SU648328A1 - Exothermal slag-forming composition for teeming metal - Google Patents

Description

Stable casting concentrate 5, O-1O, O

Oxides of rare-earth metals20.0-30.0

Slag blast furnaces Else.

In order to mix the mixture, all the entrances to its composition must be dry and crushed to a fraction of more than 2 mm, and then shredded nepfeii-. mixed with oxides repocamel metals (REM).

The mixture can be applied in powder form, in the form of granules with a fraction of 5-15 mm or briquettes, which are poured into a mold before pouring molten steel. The mixture consumption is 5-8 kg / ton steel. With the use of a ventilating slag-forming mixture according to the invention, it is possible to use L11Bb (1g alloyed and high-quality carbon steels.

The modifying affect of the agrothermal slag-forming mixture is achieved by considering that the rare-earth metals (especially in combination with the iron oxides of the mixture) are the centers of the formation of the steel, and also due to the modifying effect of the rare-earth metals themselves, which are partly formed when aluminum is reduced from their oxides.

, In the composition of the mixture according to the invention, a staurolite concentrate of the following composition is used,%: AC O 48-50} SiOg 26-28; 14-16; 2pO2 11, 5; TiO 0.6-1.5; CaO + MgO 0.5.

Granulated blast furnace blast furnaces in accordance with GOST 3476-60.

Oxides of rare-earth elements {CeO, j,,, Pr2, O) with fraction O, O8 mm or less.

Ingredients

648328

Under industrial conditions, casting of steel from above was tested using the proposed exothermic slag-forming mixture.

The lower limits on the content in the mixture of staurolite concentrate and rare-earth metals oxides are chosen, based on obtaining the minimum and maximum modifying effect.

The compositions of the mixtures are given in table. one.

Physical and chemical properties of the mixtures are given in table. 2

The melting point of the Slag from the mixtures listed in Table 1 was determined on a MH-02 high-temperature microscope, the viscosity on an electrophobic viscometer, and the surface tension on the method of a lying drop. Viscosity and surface tension were determined at temperatures of the cast metal -.

During the casting of the experimental steel ingots, the goodness of the ingots and an increase of 10-15% in mechanical properties were obtained, in particular by impacting viscosity at elevated temperatures and after stopping, along with a reduction in the rejection of finished steel from surface defects by 1 - 2%.

Characteristics of casting ingots are given in Table. 3,

As a result of the study of the experimental J metal, it was also found that the natural and actual grain of the metal treated with mixtures of rare earth metals is 1-2 points smaller, nonmetallic inclusions are less deformable and their content is lower regardless of which rare earth metals was in the mixture .

Table 1

The compositions of the mixtures, weight. %

A mixture of oxides of rare-earth metals: CeO 2O-25%, 2025%, 22-25%, PrjOg 8-10%, U2Oz5-8%, the rest - oxides of other rare-earth elements.

Properties

Viscosity, P S

Surface tension, er g / cm

Melting temperature, ° С

Note: In the numerator, the limits of the oscillations are shown in vxx; in the denominator, its mean values are in the denominator.

Claims (1)

Formula isbret and Exothermic slag-forming mixture for metal casting, including; apiumium, manganese ore, silicate lump, blast furnace slags, staurolite concentrate, which, in order to improve the quality and mechanical characteristics of the metal, modify in the process of casting and solidification, and the mixture additionally contains oxides of rare-earth metals with the following ratio of ingredients, weight. %: Aluminum15.0-20.0 Manganese Ore10.0-15.0 table 2 -f. „. Mixtures 9D 7.7 11.0 Silicate clump 15.0-20.0 Staurolite con5, 0-10.0 centrate Oxides of rare-earth20, 0-30.0 Sulfur metals Slag-domain peat, whose Sources of information taken into account in the examination . USSR author's certificate No. 428853, cl. On 22 L 27/06, 1972, 2, USSR Author's Certificate No. 495152, cl. B 22/10/1974.