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Information × Registration Number 0220U000601, 0119U002369 , R & D reports Title Researchers of corundum ceramics microstructure in the rang of temperatures 600-1580 °С and pilot batches out put of corundum and chamotte-cordierite compositions ceramics products popup.stage_title Head Kushchenko K., Registration Date 11-06-2020 Organization Public joint stock company "The Ukrainian research institute of refractories named after A.S.Berezhnoy" popup.description2 The research object is a microstructure of corundum ceramics from alumina brand MARTOXID, which is made by the method of slip casting. The purpose of the work is an improvement of corundum ceramics technology. The research methods are chemical, petrographical, thermomechanical, electron microscopic ones. By electron microscopic method the microstructure of corundum ceramics samples of two compounds made by slip casting method of alumina brand MARTOXID after firing in the rang of temperatures 600 - 1580 °C was investigated. It was established that, irrespective of the composition, after firing at 600 °C, weak contact was observed between alumina grains, at 1000 °C the initial stage of crystalline corundum grains formation was observed, and after firing at 1200 °C - the structure was compacted and alpha-Al2O3 crystallized. After firing at 1400 °C, the samples microstructure of composition 1 was represented by crystals of a tablet type corundum, preferred particle size of ~ 2.5-3.0 microns, and composition 2 - by separate particles of a round and oval shape, preferred size of ~ 1.5-2.0 microns, which are interconnected by inter-crystalline layers. The microstructure of corundum ceramics samples of both compositions after firing at 1500 °C was similar and consisted of crystallized corundum grains, preferred size of ~ 1.5-2.0 microns, among which there were larger grains of alpha-Al2O3 size of ~ 2-8 microns, and crystalline growth rates were observed. After firing at 1580 °C the samples microstructure was represented by a fine-grained structure of virtually defect-free corundum grains size of ~ 0.5-3.0 microns, among which there were grains size of ~ 5-10 microns, and the crystal growth were more pronounced, which indicates almost complete sintering of corundum ceramics. Based on the obtained resultes the technology of corundum ceramics was improved by optimizing the firing regime. In JSC "The URIR named after A.S. Berezhnoy" the pilot batches of high refractory products were produced. The work should be continued in direction of future improving of corundum ceramics technology, made by different ways of shaping. Product Description popup.authors Карякіна Е.Л. Крахмаль Ю.О. Мішньова Ю.Є. Шулик І.Г. popup.nrat_date 2020-10-01 Close