50

gears, mill rolls, rods, heavy duty shafts, axles, tires, light duty springs and springs, plowshares, fingers track link, clutch transmissions, body injectors and other parts operating friction.

Classification

Country Section Category
CIS, Russia, Ukraine Structural steel Carbonaceous quality structural steel

Chemical composition

Standard Fe, % Si, % Mn, % Cr, % Cu, % Ni, % As, % P, % C, % S, %
GOST 1050-88 97.275–98.86 0.17–0.37 0.5–0.8 < 0.25 < 0.3 < 0.3 < 0.08 < 0.035 0.47–0.55 < 0.04

Information on suppliers

Physical characteristics

Temperature, °C $$E\cdot 10^{9}$$, $$MPa$$ $$\alpha\cdot 10^{6}$$, $$K^{-1}$$ $$\varkappa$$, $$\frac{W}{m\cdot K}$$ $$\rho$$, $$\frac{kg}{m^3}$$ $$c\cdot 10^{-3}$$, $$\frac{J}{kg\cdot K}$$ $$R\cdot 10^{-6}$$, $$\Omega\cdot m$$
20 216 48 7810 0.272
100 213 11.2 48 0.487
200 207 12 47 0.5
300 200 12.8 44 0.517
400 180 13.4 41 0.533
500 171 13.9 38 0.559
600 154 14.2 35 0.584
700 136 14.5 31
800 123 13.4 27

Mechanical properties at 20 °C

Rolling Standard Size, mm Tension Classifiers $$\sigma _{U}$$, $$MPa$$ $$\sigma_{P}$$, $$MPa$$ $$\epsilon_L$$, % $$\psi$$, % Treatment
Metal rolling GOST 1050-88 < 80 630 375 14 40 Normalization
Metal rolling GOST 1050-88 cold-work 660 6 30
Metal rolling GOST 1050-88 annealing 560 12 40
Sheet 6–60 fat 580 17 Annealing

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Round GOST 10702-78 hot rolling 217
Metal rolling GOST 1050-88 hot rolling 241
Metal rolling GOST 1050-88 calibrated, cold-work 255
Metal rolling GOST 1050-88 annealing, calibrated 217
Metal rolling GOST 1050-88 annealing, hot rolling 207

Technological Properties

Weldability Flake Susceptibility Propensity to temper brittleness
Difficult to weld insensitive not inclined

Critical point temperatures

Ac1, K Ac3(Acm), K Ar3(Arcm), K Ar1, K Mn, K
725 760 750 690 300

Analogues

USA Germany
G10550 1.0535 (C55)

Standards

Standard Description
GOST 1050-88

Description of chemical elements

Element Units of measurement Description
Fe % Iron
Si % Silicon
Mn % Manganese
Cr % Chrome
Cu % Copper
Ni % Nickel
As % Arsenic
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)
$$\rho$$ $$\frac{kg}{m^3}$$ The density of the material
$$c\cdot 10^{-3}$$ $$\frac{J}{kg\cdot K}$$ The specific heat of the material (range 20°C–T)
$$R\cdot 10^{-6}$$ $$\Omega\cdot m$$ Electrical resistivity

Description of mechanical properties

Parameter Units of measurement Description
$$\sigma _{U}$$ $$MPa$$ Ultimate tensile strength
$$\sigma_{P}$$ $$MPa$$ Proportionality limit
$$\epsilon_L$$ % Elongation at break (longitudinal)
$$\psi$$ % 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
Ar3(Arcm) K
Ar1 K
Mn K