Steel 20X25H20C2
Steel 20X25H20C2
Steel 20X25H20C2: a classifier of steels and alloys. Below is systematized information on the purpose, chemical composition, types of supply, substitutes, critical point temperature, physical, mechanical, technological and foundry properties for the grade — Steel 20X25N20C2.
General information on steel 20X25H20C2
| Delivery type |
| Sheet 20х25Н20с2, bars, including shaped: GOST 5949−75, GOST 2590−71, GOST 2591−71, GOST 2879−69. Calibrated bar GOST 7417−75, GOST 8559−75, GOST 8560−78. Grinded rod and silver GOST 14955−77. Sheet thin GOST 5582−75, GOST 19903−74, GOST 19904−74. Strip GOST 4405−75, GOST 103−76. Forgings and forged blanks GOST 1133−71. |
| Application |
| The parts of the furnaces operating at temperatures up to 1100 °C in the air and hydrocarbon atmospheres. Heat-resistant steel of the outtense class. |
Chemical composition of steel 20X25H20S2
| Chemical element |
% |
| Vanadium (V), not more |
0.2 |
| Tungsten (W), not more |
0.2 |
| Silicon (Si) |
2.0−3.0 |
| Manganese (Mn), not more than |
1.5 |
| Copper (Cu), not more than |
0.30 |
| Molybdenum (Mo), not more than |
0.30 |
| Nickel (Ni) |
18.0−21.0 |
| Sulfur (S), not more than |
0.020 |
| Titanium (Ti), not more than |
0.2 |
| Carbon ©, not more than |
0.20 |
| Phosphorus (P), not more than |
0.035 |
| Chrome (Cr) |
24.0−27.0 |
Mechanical properties of steel 20X25H20C2
| Heat treatment, delivery condition |
Section, mm |
σ0.2, MPa |
σB, MPa |
δ5, % |
ψ, % |
| Rods. Hardening 1100−1150°C, air or water. |
60 |
295 |
590 |
35 |
50 |
| Hot- and cold-rolled sheets. Hardened 1050−1100°C, water or air. (crosswise samples) |
<3,9 |
|
490 |
35 |
|
Mechanical properties at elevated temperatures
| t test,°C |
σ0, 2, MPa |
σB, MPa |
δ5, % |
ψ, % |
| 500 |
255 |
520 |
30 |
47 |
| 600 |
210 |
490 |
35 |
50 |
| 700 |
165 |
320 |
40 |
55 |
| 800 |
110 |
195 |
50 |
63 |
Mechanical properties in the long term strength test
| Creep strength, MPa |
Creep rate, %/h |
t test,°C |
Ultimate long-term strength, MPa |
Test duration, h |
t test, h |
| 4 |
0.5/1000 |
875 |
37 |
100 |
875 |
| 5 |
1/1000 |
875 |
22 |
1000 |
875 |
| 10 |
1/1000 |
1000 |
20 |
100000 |
800 |
|
|
|
7 |
100000 |
900 |
Technological properties of steel 20X25H20C2
| Forging temperature |
| Beginning 1170, end 850. Cooling in the air. |
| Tendency to tempering |
| inclined in the range of 600−800 C due to the formation of b-phase (GOST 5632−72). |
Heat resistance of steel 20X25H20C2
| Medium |
Temperature,°C |
Depth, mm/year |
Resistance group or grade |
| Air |
875 |
0,117 |
6 |
| Air |
1050 |
0,476 |
6 |
| Air |
1200 |
1,404 |
Low-resistant |
Physical properties of steel 20Х25Н20С2
| Test temperature,°C |
20 |
100 |
200 |
300 |
400 |
500 |
600 |
700 |
800 |
900 |
| Steel density, pn, kg/m3 |
7720 |
7680 |
|
|
|
|
|
|
7440 |
7390 |
| Heat transfer coefficient W/(m -°C) |
|
15 |
|
|
|
22 |
24 |
25 |
27 |
29 |
| Test temperature,°C |
20−100 |
20−200 |
20−300 |
20−400 |
20−500 |
20−600 |
20−700 |
20−800 |
20−900 |
20−1000 |
| Coefficient of linear expansion (a, 10−6 1/°C) |
16.1 |
|
|
|
|
17.8 |
17.8 |
18.1 |
18.5 |
18.8 |
