Steel 70S3A

Designation

Name The value
Designation GOST Cyrillic 70С3А
Designation GOST Latin 70C3A
Transliteration 70S3A
By chemical elements 70С3

Description

Steel 70S3A used: for the production of heavily loaded springs responsible and osobochistogo destination.

Note

Steel spring alloy of high quality.

Standards

Name Code Standards
Sheets and strips В23 GOST 103-2006
Bars and shapes В22 GOST 1133-71, GOST 2590-2006, GOST 2591-2006, GOST 2879-2006
Wire, steel, alloy В73 GOST 14963-78
Steel wire medium and high carbon В72 GOST 26366-84
Sheets and strips В33 GOST 4405-75
Bars and shapes В32 GOST 7417-75, GOST 7419-90, GOST 8559-75, GOST 8560-78, GOST 14955-77, GOST 14959-79, TU 14-1-2118-77, TU 14-178-179-88, TU 14-11-245-88, TU 14-136-367-2008

Chemical composition

Standard C S P Mn Cr Si Ni Fe Cu
GOST 14959-79 0.66-0.74 ≤0.025 ≤0.025 0.6-0.9 ≤0.3 2.4-2.8 ≤0.25 Rest ≤0.2
Fe is the basis.

Mechanical properties

Section, mm t отпуска, °C sT|s0,2, MPa σU, MPa d5, % y, % KCU, kJ/m2 HB, MPa HRC
Wire with special surface finishes for the manufacture of springs cold-wound in the delivery condition according to GOST 14963-78
0.5-14 - - ≤1030 - - - - -
Forgings section 16-25 mm. Annealing + Quenching in oil from 900 °C + Vacation
- 250 ≥1520 ≥1740 - ≥10 - - ≥60
Rolled steel. Hardened in oil from 830 °C to + Vacation at 450 °C
- - ≥1540 ≥1780 ≥10 - ≥235 - -
Forgings section 16-25 mm. Annealing + Quenching in oil from 900 °C + Vacation
- 350 ≥1520 ≥1740 ≥7 ≥17 ≥265 - ≥56
Rolled steel. Hardened in oil from 830 °C to + Vacation at 450 °C
- - ≥1440 ≥1710 ≥12 ≥32 ≥285 - -
Spring. Annealing at 840-850 °C. Wrapped at 850-880 °C. Quenching in oil 850-880 °C + Vacation at 460-470 °C
- - - - - - - 388-445 -
Rod forged. Annealing + Isothermal quenching from 900 °C with a hold at 320 °C
15-16 - - ≥1060 ≥2 ≥13 - - ≥60
Forgings section 16-25 mm. Annealing + Quenching in oil from 900 °C + Vacation
- 450 ≥1220 ≥1690 ≥6 - ≥363 - ≥49
Rolled steel. Hardened in oil from 830 °C to + Vacation at 450 °C
- - ≥1270 ≥1620 ≥16 ≥32 - - -
Rod forged. Annealing + Isothermal quenching from 900 °C with a hold at 340 °C
15-16 - - ≥1270 ≥4 ≥15 - - ≥49
Rolled steel. Hardened in oil from 830 °C to + Vacation at 450 °C
- - ≥1220 ≥1400 ≥20 ≥65 - - -
Rolled steel. Steel categories: 3, 3A, 3B, 3C, 3D, 4, 4A, 4B. Quenching in oil from 850 °C + Vacation at 470 °C
- ≥1470 ≥1670 ≥6 ≥25 - - -

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
HRC Rockwell hardness (indenter diamond spheroconical)

Physical characteristics

Temperature Е, HPa G, HPa l, W/(m · °C) a, 10-6 1/°C С, J/(kg · °C)
20 214 83 25 - -
100 208 81 26 114 480
200 198 76 27 123 510
300 192 79 28 128 520
400 185 69 29 133 535
500 180 67 29 137 565
600 152 57 29 141 585
700 139 52 28 143 620
800 132 49 27 143 620
1000 - - - 128 700

A description of the physical symbols

Name Description
Е The normal elasticity modulus
G Modulus of elasticity shear torsion
r Density
l Coefficient of thermal conductivity
R UD. the resistivity

Technological properties

Name The value
Weldability Does not apply to welded structures.
Склонность к отпускной хрупкости Inclined.
The temperature of forging Start - 1100 °C, the end - of 800 °C.
Flock-sensitive sensitivity not sensitive.