20HGR
Gears, pinion shafts, worms, cam clutches, rollers, fingers, bushings and other improving or carburized parts operating under impact loads.
Classification
| Country |
Section |
Category |
| CIS, Russia, Ukraine |
Structural steel |
Alloyed structural steel |
Chemical composition
| Standard |
Fe, % |
Si, % |
B, % |
Mn, % |
Cr, % |
Ti, % |
Cu, % |
Ni, % |
P, % |
C, % |
S, % |
|---|
| GOST 4543-71 |
96.605–98.199 |
0.17–0.37 |
0.001–0.005 |
0.7–1 |
0.75–1.05 |
< 0.06 |
< 0.3 |
< 0.3 |
< 0.035 |
0.18–0.24 |
< 0.035 |
Information on suppliers
Physical characteristics
| Temperature, °C |
$$E\cdot 10^{9}$$, $$MPa$$ |
$$\alpha\cdot 10^{6}$$, $$K^{-1}$$ |
$$\rho$$, $$\frac{kg}{m^3}$$ |
|---|
| 20 |
207 |
|
7800 |
| 100 |
|
11.7 |
|
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 |
15 |
|
|
980 |
780 |
9 |
50 |
780 |
Tempering 880 ° C, oil, leave 200 ° C, air |
Brinell hardness number
| Rolling |
Standard |
Classifiers |
Value, HBW |
| Alloy |
GOST 4543-71 |
annealing |
197 |
Technological Properties
| Flake Susceptibility |
Propensity to temper brittleness |
|---|
| sensitive |
inclined |
Critical point temperatures
| Ac1, K |
Ac3(Acm), K |
Ar3(Arcm), K |
Ar1, K |
|---|
| 735 |
835 |
760 |
670 |
Standards
Description of chemical elements
| Element |
Units of measurement |
Description |
| Fe |
% |
Iron |
| Si |
% |
Silicon |
| B |
% |
Bor |
| Mn |
% |
Manganese |
| Cr |
% |
Chrome |
| Ti |
% |
Titan |
| 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 |
| $$\alpha\cdot 10^{6}$$ |
$$K^{-1}$$ |
Coefficient of thermal (linear) expansion (range 20°C–T) |
| $$\rho$$ |
$$\frac{kg}{m^3}$$ |
The density of the material |
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 |
Description of temperatures of critical points
| Parameter |
Units of measurement |
Description |
| Ac1 |
K |
|
| Ac3(Acm) |
K |
|
| Ar3(Arcm) |
K |
|
| Ar1 |
K |
|