SU697590A1 - Cast iron modifier - Google Patents

Description

(54) MODIFIER FOR CAST IRON

one

The invention relates to ferrous metallurgy, in particular to complex modifiers for the production of pig iron with high physicomechanical properties.

Known modifier for cast iron of the following composition, wt.%:

Silicon30-60

ManganeseUp to 15

Potassium and BariumDo 15

Cerium, lanthanum, niobium, tantalum, vanadium, zirconium, aluminum, boron (at least 4 electrolytes) 20-40

Iron Else 1

The disadvantages of the known modifier -low efficiency, poor physical and mechanical properties of the modified iron and chill thin-walled castings.

The closest to the described

The invention, by its technical essence and effect achieved, is a modifier for cast iron, containing wt.%:

Calcium6-14

Barium10-15

Rare earth

metals6-8

1-5 0.1-3.0

1-20 0.5-6.0

5-10

2 Else

A disadvantage of the known modifier is the low strength of the modified cast iron, which is 50 to 54 kg / mm when stretched.

The aim of the invention is to increase the strength of cast iron during modification.

In order to achieve the goal, the proposed modifier for -chugun containing calcium, barium, rare earth metals, zirconium, silver, iron, carbon and silicon, additionally contains magnesium in the following ratio of components, Bec.% T

25

697.590

, Magnesium as a part of the modifier allows to obtain a spherical, lamellar and vermicular form of graphite in the iron. It is a strong deoxidizing, desulphurizing and iron degasser. The bubbling of the metal, caused by magnesium vapors, contributes to the uniform distribution of the components of the modifier, which improves the physicomechanical properties of the cast iron, in particular its strength.

Example. Cast iron containing. 85 11 1.0 Remaining 65.65 6 15 nue 7 1 3 10 0.5 Other 8 10 12 nue 67.210 14 10 6 3 0.1 20 6.0 The rest 65.4 total calcium, barium. Rare-earth metals, zirconium, aluminum, iron, carbon, and silicon, are distinguished by and with the fact that, in order to increase the strength of cast iron, it additionally contains magnesium in the following ratio of components, wt.%:

; /, 1weight,%: carbon 3.8; silicon 2.2; manganese 0.6; chromium 0.065 sulfur 0.05; phosphorus 0.085, iron - the rest, melted in an induction furnace and modified with a modifier by immersing it before putting the iron on the bottom of the ladle. The amount of modifier introduced is 1.5% of the weight of molten iron.

The table shows the composition of the modifier and the properties of the modified cast iron.

255

269

255

Sources of information taken into account in the examination

1, US Patent No. 3383202, cl. 75-122,1968.

2. USSR author's certificate according to application number 2627079 / 22-02,

cl. C 22 C 35/00, 12.06.78. 66.0 3.4-3.6 2.8 68.0 3.2 2.6-2.8 66.8 3.2-3.4 2.6