Melting. Melt Treatment
Gavrilin I.V. Cladding Aluminum Alloy Chips with Fluxes for Remelting in Reverberatory Furnaces
A new method of remelting Al chips in reverberatory furnaces with coating the surface of every chip particle with a thin layer of flux (cladding) is described. During melting the flux layer on the surface of every chip particle protects it from oxidizing. As a result, the melting loss of aluminum is reduced, and the yield increases to 75…80%. The flux consumption is only 1…3% of the aluminum mass, which is considerably less than usual (5…30%). The salt content in waste is reduced, the amount of waste (sludge, slag) is also reduced by 5…15%. As a result, the utilization of waste becomes easier. As a whole, the process of cladding chips is simple and economically beneficial.
Tribushevsky V.L. et al. Thermal Peculiarities of Melting Dispersible Materials in Rotor Furnaces
Recycling of dispersible metal waste in conventional furnaces results, first of all, in energy overconsumption. This makes foundrymen depart from using cheap and available metal waste. Calculation and obtained experimental data on using rotor furnaces for remelting dispersible oxidized metal waste have confirmed their efficiency.
Lyubimov A.A. et al. Mechanism of Diffusion Processes in Metal Melts and Efficiency of Their Electrophysical Treatment
A brief analysis of diffusion phenomena and methods for investigating these processes using electrophysical treatment of melts is given, which presents both scientific and practical interest for the theory of liquid state and blank production. High performance and precision of controlling the chemical composition of melt and its structure with minimal material, power and labor consumption will be possible as a result of changing the melt treatment conditions. This will help achieve optimal results of degassing, alloying, homogenizing, inoculation and refining.
Tsurkin V.N. et al. Indices of Successfulness of Using Out-of-furnace Treatment
Gorelov V.G. et al. Effect of Refining on the Quality of Low-Alloy Structural Steel Castings
Improvement of casting quality and reduction of their cost is achieved, first of all, through the quality of molten steel. Use of nonferrous metals production waste for deoxidizing and refining low-alloy steels allows not only obtaining a uniform and finely dispersed structure ensuring improvement and stabilization of mechanical characteristics and, accordingly, service durability of castings, but also departing from using expensive aluminum and thereby reduce the cost of castings.
Ganiyev I.N. et al. High-Temperature Oxidizing of Al-Sr-Master Alloys
By the methods of thermo- and massgravimetry, IKS and investigating into the interaction of alloy powders with water the kinetics of oxidizing and stability of double Al-Sr-master alloys and Al4Sr alloy alloyed with silicon, magnesium, titanium and rare earth metals have been investigated. It has been shown that the oxidizing of alloys is subjected to the parabolic law. The real oxidizing rate has the order of 10-4 kg.m-2.s-1. The optimum titanium and rare earth metal concentration does not exceed 0.4, and that of magnesium and silicon does not exceed 22…24 at. %.
Kalenik O.N. et al. Reduction of Iron Concentration in Secondary Aluminum Alloys
The authors have investigated the realizability of the process of refining secondary Al alloys from iron impurities under the conditions of small plants in recycling low-grade aluminum waste. Investigations were conducted on secondary alloys with different iron contents and ratios of added precipitator additives - manganese and chromium. The refining process is well combined with the flux treatment of melt in the process of melting waste and holding the melt in the furnace. The proposed refining method is ecologically safe and can be recommended for use in plants processing dispersed and oxidized aluminum waste.
Andreyev V.V. Processes and Outlooks for the Production of Vermicular Graphite Iron Castings
Shramko M.S. et al. Ways of Enhancing Mechanical and Performance Properties of High-Manganese Steel
The article is dedicated to investigations into the possibility of enhancing mechanical and performance properties of high-manganese steel castings. Effect of casting mold on the MnO and FeO contents in pre-tapping slag on mechanical and performance properties of castings has been determined. A deoxidizing mixture consisting of a silicon-containing nanopowder and carbon nanopowder with additions of surface-active substances has been developed, use of which allows to reduce the MnO and FeO contents in slag. An optimum quantity of the additive has been determined.
Vasenin V.I. Determining the High-Temperature Strength of Aluminum Alloys
Softening of D16, D20, AK41 and AK12L aluminum alloy castings after holding them at 300°C has been investigated. It has been shown that high-temperature tests should be conducted after holding specimens at that temperature for 100 hours.
21st Century Technologies
Nedelko A.Y. Advantages and Disadvantages of Contactless Temperature Measurement
Due to rapid development of electronic and digital technology over the recent years a great variety of different devices for contactless temperature measurement by thermal radiation - pyrometers have emerged in practice. Therefore the questions of evaluation of advantages and disadvantages of both the pyrometric method itself and comparative evaluation of different types of pyrometers is very topical. This is the question that is discussed in the article.
Information. News Items
Degtyarenko G.I. et al. Review of Information
Ivanova V.S. A Review of the Monograph by V.F. Terentyev "Fatigue of Metallic Materials"