The influence of the glass phase of the eutectoid composition on the sintering of corundum masses is considered. It has been established that an additive corresponding to the composition of the eutectic of the CaO - Al 3 O 3 system, melting at a temperature of 1395 ° C, improves the performance properties of corundum concrete as a result of activation of its sintering. Tab. 1, bibliography: 4 titles.
The relationship between the temperature dependence of X-ray luminescence and the change in the parameters of the unit cell of BeO has been established. Lattice deformation and pyroelectric fields lead to the formation of point defects (which are luminescence centers) on which excitons, as well as holes or conduction electrons, are likely to be localized. Il. 3, bibliography: 7 titles.
Methods for determining frost resistance of facing materials and products are considered. Experimental results are presented. A Lithuanian standard has been developed (LST 1413.12: 1998). The standard specifies the grades of composites and their frost resistance in accordance with three different categories of use. Tab. 2, ill. 1, bibliography: 3 titles.
The effect of additives (within 15 - 30%) of dispersed alumina with different contents (up to 2.3%) TiO 2 and MgO on the properties of a porous permeable material based on electrofused corundum of different dispersion has been studied. The obtained porous ceramics with open porosity up to 40% and bending strength up to 25 MPa, characterized by high filtration efficiency and chemical resistance. Tab. 1, ill. 1, bibliography: 3 titles.
The results of studying the phase separation of zirconium-containing aluminoborosilicate glaze glasses at the stages of cooking and heat treatment are presented. The influence of the composition of glasses on the features of the formation of their phase composition and structure is considered. The possibility of obtaining low-melting glaze coatings with desired properties is shown. Il. 5, bibliography: 8 titles.
The problems that restrain the widespread use of unshaped refractories are considered - the need for close coordination of the actions of specialists in the field of binding materials and specialists in the field of ceramics and refractories, organizational problems, especially the establishment of engineering support for manufactured products. The necessity of testing the deformation properties of refractory materials at the manufacturer's office under the conditions that will be during their operation is noted. Taking into account the pieceiness and low-volume of the manufactured products, it is advisable to engage in their production for small and medium-sized businesses with an orientation to the regional market. Il. 6, bibliography: 12 titles.
The possibility of obtaining uniform precipitates of aluminum oxide of sufficient thickness from its suspensions in an aqueous medium with the addition of an electrolyte is considered. The effect of the concentration and nature of the electrolyte on the thickness, moisture content, specific yield, and the rate of sedimentation is shown. Il. 1, bibliography: 4 titles.
The results of theoretical calculations and experimental studies of the structure of the three-component system BaO - Al 2 O 3 - SiO 2 in the subsolidus region at temperatures of 1200 - 1400 ° C are presented. ... A complete partition of this system into elementary polytypes is carried out, a topological graph of the relationship of these polytypes is given, and a geometrotopological characteristic of binary and ternary compounds included in its composition is given. Tab. 2, ill. 2, bibliography: 26 titles.
The dependences of the LTEC of an engobe coating on the LTEC of its constituent components have been investigated. It was found that the TLEC of the contained frit, as well as the amount of sand, has the greatest influence on the LTEC of engobe coatings. Additives-modifiers were selected to correct the rheological properties of the engobe slip and the whiteness of the engobe. Il. 2, bibliography: 3 titles.
The BET method was used to study the porosity in nanoporous ceramics prepared by pyrolysis at 600 ° C of an organosilicon polymer. The samples were pressed from fractionated granules obtained by single and double grinding in a planetary mill of the polymer hardened and heat-treated at 200 ° C. After an increase in the size of the granules over 250 µm at a single and 1000 µm at a double grinding, the specific surface area determined by the nanopores dropped sharply. An explanation of the results obtained is given from the standpoint of synergetics. Il. 4, bibliography: 10 titles.
