Steel 25Х2ГНТА
Designation
| Name |
The value |
| Designation GOST Cyrillic |
25Х2ГНТА |
| Designation GOST Latin |
25X2GHTA |
| Transliteration |
25H2GNTA |
| The 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 norms |
В20 |
OST 1 90005-91 |
| Norms of calculation and design |
В02 |
PI 1.2.053-78 |
| Bulls. Blanks. Slabs |
В31 |
TU 14-1-1030-74, TU 1-92-156-90 |
| Sectional and shaped rolling |
В32 |
TU 14-1-1885-85, TU 14-1-3238-81, TU 14-1-3238-2006 |
| Pipes steel and connecting parts 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 |
The 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 |
The 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 characteristics
| Section, mm |
sT|s0,2, MPa |
σB, MPa |
d5, % |
y, % |
kJ/m2, кДж/м2 |
Brinell hardness number, 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 |
| Section |
Section |
| sT|s0,2 |
Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2% |
| σB |
Limit short-term strength |
| d5 |
Elongation after rupture |
| y |
The relative narrowing |
| kJ/m2 |
Toughness |
| HRC |
Rockwell hardness (indenter diamond spheroconical) |
Physical characteristics
| Temperature |
Е, ГПа |
r, кг/м3 |
l, Вт/(м · °С) |
a, 10-6 1/°С |
| 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 contamination |
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. |
