SU1588793A1 - Alloying composition for pig iron - Google Patents

Abstract

The invention relates to metallurgy, namely to compositions of master alloys and can be used to produce high-quality pig iron operating under water hammer conditions. The purpose of the invention is to increase the hydraulic strength and tightness of cast iron. The ligature contains components in the following ratio, wt.%: Tin 7-9

lead 1-4

zinc 0.5-3

nickel 10-16

cerium 5-7

lanthanum 2.5-4

copper else. 1 tab.

Description

The invention relates to metallurgy, namely to compositions of master alloys and can be used in the manufacture of engineering castings operating under cyclic and hydraulic loads.

The purpose of the invention is to increase the cyclic hydrostrength of the tightness of cast iron.

The invention is illustrated by the following example.

The master composition of the proposed composition is prepared by melting tin bronze waste in an induction furnace and adding nickel and ferroceri to the melt, taking into account the 95% nickel uptake, cerium and lanthanum 80-95%. The ligature was introduced into the liquid alloy at 1300-. The mastering of the components of the ligature is from 80 to 95%. The amount of ligature introduced into the melt was 1.0%.

The test piece for leaktightness and cyclic hydrostrength is a disc with a diameter of 50 mm and a thickness of 4 ± 0.5 mm. In the central

of the sample is a cylindrical recess with a diameter of 25 mm to a depth, providing a working part thickness of 2.0 + 0.05 mm. Tightness was determined by the formula .35

where P is the fluid pressure;

W is the wall area;

t is the time of leakage of fluid;

Q is the amount of leaked fluid;

 - fluid viscosity. Tests for tightness and cyclic hydraulic strength were carried out. On the hydrostand, the working fluid is kerosene. The working pressure for testing the sample was 300 kg / cm.

Cyclic leak tests were carried out by increasing the pressure to 100 kg / cm and removing it to zero on samples of the same design. The criterion for inducing tightness was the number of cycles prior to its mechanical scattering.

with "

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00 00

vj

wed

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The test results are presented in the table.

As can be seen from the table, the use of ligatures of the proposed chemical composition significantly improves the properties of cast iron,.

The limits of tin, nickel, lead, and zinc content were 7–10%, 10–15%, 1–5%, 0.5–3%, respectively, chosen to ensure maximum hardening of the metal base with a minimum degree of doping. An increase in tin of more than 10% and nickel more than 15% does not give a significant increase in the cyclic hydrostrength of pig iron. An increase in the ligature composition of lead by more than 5% leads to the formation of lead-containing eutectics, which reduces the hydraulic strength of cast iron, an increase in zinc by more than 3% significantly reduces the percentage of its absorption when introduced into the liquid melt due to intensive burning.

The role of cerium and lanthanum is reduced to an increase in the hydraulic strength and tightness of cast iron by grinding and a more even distribution in the structure of graphite inclusions, as well as by catching the dispersion of primary particles.

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five

ren. Combined input of cerium and lanthanum has a more effective effect on the structure than the influence of a separate element C1 or La, taken even more. The total content of cerium and lanthanum should not

I exceed 11%. When 1% of the master alloy containing more than 11% of C1 and La is introduced into the melt, deterioration of the properties of cast iron is observed.

Claims (1)

Invention Formula The ligature for cast iron, containing tin, lead, copper, o-tl and h, is that with the aim of increasing the cyclic hydrostatic strength and tightness of the iron, it additionally contains nickel, zinc, cerium, lanthanum in the following ratio, wt.%: Tin 7-9 Lead 1-4 Nickel 10-16 Zinc 0.5-3 Cerium5-7 Lanthanum2,5-4 CopperE rest Compiled by I. Bekrenyova Editor M. Nedoluzhenko Tehred L. Serdyukova Corrector M. Pojo Order 2517 Circulation 483 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 Subscription