Heat-resistant ferritic steel X8CrTi25, 1.4746, X18CrN28, 1.4749 designed for operation in the environment of gases and fumes to 1000 ℃ acc. to PN-H-86022.
| Standard | Steel Grade | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Chemical Composition % | |||||||||
| C: | Mn: | Si: | P: | S: | Cr: | Ni: | Ti: | N: | |
| DIN | X8CrTi25 - X 8 CrTi 25 - 1.4746 | ||||||||
| <0.12 | <1.0 | <1.0 | <0.040 | <0.030 | 24.0 - 27.0 | - | <0.8 | - | |
| EN | X18CrN28 - X 18 CrN 28 - 1.4749 | ||||||||
| 0.15 - 0.20 | <1.0 | <1.0 | <0.040 | <0.015 | 26.0 - 29.0 | - | - | 0.15 - 0.25 | |
| PN | H25T | ||||||||
| <0.15 | <0.8 | <1.0 | <0.045 | <0.030 | 24.0 - 27.0 | <0.6 | 4xC <0.8 | - | |
| PN | H25 | ||||||||
| <0.20 | <0.8 | <1.0 | <0.035 | <0.030 | 23.0 - 27.0 | <0.7 | - | - | |
| GOST | 15Ch25T - 15Х25Т | ||||||||
| <0.15 | <0.8 | <1.0 | <0.035 | <0.025 | 24.0 - 27.0 | - | 5xC <0.9 | - | |
X8CrTi25, 1.4746, H25T - specification and application
X8CrTi25 / H25T is one of the better heat-resistant ferritic grades of steel with the addition of Titanium intended for operation at high temperatures, gas and flue gas environments up to 1000 ℃ right next to H24JS / 1.4762 / X10CrAlSi25. Usually supplied in the form of sheets, pipes and bars, it works best when working without significant loads and with a limited number of welded joints.
The prototype of the H25T was H25 not containing Titanium in chemical composition. Improvement of the grade by introducing the alloy addition was caused by unfavorable grain growth in the structure of the material during operation exceeding the temperature of 950 ℃.
The steel is characterized by sufficient weldability due to the requirement for additional thermal treatments during and after the process. Due to the ferritic structure, the products are not hardened and tempered - materials are delivered in an annealed condition +A. For welding of H25T materials are used austenitic electrodes ES-24-18.
H25T, and the equivalent of X8CrTi25 / 1.4746 is used in the production of annealing vessels, pyrite furnace scrapers, casement boxes, gutter furnaces, bottom plates, burner constructions, portions of gasifiers and gasifiers, grates for furnaces, pipes and installations in mines, parts of furnaces for power engineering and gas installations, furnace muffles, lead bath crucibles, and pyrometer shields.
Mechanical and physical properties - H25T, X8CrTi25, 1.4746
- Tensile strength, Rm: >440 MPa
- The yield point, Re: > 295 MPa
- Elongation (for bars and pipes), A: >20%
- Elongation (for sheets), A: >12%
- Heat capacity, cp20℃: 500 J * Kg-1 * K-1
- Thermal conductivity, λ: 16,5 W * m-1 * K-1
- Modulus of elasticity, E: 205 GPa
- Resistance, Ω: 0.67 mkOhm * m
Mechanical and physical properties of X18CrN28, 1.4749 in annealed condition +A according to EN 10297-2, EN 10088-1
- Tensile strength, Rm: >500 MPa
- The yield point, Re: > 280 MPa
- Elongation, A:> 15%
- Heat capacity, cp20℃: 500 J * Kg-1 * K-1
- Thermal conductivity, λ: 17.0 W * m-1 * K-1
- Resistance, Ω: 0.70 mkOhm * m
- Linear expansion coefficient, α: 10.0 * 10-6 K-1
Mechanical properties at elevated temperatures - X8CrTi25, 1.4746, H25T
| Properties (MPa) | Temperature (℃) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 500 | 550 | 600 | 650 | 700 | 750 | 800 | 850 | 900 | 1000 | |
| Creep limit, R1/1000 | - | - | 29.4 | - | 9.8 | - | 3.9 | - | 1.5 | 0.7 |
| Creep limit, R1/10000 | 78.4 | 34.3 | 17.6 | 8.8 | 3.9 | 1.9 | - | - | - | - |
| Creep limit, R1/100000 | 53.9 | 24.5 | 10.8 | 4.9 | 1.9 | 0.9 | - | - | - | - |
| Creep strength, Rz/1000 | - | - | 39.2 | 27.4 | 18.6 | 12.7 | 7.8 | 4.9 | - | - |
| Creep strength, Rz/10000 | 82.3 | 51.9 | 29.4 | 16.6 | 9.8 | 6.8 | 3.9 | 2.9 | - | - |
| Creep strength, Rz/100000 | 58.8 | 35.3 | 19.6 | 11.7 | 7.8 | 4.9 | 2.9 | 1.9 | - | - |
| Linear expansion coefficient, α | 11.3 | - | 11.4 | - | 11.7 | - | 12.2 | - | 12.7 | 13.4 |
Heat treatment processes:
- Annealing + A at 730 - 850℃ with cooling in water or air
- Hot plastic working at 1050 - 700 ℃ with air cooling
In the above-mentioned grades we deliver:
- Drawn and peeled bars H25T, X8CrTi25, 1.4746
- Heat-resistant sheets H25T, X8CrTi25, X18CrN28, 1.4749, 1.4746
- Rings and forged bars H25T, X8CrTi25, 1.4746
- Seamless tubs H25T, X18CrN28, 1.4749, 15Ch25T, 15Х25Т
Other grades designations:
15Ch25T, 15Х25Т, H25T, stal H25, X8CrTi25, X 8 CrTi 25, 1.4746, 1Cr25Ti, S12560, X18CrN28, 1.4749, X 8 CrN 28, 15H25T