Electric Melting Research Articles

Thin film metallization by magnetron sputtering from highly pure molybdenum targets

Both vacuum and powder metallurgy methods of preparation of molybdenum for magnetron-sputtering targets were studied. It is found that a combination of multiple-electron-beam melting and electric arc vacuum melting is an optimal metallurgical method to obtain highly pure molybdenum polycrystalline ingots for massive magnetron targets. Highly sensitive methods of analysis were used to characterize the molybdenum target. The specific resistivity of deposited thin molybdenum films was found to be strongly dependent on both the sputtering conditions and the initial target purity.

Effect of Aluminum and Neodymium Admixtures on Devitrification of Silica Glasses

This investigation concerned the devitrification kinetics (in the temperature range 1100° to 1500°C) of silica glasses doped with aluminum oxide (0.1 and 1.0 mol%), neodymium oxide (0.08 and 0.25 mol%), and with aluminum and neodymium oxides simultaneously, at their mutual molar ratio close to 4. The glasses were obtained by electric melting of quartz under vacuum and by the sol/gel method. On the basis of the obtained results, conclusions have been drawn concerning the mode in which the admixtures become incorporated into the silica glasses as well as the structural differences between the melted and sol/gel glasses.

Periclase-carbon tubes for protection of a stream of metal from secondary oxidation

The service conditions of tubes for protection of the stream of metal from secondary oxidation in No. 2 Electric Melt Shop of Oskol Electrometallurgical Combine have been studied, a method for production of periclase-carbon tubes has been developed, and an experimental lot has been prepared at Novomoskovsk Refractory Plant. The tests under conditions of No. 2 Electric Melt Shop of Oskol Electrometallurgical Combine showed the promise of use of periclase-carbon materials in production of tubes for protection of the stream of metal from secondary oxidation.

A corundum hydraulically hardening compound with addition of baddeleyite for steel ladle vacuum degassing vessels

A corundum hydraulically hardening compound with addition of baddeleyite has been developed. In comparison with standard production MKN corundum compound it makes it possible to prepare concretes with improced physicotechnical characteristics, to increase the wear resistance of nozzle outer linings of batch and circulating vacuum degassers operating in electric melt and converter shops, to reduce labor costs for intermediate repairs, and to decrease the consumption of materials. To obtain more representative data it is desirable to conduct broad production tests of the new compound.

Electric melting of borosilicate glasses in a furnace with plate electrodes

On etudie la fusion electrique de verres de borosilicate dans un four equipe d'electrodes plates

Technological peculiarities of electric melting of houshold glass

Technological peculiarities of electric melting of houshold glass

Hearths of electric arc steel melting furnaces

Preparation of 100-ton electric furnace hearths with a monolithic layer thickness of about 400 mm of fine-grained periclase powders of rational grain size distribution makes it possible to increase their service life without major repairs to 3000-3500 heats instead of 1500-2000, to use the heart without preventive repairs for up to 70 heats, to increase furnace productivity and reduce down time for hearth repairs by 15-25%, to reduce the consumption of periclase brick by 40-50%, and to eliminate the use of chamotte parts with maintenance of the specific consumption of periclase powder for preparation and repair of hearths within limits of 4-6 kg/ton of steel

Lining of tap holes of large-tonnage electric steel melting furnaces

Lining of tap holes of large-tonnage electric steel melting furnaces

Electric melting of intensely colored glasses

Electric melting of intensely colored glasses

Problems in electric melting of glass

The resistivity-temperature characteristics of different glasses were measured. From the relation, a criterion of stability of an electric furnace may be calculated. The release of energy around different electrodes as well as the power density distributions within the glass bath for different electrode-pair configurations are shown. The optimal connections of electrodes from the point of view of minimum energy consumption is described. Theoretical as well as practical problems concerning the corrosion of electrodes are described. Different ways of protecting electrodes against corrosion by glass melts are described. Furnaces for melting different types of glasses and new processes using electricity for melting are mentioned.

Use of gunited coatings for lining the working layer of continuous casting machine tundishes

Under the conditions of the Electric Melt Shop of Belorussian Metallurgical Plant a guniting compound composition has been developed and a production method has been introduced for guniting of the lining of tundishes for casting of cord, cable, and alloy steels.

The quality of refractories for electric ARC steel melting furnaces

An analysis has been made of the physicochemical indices of refractories for lining electric arc steel melting furnaces produced by Magnesite Combine, Zaporozhe, Panteleimonovka, and Semiluki Refractory Plants, Nikitov Dolomite Plant, and Chasov Yar Refractory Combine. It was established that during the period from 1983 to 1987 product quality increased significantly only at Magnesite Combine. The lower quality of the refractories produced by plants of Southern Refractory State Production Union is the result of both the lower quality of raw material used, the state of the technology, and production resources, and the level of mechanization of production operations.

Electric melting in making glass for building and engineering purposes

Electric melting in making glass for building and engineering purposes

Refractories for the slide gates of the steel-teeming ladles of the electric melt shop of belorussian metallurgical plant

The imported refractories and design of the slide gate were analyzed. Experience in their use, which may be used in domestic practice for increasing refractory life and improving the designs of refractories and gates and the method of teeming steel through slide gates, was obtained. At Belorussian Metallurgical Plant a set of domestic refractories has been introduced in the Interstop slide gate in place of the imported ones. The life of the domestic refractories is equal to or exceeds that of the imported analogs.

Some features of electric melting of colorless sodium calcium silicate glasses

Some features of electric melting of colorless sodium calcium silicate glasses

Electric melting of crystal glass

The cost of electricity with respect to gas or oil is high over most of the industrial world, and according to present forecasts, will remain so for at least the next decade. Despite this fact many sectors of the glass producers have turned away from traditional melting methods (utilising gas or oil) and have focused their attention on the use of electricity. The use of electric melting processes has had a particular impact in the field of lead-crystal production. Dramatic changes have occurred as old equipment and even older working practices have had to be abandoned. This revolution, that started with our European partners, has now come to the United Kingdom

Energy comparisons between electric melting and gas firing for the production of rolled glass

The production of glass by electric melting and gas firing is compared on a direct basis. The product and processes are compared from a quality, operational, energy, construction, and economic viewpoint. It is argued that electric melting is much more BTU-efficient but, depending on the cost of local energy, not always cost-efficient. >

Thermal calculation of the water-cooled elements of the lining of an electric arc steel melting furnace

A model and a computer program using it have been developed making it possible to evaluate the influence of the electrical conditions after melt-down in an electric arc steel melting furnace on the thermal operation of tubular water cooled elements of the lining.

A modeling study of flow and heat transfer in an electric melter

A three-dimensional mathematical model was used to calculate flow and heat transfer in electric melting of a flint glass in an industrial scale melter. Calculations were performed for side- and bottom-entering electrodes. Results on rate of heat release, velocity, temperature, and residence time distribution were used to examine the influence of electrode orientation. The residence time distribution was obtained by solving the transient response to a step change in the tracer concentration. The results indicate that the electrode orientation had a significant effect on velocity and temperature distribution, mostly in the planes which contained the electrodes. In these planes it was observed that with the bottom-entering electrodes, the downward glass velocity near the wall was 10 to 20 times larger, but the side-entering electrodes resulted in a more uniform temperature distribution. In planes not containing electrodes, the overall flow pattern and temperature distribution were similar. Both cases were characterized by a high level of mixing and had very similar residence time distributions.

Mechanism of wear of electric arc steel melting furnace wall linings and means of increasing their life

The walls of electric arc steel melting furnaces and especially the region of the slag belt operate under very severe conditions. Together with physicochemical factors the life of the lining is also determined by the design of the refractory shell of the working space of the furnace and the ratio of its primary dimensions.