SU449937A1 - Method of smelting metals and alloys - Google Patents

Description

(54) METHOD OF MELTING METALS AND ALLOYS

one

This invention relates to the field of metallurgy.

There is a method of smelting metals and alloys, including the filling of the charge, melting, fine-tuning, production and casting of metal with a supply to the metal in the process of melting electric current. However, the implementation of a known method in the industry is hindered by the need for ultrasonic treatment of the molten metal. This especially applies to the processing of metal melts at high temperatures, for which reliable materials for emitting ultrasonic vibrations are still unknown. However, passing an electric current in a closed circuit through a melt without ultrasound gives no effect.

In order to change the gas content of the proposed Method, the gas phase is supplied with a current of opposite polarity as compared to the current supplied to the metal, and the electrostatic field is maintained within 10-600 V and is limited by spark discharge.

When current is applied to the metal and the electrode, a potential difference is created at the metal-gas interface, which affects the solubility of gases in the first surface layer. Gases as surface-active elements, having a high solubility in the surface layer and being in ionic form, charge the surface layer. The electrical character of surface phenomena allows them to be influenced by the application of an electric field. The applied electric field changes the diffusion

mobility of gases in the boundary layer of the metal melt due to recharging of diffusible gas particles. With the loss of electrons, hydrogen reduces its size by about 700 times, nitrogen - 16, oxygen - 16. This affects their diffusion and affects the flow of gas exchange processes at the metal-gas interface.

Example. The test of the influence of the growing electric field from 10-600 V

on iron-carbon alloys: cast iron and steel x when they are melted down in vacuum, helium and nitrogen. In the Tamman furnace, three samples of the same composition and mass are present at the same time: “a witness and an experienced one, one with a negative,

and the other with a positive surface charge. For an hour, a current of 50 mA / cm is passed through the charged metal and the gas layer. In order to eliminate the possible effect of various overheatings, the same current is passed through the witness in a closed circuit. A comparison of the microstructures and the gas content shows the effect of the electrical thickness. When smelting in nitrogen, a positive charge on the surface of a MSt5 steel sample increases the nitrogen content in the metal to 60%, reduces oxygen to 40% and hydrogen up to 40% compared to a witness, a negative charge on the surface of the sample increases the nitrogen content in the metal to 20%, reduces oxygen is up to 30% and has little effect on hydrogen. 4 Subject of the Invention The method of smelting metals and alloys, including charging of the charge, melting, finishing, and pouring and pouring the metal to the metal during the electric current melting process, is characterized in that, in order to change the gas content, the opposite is applied to the gas phase polarity compared to the current supplied to the metal, and the voltage of the electrostatic field is maintained within 10-600 V and limited to spark gas discharge.