SU777075A1 - Master alloy - Google Patents

Description

one

The invention relates to metallurgy, in particular to the search for high-performance ligatures for iron-carbon alloys. Known ligature of the following composition, wt. %:

Cerium10-13

Vanadium23-25

Aluminum3-5

Silicon 23-25

Iron Else 1

Significant disadvantages of the known ligature are the low digestibility of cerium and vanadium and the relatively low casting and mechanical properties of the steel being processed.

The purpose of the invention is to improve the assimilation of components during alloying and to increase the casting and mechanical properties of the steel being processed.

This goal is achieved by the fact that the proposed master alloy containing vanadium, rare earth metals, aluminum, additionally includes calcium and nickel in the following ratio of components, weight. %:

Vanadium5-30

Rare earth metals 10-30

V-t-j Sv-; J r-- f4 f w

(54) LIGATURE

 e; EE-p G | And I

Aluminum5-30

Calcium10-15

Nickel15-50 Ligature contains the following 5 impurities:

Silicon 1-3

Iron1-5

The additional introduction of nickel to the composition of the alloys is associated with an increase in its specific gravity, which ensures a faster immersion in the steel being processed and, accordingly, minimal burning out of rare earth metals (REM),

15 calcium and vanadium. This provides a more complete assimilation of these elements and an increase in the entire complex of casting and mechanical properties of steel. In addition, nickel forms with REM a series of intermetallic compounds having a low melting point, which is also beneficial.

The introduction of calcium ligatures is explained not only by its deoxidizing and refining ability, but also by its globular effect on non-metallic inclusions. The multiphase inclusions formed during the introduction of calcium are more accurately removed from the liquid steel by reducing their specific gravity, and the remaining inclusions acquire the correct large shape and are disorientedly distributed in the modified steel. These factors contribute to improving the casting and mechanical properties of steel.

Example. The proposed and known ligatures were used in the smelting of steel 45L and 5ХНМЛ.

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

Table 1

The metal was smelted in a 7-ton electric-arc furnace (45L) and a 300-pound induction furnace (5ХНМЛ) according to the current technology. Experimental compositions of the ligature was introduced into the liquid steel when discharged from the furnace into a 7-tonne pouring ladle (45L) and in the process of fractional casting from a 300-kilogram furnace into L 00-kilogram bucket (5XHML). In order to compare the effectiveness of the effect of the experimental ligature on the properties

of the melted steel, part of the melts was modified with a known ligature. Experimental compositions of the ligatures were administered in the same amount of 0.3 weight. % by calculation.

The degree of assimilation of calcium, rare-earth metals and vanadium in modified steel, a complex of casting and mechanical properties was investigated.

The research results are summarized in table. 2

table 2

Claims (1)

Invention Formula The master alloy containing vanadium, rare earth metals, aluminum, characterized in that, in order to improve the absorption of the components — when doped, to increase the casting and mechanical properties of steel — it additionally contains calcium and nickel in the following ratio of components, weight. %: Vanadium5-30 Rare earth metals 10-30 Aluminum5-30 Calcium10-15 Nickel15-50 Sources of information taken into account in the examination 1. USSR author's certificate 558959, cl. C 22 C 35/00, 1977. ten