25

axles, shafts, couplings, dogs, levers, plugs, washers, rollers, bolts, flanges, T-joints, fasteners and other non-critical parts; after HTO — screws, bushings, dogs, and other parts, which are requirements of high surface hardness and wear resistance at low core strength.

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 97.525–99.11 0.17–0.37 0.5–0.8 < 0.25 < 0.3 < 0.3 < 0.08 < 0.035 0.22–0.3 < 0.04

Information on suppliers

Physical characteristics

Temperature, °C $$E\cdot 10^{9}$$, $$MPa$$ $$\alpha\cdot 10^{6}$$, $$K^{-1}$$ $$\varkappa$$, $$\frac{W}{m\cdot K}$$ $$\rho$$, $$\frac{kg}{m^3}$$ $$c\cdot 10^{-3}$$, $$\frac{J}{kg\cdot K}$$ $$R\cdot 10^{-6}$$, $$\Omega\cdot m$$
20 198 7820 0.169
100 196 12.2 51 0.47 0.219
200 191 13 49 0.483 0.292
300 186 13.7 46 0.381
400 163 14.3 43 0.521 0.488
500 14.7 40 0.571 0.601
600 15 36 0.758
700 15.2 32 0.925
800 26

Mechanical properties at 20 °C

Rolling Standard Size, mm Tension Classifiers $$\sigma _{U}$$, $$MPa$$ $$\sigma_{P}$$, $$MPa$$ $$\epsilon_L$$, % $$\psi$$, % Treatment
Sheet 4–14 heat-treated 390–540 26
Round GOST 10702-78 calibrated 540 50 Annealing
Metal rolling GOST 1050-88 < 80 450 275 23 50 Normalization
Metal rolling GOST 1050-88 cold-work 540 7 40
Metal rolling GOST 1050-88 annealing 410 19 50
Tape annealing 340–590 18
Tape cold-work 540–880

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Sheet heat-treated 0–0
Round GOST 10702-78 hot rolling 0–0
Metal rolling GOST 1050-88 calibrated, cold-work 217
Metal rolling GOST 1050-88 annealing, calibrated 0–0
Sheet fat 0–0

Technological Properties

Weldability Flake Susceptibility Propensity to temper brittleness
no limits not sensitive not inclined

Critical point temperatures

Ac1, K Ac3(Acm), K Ar3(Arcm), K Ar1, K
735 835 825 680

Analogues

USA Germany
M1025 1.1158 (C25E)

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