Designation
| Name |
The value |
| Designation GOST Cyrillic |
25Х2Н4МА |
| Designation GOST Latin |
25X2H4MA |
| Transliteration |
25H2N4MA |
| By chemical elements |
25Cr2Н4Mo |
Description
25KH2N4MA steel is used: for the production of large connecting rods, couplings and other parts, which are requirements of high viscosity and hardenability.
Note
Structural steel high-quality romancelatina.
Standards
| Name |
Code |
Standards |
| Bars and shapes |
В32 |
GOST 4543-71, GOST 10702-78, GOST 14955-77, TU 14-1-2118-77, TU 14-1-950-74, TU 14-11-245-88, TU 14-136-367-2008 |
| Bars and shapes |
В22 |
GOST 8319.0-75 |
| Blanks. Of the workpiece. Slabs |
В31 |
OST 3-1686-90, TU 14-1-4944-90 |
| Classification, nomenclature and General rules |
В30 |
OST 3-98-80 |
Chemical composition
| Standard |
C |
S |
P |
Mn |
Cr |
Si |
Ni |
Fe |
Cu |
V |
Ti |
Mo |
W |
| TU 14-1-950-74 |
0.21-0.28 |
≤0.025 |
≤0.025 |
0.25-0.55 |
1.35-1.65 |
0.17-0.37 |
4-4.4 |
Rest |
≤0.25 |
≤0.05 |
≤0.03 |
0.3-0.4 |
≤0.2 |
| GOST 4543-71 |
0.21-0.28 |
≤0.025 |
≤0.025 |
0.25-0.55 |
1.35-1.65 |
0.17-0.37 |
4-4.4 |
Rest |
≤0.3 |
≤0.05 |
≤0.03 |
0.3-0.4 |
- |
Fe is the basis.
GOST 4543-71 regulates the content of high-quality steel: P≤0,025%; S≤0.015%; Сu≤0.25%. When the alloying Mo is replaced with W, the designation of the steel grade will be 25Х2Н4ВА.
Mechanical properties
| Section, mm |
sT|s0,2, MPa |
σU, MPa |
d5, % |
y, % |
KCU, kJ/m2 |
HB, MPa |
| Hot-rolled steel and hot rolled with special surface finish |
| - |
- |
- |
- |
- |
- |
≤255 |
| Steel calibrated and calibrated with special surface finish |
| - |
- |
- |
- |
- |
- |
≤269 |
| Bars and strip hot rolled and forged. Quenching in oil with 835-865 °C + vacation at 520-600 °C, cooling in water or oil |
| 25 |
932 |
1079 |
12 |
50 |
883 |
321-363 |
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 |
