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Information × Registration Number 0212U004327, 0107U002772 , R & D reports Title Development of new technologies and equipments for intensification of heat mass transfer and interphase actions at preparing and pouring of aluminium alloys and alloys on the base of titanium intermetallides using energy of electromagnetic fields. popup.stage_title Head Dubodelov Viktor I., Доктор технічних наук Registration Date 03-02-2012 Organization Physico-technological institute of metals and alloys National academy of Sciences of Ukraine popup.description2 Research object - casting magnetohydrodynamic (MHD) equipment, magneto-weighing installations, aluminium alloys, alloys on the basis of Ti intermetallides, automatic systems for control of equipment and technological processes, apparatus of express-control of metal quality. Purpose of work - research and determination of basic regularities of technological processes where electromagnetic actions are used, for intensification of heat-mass transfer and interphase interactions at preparing, pouring, and crystallization of aluminium alloys and alloys on the basis of Ti intermetallides, development of the systems and apparatuses for the control of such process control and equipment for their realization. Research methods and apparatus - analytic estimations with using of computer programs; physical and mathematical modeling and simulation; full-scale natural experiment; differential thermal analysis, spectral & metallographic analysis, X-ray structure and micro-X-ray spectrum analysis; express-methods for estimation of quality of cast samples; standard methods for determination of physical & mechanical properties of cast metal; optical and scanning electron microscopes for estimation of thin structure. There is developed new electromagnetic stirrer of pulsating magnetic field (EMP-PMF) for furnaces and mixers for melting of aluminium and its alloys. Its descriptions are explored; the rational modes of operations are defined. There are indicated the advantages EMP-PMF in comparison with equipment of similar technological function (for example, in comparison with electromagnetic stirrers of travelling magnetic field) - in particular, EMP-PMF has more simple construction, larger hydrodynamic efficiency (ca. on 20%), lower costs at manufacturing and exploitation. It is developed the requirements specification on designing of experimental-industrial sample of EMP-PMF. There is designed the structural & functional scheme of magneto-weighing installation, based on principle of measuring of the disconnected mass. It is realized as experimental aggregate, including spring-strain-gauge scales with elastically suspended platform and magnetodynamic installation MDN-6A for dosed electromagnetic pouring of aluminium alloys. The system of automatic control by dosed pouring of aluminium alloys is designed. At using of development in industrial terms the dosage error of aluminium melt does not exceed 2% from mass of dose. It is upgraded developed in PTIMA NASU method of computer thermal analysis of aluminium alloys. It allows forecasting (on melting stage) the properties of ingot. Efficiency of development is confirmed by natural experiments at research of influence of iron content on forming of intermetallide phases in aluminium alloy AK7. The effect of rise of modifying degree of basic phases in aluminium alloy at MHD treatment is ascertained. There are designed the special technological samples with increased sensitivity for the express-analysis of quality of aluminium alloys, in particular, estimation of their gas content and tendency to formation of gas-shrink defects. Authenticity of the information got by such express-samples is confirmed by parallel application of different well-known methods of estimation of quality of aluminium alloys. There are conducted researches of technology of making of cast on the basis of aluminium. It is manufactured high-quality cast composite Al-SiC (sizes of SiC particles make 100-120 µm), their by a volume part in aluminium matrix is 5%. The uniform distribution of such particles was provided at using of special MHD device. The rational modes of MHD processing and doping of SiC particles into aluminium melt are defined. The complex of researches on action of constant magnetic field on crystallization of binary aluminium alloys Al-Cu, Al-Fe, Al-Ni, Al-Cr is performed. It is set, that in all alloys at the slow cooling (~1 C/s) and solidifying in static terms, imposition of the weak (to 1 T) constant magnetic fields does not change their phase composition, but it causes the increase of range of sizes of intermetallides and their quantity due to the larger quantity of fine inclusions, especially at induction of field 0.1-0.5 T. It increases durability of such alloys considerably (in 4-6 times). Results are confirmed by experimental-industrial tests. There are performed researches of processes of electron-beam melting of alloys on the basis of Ti intermetallides in skull crucible of small and large capacity with electromagnetic stirring of melt. Technologies of the electron-beam melting of Ti-Al alloys are developed, including alloys with large content of Al (to 70%) and Nb (to 35%). It is shown possibility of making of ingots from these alloys with homogeneous structure by volume and with minimum of casting defects. There are developed rational modes of preparation of high-quality Ti-Si-B alloys with high level of strength properties ( 0,2~960 MPa) at room temperature, ponderable low temperature plasticity (~0.5%) and increased heat-resistance (349 MPa at 700 С). At that, the high level of their casting properties is retained. Experimental melting of Ti-Ni alloys (54.5% mass Ni, 45.5% mass Ti) with manufacturing of ingots for making of fibers of Ti nickelide are conducted. Also, results are used at performance of other science & practical works. Product Description popup.authors Богдан Кім Степанович Борисов Георгій Павлович Горюк Максим Степанович Дубодєлов Віктор Іванович Затуловський Андрій Сергійович Ладохін Сергій Васильович Середенко Володимир Олексійович Слажнєв Микола Андрійович Фікссен Владислав Миколайович popup.nrat_date 2020-04-02 Close