high temperature boiler steels for energy industries
| Elements | Min.（≥） | Max.（≤） | Similar | Remarks |
|---|---|---|---|---|
| C | 0.17 | 0.25 | ||
| Mn | 0.30 | 0.50 | ||
| Si | 0.30 | 0.60 | ||
| P | - | 0.035 | ||
| S | - | 0.035 | ||
| Cr | 1.20 | 1.50 | ||
| Ni | - | 0.60 | ||
| Mo | 1.00 | 1.20 | ||
| V | 0.25 | 0.35 |
21CMoV5-7 alloy structural steel and its 1.7709 replacement alloys belong to the group of high temperature boiler steels for energy industries. They are used in the production of components/subassemblies for the power industry, working at the temperatures up to 550 oC for small parts and for large forgings. The main applications of these grades of steel are rotors of steam turbines, rotor blades, shaft forgings, reservoirs and covers for up to 550 ℃ temperatures, nuts, tubes for high temperatures up to 540 ℃.
| Proof strength Rp0.2 (MPa) |
Tensile strength Rm (MPa) |
Impact energy KV (J) |
Elongation at fracture A (%) |
Reduction in cross section on fracture Z (%) |
As-Heat-Treated Condition | Brinell hardness (HBW) |
|---|---|---|---|---|---|---|
| 721 (≥) | 495 (≥) | 44 | 14 | 12 | Solution and Aging, Annealing, Ausaging, Q+T,etc | 312 |
| Property | Density kg/dm3 |
Temperature T °C/F |
Specific heat J / kgK |
Thermal conductivity W/mK |
Electric resistance µΩ·cm |
Modulus of elasticity kN/mm2 |
Expansion rate |
|---|---|---|---|---|---|---|---|
| 771 (≥) | 819 (≥) | 43 | 24 | 14 | Solution and Aging, Annealing, Ausaging, Q+T,etc | 112 | |
| Temp. °C/°F |
Creep strain limit (10000h) (Rp1,0) N/mm2 |
Creep rupture strength (10000h) (Rp1,0) N/mm2 |
|||||
| 783 | 529 | 423 |
We can customize the production of 21CMoV5-7 grade, contact us for the best solution.
–sales@specificsteel.com