卷 58, 编号 3 (2017)

Results are provided for a study of nano modification on pitch rheological properties. It is established that addition of carbon nano materials to pitch facilitates structural transformations, more uniform impregnation of carbon-carbon structural materials, a reduction in viscosity, and an insignificant change in wetting angle.

Results are provided for analysis of research results obtained by different scientific schools for abrasive-diamond and boron nitride machining of metal and ceramic materials. Acombined grinding efficiency coefficient RcEfG is suggested for measuring the ceramic grinding efficiency. Mathematical models are obtained of surface roughness for index Ra with surface and circular grinding of quartz ceramic based on SiO₂.

Refining slag used in out-of-furnace metal processing units, due to significant content in it of the unstable phase—dicalcium silicate, is prone to decay due to its polymorphous transformations, accompanied by an increase in the volume of the crystal lattice. Getting into cracks of the furnace lining, the slag can cause its destruction. The results of investigating the mechanism of stabilizing the refining slag by introducing alumina flux to it, while giving it the properties of mineral binders, are presented here.

The main stressed state features are established at a boundary between layers of a two-layer TiC/TiN coating applied to nitride ceramic under action of concentrated and distributed forces. The effect of ceramic basic structural element on stresses formed in TiC/TiN-coating underlayers in contact under action of force loads is determined.

The possibility is studied of preparing ceramic proppants based on natural Kazakhstan aluminosilicate raw material. It has been shown that Arkalyk refractory clay and Red October bauxite are highly basic aluminosilicate raw materials containing 48.3 and 62.O% Al₂O₃ (as calcined substance) respectively. Bauxite has a high content of iron impurity (22.3%). The effect has been studied of content of Red October bauxite and previously heat treated raw material on sintering and strengthening of ceramic composites with sintering firing in the range 1350 – 1500°C. It is established that the optimum for preparing lightweight ceramic proppants is raw material consisting of refractory clay with addition of 20 – 30% bauxite. The efficiency is demonstrated of raw material heat treatment at 1000°C for improving the density and strength of ceramic specimens. Lightweight aluminosilicate proppants with properties satisfying the specifications of GOST R 51761–2013 for aluminosilicate proppants are prepared for the oil and gas recovery industry.

A dust and air flow approaching a local ventilation suction funnel is considered. Limiting trajectories of the dust particles are constructed for different Stokes numbers and different rates of the incoming (approach) flow. The effect of the angle of inclination of the suction funnel and its length on the ventilation coefficient is discussed.

The name of the third author should read S. N. Grigor’ev.

The possibility is considered of preparing intermediate ladle concrete partitions using cheap materials. It is shown that in order to prepare high quality concrete refractory materials capable of slow hydration are considerably important. In addition, it is necessary to use metallurgical production waste considerably cheapening refractory objects.

Aversion is proposed for chemical and mineral classification of technogenic refractory raw material. Secondary mineral resources are considered of essentially silica composition represented by four large-scale technogenic formations.Waste-free technology is developed for processing sub-standard material with preparation of enriched raw material for producing quartzite filler grade ZVK-97, building gravel, and sand. The suitability is established for the fine-grained fraction of silica waste (enrichment tailings) for preparing molding, filter, building materials, and also in a raw material for producing some grades of packaging glass and other materials. The possibility is demonstrated of using regeneration products of exhausted molding mixes for preparing high quality dinas. Microsilica is studied comprehensively, on whose basis promising areas for its utilization are developed.

Questions are considered for improving the energy efficiency of electric modular-pouring furnaces due to use of thermal exergy of expanding vermiculite grains. In order to create favorable conditions for transformation of accumulated heat into energy from final dehydration and structure formation a so-called “zero” module is introduced into the furnace construction, not requiring electrical energy. In contrast to other versions, this additional module is vibration-active and provides movement of expanded grains with single-layer continuous flow without breaks or gaps. This flow structure makes it possible to use heat accumulated by vermiculite and inert material most effectively.

The bases of contemporary quartz ceramic technology and refractories were laid down in the second half of the 1960s. In this technology single-stage methods were implemented for preparing quartz glass (fuzed quartz) HCBS, and diluted and stabilized wet-milled highly concentrated binder suspensions (HCBS) by gravitational mechanical stirring and activated sintering of highly dense semiproduct. The bases of technology developed in this way have been implemented extensively in the manufacture of other ceramic and refractory materials prepared by HCBS technology, and also in the production of materials for rocket, aviation, and a number of other branches of technology.

An optimum charge composition is developed for preparing porous permeable cermet SHS-materials with prescribed operating properties for cleaning exhaust gases of industrial installations and internal combustion engines. Physicomechanical properties of the materials obtained are determined with a different content of charge components and the range of vibration frequency is established suitable for material operation as filters. It is shown that addition of 0.5 – 1.5 wt.% of alloying elements to a charge increases SHS-material mechanical strength and shock resistance.