SU1315509A1 - Inoculator - Google Patents

Abstract

The invention relates to the field of metallurgy, in particular to the compositions of modifiers used in the technology of producing nodular cast iron. The aim of the invention is to increase the degree of absorption of magnesium and the density of the modifier. The proposed modifier contains, wt%: magnesium 6.0-14.0; copper 10.5-45.0; Nickel 2.0-15.0; silicon 1.5-15.0; chromium 1.0-3.0; cobalt 0.2-0.5; iron else. Additionally, the addition of cobalt to the composition provides for the binding of a part of magnesium to intermetallic compounds. With the proposed ratio of components, the remainder of the magnesium binds in the interplay with copper, nickel, and silicon, which makes it possible to reduce magnesium activity, reduce porosity, increase 2 density and eliminate the pyro effect during smelting and modifier use. (L 2 tabl. CO ate

Description

113

The invention relates to metallurgy and linear production, in particular to modifiers used in the technology of nodular cast iron production.

The aim of the invention is to increase the degree of absorption of magnesium and the density of the modifier.

The proposed modifier contains magnesium, copper, Nickel, silicon, chromium, cobalt and iron in the following ratio of components, wt.%:

Magnesium6.0-14.0

Copper10,5-45,0

Nickel2.0-15.0

Silicon1,5-15,0

Cobalt 0.2-0.5

IronErest

Chrome1.0-3.0

 Impurities: manganese Up to 0.1 The presence of cobalt in the modifier ensures the binding of a part of magnesium to intermetallic compounds. With the above proposed ratio of components, the remainder of the magnesium is bound in the intermetallic compounds with copper, nickel and silicon. In this case, a decrease in the activity of magnesium in the molten modifier is achieved and, as a result, its porosity decreases, its density decreases and the phenomenon of the pyroelectric effect is eliminated with. smelting and modifier application. In this way, conditions are created to increase magnesium utilization. In addition, the proposed modifier has a low cost, since its basis is iron.

When the content of magnesium is more than 14 wt.%, And of copper, nickel, silicon and cobalt, respectively, less than 10, 5, 2.0, 1.5 and O, 2 wt.% In the modifier, the proportion of unbound magnesium increases sharply, which leads to a decrease the degree of its assimilation and pyro effect in the processes of smelting the modifier and the processing of cast iron. Modifier containing 1st less than 6 May. % of the magnesium becomes unprofitable and ineffective, because due to the increased consumption of the treatment, the temperature of the pig iron is excessively reduced.

The upper limits on the content of copper, nickel, silicon, and cobalt (respectively 45.15, 15 and 0.5 wt.%) Are determined by the stoichiometry of the intermetallic compounds with a maximum content of max.

092

and economic considerations. In addition, the silicon content of more than 15 wt.% Leads to a noticeable decrease in the density of the modifier. Maxi-.

The chromium content of chromium (3 wt.%) is limited by its negative effect on the graphitization process in cast iron. The lower limit for chromium and the manganese content are determined by the composition of the cheap raw material for smelting the modifier.

PRI mery Pilot smelting was carried out to evaluate the properties of the proposed modifier. The modifiers are melted in an induction furnace in graphite crucibles with a capacity of 200 kg. In the metal stock, technically pure metals (copper, nickel, magnesium), 75% ferrosilicon, and iron-based complex alloys - industrial ferronickel are used. The course of melting is controlled with the help of thermocouples installed in various places of the crucibles. The modifier is poured into massive steel molds with clamps.

In tab. 1 shows the compositions of the melted modifiers.

Modifiers (Table 1) use

for processing cast iron that is smelted in an induction furnace. It has the following composition, wt.%:

Carbon3,4-3,6

Silicon2,6 - 2,8

Manganese 0.5 - 0.6

Sulfur0.04

Phosphorus 0.02

Iron and impurities Else

The temperature of the cast iron before modifying 1420-1430 C, after treatment 1350-1360 ° C. Modifiers with a piece size of 10-50 mm are placed on the bottom of a conical open bucket

with a capacity of 200 kg of cast iron. The amount of modifier in all swimming trunks is calculated on the basis of an input to cast iron of 0.2 wt.% Magnesium. This takes into account the correction for the degree of absorption of magnesium, which is determined in preliminary experiments and refined in the described melts. Modifiers from above are sprinkled with 75% ferrosilicon and powder crushed to a particle size of 5–15 mm

cryolite in an amount of 1 and 0.1%, respectively, to the mass of iron,

Table 2 presents data on the technological properties of modifiers.

313

The data in Table 2 indicate higher densities (1.5–2 times) of the proposed modifiers and a greater degree of magnesium absorption (1.4–1.9 times) in comparison with the known ones.

Claims (1)

The proposed modifier is recommended for industrial use in the production of Responsible castings from high-strength cast iron with graphite graphite., Invention Modifier containing magnesium, copper, nickel, silicon, chromium and jelly Magnesium Copper Nickel Cobalt Chromium Silicon Manganese Fluorides of rare earth metals Iron Silicocalcium 6,07,69,010,812,014,03,010,0 10,522,821,329,035,845,010,00,1 15.0.13.09.914.62.42.0O, 0 0.20,250.3 0,250,40,5 2.03.01.2 1.11.01.00.110.0 13,815,014,613,76,01,5 V silicocalcium 0,070,090,070,090,080,0610,00,1 ----- - 15.0 0.1 Ostap-Os-Os-Osta-Ostap-1,010,0 nye talny-talny ny - - - - - Rest - Rest 5509 4 30, characterized in that, in order to increase the degree of absorption of magnesium and the density of the modifier, it additionally contains cobalt in the following ratio, wt.%: Magnesium Copper Nickel Silicon Chromium Cobalt Iron 6.0-14.0f 10.5-45.0 2.0-15.0 1.5-15.0 1.0-3.0 0.2-0.5 Else Table 1 Density, g / cm 7.2 6.9 7.0 6.7 7.3 7.1 3.6 4.6 4.5 Degree of learning Mg,% 0.53 0.57 0.52 0.54 0.52 0.49 0.30 0.35 table 2