SU730870A1 - Graphitized steel - Google Patents

Description

(S 4) GRAPHITE STEEL

one

The invention relates to metallurgy, in particular, to the search for graphitized steels with high elastoplastic properties and wear resistance. Steel is intended for the manufacture of parts for metal aggregates operating under friction conditions at BbtcoKHX specific loads without or at; insufficient lubrication, including brake drums, toothed. and pistons.

Closest to the present invention is graphitized 1: OVAN steel containing, by weight. %:

Carbon

0.9-1.4

Silicon 0.9-1.3

Manganese 0,4-O, 8 0,6-15

Copper

Iron

and inevitable

Rest

impurities

Liquid fluid is izvestyuyu steel at 152O With chill sample 11213O.

The disadvantages of the well-known steel are low manufacturability, a tendency to anisotropy of the structure over the cross section from a molten metal forming a transparent metal base during the annealing process, which reduces its elastic-plastic properties.

The purpose of the invention is to improve the technological and elastic-plastic properties of steel.

. The goal is achieved by the fact that the proposed graphitized steel "additionally contains calcium, antimony and rare earth metals in the following ratio; components,% Beci:

1.2-1.4

Carbon 0.9–1.3 Silicon 0.3–0.7 Manganese 0.3–1.5 Copper 0.1–0.9 Antimony 0.01–0.25 Calcium Red Earth, OO5 – O, O5 – ny metals Iron Else

Impurities

Sulfur Not more than 0.03

Phosphorus not more than 0.05

 Chrome Not more than 0.20

The proposed ratio of the main components in the steel makes it possible to obtain castings with ferritic ferriter-ferrite,. perlite, austenitic, martensitic and sorbitol structures, using the processes of annealing, normalization, quenching and tempering, 10 chemical compounds of known and proposed steels are given in table 1.

Table 2 shows the material properties of steel. In Table 3, their physical and mechanical properties in the cast state of tin.: 15 In Table. 4 - fcsso-mechanical properties of steels in heat treatment condition ..

Graphitizing} annealing is carried out in the following way: heating up to 950 C 20 for 7-8 hours, supplying this salt to this temperature for 8-10 hours, cooling in 1.5.4 to 740-72 ° C, keeping at this temperature for 5 7 hours

and slow cooling of samples and castings to BOO-bbOs together with the furnace with subsequent cooling of them in calm air.

The offered steel is technological and does not interact with the material of the casting mold. High casting properties allow $ sweat to cast shaped castings with a wall thickness of 5-6 mm.

The wear resistance of steel increases with increasing content of granular pearlite in the structure and hardness of steel. The hardness of steel after graphitization annealing 145-185 HB. After normalization, it rises to 280-360 HB.

Tests show that the proposed steel after graphitizing annealing is well processed by cutting. Castings from such steel are machined with minera-ceramic incisors at a cutting speed of 13 O-26 O m / min. Relative machinability, steel with hardness 16O-17O HB higher than the known steel.

So blitz Fluidity with respect to the 112-130 sample, mm 1.72-L76 Linear shrinkage,% Tendency to hot cracks formed (relative, standard steel 110G13L) 0.36-0.42 Temporary resistance, kgf / mm Elongation ,%: 6.8-7.2 Impact viscosity, cts-m / cm 3.2-3.5

Time resistance

52-56 kgf / mm Else elongation,%, 15.1-15.3 Impact viscosity, 3.9-4.58, p-8.8

Table i

Table 3

Ta lb and c and 4

70-7578-82

Claims (1)

86-9О 15О-16О, 165-173 172-18О 1.91-1.93 1,851.85-1.81, 15-0,2О О, 13-О, 16 О, 12-О, 14 61-63 65-6768-70 7.0-7.3 7.7- 7.9 7.7-8.3 5.6-5.8 6.3-6.5 6.8-7.0 17.0-20 , 0 21-23 23-25 8.6-9 9.1-9.5 Claims of the invention Grafitiairovain steel containing perper, silicon, manganese, copper and jelly is characterized in that with whole technological and elastic-plastic enhancements properties, it additionally contains calcium, antimony and rare earth metals in the following ratio of components, weight,%: Carbon1.2-1.4 Silicon0.9-1.3 7 0.3-0.7 arganese 0.3-1.5 0.1–0.9 orema 0.01–0.25 Calcium Red-earth0, 005–0.05 metals Ostalye Iron Sources of information, and Tide into account in the examination 1, USSR Author's Certificate 451,790, cl. C 22 C 38/14, 1975