Designation
| Name |
The value |
| Designation GOST Cyrillic |
21Х2НМФА |
| Designation GOST Latin |
21X2HMFA |
| Transliteration |
21H2NMFA |
| By chemical elements |
21Cr2НMoV |
Description
21KH2NMFA steel is used: for the manufacture of critical shtampovannyh structures; for heavy welded assemblies and structures, not subjected to the annealing or normalizing after welding due to large dimensions or design features.
Note
Complex alloyed high-quality steel with low carbon content. Steel 21KH2NVFA strengthen by heat treatment (quenching in oil with subsequent tempering or normalizing with tempering).
Standards
| Name |
Code |
Standards |
| Sheets and strips |
В33 |
GOST 11268-76, GOST 11269-76 |
| Sheets and strips |
В23 |
GOST 82-70 |
Chemical composition
| Standard |
C |
S |
P |
Mn |
Cr |
Si |
Ni |
Fe |
Cu |
V |
Ti |
Mo |
W |
| GOST 11268-76 |
0.19-0.23 |
≤0.025 |
≤0.025 |
0.3-0.7 |
1.9-2.4 |
0.17-0.37 |
0.8-1.2 |
Rest |
≤0.25 |
0.18-0.28 |
≤0.03 |
0.35-0.45 |
≤0.2 |
Fe is the basis.
Mechanical properties
| Section, mm |
σU, MPa |
d5, % |
d10 |
KCU, kJ/m2 |
| Steel hot-rolled sheet (4-60 mm) 4-th and 5-th categories. Quenching in oil with 925±15 °C, leave at 550-570 °C, air cooling |
|
≥1130 |
≥9 |
- |
≥390 |
| A sheet of thin (≤3.9 mm) hot - and cold-rolled. Quenching in oil with 925 °C + vacation at 500-570 °C, air cooling |
|
≥1128 |
≥9 |
- |
- |
| Flats on the other 14-1-4118-2004 |
| ≤3.9 |
490-736 |
≥15 |
≥11 |
- |
Description mechanical marks
| Name |
Description |
| σU |
Limit short-term strength |
| d5 |
Elongation after rupture |
| d10 |
Elongation after rupture |
| KCU |
Toughness |
