Steel 20KH25N20S2 (ЭИ283)

Designation

Name The value
Designation GOST Cyrillic 20Х25Н20С2
Designation GOST Latin 20X25H20C2
Transliteration 20H25N20S2
By chemical elements 20Cr25Н20С2
Name The value
Designation GOST Cyrillic ЭИ283
Designation GOST Latin EI283
Transliteration EhI283
By chemical elements -

Description

20KH25N20S2 steel is used: for manufacturing parts of furnaces, operating at temperatures up to +1100 °C in air and hydrocarbon atmospheres; hangers and supports in boilers; pipe electrolysis and pyrolysis plants.

Note

Steel heat-resistant austenitic class.
The recommended maximum operating temperature for a long time +1050 °C. the Temperature of intensive scaling in air +1100 °C.
In the temperature range 600−800 °C is prone to embrittlement due to the formation of σ-phase.

Standards

Name Code Standards
Bars and shapes В22 GOST 1133-71, GOST 2590-2006, GOST 2591-2006, GOST 2879-2006
Sheets and strips В23 GOST 19903-74, GOST 19904-90, GOST 103-2006, GOST 19903-90
Sheets and strips В33 GOST 4405-75, GOST 5582-75, TU 14-1-2186-77
Classification, nomenclature and General rules В30 GOST 5632-72
Bars and shapes В32 GOST 5949-75, GOST 7417-75, GOST 8559-75, GOST 8560-78, GOST 14955-77, TU 14-11-245-88
Blanks. Of the workpiece. Slabs В31 OST 3-1686-90, TU 14-1-1213-75
Processing of metals by pressure. Forgings В03 STP М386-79
Wire, steel, alloy В73 TU 14-1-5361-98

Chemical composition

Standard C S P Mn Cr Si Ni Fe Cu V Ti Mo W
GOST 5632-72 ≤0.2 ≤0.02 ≤0.035 ≤1.5 24-27 2-3 18-21 Rest ≤0.3 ≤0.2 ≤0.2 ≤0.3 ≤0.2
Fe is the basis.

Mechanical properties

Section, mm sT|s0,2, MPa σU, MPa d5, % y, %
Rolled steel. Annealing in air or in water from 1100-1150 °C
- ≥255 ≥520 ≥30 ≥47
Hot rolled sheet (of 1.5-3.9 mm) and cold rolled (0,7-3,9 mm) steel according to GOST 5582-75. Quenching in water or air from 1050-1100 °C
- - ≥490 ≥35 -
Bars hot rolled and forged according to GOST 5949-75. Annealing in air or in water 1100-1150 °C
≥295 ≥590 ≥35 ≥50
Rolled steel. Annealing in air or in water from 1100-1150 °C
- ≥210 ≥490 ≥35 ≥50
- ≥165 ≥320 ≥40 ≥55
- ≥110 ≥195 ≥50 ≥63

Description mechanical marks

Name Description
sT|s0,2 Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%
σU Limit short-term strength
d5 Elongation after rupture
y The relative narrowing

Physical characteristics

Temperature r, kg/m3 l, W/(m · °C) a, 10-6 1/°C
0 7720 - -
20 7720 - -
100 7680 15 161
800 7440 27 181
900 7390 29 185
500 - 22 -
600 - 24 178
700 - 25 178
300 - - 161
1000 - - 185
1200 - - 188

A description of the physical symbols

Name Description
Е The normal elasticity modulus
r Density
l Coefficient of thermal conductivity
R UD. the resistivity

Technological properties

Name The value
Склонность к отпускной хрупкости inclined in the range of 600-800 With due to the formation of b-phase
The temperature of forging Beginning - 1170 °C, the end - 850 °C air Cooling.