Steel 25Х2ГНТА

Designation

Name The value
Designation GOST Cyrillic 25Х2ГНТА
Designation GOST Latin 25X2GHTA
Transliteration 25H2GNTA
By chemical elements 25Cr2MnНTi

Description

25Х2ГНТА steel is used: for the manufacture of beams, bolts, axes, vessels, working under excessive internal pressure; the rims of the driven wheels of the traction gear trains, gear and other upgradable parts, tubular billets and pipes.

Note

Chromatorgraphy high quality high strength alloy steel.
Can be used at temperatures up to -80 °C (wall thickness not more than 100 mm).

Standards

Name Code Standards
Classification, nomenclature and General rules В20 OST 1 90005-91
Norms for calculation and design В02 PI 1.2.053-78
Blanks. Of the workpiece. Slabs В31 TU 14-1-1030-74, TU 1-92-156-90
Bars and shapes В32 TU 14-1-1885-85, TU 14-1-3238-81, TU 14-1-3238-2006
Steel pipes and fittings to them В62 TU 14-3-289-74

Chemical composition

Standard C S P Mn Cr Si Ni Fe Cu Ti
TU 14-1-1885-85 0.22-0.29 ≤0.015 ≤0.025 0.8-1.1 1.3-1.7 0.2-0.5 0.9-1.3 Rest ≤0.25 0.02-0.06
TU 14-1-3238-81 0.22-0.29 ≤0.025 ≤0.025 0.8-1.1 1.3-1.7 0.2-0.5 0.9-1.3 Rest - 0.03-0.09
Fe is the basis.
According to TU 14-1-3238-81 the chemical composition is given for steel grade 25H2GNTA. For steel grade 25Х2ГНТА-СШ the content S≤0,015%.
According to TU 14-1-1885-85, the chemical composition is given for steel grade 25Х2ГНТА-ВД. To ensure the required grain size, it is allowed to introduce vanadium in the steel smelting at the rate of its content in steel no more than 0.10%, the content of which in steel is not determined. The presence of tungsten to 0.20%, molybdenum to 0.15% is not a rejection sign. The allowable deviation in manganese content in steel is + 0.010 / -0.020%, in titanium content +0.040%.

Mechanical properties

Section, mm sT|s0,2, MPa σU, MPa d5, % y, % KCU, kJ/m2 HB, MPa HRC
Gradation of performance properties of the finished heat-treated parts for OST 1 90005-91
- - 1370-1620 - - - 388-445 41-46
Bars and rods, hot rolled, forged and calibrated. Normalization at 880-920 °C + Quenching in oil 840-860 °C + Vacation at 160-200 °C, air cooling
≥1175 ≥1470 ≥10 ≥45 ≥690 388-515 -
Bars of steel 25Х2ГНТА on the other 14-1-1885-85. Normalization at 880-920 °C + Quenching in oil 840-860 °C + Vacation at 160-200 °C, air cooling. In the graph KCU KCU values are shown along the fiber/KCU across the grain
≥1175 ≥1470 ≥10 ≥45 ≥686/- 387-514 -

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
KCU Toughness
HB Brinell hardness number
HRC Rockwell hardness (indenter diamond spheroconical)

Physical characteristics

Temperature Е, HPa r, kg/m3 l, W/(m · °C) a, 10-6 1/°C
20 195 7800 - -
100 - - 419 12
200 - - 411 13
300 - - 407 137

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
Macrostructure and pollution Macrostructure of steel when testing for the breaks in the longitudinal direction and transverse templeto selected from rolled, should not have shrinkage, porosity, bubbles, cracks, delamination, inclusions and placenow and defects of fracture, listed in Annex 3 GOST 10243. The Central porosity, point heterogeneity and phase separation in the square should not exceed 1 points; layer-by-layer crystallization and the bright loop - 3 points reference scales GOST 10243. All other defects under GOST 10243, are not allowed. Pollution steel non-metallic inclusions should be according to the average score is not higher (in points): oxides of point 1,5, 2,0 stroke oxides, silicates fragile 1,0, 1,0 silicates plastic, silicates, non-deformed 2,5, 2,5 sulfides, nitrides stroke and point 1,0.