Vol 75, No 5-6 (2018)

Mathematical models of the dynamics of temperature fields during firing of complex shaped glass articles are presented for the example of container glass of cylindrical-conical and prismatic-cylindrical shapes. The critical sections corresponding to the minorant and majorant of the thermal field are shown. The results of computer modeling of the dynamics of the thermal fields of glass articles are presented.

Data from comparative analysis of the cooking and extraction properties of glass with the composition of type-E glass fiber with calcium colemanite and borate are presented. The physical and chemical properties of synthesized glasses based on calcium colemanite and borate are studied.

An investigation of the stiffness characteristics of fiberglass supports with cone angle about 89° is presented. A method is proposed for determining the modulus of elasticity in tension and compression in longitudinal and transverse directions of a composite support. Experimental studies were performed for measuring the modulus of elasticity in longitudinal and transverse directions, and formulas and empirical methods for calculating the modulus of elasticity and Poisson’s ratio in the transverse direction are proposed. It is showing that the modulus of elasticity in tension exceeds the modulus of elasticity in compression.

The effect of a modified coating, deposited on the surface of foam glass, on the ability to absorb electromagnetic radiation in the high frequency range was studied. It was established that a coating obtained on the basis of a liquid glass composition with ilmenite with 3 μm particles improves the radio absorption characteristics of the foam glass. For 1.5% ilmenite concentration in the coating composition the absorption coefficient of foam glass increases four-fold at 120 GHz and two-fold at 260 GHz compared with uncoated foam glass.

Modern systems based on innovative charging machines for batch and cullet charging of regenerative glass furnaces with horseshoe flame direction are examined. It is noted that such charging machines used in combination with adaptive control algorithms not only reduce the emission of dust and nitrogen oxides into the ambient atmosphere but also make the glassmaking process more efficient.

The factors affecting the sintering process for quartz ceramic are examined. The dependence of the post-firing density of blanks on the properties of the quart glass based slip is analyzed. It is proposed that the content of the highly disperse SiO₂ particles in the slip affects the properties of the ceramic material. The concept of a colloidal component is described. The particle-size distribution in the colloidal component is analyzed.

Examples are presented of the successful application of new types of diamond tools for high-efficiency processing of a wide class of materials such as glass, ceramic, sapphire, semiconductor materials, and different metals. The advantages of a bonded diamond tool based on heat-conducting polymer composite are shown.

Firing and non-firing high-silica composite building materials based on quartz sand and blast-furnace slag that are distinguished by high strength and durability, high density, abrasion resistance, and frost resistance were developed. They are readily manufactured and environmentally friendly and can be produced using extensive raw materials resources with minimum energy consumption. The technological and operational properties of the obtained materials are studied and applications are recommended.

The results of theoretical and experimental studies of methods for obtaining bitstone powder with relative density greater than 0.50 for subsequent sintering of high-density, aluminum oxide based, ceramic samples are presented. The indicated pressing density was achieved by picking the spherical fractional composition of corundum power based on known theoretical models of close regular and random packing of spheres of different size. The prospects for using the described methods in ceramic part fabrication technology are evaluated.

The results of an analysis of research on the development of compositions and methods of depositing high-temperature coatings to protect different metals and alloys are presented. It is shown that further development of heat-resistant sital ceramic coatings for protecting high-temperature nichrome steels and alloys is topical.