Daineko K. Low-temperature electrotechnical porcelain

Object of study: processes of phase formation and sintering of electrical porcelain in conjunction with the properties of the material. Objective: developing of compositions on the basis of national raw materials and determination of technological parameters for obtaining of low-temperature electroporcelain. Methods: theoretical research was implemented by using of complex physical-chemical calculations, by the finite element method. Сomposition and properties of the materials was realized by chemical, X-ray diffraction, differential thermal, gamma spectroscopic, infrared spectral, petrographic, electron microscopic analyzes. Theoretical and practical results: developed compositions and technological parameters for obtaining of low-temperature electroporcelain on the basis of national raw materials. Developed masses possible to obtain insulators with nominal voltage up to 10 kV, to reduce fuel consumption by about 30%. Scientific novelty: the first by using of complex mullite-forming intensifier (12 wt.% pyrophyllite and 0.3 wt.% TiO2) obtained an electroporcelain with properties: tensile strength of 31 MPa, volume resistivity 4.1*10^14 Оhm·cm, breakdown voltage 30 kV/mm, dielectric loss tg b*10^3 = 12.1 at 1200 °C; established that a maximum sintering porcelain (W = 0%) is provided by injecting 2 wt. % dolomite at reduced firing temperature; regularities of phase formation processes were established, which consist in accelerated sintering with modified melt and intensive formation of mullite microfibers (~ 30 vol.%). Degree of implementation: The results of the thesis are introduced in the educational process for the department of technology of ceramics, refractories, glass and enamels NTU "KPI". The developed porcelain is tested in certified laboratories of Ukraine and Germany. Scope: Enterprises manufacture of ceramics for electrical use, educational process.