RU2361000C1 - Cast iron - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy field, particularly, to content of cast iron. It can be used for manufacturing of piston rings of internal combustion engine. Cast iron contains, wt %: carbon 3.3-3.7; silicon 0.8-1.4; manganese 0.8-1.4; chrome 0.8-1.4; nickel 2.7-2.9; copper 0.8-1.4; phosphorus 0.05-0.1; molybdenum 0.5-0.7; niobium 0.8-1.4; aluminium 2.0-2.2; zirconium 0.1-0.15; boron 0.05-0.1; rhenium 0.2-0.3; strontium 0.001-0.002; iron - the rest. Cast iron allows high brittle strength.

EFFECT: cast iron hardening.

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Description

The invention relates to the field of metallurgy and relates to compositions of cast iron, which can be used for the manufacture of piston rings of internal combustion engines.

Known cast iron, containing, wt.%: Carbon 2.5-4.0; silicon 0.8-2.5; manganese 0.3-1.5; chrome 0-1.5; nickel 0-2.5; copper 0-4.0; phosphorus 0.05-1.5; molybdenum 0-0.8; niobium 0-1.0; aluminum 0-0.2; zirconium 0-1.0; boron 0-1.0; iron - the rest [1].

The invention is asked to increase the brittle strength of cast iron.

The technical result is achieved by the fact that cast iron containing carbon, silicon, manganese, chromium, nickel, copper, phosphorus, molybdenum, niobium, aluminum, zirconium, boron, iron, additionally includes rhenium and strontium, in the following ratio, wt.%: carbon 3.3-3.7; silicon 0.8-1.4; manganese 0.8-1.4; chrome 0.8-1.4; nickel 2.7-2.9; copper 0.8-1.4; phosphorus 0.05-0.1; molybdenum 0.5-0.7; niobium 0.8-1.4; aluminum 2.0-2.2; zirconium 0.1-0.15; boron 0.05-0.1; rhenium 0.2-0.3; strontium 0.001-0.002; iron is the rest.

The table shows the composition of cast iron.

Table Components Content, wt.% In the compositions one 2 3 Carbon 3.3 3,5 3,7 Silicon 1.4 1,1 0.8 Manganese 0.8 1,1 1.4 Chromium 1.4 1,1 0.8 Nickel 2.9 2,8 2.7 Copper 0.8 1,1 1.4 Phosphorus 0.1 0.08 0.05 Molybdenum 0.5 0.6 0.7 Niobium 1.4 1,1 0.8 Aluminum 2.0 2.1 2.2 Zirconium 0.1 0.13 0.15 Boron 0.05 0.08 0.1 Rhenium 0.2 0.25 0.3 Strontium 0.002 0.0015 0.001 Tensile strength after 100 heat shifts (heating to 750 ° C - cooling to 20 ° C), MPa ~ 850 ~ 850 ~ 850 Iron rest rest rest

In the composition of cast iron, the components manifest themselves as follows.

Chrome and boron stabilize carbides. Chrome and aluminum inhibit the growth of scale. Molybdenum, rhenium and niobium strengthen the solid solution. Nickel and copper increase the strength and plastic properties of the alloy. Phosphorus forms a low-melting eutectic, consisting of austenite and iron phosphide, contributing to the grinding of grain. Zirconium strengthens grain boundaries. Strontium reduces the amount of gas inclusions in the alloy.

Cast iron is smelted in cupola furnaces, by a duplex process or in electric furnaces, and cast into hot (400-450 ° C) metal molds coated with refractory clay. To relieve internal stresses, castings are annealed at a temperature of 550 ° C.

Information sources

1. JP 61-026754, C22C 37/08, 1986.

Claims (1)

Cast iron containing carbon, silicon, manganese, chromium, nickel, copper, phosphorus, molybdenum, niobium, aluminum, zirconium, boron and iron, characterized in that it additionally contains rhenium and strontium in the following ratio of components, wt.%:
carbon 3.3-3.7 silicon 0.8-1.4 manganese 0.8-1.4 chromium 0.8-1.4 nickel 2.7-2.9 copper 0.8-1.4 phosphorus 0.05-0.1 molybdenum 0.5-0.7 niobium 0.8-1.4 aluminum 2.0-2.2 zirconium 0.1-0.15 boron 0.05-0.1 rhenium 0.2-0.3 strontium 0.001-0.002 iron rest