Steel 7X3
Designation
| Name |
The value |
| Designation GOST Cyrillic |
7Х3 |
| Designation GOST Latin |
7X3 |
| Transliteration |
7H3 |
| The chemical elements |
7Cr3 |
Description
7X3 steel is used: for the manufacture of tools (punches, matrices), a hot landing fasteners and blanks made of carbon and low-alloy construction steels in the horizontal forging machines; parts of dies (dies, punches, ejectors) for hot pressing and extruding of these materials on crank presses with small-scale production; bending, trimming and cutting dies.
Standards
| Name |
Code |
Standards |
| Sectional and shaped rolling |
В22 |
GOST 1133-71, GOST 2590-2006, GOST 2591-2006 |
| Sheets and stripes |
В33 |
GOST 4405-75 |
| Sectional and shaped rolling |
В32 |
GOST 5950-2000, GOST 7417-75, GOST 8559-75, GOST 8560-78, GOST 14955-77, TU 14-11-245-88, TU 14-1-1271-75 |
| Bulls. Blanks. Slabs |
В31 |
OST 24.952.01-89 |
Chemical composition
| Standard |
C |
S |
P |
Mn |
Cr |
Si |
Ni |
Fe |
Cu |
V |
Ti |
Mo |
W |
| GOST 5950-2000 |
0.65-0.75 |
≤0.03 |
≤0.03 |
0.15-0.45 |
3.2-3.8 |
0.1-0.4 |
≤0.4 |
The rest |
≤0.3 |
≤0.15 |
≤0.03 |
≤0.2 |
≤0.2 |
Fe is the basis.
Mechanical characteristics
| Section, mm |
t отпуска, °C |
sT|s0,2, MPa |
σB, MPa |
d5, % |
y, % |
kJ/m2, кДж/м2 |
HRC |
| - Heat to 650-700 °C. Quenching in oil 850-880 °C + Vacation at 480-500 °C (aging 1 HR) |
|
- |
1620-1710 |
1670-1760 |
4-7 |
16-19 |
- |
40-44 |
| Rolled steel. Quenching in oil with 860-880 °C to + Leave (exposure 2 hours) |
|
300 |
≥1650 |
≥1930 |
≥4 |
≥12 |
- |
≥52 |
| Long products (samples). Quenching in oil with 860-880 °C + Vacation at 500 °C (2H exposure) |
| - |
- |
≥1240 |
≥1320 |
≥10 |
≥36 |
- |
- |
| Rolled steel. Quenching in oil from 870 °C to + Leave at 500 °C (exposure 2 hours) |
|
- |
≥1240 |
≥1320 |
≥10 |
≥36 |
≥370 |
- |
| Rolled steel. Quenching in oil with 860-880 °C to + Leave (exposure 2 hours) |
|
400 |
≥1440 |
≥1690 |
≥5 |
≥24 |
- |
≥47 |
| Long products (samples). Quenching in oil with 860-880 °C + Vacation at 500 °C (2H exposure) |
| - |
- |
≥880 |
≥1030 |
≥12 |
≥34 |
- |
- |
| - |
- |
≥780 |
≥910 |
≥16 |
≥55 |
- |
- |
| - |
- |
≥550 |
≥690 |
≥18 |
≥68 |
- |
- |
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) |
Technological properties
| Name |
The value |
| Weldability |
does not apply to welded structures. |
| Propensity to temper brittleness |
inclined |
| Forging temperature |
Start - 1180 °C, the end - of 800 °C. the cross Sections up to 300 mm are cooled in the pit. |
| Flock-sensitive sensitivity |
sensitive |
