SU511378A1 - Cast iron - Google Patents

Description

(54) CAST IRON

The invention relates to the field of metallurgy, in particular to the search for wear-resistant cast irons used for wear-resistant parts, for example, wear parts of metallurgical and mining equipment. Cast iron is known for the following chemical composition, Ex.%: Carbon 2.2-3.4 2.8 -3.5 Silicon 0.6-2.0 Manganese Chromium 5.0-6.5 Aluminum 1.0-1.5 Iron Else Cast iron of this composition contains sulfur as impurities less than 0.2 wt.% And phosphorus less than 0. , 15 weight%. Cast iron is a white eutectic cast iron with a eutectic structure composed of a eutectic based on hexagonal chromium carbide (and has the following mechanical properties in the cast state :. The tensile strength of the bleached layer, kg / mm 237-39. Impact strength. bleached layer, kg / mm2 0.2 Hardness at a depth of 1O mm from the surface, PS, kg / mm2 41O-52O Hardness of the gray zone HB, kg / mm 32O-37O However, the known cast iron has poor hardenability on casting air with a cross section of more than 120 mm , resulting in large castings after Air quenching has low casting, mechanical properties and wear resistance. The wear resistance of known iron after quenching in air from a temperature of 970 ± 200 ° C - 0, 0431 g. This includes cast iron containing carbon, silicon, manganese, chromium, aluminum and iron, which additionally contains molybdenum, copper, cerium and calcium in the following ratio of components, wt.%:

Carbon1.8-3.6

Silicon2.6-3.4

Manganese0,4-5,0

Rom5.0-6.5

Aluminum0.01-0.9

Molybdenum, O 1-1,2

Copper0,1-1,8

Cerium 0,01-0,3

Calcium0.01-0.3

IronErest

The cast iron of this composition allows to increase the foundry, mechanical properties of wear resistance after quenching castings with a cross section of more than 120 mm.

Cast iron contains as impurities epur and phosphorus in an amount of less than 0.1 weight,%.

Cast iron has the following technological and mechanical properties:

L and flowability in a Keri spiral at a pouring temperature of 1435-151OOS, mm 430-510 Linear shrinkage,% 1.7-1.85

Flexural strength after quenching in air from a temperature of 9 70+ 20 wasps, kg / mm244-47

HRc hardness after

quenching in the air from

temperature 970 + 20ОС56-58

Wear resistance after

quenching in the air from

temperatures 970 +, 0293 gr.

The alloy is melted in an open induction furnace in the main crucible. Casting is carried out in dry sandy-clay forms with a diameter of 120 mm and a height of 250 mm.

Claims (1)

Invention Formula Cast iron containing carbon, silicon, J5 manganese, chromium, aluminum and iron, differing from the fact that, in order to increase the foundry, mechanical properties and wear resistance after quenching castings with a cross section of more than 12O mm, it additionally contains molybdenum, rd, cerium and calcium at the following ratio of components, wt.%: Carbon 1.8-3.6 Silicon 2.6-3.4 Manganese 0.4-5.0 Chromium 5.0-6.5 Aluminum 0.01-O, 9 Molybdenum 0.01-1.2 Copper 0.1-1.8 Cerium 0.01-0.3 Calcium 0.01-0.3 Iron Rest