MODELLING OF A THREE-DIMENSIONAL PROBLEM OF DISTRIBUTION OF HARMFUL IMPURITY IN THE RIVER A RECURRENTLY-OPERATIONAL METHOD

In this article the decision of a three-dimensional problem of diffusion is considered by a recurrentlyoperational method which describes process of distribution of harmful impurity along a watercourse. The received numerical results on the COMPUTER where it is possible to define for what time are resulted there is a distribution and river clarification. The received results are illustrated in drawings.

USE OF THE PROCESSED GALVANIC SLIMES AS ONE OF THE RECYCLING OF TECHNOLOGIES

The analysis of a situation in the sphere of galvanic production recycling is presented in work. Galvanic production is one of the most dangerous sources of environmental pollution. Mainly superficial and under-ground sources are soiled. It occurs because of the large volume of the sewage containing harmful impurity of heavy metals, inorganic acids and alkalis, surfactants and other highly toxic connections and solid waste is formed. Especially because a reagent way of the sewage containing heavy metals in a slightly soluble form. Assessment of harm of chemical components of galvanic slimes is presented. The possibility of slimes processing by hardening in concrete mix as a part of paving slabs is considered. The paving slabs with use of slimes as the painting pigment is offered. The order of carrying out tests for definition of galvanic slimes safety using for production of construc-tion materials (paving slabs) is given. Influence of slimes introduction on mechanical properties of products is shown. The dependence of products color on amount by the entered galvanic slime and possibility of color schemes correction are shown.

Studying Influence of Rotation an Electrode on the Number Nonmetallic Inclusions in Received Eletroslag Metal

Quality improvement metal, in particular decrease content nonmetallic inclusions, is very important tasks as mechanical, thermal and anticorrosive characteristics metal depend on it. Electroslag remelting well influences quality on metal: content harmful impurity decreases, metal density increases, nonmetallic inclusions are removed. A method quality improvement metal by means of removal of nonmetallic inclusions at classical electroslag remelting and remelting with rotation electrode it is offered in this article. Also metallographic surveys experimental materials received are given in article which showed that ESR with rotation electrode deletes nonmetallic inclusions for 55-56 % more effectively, than classical remelting.

Influence of Nickel Addition on Properties of Secondary AlSi7Mg0.3 Alloy

This paper deals with influence on segregation of iron based phases on the secondary alloy AlSi7Mg0.3 microstructure by nickel. Iron is the most common and harmful impurity in aluminum casting alloys and has long been associated with an increase of casting defects. In generally, iron is associated with the formation of Fe-rich intermetallic phases. It is impossible to remove iron from melt by standard operations. Some elements eliminates iron by changing iron intermetallic phase morphology, decreasing its extent and by improving alloy properties. Realization of experiments and results of analysis show new view on solubility of iron based phases during melt preparation with higher iron content and influence of nickel as iron corrector of iron based phases.

Elimination of Iron Based Particles in Al-Si Alloy

This paper deals with influence on segregation of iron based phases on the secondary alloy AlSi7Mg0.3 microstructure by chrome. Iron is the most common and harmful impurity in aluminum casting alloys and has long been associated with an increase of casting defects. In generally, iron is associated with the formation of Fe-rich phases. It is impossible to remove iron from melt by standard operations, but it is possible to eliminate its negative influence by addition some other elements that affect the segregation of intermetallics in less harmful type. Realization of experiments and results of analysis show new view on solubility of iron based phases during melt preparation with higher iron content and influence of chrome as iron corrector of iron based phases. By experimental work were used three different amounts of AlCr20 master alloy a three different temperature of chill mold. Our experimental work confirmed that chrome can be used as an iron corrector in Al-Si alloy, due to the change of intermetallic phases and shortening their length.

Use of Multicomponent Phase Diagrams for Designing High Strength Casting Aluminum Alloys

Principles of optimization of the phase constitution of a new group of aluminum alloys, i.e., sparingly alloyed high-strength casting nickalyns are considered. The Thermo-Calc software and experimental methods (LM, SEM, TEM, EPMA, etc.) were used for analyzing the phase constitution of the Al–Zn–Mg–Cu–Fe–Ni system as applied to high-strength (UTS>450 MPa) aluminum alloys based on (Al)+Al3Ni and (Al)+Al9FeNi eutectics. Both eutectics possess the fine structure but the latter is more expedient due to the lower content of nickel. Then the iron becomes an alloying component rather than a harmful impurity. It is shown that the addition of copper substantially complicates the phase constitution and strongly decreases the equilibrium solidus, which limits the possibility of carrying out the high temperature annealing. This can negatively affect the spheroidization of the Al3Ni and Al9FeNi phases. A set of calculated and experimental data is used to show the perspectives of replacement of the existing high-strength casting aluminum alloys based on Al–Cu system (AA201, 206, 224) by the sparingly alloyed low-copper weldable nickalyn Al6Zn0.5Ni.

Effect of the AlCr20 Addition on the Microstructure of Secondary AlSi7Mg0.3 Alloy

This paper deals with influence of chrome addition and heat treatment on segregation of iron based phases in the secondary alloy AlSi7Mg0.3 microstructure by chrome and heat treatment. Iron is the most common and harmful impurity in aluminum casting alloys and has long been associated with an increase of casting defects. In generally, iron is associated with the formation of Fe-rich intermetallic phases. It is impossible to remove iron from melt by standard operations, but it is possible to eliminate its negative influence by addition some other elements that affect the segregation of intermetallics in less harmful type or by heat treatment. Realization of experiments and results of analysis show new view on solubility of iron based phases during melt preparation with higher iron content and influence of chrome as iron corrector of iron based phases.

Low-Temperature Catalytic Clearing of Gases of Thermal Power Station from Harmful Impurity in the Presence of the Cobalt Complexes Fixed on a Polymeric Matrix

The results of optimization of catalysts for gases clearing from sulfur dioxide using processes of oxidation are presented in this work. The researches carried out with the help of modern methods: kinetic, IR-, UV-spectrophotometric, viscometry, LG-chromatography, redox-potentiometric. It is shown, that developed complexes of transitive metals immobilized on a polymeric matrix are highly effective and stable catalysts for the sulphur dioxide oxidation processes. By the example of cobalt compounds the reactions kinetic investigated in details, the kinetic equation is received, allowing to optimize process of gases clearing from sulfur dioxide, kinetic and thermodynamic parameters of process are calculated.

Summary of the Function of Sn in Iron and Steel

In the steel industry Sn is always regarded as harmful impurity element, one of "Five harmful elements", which affects the welding property and equality of steel product especially the equality of continuously cast bloom and causes hot brittleness, temper brittleness, crack and fracture. While Sn element also has a vital influence on free-cutting steel, electrical sheet, cast iron and stainless steel. NSSC developed ferritic stainless steel containing low Sn and Ni content improving the corrosion resistance performance and the workability significantly. So the Sn element, as cheap alternative adding element, can substitute for Cr and Ni. It's helpful to study the effect of tin in the iron and steel and develop new stainless steel products of high equality conserving chromium resources. In this way it will promote the variety and technique of stainless steel, ensure the independence on resources and conserve resources remarkably.

Low Resistivity Aluminium Alloy of High Tensile Strength and Elongation

Through testing the mechanical properties and electrical property, the conductive aluminum alloy with high strength and elongation was obtained by adjusting the content of Fe, B and misch metal elements constantly, and the influence mechanism of the add elements was discussed by observing microstructure morphology of the aluminum alloy. The results indicated that the addition of Fe could effectively improve the tensile strength of commercial aluminum, while the addition of misch metal could change the existence form of Fe, thus to compensating for the decrease of elongation because of the addition of Fe. On the other hand, the addition of appropriate B could remove the harmful impurity elements of the aluminum alloy and refining the grain, so as to reduce the resistivity of the aluminum alloy with adding iron and rare earth elements. Finally, the optimum was obtained which was the composition of 99.18%Al-0.75%Fe-0.05%Re-0.02%B, the tensile strength was 103MPa, the elongation was 30.98% and the resistivity was 2.737×10-8Ω•m.