INFLUENCE OF PURITY ON MICROSTRUCTURE AND STRENGTH CHARACTERISTICS OF REFRIGABLE MICROCOMPOSITES

The influence of the purity of the source materials on the structural and dimensional stability of micro-composites obtained in the process of controlled invariant phase transformation is investigated. The influence of high-temperature post-crystallization heat treatment on the processes of cleaning and increasing the technological ductility of structural materials is considered. The possibility of their practical use is discussed.

CRYSTALLIZATION HEAT OF HIGH HEAT CONDUCTING POLYMER COMPOSITES BASED ON POLYETHYLENE FILLED WITH COPPER MICROPARTICLES

The results of experimental studies of the specific heat of crystallization of polymer composites based on polyethylene filled with copper microparticles are presented. Data concerning the effects on the crystallization heat of the studied composites on such factors as the mass fraction of the filler and the cooling rate of the composites from the melt are presented. The corresponding studies were performed with a change in the mass fraction of the filler from 0.3% to 4.0% and the cooling velocity of the microcomposite from the melt from 1 K/min to 20 K/min. It is shown that the specific heat of crystallization decreases significantly with increasing speed VT and the mass fraction of the filler ω. The results of the comparison of the values of the specific heat of crystallization of polymer microcomposite, obtained by a method based on the mixing of components in a dry form and in a polymer melt, are presented. It was established that the first of the indicated methods correspond to large values of the heat of crystallization.

Investigation of Indentation Fracture Toughness (KIC) and Weibull Parameters of 0.25Li2O.2SiO2-0.75BaO.2SiO2 Glass-Ceramic

In the present study, mechanical properties of 0.25Li2O.2SiO2-0.75BaO.2SiO2glass-ceramic were investigated. The trans-formations‘ temperatures were determined by DTA instrument. The optimum nucleation temperature was found to be 540°C. This suggested the crystallization temperatures as 675, 720 and 800°C. After carrying out crystallization heat treatments, Vickers indentation test was applied. In order to determine the indentation fracture toughness (KIC), crack half-length ‚c‘ of the samples was measured. To calculateKIC, Young’s modulus,Eand the measured hardness,Hvwere used. UsingKICand probability of fracture ‚P‘, ln ln[1/(1 −P)] – lnKICgraph was drawn based on the Weibull distribution equation. Consequently, Weibull modulus, ‚m‘ and scale parameter, ‚K0‘ were determined and compared with each other.

DEVELOPMENT OF OIL INDUSTRIAL APPARATUSES FOR DEWAXING OIL WITH RECEIVING COMMODITY ASPHALT RESINOUS PARAFFIN PRODUCT

The analysis of the existing design of field apparatuses for dewaxing and crystallizing has shown their essential shortcomings which do not allow their use as field apparatuses for dewaxing oil. For elimination of these shortcomings there has been offered a design of a field apparatus for dewaxing oil using a continuous thermal hydrocyclone with the cooling and warming jacket. The characteristics of the process of asphalt resinous paraffin product receiving have been studied: temperature of melting - 54°C, crystallization temperature - 56°C, melting and crystallization heat - 189 kJ/kg, speed of sedimentation of solid particles - 1.6 · 10-3 m/s. Key parameters of the field apparatus for dewaxing oil are evaluated: height of each of 10 field apparatus for dewaxing oil bodies will make 1.0 m, diameter of the installation is 0.5 m. For conditions of V. Filanovsky field in the Northern Caspian Sea apparatus productivity on oil will make 648 t/h, on asphalt resinous paraffin product - of 19 t/h.