70S3A

Heavily loaded responsible springs.

Classification

Country Section Category
CIS, Russia, Ukraine Structural steel Spring-spring structural steel

Chemical composition

Standard Fe, % Si, % Mn, % Cr, % Cu, % Ni, % P, % C, % S, %
GOST 14959-79 94.76–96.34 2.4–2.8 0.6–0.9 < 0.3 < 0.2 < 0.25 < 0.025 0.66–0.74 < 0.025

Information on suppliers

Physical characteristics

Temperature, °C $$E\cdot 10^{9}$$, $$MPa$$ $$\alpha\cdot 10^{6}$$, $$K^{-1}$$ $$\varkappa$$, $$\frac{W}{m\cdot K}$$ $$c\cdot 10^{-3}$$, $$\frac{J}{kg\cdot K}$$
20 2.14 25
100 2.08 11.4 26 0.48
200 1.98 12.3 27 0.51
300 1.92 12.8 28 0.52
400 1.85 13.3 29 0.535
500 1.8 13.7 29 0.565
600 1.52 14.1 29 0.585
700 1.39 14.3 28 0.62
800 1.32 12.8 27 0.7

Mechanical properties at 20 °C

Rolling Standard Size, mm Tension Classifiers $$\sigma _{U}$$, $$MPa$$ $$\sigma_{P}$$, $$MPa$$ $$\psi$$, % d5, % Treatment
Hire GOST 14959-79 1670 1470 25 6 Tempering 850 ° C, oil, leave 470 ° C

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Alloy GOST 14959-79 annealing 269
Alloy GOST 14959-79 raw 302

Technological Properties

Weldability Flake Susceptibility Propensity to temper brittleness
Not applicable for welded structures not sensitive loathsome

Critical point temperatures

Ac1, K Ac3(Acm), K Mn, K
765 780 270

Analogues

Bulgaria
70S3A

Standards

Standard Description
GOST 14959-79

Description of chemical elements

Element Units of measurement Description
Fe % Iron
Si % Silicon
Mn % Manganese
Cr % Chrome
Cu % Copper
Ni % Nickel
P % Phosphorus
C % Carbon
S % Sulfur

Description of physical characteristics

Parameter Units of measurement Description
$$E\cdot 10^{9}$$ $$MPa$$ Elastic modulus
$$\alpha\cdot 10^{6}$$ $$K^{-1}$$ Coefficient of thermal (linear) expansion (range 20°C–T)
$$\varkappa$$ $$\frac{W}{m\cdot K}$$ Coefficient of thermal conductivity (the heat capacity of the material)
$$c\cdot 10^{-3}$$ $$\frac{J}{kg\cdot K}$$ The specific heat of the material (range 20°C–T)

Description of mechanical properties

Parameter Units of measurement Description
d5 % Elongation at break
$$\sigma _{U}$$ $$MPa$$ Ultimate tensile strength
$$\sigma_{P}$$ $$MPa$$ Proportionality limit
$$\psi$$ % Reduction in cross section on fracture

Designation of types of weldability

Parameter Units of measurement Description
no limits Welding is performed without heating and without subsequent heat treatment
Boundedly welded Welding is possible with heating up to 100–120 °C and subsequent heat treatment
Difficult to weld For obtaining quality welded joints, additional operations are required: heating up to 200–300 °C for welding, heat treatment after welding — annealing
Not applicable for welded structures

Description of temperatures of critical points

Parameter Units of measurement Description
Ac1 K
Ac3(Acm) K
Mn K