15X25T steel
15X25T Steel
Steel 15X25T: Handbook 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 brand — Steel 15X25T.
General information on steel 15X25T
| Grade substitute |
| steel 12Х18Н10Т |
| Delivery type |
| Sheet 15h25T, 15x25T pipe, 15x25T circle, 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 thick GOST 7350−77. Sheet GOST 5582−75 thin. GOST 4405−75, GOST 103−76. Forgings and forged blanks GOST 1133−71. GOST 9941−81 pipes, GOST 9940−81. |
| Application |
| Recommended for welded structures not exposed to impact loads at operating temperature not lower than -20°С. Pipes for heat-exchange equipment operating in aggressive environments. Equipment, parts, thermocouple sheaths, spark plug electrodes, heat exchangers. The steel is heat-resistant up to 1100 °C, corrosion-resistant of ferrite class. |
Chemical composition of steel 15X25T
| Chemical element | % |
| Silicon (Si), not more | 1.0 |
| Manganese (Mn), not more than | 0.8 |
| Copper (Cu), not more than | 0.30 |
| Nickel (Ni), not more than | 0.6 |
| Sulfur (S), not more than | 0.025 |
| Titanium (Ti) | 0.5−0.9 |
| Carbon ©, not more than | 0.15 |
| Phosphorus (P), not more | 0.035 |
| Chrome (Cr) | 24.0−27.0 |
Mechanical properties of steel 15X25T
| Heat treatment, delivery condition | Section, mm | σ0, 2, MPa | σB, MPa | δ5, % | ψ, % |
| Rods. Annealed at 730−770°C, air or water or without heat treatment | 60 | 295 | 440 | 20 | 45 |
| Hot- or cold-rolled sheets. Annealing or tempering 740−780°C, water (crosswise samples) | >4 | 440 | 14 | ||
| Hot- or cold-rolled sheets. Annealing or tempering 740−780°C (cross samples) | <3,9 | 530 | 17 | ||
| Seamless hot-deformed pipes without heat treatment. | 3,5−32 | 441 | 17 | ||
| Cold-rolled and heat-treated seamless pipes | 0,2−22 | 461 | 17 |
Mechanical properties at elevated temperatures
| t test,°C | σB, MPa | δ5, % | ψ, % | |||||||||||
| Rods… Annealing at 760−780°C, cooling in water. | ||||||||||||||
| 700 | 77 | 48 | 93 | |||||||||||
| 800 | 26 | 104 | 99 | |||||||||||
| 900 | 19 | 153 | 99 | |||||||||||
| 1000 | 11 | 148 | 100 | |||||||||||
| 1100 | 8 | 139 | 99 | |||||||||||
Mechanical properties depending on degree of plastic deformation
| Heat treatment, delivery condition | σB, MPa | δ5, % |
| Without deformation | 450 | 32 |
| Degree of deformation — 10% | 600 | 15 |
| Degree of deformation — 20% | 700 | 10 |
| Degree of deformation — 30% | 760 | 8 |
| Degree of deformation — 40% | 800 | 7 |
| Degree of deformation — 50% | 840 | 6 |
| Degree of deformation — 60% | 860 | 5 |
Mechanical properties in the long term strength test
| Creep limit, МPa | Creep rate, %/h | t test,°C | Ultimate long-term strength, MPa | Test duration, h | t test, h |
| 12 | 1/1000 | 700 | 18 | 1000 | 700 |
| 8 | 1/10000 | 700 | 8 | 1000 | 800 |
| 3 | 1/1000 | 875 | 4 | 1000 | 875 |
| 2 | 1/10000 | 875 | 3 | 1000 | 1000 |
Technological properties of steel 15X25T
| Forging temperature |
| Beginning 1160, end 800. |
| Weldability |
| hardly weldable. When automatic welding is recommended to use wire Sv-07H25N12Tu, Sv-13H25N18 with flux AN-26. In the case of manual welding good plasticity electrodes with a wire of steel Sv-13X25N18 (Type 03L-9) or with a wire Sv-07X25N13 type EA-2 and EA-2B. Heating at 150−200°C and subsequent heat treatment, tempering at 600 °C are necessary. |
| Cutability |
| In the annealed condition at NV 149−163 Kυ of solid. = 0,9, Kυ b.st. = 0,6. |
| Tendency to temperability |
| is inclined in the interval of 450−520 С. |
Corrosion properties of steel 15X25T
| Medium | Temperature of test, °C | Test duration, h | Depth, mm/year |
| 6% HNO3 solution | 20 | 640 | 0.001 |
| 40% HNO3 solution | 0 | 640 | 0.001 |
| 85% H3PO4 solution | 0 | 480 | 0,01 |
Heat resistance of 15X25T steel
| Medium | Temperature, °C | Test duration, h | Depth, mm/year | Resistance group or grade |
| Air | 850 | 0,175 | 6 | |
| Air | 950 | 0,294 | 6 | |
| Air | 1050 | 0,490 | 6 | |
| Clean air | 900 | 500 | 0,39 | 6 |
| 1.5% SO2+clean air | 900 | 500 | 0,54 | Reduced resistance |
Physical properties of steel 15X25T
| Test temperature,°C | 20 | 100 | 200 | 300 | 400 | 500 | 600 | 700 | 800 | 900 |
| Modulus of normal elasticity, E, GPa | 204 | 200 | 197 | 189 | 176 | 164 | 140 | 124 | 119 | 109 |
| Steel density, pn, kg/m3 | 7600 | |||||||||
| Thermal conductivity coefficient W/(m — °C) | 17 | |||||||||
| Electrical resistivity (p, nominal value — m) | 710 | |||||||||
| 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) | 10.1 | 10.7 | 11.0 | 11.2 | 11.3 | |||||
| Specific heat capacity (C, J/(kg -°C)) | 462 |
