25L
bed mills, pulleys, beams, pistons, boxes, cover cylinders, plate flatness, frame roller tables and carts, trough, bearing housings, parts welded-cast structures and other parts operating at temperatures from -40 to 450 ° C under pressure.
Classification
Country |
Section |
Category |
CIS, Russia, Ukraine |
Steels and alloys for castings |
Ordinary steel for castings |
Chemical composition
Standard |
Fe, % |
Si, % |
Mn, % |
P, % |
C, % |
S, % |
GOST 977-88 |
98.16–99.13 |
0.2–0.52 |
0.45–0.9 |
< 0.06 |
0.22–0.3 |
< 0.06 |
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 |
|
51 |
7830 |
|
100 |
11.5 |
76 |
|
0.47 |
200 |
12.9 |
65 |
|
0.483 |
300 |
13 |
44 |
|
|
400 |
13.2 |
38 |
|
0.525 |
500 |
13.5 |
|
|
|
600 |
|
|
|
0.571 |
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 |
Castings |
GOST 977-88 |
< 100 |
|
|
441 |
235 |
19 |
30 |
392 |
Normalization of 880-900 ° C, 610-630 ° C and Holidays |
Castings |
GOST 977-88 |
|
|
|
491 |
294 |
22 |
33 |
343 |
Tempering 870-890 ° C, 610-630 ° C and Holidays |
Brinell hardness number
Rolling |
Standard |
Classifiers |
Value, HBW |
Alloy |
|
|
124–207 |
Casting and technological parameters
linear shrinkage, % |
2.2–2.3 |
Technological Properties
Weldability |
Flake Susceptibility |
Propensity to temper brittleness |
Boundedly welded |
not sensitive |
not inclined |
Critical point temperatures
Ac1, K |
Ac3(Acm), K |
Ar3(Arcm), K |
Ar1, K |
735 |
840 |
824 |
680 |
Heat Treatment Modes
Treatment |
Normalization 880 - 900 ° C, Vacation 610 - 630 ° C |
Tempering 870 - 890 ° C, Vacation 610 - 630 ° C |
Analogues
Standards
Description of chemical elements
Element |
Units of measurement |
Description |
Fe |
% |
Iron |
Si |
% |
Silicon |
Mn |
% |
Manganese |
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 |
Description of the casting and technological parameters
Parameter |
Units of measurement |
Description |
linear shrinkage |
% |
The difference between model dimensions and the model casting |
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 |
|