SU739123A1 - Modifier - Google Patents

Description

I

This invention relates to metallurgy of alloys, namely, modifiers for high-strength nodular cast irons used in the manufacture of wear-resistant parts subjected to dynamic loads, for example piston rings.

Known modifier tH the following composition, wt.%:

Copper0,1-10

Nickel0,1-20 th

Manganese 0.1-10

Magnesium3.0-10

Chrome

Iron1,0-10

Rare earth fluorides

metals .0,1-15

SilikokaltsiyEmost

The known modifier has drawbacks that make its use difficult and do not allow to obtain sufficiently high wear resistance and dynamic strength in the production of thin-walled parts, such as piston rings, since the presence of chromium leads

to an increase in rejection of the structure due to the appearance of inclusions of lamellar graphite and structural cement (bleached). The use of rare-earth metals in the form of fluorides worsens the working conditions of the personnel due to the release of harmful substances when the modifier is introduced into the cast iron. I H3Koe content of copper and nickel does not provide sufficient wear resistance and durability and does not meet the chemical composition requirements for H1X parts. .

The purpose of the invention is to simplify the process of melting and increase the physical and mechanical properties of high-strength nodular cast iron.

This goal is achieved in that a modifier containing copper, nickel, manganese, mass, calcium, silicon; iron and rare-earth metals without fluorides additionally yttrium is added, with the following ratio of components, wt.%:.

Copper 20-50

Nickel20-40

Manganese 0.1-10 Magnesium 0.1-10 Calcium 0.1-1-10 Silicon 0.5-10 Rare earth metals 0.1-10 Yttrium 0.1-10 Iron Other. moreover, the total number of Magsh and Yttri must be at least 4.0%. Yttrium contributes to the suferoidization of graphite and alloys the metal base, due to which the physicomechanical properties of the produced iron are improved, the scrap in the microstructure is reduced, and the reliability of the parts increases. In tab. 1 shows the physico-mechanical properties of piston rings made of serial high-strength cast iron (HF) and HF with the proposed modifier.

Serial high strength

cast iron (HF) 15700-16300

.HF received by use; for the modifier 17010-18100

Example. The modifier is prepared by IB high-frequency induction furnace LP-67 with a graphite crucible. Pure metals and ferroalloys are used as starting materials.

The modifier is used to obtain norshne rings of high-strength cast iron of the following chemical composition, wt.%:. Carbon 3,4-3,9

Silicon3,1-3,4

Manganese 0.2-0.4

Phosphorus 0.12-0.14

Sulfur0,018-0,021

Copper 0.60-0.82

 Nickel0.65-0.75

Magnesium0.004-0.05

Calcium, 0.002-a, 025

РЗМ0,03-0,08

Yttrium0,005-0,042

IronErest

Held three series of heats. In the first series, cast iron is treated with a composition modifier, wt.%:

Copper20.0

Nickel40.0

Manganese10.0

Magnesium0 1

Calcium10.0

Silicon1,0

RZM0,1

Table 1

74-110

99-140

10.0

Yttrium Rest Iron

In the second series, cast iron is treated with a composition modifier, wt.%;

35.0

Copper 30.0 5.0

Nickel

Manganese 5.0

Magnesium 5.0

Calcium 4.0 5.0 5.0

Kremadj

Rare earth metal

Yttrium Else

Iron

In the third series, cast iron is treated with a composition modifier, wt.%:

Copper50.0

Nickel .20,0

Manganese 0.1

10.0 0.1

Magnesium

Kalyish 9.0

Silicon

RZM10,0

Yttrium-0,1

IronErest

The physicomechanical properties of piston rings made of cast iron of the first, second and third series of heats are given in table. 2-4, respectively.

3.1 15320 94,0106-108 99,017200130.0

3.2. 16800 103,0105-106 120,017480124.0

3.3 15900 112.0 106-104 115,017510142.0

Table 3

Table 4

105-107 130.0 109-108 120.0 107-109 135.0

7 73

Comparison of the fnziko-mechanical CBOucTff piston rings made of cast iron with the proposed modifier and the well-known shows that the test rings have a higher modulus of elasticity, a limit on the bending strength, a greater lock release when destroyed, and an increased hardness that provides increased wear resistance and ductility. The best properties are observed when using a Modifier with average content of components. The hardness of the rings in this case reaches 111-112 units, the tensile strength at bending is 140-160 kgf / mm.

The use of the proposed modifier allows to simplify the process of smelting iron as the alloying components are introduced directly into its composition and there is no need for additional doping with nickel and copper, to obtain high-strength nodular cast iron for thin-walled parts with enhanced: physical and mechanical properties and wear resistance; allows to increase the ductility and dynamic flexural strength, which helps to reduce the number of failures when parts work under conditions of significant alternating shock loads, piston rings made of high-strength cast iron with the proposed modifier can be used on the power

tons of load-loaded, forced engines.

Claims (2)

1. A modifier containing copper, nickel, manganese, magnesium, calcium, rare earth metals, iron, silicon, characterized in that, in order to simplify the smelting process and improve the physical and mechanical properties of high-strength nodular iron, it also contains yttrium in the following ratio of components , weight.%: Copper 20-50 20-40 Nickel 0.1-10 Manganese 0.1-10 Magnesium 0.1-10 Calcium Rare earth metals 0.1-10 Silicon 0.5-10 0.1-10 Yttrium Iron Rest 2. The modifier according to claim 1, wherein the total content of magnesium and ytt is not less than 4.0 weight Sources of information taken into account in the examination 1. USSR author's certificate number 4185 cl. C 22 C 35/00.