SU990854A1 - Modifier - Google Patents

Description

(5+) MODIFIER

one

The invention relates to metallurgy and foundry, in particular to the preparation of complex modifiers, and their use for after-furnace treatment of pig iron.

Silicon, calcium, aluminum, carbon, manganese, rum, titanium, and iron, produced on the basis of silicocalcium or ferrosilicon 1, are known and widely used to improve the properties of cast iron containing silicon.

The closest to the proposed technical essence and the achieved result is a modifier 12, containing May,%: Silicon 63.0-80.0 Aluminum 1.3-2.5 Manganese. 0.3-0, Chromium 0.2-0, "

Calcium Carbon 0.1-0.6 Iron Else The disadvantages of this modifier include the fact that it is weak

reduces the gas content of cast iron, has little effect on the improvement of the microstructure and on the reduction in size and shape of graphite inclusions, which leads to inadequate hydro-size of castings and low strength properties of cast iron.

The aim of the invention is to reduce the gas content in the treated iron, reducing the size and

to improve the shape of graphite inclusions, increase the water density of castings and the strength properties of cast iron. The goal is achieved, 5 in that the modifier containing calcium, aluminum, manganese, chromium, carbon, iron and silicon, additionally contains lithium and hafnium in the following ratio of components, 20 wt.%:

Calcium 0.1-3.5 Aluminum 1.0-3.5 Manganese 0.3-5.0 Chrom0.2-8.0

Carbon 0.3-3.2

Iron8.0-25.0

Lithium 0,5-2,0

Hafnium 0.5-1.8

Silicon Else

EXAMPLE In laboratory and pilot conditions, the compositions of the modifiers given in Table 2 are smelted and tested. 1. Properties of the investigated modifiers are given in table. 2

Investigation of the effect of modifiers on the properties of cast iron is carried out by pushing the after-furnace treatment of the original cast iron with the following chemical properties, mash:

Carbon3.23-3.27

 Silicon1.38-1,

Manganese0, 88

Sulfur0.02-0.03

Phosphorus 0.09-0.11

IronErest

For the treatment of cast iron, modifiers of various compositions are used in the amount of 1, 25 + 0.10% of the weight of the liquid cast iron. The temperature of the cast iron is in the range of 1670-1700 K.

The results obtained by changing the properties of processed iron

various formulations of modifiers are given in Table. 3

Presented in table. 3, it can be seen that the use of the modifier of the proposed composition for secondary treatment of cast iron, in comparison with the known modifier, allows to increase the tensile strength from 282-293 MPa, the flexural strength from 56 to 583-606 MPa , deflection boom from 2.9 to 3.1-3 mm, elastic modulus with up to 13 + 50-13800 kgc / mm 10 (, hardness (HB) from 197 to 227-245 kgf / mm (10 Pa) and pressure in which samples begin to sweat, from 102,116 to 3–3,288 PMa. At the same time, a decrease in the total gas content in the iron is observed, the size is reduced and the shape of graphite is improved. inclusions, perlite dispersion increases.

The economic effect is 11.8-12.6 rubles. in the production of 1 ton of usable cast iron castings by increasing the physical and mechanical properties of iron by 1.1-1.3 times and the water density of castings 2.5 times.

Table 1 Melting point. K 1J "90-1510 Manor.

Table 2 1ii50-1i60 lifSS-liyO U50-1 65 l ieo-UyS 1 "55-1 65 1" 60-1 70 86.5-90.585.5-87.5 87.5-89.5 82.5-8., 5 86.0-88.5 82.0-8.5 /.

288

206

56

598 i, 57

2.9 2.8 Modulus of elasticity, kgf / mm IO Pa) 12200 13650 13800

197,232.

Pressure when k282

287

291,284

606,590,588

595

3.1 3.2

3.3 3.1

2 "iO 227 227 230 13700 13500 13600

increase the water density of castings and the strength properties of cast iron; it additionally contains lithium and hafnium in the following ratio of components, masd:

Calcium. 0.1-3.5

ALUMINUM 1.0-3.5

Prolongation of the table.)

45 Sources of information

taken into account in the examination

1, GOST 762-71 Silikokaltsy.

2. GOST TH15-70 Ferrosilicon, Stamps and technical requirements.

Claims (2)

Formula modifier invention for gray cast iron, comprising calcium, aluminum, manganese, chromium, carbon, iron and silicon Nij ^40, characterized in that, in order to reduce the gas content and size of graphite inclusions increase gidroplotnosti castings ,, ^ and strength properties of cast iron, it additionally contains lithium and hafnium in the following ratio of components, May.? Calcium 0.1-3.5 Aluminum 1.0-3.5 50 Manganese 0.3-5.0 Chromium 9,2-8,0 Carbon 0.3-3.2 Iron 8; 0-25,0 Lithium 0.5-2.0 Hafnium 0.5-1.8 Silicon Rest T) information taken into account during the examination ί, GOST 4762-71 Silikokaltsy. 2. GOST 1415-70 Ferrosilicon, Mar ki and technical requirements.