RU2308522C1 - Cast iron - Google Patents

Abstract

FIELD: metallurgy, in particular, cast iron compositions.

SUBSTANCE: cast iron contains components used in the following ratio, wt%: carbon 2.8-3.2; silicon 1.8-2.2; manganese 0.6-1.0; nickel 2.0-2.5; barium 0.005-0.01; aluminum 0.1-0.3; boron 0.01-0.02; copper 0.8-1.2; niobium 0.8-1.2; cobalt 0.3-0.8; chromium nitrides 0.1-0.3; iron the balance.

EFFECT: increased strength of cast iron.

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Description

The invention relates to the field of ferrous metallurgy, and in particular to compositions of cast iron, which can be used in railway, construction and road, agricultural tractor engineering, machine tool industry.

Known cast iron, containing, wt.%: Carbon 2.95-3.45; silicon 1.55-2.2; manganese 0.3-0.7; nickel 0.02-0.8; barium 0.12-0.05; one or more elements from the group of cerium, antimony, tin, cobalt 0.05-0.3; chromium nitrides 0.02-0.3; iron - the rest [1].

Known cast iron containing wt.%: Carbon 2.5-4.0; silicon 0.8-2.5; manganese 0.3-1.5; nickel 0-2.5; barium 0-0.2; aluminum 0-0.2; boron 0-1.0; copper 0-4.0; nickel 0-1.0; iron - the rest [2].

The objective of the invention is to increase the strength of cast iron.

The technical result is achieved by the fact that cast iron containing carbon, silicon, manganese, nickel, barium, aluminum, boron, copper, niobium, iron, additionally contains cobalt and chromium nitrides, with the following ratio of components, carbon is 2.8-3.2; silicon 1.8-2.2; manganese 0.6-1.0; nickel 2.0-2.5; barium 0.005-0.01; aluminum 0.1-0.3, boron 0.01-0.02; copper 0.8-1.2; niobium 0.8-1.2; cobalt 0.3-0.8; chromium nitrides 0.1-0.3; iron is the rest.

The table shows the composition of cast iron

Table Components Composition, wt.%: one 2 3 Carbon 2,8 3.0 3.2 Silicon 2.2 2.0 1.8 Manganese 1,0 0.8 0.6 Nickel 2,5 2,3 2.0 Barium 0.005 0.007 0.01 Aluminum 0.3 0.2 0.1 Boron 0.01 0.015 0.02 Copper 0.8 1,0 1,2 Niobium 1,2 1,0 0.8 Cobalt 0.8 0.5 0.3 Chromium nitrides 0.1 0.2 0.3 Iron rest rest rest Tensile Strength, MPa ~ 900 ~ 900 ~ 900

The increase in the strength of cast iron is due to the complex effect of the components that make up its composition. Nickel and cobalt improve the metal base of cast iron. Niobium strengthens the solid solution. Boron stabilizes carbides. Copper promotes graphitization, increases the content of perlite in the alloy. Manganese contributes to the grinding of perlite. Barium and aluminum act as deoxidizers. Chromium nitrides give the structure of cast iron fine grain.

Cast iron is smelted in electric furnaces and centrifugally cast in hot (400-500 ° C) metal molds coated with refractory clay. Castings are subjected to normalization at a temperature of 900-950 ° C and tempering at a temperature of 350-450 ° C.

Information sources:

1. SU 1507845, C22C 37/04, 1989.

2. JP 60-121254, C22C 37/08, 1985.

Claims (1)

Cast iron containing carbon, silicon, manganese, nickel, barium, aluminum, boron, copper, niobium, iron, characterized in that it additionally contains cobalt and chromium nitrides in the following ratio of components, wt.%: Carbon 2.8-3, 2; silicon 1.8-2.2; manganese 0.6-1.0; nickel 2.0-2.5; barium 0.005-0.01; aluminum 0.1-0.3; boron 0.01-0.02; copper 0.8-1.2; niobium 0.8-1.2; cobalt 0.3-0.8; chromium nitrides 0.1-0.3; iron the rest.