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Information × Registration Number 0304U002273, 0103U004339 , R & D reports Title Finalizing and putting into production the technology of corundum ceramics and the manufacture of trial lots of products. popup.stage_title Доробка та освоєння технології корундової кераміки та виготовлення дослідних партій. Head Kryivoruchko P., Registration Date 18-03-2004 Organization The open joint stock company " The Ukrainian research institute of refractories named A.S.Berezhnoy" popup.description2 The research object - corundum ceramics.The work purpose - perfection and putting into production corundum ceramics and the manufacture of trial lots. The research methods:chemical and spectral analysises, optical and electron microscopy,determination procedure of electrokinetic Z-potential, pH determination using pH-meter pH 673, working procedure of testing for the thermal shock resistance of corundum ceramics РМИ 320-49-2002, strandard procedures for the determination of open porosity, apparent density; compression strength. The research on the perfection and putting into production a technology of ultradense corundum ceramics has been carried out.It was established that the addition of 20% of fine dispersive reactive alumina of CT brand 3000 SG in the technology of ultradense corundum ceramics using a method of slip casting allows to broaden the natural raw materials depot and to simplity a technological process of a corundum ceramics manufacture as a result of the firing temperature decrease ofproducts from 1750o up to 1580o C and to increase its strength during bending up to 320 MPa instead of 250 MPa in ceramics without additions of reactive alumina. The utilization of alumina of CT 3000 brand with an addition of 3% of a mixture of dispersive additions ADS and ADW allows to produce by means of a pressyre casting from thermoplastic slips and a firing at the temperature 1580 o C highquality ultradense abrasive resistant intricately shaped products with apparent density 3,85 g/cm3 which makes up 96,5 from theoretical density. The research on the technology of corundum ceramics with additions of ZrO2 has been conducted. It was ascertained what at pH 3,5 a vacuum treated slip from corundum powder with an addition of 10% ZrO2 is characterized by minimum value of dynamic toughness and by largest density of the a green body - 2,90 g/cm3. It was shown that a corundum ceramics with additions 5 and 10% of ZrO2 possesses largest thermal shock resistance - T confornably 230o and 200o C. This thermal shock resistance is determined by the difference of temperatures at which strength losses more than by 30% are observed compared with a ceramics instead of 190 o and 170 o C modified by MgO and with an addition of TiO2. The results of the search research of a ball milling in a corundum mill thermally treated alumina at 1550 o C with an addition of ZrO2 were given. Trial lots of corundum products of 20 standard sizes of КОМП and КОПМТ brands which meet requirements of ТУУ 26.2-00190503-221-2003 according to 19 contracts with industrial works of Ukraine, as well remote and nearest foreign contries. The work should be continued for the purpose of researching of the ball milling of alumina with additions of ZrO2, as well as decreasing thermal treatment temperature of alumina impregnated with a soluble acid of zirconium and advisablity of application of dispersing additions. Product Description popup.authors popup.nrat_date 2020-04-02 Close