SU1366545A1 - Inoculant - Google Patents

Abstract

FIELD OF THE INVENTION The invention relates to the field of foundry, in particular, for the production of high-strength cast iron, mainly for massive castings. The aim of the invention is to increase the perlitization of a metal base in a cast state and to reduce the high mechanical properties of cast iron in large massive castings with a wall thickness of 150 mm or more. The proposed modifier contains, wt%: magnesium 6–9, calcium 0.1–4, barium 0.1–4, rare earth metals 0.1–4, copper 10–50, zirconium 1–20, molybdenum 0.1– 10, antimony 0.1-5, iron 1-15, manganese 1-20, boron 0.1-4, nitrogen 0.1-3, silicon, the rest. The use of the proposed modifier is effective in obtaining massive castings with a wall thickness of 150 mm or more, table 2. S (l

Description

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The invention relates to foundry and can be used to produce high-strength cast iron mainly for massive castings.

The purpose of the invention is to increase the perolization of the metal base in the cast state and to preserve the high mechanical properties of the cast iron in large massive castings with a wall thickness of 50 mm or more.

The modifier of the proposed composition contains 5 wt.%

Magnesium 6-9

Capes: s About 31 - 4

Barium OJ - 4

Rare earth

metals About j1 - 4

Copper .10-50

Circoh-shy About j 1 - 20

Molybdenum O 91 - 10

Antimony Oji 5

Iron 1 15

Manganese 1 -. 20

Bor0.1 - 4

Nitrogen Oj 1 .- 3

Silicon Rest

The introduction of manganese boron and nitrogen into the complex modifier contributes to the perlction of the metallic cast iron base in massive castings c. wall thickness of more than 150 pp

When a manganese modifier is introduced into the composition of less than 1%, its effect on obtaining the pearlite structure in massive castings does not appear. The introduction of more than 25% manganese to the modifier causes the formation of carbides in the cast structure of cast iron, which leads to a decrease in the strength of the modified cast iron in massive castings.

When a modifier is introduced into the composition less than boron, the amount of ferrite in the structure increases and the strength of cast iron decreases. Entering into the composition of the modifier of boron more than 4% causes the formation of carbides o

The amount of 051-3% in the nitrogen modifier composition, together with manganese and boron additives, contributes to the perlithization of pig iron in massive castings. When a modifier is introduced with less than 0.1% nitrogen, its effect on cast iron casting does not appear. nitrogen in the modifier in an amount of more than 3% results in casting with chill.

especially when boron and antimony are simultaneously introduced into the cast iron

The reduction in the proposed component of the modifier of such strongly graphitizing elements as calcium and barium; up to 4% instead of 5-15% in a known composition helps to reduce the amount of ferrite in massive castings with a wall thickness of 150 mm and more. With a content of more than 4% calcium and more than 4% barium, a ferrite-pearlite structure is obtained with a significant amount of ferrite (up to 25%). In addition, calcium, barium and rare-earth metals together with magnesium are spheroidizing elements. Their combined input allows to obtain a spherical shape of graphite in

thick-walled massive castings even in the presence of demodifying elements (mouse, titanium, and other elements) When the content of the modifier is less. 0.1% calcium,

bari and rare-earth metals their spheroidizing effect is not manifested, respectively, the mechanical properties of cast iron deteriorate

The presence of the modifier

magnesium in the amount of 6–9% and rare earth metals in the amount of 0.1–4% together with barium and calcium causes the formation of nodular graphite in the iron. When the modifier contains less than 6% magnesium and less than Ojl% REM in thick-walled massive castings, lamellar graphito forms at a content of more than 9% magnesium and more than 4% REM in the modifier

Carbium appears in the cast iron structure. dies that reduce the mechanical properties of castings

Such alloying elements in the composition of the modifier, such as copper in the amount of 10-50%, zirconium in the amount of 0.1-20%, molybdenum in the amount of 0.1-10%, antimony in the amount of 0.1-5%, are elements perlite the metallic base

cast iron in massive castings When the modifier contains less than 10% copper and less than 0.1% zirconium, molybdenum, and antimony, their effect on the perlithization of cast iron in massive castings is not

a significant amount of ferrite is formed in the cast iron structure. When the modifier contains more than 20% zirconium, more than 10% molybdenum and more than 5% antimony in the structure

cast iron carbides appear, dramatically reducing its mechanical properties.

Entering more than 50% copper into the modifier is not economically viable.

Example The smelting of the proposed modifier was carried out in an induction furnace Mni-J02 with a capacity of 100 kg. The charge materials used were ferrosilicon FS75 silico-calcium SKZO, ferrosilicon with REM FS ZORZShO, silico barium with 40% barium, silico zirconium with 50% zirconium, ferro-manganese Fmp75, 30% 30% 30% barium, silico barium with 50% barium, silico zirconium with 50% zirconium, ferromanganese FMPr, 15%, 15%, 30% 30% barium; 60% molybdenum, M4 copper, SuOO antimony with 98.8% antimony, TSF ferroboron with 20% B, nitrogenous ferromanganese with 14% nitrogen, metallic magnesium. Download

65.5

wt.%: carbon 3.6, silicon 1.6, manganese 0.6, chromium 0.15 phosphorus 0.03, sulfur 0.03.

Original cast iron was melted in arc

howling DSP-0.5o electric furnace

The temperature of the cast iron during the modification was 1400-1420 ° C. The modification was carried out by plating the modifier to the bottom of the ladle and then pouring the cast iron. The amount of the modifier introduced was 1.5% of the mass of the liquid iron. To study the structure and

15 properties of the modified cast iron were washed down with massive samples with a size of mm and a size of 250,250 X300 mm. The mechanical properties and structure of the cast iron were determined on the mill.

The charge materials were carried out in single-piece samples cut from the next sequence: at the bottom of the front of the cast samples

chi was loaded with ferrosilicon, silico-calcium, silico-zirconium, ferromanganese, ferromolybdenum, copper, and ferroboron. Then, after melting in order to reduce the burnout, the silicobarium, ferrosilicon with rare earth metals,

25 Modified with different ratios of the components of the proposed composition, as well as composition 9 (known), were melted and tested.

When the content of the modi

antimony and nitrogenous manganese. Lastly after melting

of all charge materials compulsory for the KOR of elements corresponding to metal on the rod but

The proposed composition (composition 1 of cast iron in massive otlich-samples corresponds to perlite-ferritic with an insignificant amount of ferrite (4-8%) and by enhanced mechanical properties. When the content content of the modifier exceeds the upper and lower limits (composition 4, 5, 6, 7) the structure of the modified cast iron varies: increasing with the amount of ferrite, cementite appears. Accordingly, the content of pearlite changes, the mechanical properties of the cast iron change.

magnesium,

The composition of the charge (n kg:

Ferr about silicon

FS75

Silikokaltsy SKZA

Silicobarium

Ferrosilicon

with RMZ FSZO

REMO

Silikocyrconium

Ferromanganese

Mfmp75

Ferromolybdenum FMO

Copper M4

Antimony suoo

Ferrobor OBO

Nitrous

ferromanganese

Metal

magnesium

The compositions of the vyplavlrov presented in the effectiveness of the model on the composition of the pig

The mechanical properties and microstructure of the modified iron are given in table 2.

25 Smelted and tested modifiers with different ratios of the components of the proposed composition, as well as composition 9 (known).

When the content of the modified.

About kator elements

five

0

6

0

In the proposed composition (compounds 13), the structure of cast iron in massive castings-samples corresponds to perlite-ferritic with an insignificant amount of ferrite (4-8%) and by improved mechanical properties. When the content of the modifier components exceeds the upper and lower limits (compositions 4, 5, 6 , 7) the structure of the modified cast iron changes: the amount of ferrite increases, cementite appears. The content of pearlite changes accordingly, the mechanical properties of the cast iron change.

t

When aluminum, tin, and carbon (composition 8) are present in the composition of the modifier, the amount of ferrite in the structure increases, the amount of pearlite decreases accordingly.

The use of the proposed composition of cast iron showed the effectiveness of introducing a modifier of boron, nitrogen and manganese into the composition when casting massive castings with a wall thickness of 150 mm or more in order to increase the structure perlite and preserve high physical and mechanical properties of cast iron.

Samples of size 150x150x200 mm

3.4 3.6 3.6 3.8 3.4

3.3 1.6

1, A

Perlite-ferritna, ferrite up to 6% Perlite-ferritna, ferrite up to 8% Perlite-ferritna, ferrite up to 6% Perlite-ferritna, ferrite up to 4%,

cementite to

Oba size 250 250 300 mm 3.2

3.0

3.0

3.0

3.0

2.8 1.8 2.0

2.4 2.6 3.4 3.4

Table 2 lending

50 300 mm

277

271

274 310

262

239

Perlite-ferritna, ferrite up to 10% Ferrito-perlitna, ferrite up to 50% Perlite-ferritna, ferrite up to 4%, cementite up to 10% Perlite-ferritna, ferrite up to 12% Perlite-ferritna, ferrite up to 30%

Perlite-ferritna, ferrite up to 10% Perlite-ferritna, ferrite up to 15%

Perlite-ferritna,

ferrite up to 12%

Perlite-ferritna, ferrite up to 4%, cementite up to 6% Perlite-ferritna, ferrite up to 15% Perlite-ferritna, ferrite up to 50%

1366545

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Mechanical properties of modified cast iron

Strength, NPA

 726,724

.-- rt

680 690 648 636

Relative extension %

. 1.2

2.8 3.0 2.6 2.4

Tverdos NV

ZSH

261

244

10 Continued table. 2

Cast iron structure

Hardness, HB

Perlite-ferritna, ferrite up to 5%, cementite up to 8% Perlite-ferritna, ferrite up to 15% Perlite-ferritna, ferrite up to 40%

Claims (1)

1366545. Formula of the invention Modifier mainly for Magnesium Calcium 6-9 0,1 - 4 iron castings containing mag Barium 0,1 - 4 niy, calcium, barium, rare earth ₅ Rare earth metals, copper, zirconium, molybdenum, metals 0,1 - 4 antimony, silicon and iron, excellent Copper 10 - 50 pretending to Zirconium 0,1 - 20 increase perlitization of metal Molybdenum 0,1 - 10 foundations in a cast condition and preserve Antimony 0.1-5 high mechanical properties of cast iron Iron 1 - 15 on in large massive Manganese 1-20 shedding with a wall thickness of 150 mm and Boron 0,1 - 4 more, it additionally contains mar- Nitrogen 0,1 - 3 Ghanaian, boron and nitrogen in the following Silicon Rest wearing components, wt. ₀ %: