Steel 70S2KHA (ЭИ142)
Designation
| Name |
The value |
| Designation GOST Cyrillic |
70С2ХА |
| Designation GOST Latin |
70C2XA |
| Transliteration |
70S2HA |
| The chemical elements |
70С2Cr |
| Name |
The value |
| Designation GOST Cyrillic |
ЭИ142 |
| Designation GOST Latin |
EI142 |
| Transliteration |
EhI142 |
| The chemical elements |
- |
Description
70S2KHA steel is used: for the manufacture of springs for watches; large springs for critical applications; cold-rolled heat-treated ribbon with a thickness of 0.05 to 1.30 mm and rolled heat-treated strip thickness 0.15−2.00 mm for the manufacture of spring details and springs, with the exception of the crown; measuring tapes.
Note
Steel spring alloy of high quality.
Standards
| Name |
Code |
Standards |
| Sectional and shaped rolling |
В32 |
GOST 14959-79, TU 14-1-2118-77, TU 14-1-505-73, TU 14-11-245-88, TU 14-136-367-2008 |
| Tapes |
В34 |
GOST 2283-79, GOST 21996-76, GOST 21997-76, TU 3-939-81, TU 14-1-2992-80 |
| Steel wire medium- and high-carbon |
В72 |
GOST 26366-84 |
Chemical composition
| Standard |
C |
S |
P |
Mn |
Cr |
Si |
Ni |
Fe |
Cu |
| GOST 14959-79 |
0.65-0.75 |
≤0.025 |
≤0.025 |
0.4-0.6 |
0.2-0.4 |
1.4-1.7 |
≤0.25 |
The rest |
≤0.2 |
Fe is the basis.
According to TU 14-1-505-73, by agreement of the parties for special purpose hardware, steel should be supplied with reduced content limits of elements without treatment with synthetic slag and purging with argon.
Mechanical characteristics
| Section, mm |
σB, MPa |
d4 |
HV, MPa |
| Tape cold-rolled heat-treated (0,05-1,30 mm) for spring parts and springs according to GOST 21996-76 and flattened strip (0,15-2,00 mm) according to GOST 21997-76 (listed group strength tape) |
| - |
1270-1570 |
- |
375-485 |
| - |
1580-1860 |
- |
486-600 |
| - |
≥1860 |
- |
≥600 |
| Cold-rolled steel strip of 0.1-4.0 mm according to GOST 2283-79 on delivery |
| 0.1-4 |
780-1180 |
- |
- |
| 0.1-4 |
≤880 |
≥8 |
- |
Description mechanical marks
| Name |
Description |
| Section |
Section |
| σB |
Limit short-term strength |
| d4 |
Elongation after rupture |
| HV |
The Vickers hardness |
Technological properties
| Name |
The value |
| Weldability |
Does not apply to welded structures. |
| Propensity to temper brittleness |
Tend not. |
| Flock-sensitive sensitivity |
not sensitive. |
| Features of production |
Rod on the other 14-1-505-73 comes Beloretsky metallurgical plant. |
