50HN
Rolls for hot rolling, shafts, gears, gear wheels, tires, crankshafts, connecting rods, bolts, exhaust valves and other major important parts.
Classification
Country |
Section |
Category |
CIS, Russia, Ukraine |
Structural steel |
Alloyed structural steel |
Chemical composition
Standard |
Fe, % |
Si, % |
Mn, % |
Cr, % |
Cu, % |
Ni, % |
P, % |
C, % |
S, % |
GOST 4543-71 |
95.77–97.42 |
0.17–0.37 |
0.5–0.8 |
0.45–0.75 |
< 0.3 |
1–1.4 |
< 0.035 |
0.46–0.54 |
< 0.035 |
Information on suppliers
Physical characteristics
Temperature, °C |
$$\alpha\cdot 10^{6}$$, $$K^{-1}$$ |
$$\varkappa$$, $$\frac{W}{m\cdot K}$$ |
$$\rho$$, $$\frac{kg}{m^3}$$ |
$$c\cdot 10^{-3}$$, $$\frac{J}{kg\cdot K}$$ |
20 |
|
|
7860 |
|
100 |
11.8 |
43 |
|
0.5 |
200 |
|
40 |
|
0.51 |
300 |
12.3 |
39 |
|
0.56 |
400 |
13.4 |
38 |
|
0.63 |
500 |
14 |
37 |
|
0.7 |
600 |
|
36 |
|
0.8 |
700 |
|
32 |
|
0.91 |
800 |
|
23 |
|
0.65 |
900 |
|
24 |
|
0.61 |
1000 |
|
|
|
0.7 |
Mechanical properties at 20 °C
Rolling |
Standard |
Size, mm |
Tension |
Classifiers |
$$\sigma _{U}$$, $$MPa$$ |
$$\sigma_{P}$$, $$MPa$$ |
$$\epsilon_L$$, % |
$$\psi$$, % |
$$KCU\cdot 10^{3}$$, $$\frac{J}{m^2}$$ |
Treatment |
Rod |
GOST 4543-71 |
25 |
|
|
1080 |
885 |
9 |
40 |
490 |
Tempering 820 ° C, the water, leave 530 ° C, the water |
Brinell hardness number
Technological Properties
Weldability |
Flake Susceptibility |
Propensity to temper brittleness |
Not applicable for welded structures |
sensitive |
inclined |
Critical point temperatures
Ac1, K |
Ac3(Acm), K |
Ar3(Arcm), K |
Ar1, K |
Mn, K |
735 |
755 |
690 |
660 |
300 |
Analogues
Standards
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 |
$$\alpha\cdot 10^{6}$$ |
$$K^{-1}$$ |
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) |
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 |
$$KCU\cdot 10^{3}$$ |
$$\frac{J}{m^2}$$ |
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 |
|