20kp

without heat treatment or after normalization — pipes, fittings, plugs, bolts, flanges, housing units and other details of the boiling steel, operating from -20 to 425 ° C; after carburizing and cyanide — the details of which require high surface hardness and low core strength (axles, fasteners, toes, stars, etc.).

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 98.185–99.58 < 0.07 0.25–0.5 < 0.25 < 0.3 < 0.3 < 0.08 < 0.035 0.17–0.24 < 0.04

Information on suppliers

Physical characteristics

Temperature, °C $$E\cdot 10^{9}$$, $$MPa$$ $$\alpha\cdot 10^{6}$$, $$K^{-1}$$ $$\varkappa$$, $$\frac{W}{m\cdot K}$$ $$\rho$$, $$\frac{kg}{m^3}$$ $$c\cdot 10^{-3}$$, $$\frac{J}{kg\cdot K}$$ $$R\cdot 10^{-6}$$, $$\Omega\cdot m$$
20 212
100 208 12.3 51 7834 0.486 0.219
200 203 13.1 49 7803 0.498 0.292
300 197 13.8 44 7770 0.514 0.381
400 189 14.3 43 7736 0.533 0.487
500 177 14.8 39 7699 0.555 0.601
600 163 15.1 36 7659 0.584 0.758
700 140 15.2 32 7617 0.636 0.925
800 26 7624 0.703 1.094
900 26 7600 0.703 1.135
1000 0.695

Mechanical properties at 20 °C

Rolling Standard Size, mm Tension Classifiers $$\sigma _{U}$$, $$MPa$$ $$\sigma_{P}$$, $$MPa$$ $$\epsilon_L$$, % $$\psi$$, % Treatment
Sheet termoobrabotki. GOST 4041-71 4–14 340–490 28
Trumpet GOST 10705-80 372 225 22
The steel is calibrated. GOST 10702-78 490 7 45
Band GOST 1577-93 6–60 380 225 27 55 Normalization

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Sheet termoobrabotki. GOST 4041-71 1270
Sheet annealed. GOST 1577-93 fat 1560

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
735 850 835 680

Analogues

USA Germany
M1023 1.1152 (Cq22)

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