A20
Substitute: A12.
Carbon Sulfur Steel
Small parts of machines and appliances, lightly loaded parts of complex configuration, which are requirements of high dimensional accuracy and surface quality after carburizing and cyanide — lightly loaded parts, which are requirements of high wear resistance and surface quality.
Classification
| Country |
Section |
Category |
| CIS, Russia, Ukraine |
Structural steel |
Improved machinability structural steel |
Chemical composition
| Standard |
Fe, % |
Si, % |
Mn, % |
Cu, % |
P, % |
C, % |
S, % |
|---|
| GOST 1414-75 |
97.94–98.9 |
0.15–0.35 |
0.7–1 |
< 0.25 |
< 0.06 |
0.17–0.25 |
0.08–0.15 |
Information on suppliers
Physical characteristics
| Temperature, °C |
$$\rho$$, $$\frac{kg}{m^3}$$ |
|---|
| 20 |
7840 |
Mechanical properties at 20 °C
| Rolling |
Standard |
Size, mm |
Tension |
Classifiers |
$$\sigma _{U}$$, $$MPa$$ |
$$\psi$$, % |
d5, % |
Treatment |
|---|
| Rental hot rolled. |
GOST 1414-75 |
|
|
hot rolling |
450 |
30 |
20 |
|
| Rental calibrated. Hardened. |
GOST 1414-75 |
|
|
calibrated, cold-work |
530 |
|
7 |
|
Brinell hardness number
| Rolling |
Standard |
Classifiers |
Value, HBW |
| Rental hot rolled. |
GOST 1414-75 |
hot rolling |
168 |
| Rental calibrated. Hardened. |
GOST 1414-75 |
calibrated, cold-work |
217 |
Technological Properties
| Weldability |
Flake Susceptibility |
Propensity to temper brittleness |
|---|
| Not applicable for welded structures |
sensitive |
not inclined |
Critical point temperatures
| Ac1, K |
Ac3(Acm), K |
Ar3(Arcm), K |
Ar1, K |
|---|
| 735 |
866 |
840 |
685 |
Analogues
| USA |
Germany |
Bulgaria |
|---|
| 1120 |
22SPb20 |
А20 |
Standards
Description of chemical elements
| Element |
Units of measurement |
Description |
| Fe |
% |
Iron |
| Si |
% |
Silicon |
| Mn |
% |
Manganese |
| Cu |
% |
Copper |
| P |
% |
Phosphorus |
| C |
% |
Carbon |
| S |
% |
Sulfur |
Description of physical characteristics
| Parameter |
Units of measurement |
Description |
| $$\rho$$ |
$$\frac{kg}{m^3}$$ |
The density of the material |
Description of mechanical properties
| Parameter |
Units of measurement |
Description |
| d5 |
% |
Elongation at break |
| $$\sigma _{U}$$ |
$$MPa$$ |
Ultimate tensile strength |
| $$\psi$$ |
% |
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 |
|