SU926060A1 - Structural steel composition - Google Patents

Description

() CONSTRUCTION STEEL

The invention relates to metallurgy, in particular, to steel used for the manufacture of heavy loaded parts, automobiles, tractors and machine tools operating at room and negative temperatures. Known steel 1, content, wt.%: 0,27-0,3 Carbon; Silicon 0.17-0.37 0.30-0.60 Manganese 2.30-2.70 0.20-0.30 Molybdenum 0.06-0.12 Vanadium Else Iron This steel has a low yield strength, contains ({) is an icytic molybde and has a low saturation rate when nitriding. Closest to the proposed technical essence and the achieved effect ({) ectu is constructional steel 121, containing, wt.%:, Carbon O, Silicon 0.56-1.5 Manganese 0.3-2 Vanadium 0.21 -1 Chrome 0.71-3 Aluminum 0.3 Iron Else This steel does not provide the required set of properties.; in particular, plasticity, elimination of intergranular fragility, intensity (}), and nitration of the nitriding process. The purpose of the invention is to increase the strength, ductility, toughness, intensities (nitriding of the nitriding process and the elimination of intercrystalline brittleness di (X of the bonding layer. The goal is achieved by the addition of germanium in the following ratio, wt.%:

0.30-0, its 0.30-0.60 0.17-0.37

1.5-2.5 0.20-0.50 0.20-0.80 Else

The steels are melted in a 50 kg induction furnace. The chemical composition of the steels is given in Table. one.

After heat treatment (quenching from into oil, tempering from

Steel

Chemical composition 5-J-§ .-. | -MD ... yL§e

0.30 0.17 0.30 1,500,200,20

0.39 0.26 0.22 1.870,, 8

0.45 0.37 0.60 2.500.500.80

9

0, C} 1.02 1.2Jf 1.650.5415 .4

98

75

260604

 Within 2 hours in the oil), the proposed and known steels have the following properties (see Table 2).

Comparative properties of the proposed and known and known steels after nitriding are given above. 3Thus, the proposed steel surpasses the one known for its complex of mechanical properties and has a high tendency to nitrate with a large depth of the diffusion layer and the absence of brittle nitride phases,

Table 1

Fe

0,0050,004ast.

0,0010,004ast.

0,0050,005

0.31 0.0050.004.

Table

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1L 1L

00 w

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state of emergency

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SI Claims of Invention Structural steel containing carbon, manganese, silicon, chromium, vanadium, and iron is different in that, in order to increase strength, ductility, impact strength, to intensify the nitriding process and eliminate the intergranular fragility of the diffusion layer, it additionally contains germanium in the following ratio of components, wt.%: Carbon 0.30-0.45 Manganese, 0.30-0.60 92 0 0.17-0.37 Silicon 1.5-2.50 0.20-0 , 50 Vanadium 0.20-0.80 Germanium Iron Else Sources of information taken into account during the examination 1. Steel Mar and ZOHZMF. GOST 45 3-71. Steel alloyed, constructional, brands and technical requirements. 2. For Japan No. 52-2758, cl. 10 I 172 (C 22 C 37/24) 53-113214, published. 03.10.78.

Claims (1)

Formula inventions Structural steel containing carbon, manganese, silicon, chromium, vanadium and iron, characterized in that, in order to increase strength, ductility, impact strength, intensify the nitriding process and eliminate the intergranular fragility of the diffusion layer, it additionally contains germanium with the 10 following ratio of components, wt.%: Carbon 0.30-0.45 Manganese, 0.30-0.60 tS Silicon O, 17 “O, 37 Chrome 1,5-2,50 Vanadium 0.20-0.50 Germanium 0.20-0.80 Iron Else R