Vol 75, No 1-2 (2018)

Glass compositions for fabricating hollow glass microspheres were developed. The basic physical and technical characteristics were studied and the dependence of the properties on the glass composition was determined. It is shown that the rheological properties of glass near the liquidus temperature affect the release of dissolved gases present in the glass. It is established that 20 – 200 μm in diameter hollow glass microspheres can be obtained.

Methods of monitoring the stress-strain state of strong elements for special glazing used in aircraft as well as for inclusion in transparent body armor are presented. Data obtained from monitoring of witness samples of chemically tempered glass by means of a scattered-light polariscope and a destructive, centrosymmetric, bending method are presented. On the basis of these data conclusions are drawn on whether or not nondestructive methods of monitoring can be used as indicators of the stress-strain state of a glass surface.

The results of an investigation of the solid-phase synthesis and technological parameters for the production of weather-resistant gray, gray-yellow, and gray-brown ceramic pigments are presented. The physical-chemical and technological properties of the synthesized pigments were investigated.

A batch composition was developed for producing facing ceramic based on low-plastic clay. Titanium dioxide (10 wt.%), boric acid (5 wt.%), and galvanic slurry (to 5 wt.%) are introduced into the batch as additives. The influence of the batch components on the composition and structure of the developed material as well as the basic operating properties of the articles obtained on the basis of the new composition is investigated. The results confirm the possibility of synthesizing environmentally safe ceramic obtained as a result of the glazing (self-glazing) effect on the surface of articles and on the surface of the ceramic particles over the entire volume of the ceramic.

Samples of models of OHL supports based on basaltic and glass roving in the form of tubes with five different winding schemes were fabricated: longitudinal-transverse, spiral-longitudinal, spiral-longitudinal-transverse, and spiral with angle 30 and 60° with respect to the axis of the mandrel. The elastic-strength properties were investigated in tests by transverse bending and it was shown that the largest values of the elastic modulus obtain with the longitudinal-transverse winding scheme and the smallest values with spiral winding at angle 60° with respect to the axis. The elastic modulus of the basalt-plastic tubes is someone smaller than that of glass-plastic tubes, which can be explained by the lower linear density and more uniform packing of the used glass roving.

It is proposed that the redox conditions for firing porcelain be monitored in situ (‘on site’) according to the reflection spectra in the UV-VIS-NIR region. It is shown that the difference in terms of the color characteristics of glazed porcelain is correlated with reflection at λ ~ 1100 nm, which depends on the ratio Fe²⁺/Fe³⁺ predominantly in the composition of the glaze. It was found that as the intensity of the luminescence band due to the optically active center Fe³⁺ increases, the reflection coefficient of the glazed porcelain at λ ~ 1100 nm also increases.

The processes occurring during the formation of hollow microspheres in a thermal plasma jet on the basis of ash-slag waste from CHP in Kemerovo Oblast are studied. The results of physical and chemical studies (scanning electron microscopy, energy-dispersive x-ray and infrared spectroscopy) of the initial raw material and the obtained microspheres based on it are presented. A comparative analysis is performed of hollow microspheres obtained by the conventional method in batch-type furnaces at CHP in Kemerovo Oblast and microspheres obtained using thermal plasma.

The properties and advantages of fiberglass and carboplastic as well as their applications in the design of vehicles are examined. The possibility of increasing the recyclability of vehicles at their design stage by using lightweight recyclable materials is discussed. The existing methods of handling fiberglass wastes are analyzed and it is shown that there is a need to develop effective commercial technologies for recycling these materials.

The ultimate strength of diatomite in compression was studied as a function of temperature in the range 50 – 700°C. The ultimate strength in compression at temperature 450 – 500°C is approximately a factor of 2 greater than the strength under normal conditions. This makes it possible to organize the process of heating diatomite-based lining of high-temperature furnaces more efficiently.

The action of pulsed laser radiation on a plate is studied as a quasi-static problem of thermoelasticity. An analytic relation expressing the thermal strength condition for a plate is derived, making it possible to determine non-destructive regimes of laser processing in the case where the diameter of the laser beam is smaller than the diameter of the worked plate. The obtained results were checked experimentally.