SU863698A1 - Modifier - Google Patents

Description

(54) MODIFI1SATOR

The invention relates to ferrous metallurgy, in particular to complex alloys for modifying pig iron on. Known mssdifikator for cast iron following composition, wt.%: Calcium silicon 3.5-6.5 Magnesium Р ed coemel 10, 5-16,5 nes metals Else Iron The disadvantage of the mopificator is that it modifies vyrvH in its structure a large amount of cementite, therefore, castings must be subjected to prolonged heat treatment. The aim of the invention is to reduce chill and increase the ductility of pig iron. The delivered pellet is achieved by the fact that the modifier, containing cr & calcium calcium, magnesium, rare-earth bales, and iron, additionally contains barium and stronium at the following component ratio, wt.%: Silicon 47-60 Calcium 3-7 magnesium 3.5-6, 5 Low-energy metals 12.5-17.5 Barium5.2-10.5 Strontium 3.5-7.0 Iron Rest Table. 1 shows the composition of the produced modi (ikatorov. Modifiers are introduced into synthetic cast iron in an amount of 1.5%. Castings of high-strength cast iron with spherical granite with a diameter of 20.50 and 100 mm are obtained. The microstructure, mechanical properties and shape of graphite of cast iron castings are not heat treated, B; Table 2. As can be seen from Table 2, castings with a cross-section of 50 mm and above of experimental variants 1-3 have a slight degree of chill off with a good cross section of strength and plastic properties, and casting of all sections of the known variant to eliminate chill heat treatment.To establish the heat treatment mode, samples with a cross section of ft 20 ml are subjected to normalization annealing; heating for 3 hours to 950 ° C, holding in an oven and cooling in air. Depending on the duration of exposure of the samples heated in the furnace up to 950 ° C, 3 j modes are carried out; Thermal processing t shutter speed 1 h (), shutter speed 3 h (b), shutter speed 6 h (S).

In tab. 3 shows the characteristics of the shape of the graphite, the microstructure and the mechanical properties of the castings of 1–20 mm. After heat treatment.

6.5

60

7

5.1

53.5 4.9 47 54.2 3.5 3 5.6 5.3

20 70 80

20 50 100

Prototype

As can be seen from the table. 3, after heat treatment of castings of 0–20 mm, even with an exposure of 1 hour in all samples of the experimental modification options, there is no cementite in the metal microstructure, while after 6 hours of exposure in the furnace of a known modifier, up to 2% of cementite remains in the metal microstructure.

Table 1;

3.5

5.2

The rest 5.2 7.8 the same 7.0 The same

10, b Same

table 2

310

Gr. No. 310 Same 293 SHG-1

80

, T a b l and u a 3

Claims (1)

Claim A modifier containing silicon, calcium, magnesium, rare earth metals and iron, characterized in that, in order to reduce the removal and increase the ductility of cast iron, 40 it additionally contains barium and strontium in the following ratio of components, wt.%: Silicon 47-60 Calcium 3-7 Magnesium 3.5-6.5 Bulk metals 12.5-17.5 Barium 5.2-10.5 Strontium 3.5-7.0 Iron Else