SU969761A1 - Method and electrolyte for decarburizing steel - Google Patents

Description

The invention relates to metallurgy, in particular to methods for the decarburization of steel, and can be found in the manufacture of transformer steel.

The known method 1 chemical-heat treatment of steel during the anodic process in the electrolyte is as follows. the composition, vol.%:

Nitric acid 5-10

Chloride. Aluminum aluminum 5-15. Glycerin 10-15

Waterspout

The known electrolyte is designed to saturate the steel with carbon and nitrogen (cyanidation).

The closest in technical essence and the achieved result to the proposed method is the decarburization of steel, including the treatment with a constant electric current in an aqueous solution of soda. The method provides for the decarburization of steel to 0.017 wt.% Carbon 2.

The disadvantage of this method is that pulsed arc discharges lead to current instability, electrical erosion and burns of the product. A significant disadvantage is also the fact that only the distribution of the carbon content in the steel is actually carried out, and not the decarburization. While the surface layer is 0.2 mm thick, the carbon content increases, while in the deeper one it decreases. With the known method, erosion craters with an average depth of 10–15 µm exist on the surface of the product, reaching 10 ha at a specified time of a surface density of 100 mm2. Prizhogi are occasionally observed. In this case, the amplitude of current oscillations reaches 1 A / cm, their frequency is 5-15 kHz, which

15 due to the occurrence of pulsed arc discharges.

The purpose of the invention is to eliminate erosion and burns, increasing the degree of decarburization.

20

This goal is achieved by the fact that, according to the CTAfti decarburization method, which involves the treatment with a direct electric current in an aqueous electrolyte solution, the treatment is carried out during the anodic process.

In this case, the method can be carried out in an aqueous solution of ammonium chloride at the following ratio of components, wt.%:

Ammonium Chloride 4-6 Water, Ostygshnoe. EXAMPLE (Steel was decarburized (voltage 180 V, current density 1 A / cm, practically without hesitation, sample temperature) containing radioactive

11THEOP of carbon - 14, which is previously introduced by diffusion saturation. Burns and craters are absent.

Result ylayer radiometric analysis are given in the table.

Ammonium Chloride5 2 Water - Hot5

Ammonium chloride, b 5 Water - the rest

Ammonium Chloride4 5

1 Treatment in a 15% water solution of soda during the cathode process for 2 minutes, sample temperature 700 ° C, voltage 180 V, current density 2.5 A / cm with an amplitude of pulsations up to 1 A / cm leads to the following redistribution carbon;

On the surface - a fivefold increase. At a depth

Claims (2)

0.1 mm - without changes 0.2 mm - a decrease of 30%; 0.4 mm - a decrease of 16%; 0.8 mm - a decrease in LD, 1%. The results show that the termination of the anodic process in an aqueous solution of ammonium chloride leads to the elimination of erosion and burns and the removal of carbon from the surface layer. In addition, the power consumption is reduced by more than 2 times. Claim 1. Steel decarburization process, including treatment with a constant 28104 62423530 60403530 60403225 an electric current in an aqueous electrolyte solution, characterized in that, in order to eliminate erosion and burns, to increase the degree of decarburization, the treatment is carried out during an anodic process. 2. Electrolyte for decarburizing steel containing water, characterized in that, in order to eliminate erosion and burns, to increase the degree of decarburization, it additionally contains ammonium chloride in the following ratio of components, wt.%: Ammonium Chloride 4-6 WaterEverything Sources of information taken into account in the examination 1. Author's certificate of the USSR W 461161, cl. C 23 C 9/10, 1975., 2. USSR author's certificate number 502963, cl. C 21 D 8/12, 1974 /