals. The ground principles of control of structure formation processes of self-reinforced composition ceramic materials of this type are designed. The guidelines of formation of natural composites structure and of new materials producing with required performances for devices and articles of different assignment are proposed. The basic regularities of whisker's structure formation are defined for the directional crystallization of eutectic alloys on the borides phases base of rare-earth or alkaly-earth metals. The ground principles of control of structure formation processes of self-reinforced composition ceramic materials of this type are designed. The guidelines of formation of natural composites structure and of new materials producing with required performances for devices and articles of different assignment are propo sed. It is demonstrated, that the eutectic а-Cr - AlN from a pseudo-binary section of a system Cr - Al - N is perspective for creation of heat resisting and strong materials by a method of a directional crystallization for gas turbine engines. The eutectic Cr - AlN constitution differs by an irregularity. The doping of zirconium in an amount up to I of % assists growth of hexagonal base crystal of AlN only in a direction <0001>. Thus the transferring from a lamellar eutectic to rod takes place. Sharp response of the directional crystallization process of the chrome eutectic alloys to impurities of oxygen in a melt is established. At concentration of oxygen 0,005-0,008 mas. % the concentration supercooling and frustrating of front of directional growth takes place. Large scope of work on advancing machinery, mining of a method of refinement of chrome, solution of problems, bound with creation of heat and creep resisting ceramics, which is not interplay with molten chromic alloys, was executed. The directional crystallization was conducted by methods of a floating-zone melting and gradual chilling of an ingot in the gradient thermal field. The series of regularities of a directional crystallization of eutectics Cr - AlN and Cr - TiC is established. The high-temperature strength of eutectic alloys, heat resistance, thermal stability of pattern, and also capability of disperse reinforcing of a chromic matrix in an eutectic are investigated. Product Description popup.authors popup.nrat_date 2020-04-02 Close