RU1802746C - Clad powder modifier - Google Patents

Abstract

The invention relates to metallurgy. more specifically for out-of-furnace cast iron processing. The clad powder modifier contains a steel shell and a slag-metal filler. The latter consists of magnesium and magnesium chloride at a mass ratio of Mg / MgCl2 0.22 ... 0.28. 1 tab ..

Description

The invention relates to metallurgy, and more particularly to out-of-furnace treatment of cast iron.

An object of the present invention is to increase the degree of refining of cast iron by increasing the adsorption capacity of the modifier. The goal is achieved in that the clad powder modifier, consisting of a metal shell and a slag-metal powder filler, contains 1 magnesium and magnesium chloride in a mass ratio of Mg / MgClz of 0.22 ... 0.28. The mass ratio of MD and MDC12 filler is selected according to the theory of activated slag systems. The metal refining mechanism from harmful impurities (oxygen and waste - x) is presented in the form of the following scheme:

MgCl2- + Mg- Mg2Cl2 (1)

Mg2Cl2 + x - () (2). MgCl2 + Mg + X Mg2xd2: (3)

At a certain temperature, impurity elements in the form of free ions

00

with

(O and S) saturate the bonds of the intermediate complex CI-Mg: Mg-CI, which has two types of chemical bonds - ionic (CI-Mg) and covalent (MD: MD), while the covalent bonds are transformed into ionic: CI - Md: Md - CI + x -

 C - x - Md - CI

The adsorption capacity of this filler is 21.2% sulfur and Mg2SCl2 and 11.8% oxygen in MgaOCb. which is significantly higher than in the known solution (16.4% S and 9.6% .O). Theoretically, with a filler consumption of 1 kg per tonne of pig iron, the sulfur content may decrease by 0.021%, and oxygen by 0.012%.

The patent-licensed search did not establish technical solutions containing magnesium and magnesium chloride

00

oh ke

Xj

N about

with

at a mass ratio of Mg / MgCl2 of 0.22-0.28 and therefore gives reason to believe that the claimed material has significant distinguishing features. The ratio of magnesium and magnesium chloride 0.22-0.28 is due to the fact that if it is above or below this ratio, then the chemical reaction (1) will not completely occur with the formation of an intermediate complex Cl-Mg: MgCI, in which when refined, covalent bonds are transformed into ionic and the adsorption capacity of the modifier becomes maximum.

Implementation of the proposed material: A clad fluffy modifier (flux-cored wire with a diameter of 8.0 mm) containing magnesium and magnesium chloride with different mass ratios (see table) was tested in industrial, conditions of the oxygen-converter shop of Azovstal MK in the mixer section when casting a series of cast iron melts from a mixer into a casting 350-ton bucket. The clad powder modifier was introduced with a tribamer into liquid cast iron at a rate that ensured its required flow rate. When a clad powder modifier was introduced into liquid cast iron With an optimum Mg / MgCla ratio of 0.22-0.28, dust and gas emissions were not observed.

As a result of a pilot test, it was found that the introduction of clad powder modifier with magnesium and magnesium chloride with mass

the ratio of 0.22 ... 0.28 allows you to have the best result in refining action.

Using at Azovstal MK the proposed clad powder modifier with magnesium and magnesium chloride with a ratio of 0.22 ... 0.28 will allow to obtain an economic effect of about 0.64 rub / ton of pig iron by reducing the cost of desulphurization

steel in the converter, during its out-of-furnace treatment. UDM. In addition, the ecologists of the production of high-quality cast iron for responsible steel grades will significantly improve due to the reduction

dust emission.

Claims (1)

SUMMARY OF THE INVENTION Clad powder modifier predominantly for after-furnace treatment of cast iron containing steel a casing and a cinder metal filler, characterized in that, in order to increase the degree of refining of cast iron by increasing the adsorption capacity of the modifier, the filler contains magnesium and magnesium chloride in a mass ratio of 0,, 22 ... 0.28.