55S2

Coil springs and leaf springs used in automotive, tractor, railway transport and other branches of engineering.

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 95.68–97.38 1.5–2 0.6–0.9 < 0.3 < 0.2 < 0.25 < 0.035 0.52–0.6 < 0.035

Information on suppliers

Physical characteristics

Temperature, °C $$E\cdot 10^{9}$$, $$MPa$$
20 1.96

Mechanical properties at 20 °C

Rolling Standard Size, mm Tension Classifiers $$\sigma _{U}$$, $$MPa$$ $$\sigma_{P}$$, $$MPa$$ $$\psi$$, % $$KCU\cdot 10^{3}$$, $$\frac{J}{m^2}$$ d5, % Treatment
Alloy 760 440 42 160 21 Annealing 750-780 ° C, furnace cooled
Hire GOST 14959-79 1270 1175 30 6 Hardening and tempering

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Alloy GOST 14959-79 raw 285
Hire GOST 14959-79 heat-treated 241

Technological Properties

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

Critical point temperatures

Ac1, K Ac3(Acm), K Ar3(Arcm), K Ar1, K Mn, K
755 810 770 690 272

Analogues

USA Germany European Union
G92550 1.5026 (55Si7) 55Si

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

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
$$KCU\cdot 10^{3}$$ $$\frac{J}{m^2}$$ Impact toughness

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
Ar3(Arcm) K
Ar1 K
Mn K