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Information × Registration Number 0215U004624, 0114U001935 , R & D reports Title Improvement of corundum ceramics technology and issue of trial lots of products. popup.stage_title Head Kryvoruchko P., Registration Date 02-07-2015 Organization Public joint stock company "The Ukrainian research institute of refractories named after A.S.Berezhnoy" popup.description2 The research subject is the alumina MARTOXID MR52 and MARTOXID MR70 brands, corundum ceramics slips on its basis. The purpose of the work is improvement technology of corundum ceramics. The research methods are chemical, petrographic, electronmicroscopic and physicomechanical. The researches on the improvement technology of corundum high-density ceramics are carried out and improved. The technological parameters of slip casting samples and products from alumina MARTOXID MR70 brand with using the additives DISPEX A40 and OPTAPIX AC 170 brands are established which allowed a number of difficult and expensive technological processes owing to possibility using of alumina MARTOXID MR70 brand without any previously. At the same time, the firing temperature of ceramics is decreasing down to 1580 °C, on 100 °C. Researches of the alumina MARTOXID MR52 and MARTOXID MR70 brands produced by "MARTINSWERK GmbH" company "ALBEMARLE" corporation (Germany) are carried out. These alumina are characterized by high content of Al2O3 and consist of finely dispersed particles of alpha-Al2O3 with developed surface that have different morphology are established. The aggregates which contain in the alumina of both brands are decay on fine-dispersed particles after adding of water. The aggregates of alumina MARTOXID MR52 brand decay immediately and in alumina MARTOXID MR70 brand this process is longer and reach 24 hours after adding of water. The rheological properties of slips from alumina MARTOXID MR52 and MARTOXID MR70 brands basis were researched. It was established that these alumina form the slips with use of dispersing additives satisfactory properties (the relative viscosity and speed setting the crock), however it is necessary to improve the stability of the slips. The corundum ceramic samples which made from alumina MARTOXID MR70 brand after firing at temperature 1580 °C characterized by high properties while this temperature is insufficient for sintering simples which made from alumina MARTOXID MR52 brand. The effect of dispersing additive DISPEX A40 brand produced by "BASF Construction Polymers GmbH" company (Germany) and hardening additive OPTAPIX AC 170 brand produced by "ZSCHIMMER & SCHWARZ GmbH & Co KG CHEMISCHE FABRIKEN" company (Germany) on rheological and casting properties of the slips from alumina MARTOXID MR70 brand were investigated. As a result of researches it was established that the samples which were formed by slip casting method with the optimal amount of the additives DISPEX A40 and OPTAPIX AC 170 brands after firing at temperature 1580 °C is characterized by high properties, namely apparent density 3,90-3,93 g/cm3 and open porosity 0 %. The microstructure of samples consists of isometric crystals with prevailing size 8-20 microns and such structure is typical for corundum high-density ceramics. At the trial plant of PJSC "THE URIR NAMED AFTER A.S. BEREZHNOY" the manufacture improvement technology of high-refractory corundum high-density products of КОПМ brand according to ТУ У 23.2-00190503-374:2012 by slip casting method in gypsum molds from alumina of MARTOXID MR70 brand with additives using of DISPEX A40 and OPTAPIX AC 170 brands was mastered. According to requirements of technical documentation and contacts terms on trial plant of PJSC "THE URIR NAMED AFTER A.S. BEREZHNOY" the trial lots of high-refractory corundum high-density products of КОПМ, КОПМТ, КОП brands and fireclay-cordierite products of ШКДТ-3 brand were manufactured. The trial lots of made corundum and fireclay-cordierite products were delivered to the customers in financing volume. The work should be continued in direction of future improving of corundum ceramics technology, made by different ways of shaping, and decreasing of linear shrinkage of products during the firing. Product Description popup.authors Карякіна Е.Л. Костирко І.Ю. Крахмаль Ю.О. Кущенко К.І. Мішньова Ю.Є. Сінюкова О.І. popup.nrat_date 2020-04-02 Close