Heat-resistant structural steels
Heat-resistant structural steels are structural steels designed to retain useful strength and dimensional stability at elevated temperatures. They are used for load-bearing components in hot-service equipment where mechanical performance must be maintained during heating.
| Grade | Material no. | C | Si | P | S | Mn | Mo |
|---|---|---|---|---|---|---|---|
| 22CrMo4-4 | 1.7350 | 0,19-0,26 | 0,15-0,40 | 0,035 | 0,035 | 0,50-0,80 | 0,40-0,50 |
| 12CrMo9-10 | 1.7375 | 0,10-0,15 | ≤0,30 | 0,015 | 0,01 | 0,30-0,80 | 0,90-1,10 |
| 1.7380 | 1.7380 | 0,08-0,14 | ≤0,50 | 0,02 | 0,01 | 0,40-0,80 | 0,90-1,10 |
| 11CrMo9-10 | 1.7383 | 0,08-0,15 | ≤0,50 | 0,02 | 0,01 | 0,40-0,80 | 0,90-1,10 |
| 21CrMoV5-7 | 1.7709 | 0,17-0,25 | ≤0,40 | 0,025 | 0,03 | 0,40-0,80 | 0,55-0,80 |
| 40CrMoV4-6 | 1.7711 | 0,36-0,44 | ≤0,40 | 0,025 | 0,03 | 0,45-0,85 | 0,50-0,65 |
| 1.7715 | 1.7715 | 0,10-0,18 | ≤0,40 | 0,025 | 0,015 | 0,40-0,70 | 0,50-0,70 |
| 24CrMoV5-5 | 1.7733 | 0,20-0,28 | 0,15-0,35 | 0,035 | 0,035 | 0,30-0,60 | 0,50-0,60 |
| 21CrMoV5-11 | 1.8070 | 0,17-0,25 | 0,30-0,60 | 0,035 | 0,035 | 0,30-0,60 | 1,00-1,20 |
| 18MnMoV5-2 | 1.8812 | ≤0,20 | 0,20-0,50 | 0,03 | 0,025 | 1,00-1,50 | 0,10-0,30 |
| A 516 Grade 70 | 1.9441 | ≤0,27 | 0,15-0,40 | 0,035 | 0,035 | 0,85-1,20 | — |
| A 105 | 1.9443 | ≤0,35 | 0,10-0,35 | 0,035 | 0,04 | 0,60-1,05 | ≤0,12 |
Standards covering this category
24Property ranges
18| Property | Unit | Min | Max | Grades |
|---|---|---|---|---|
| ReH | N/mm² | 210 | 470 | 13 |
| Rm | N/mm² | 350 | 880 | 18 |
| Re | N/mm² | 205 | 735 | 8 |
| A | % | 17 | 32 | 6 |
| A5 | % | 14 | 25 | 8 |
| Z | % | 35 | 67 | 4 |
| KCU | kJ/m² | 294 | 2700 | 8 |
| HB | — | 123 | 321 | 4 |
| rho | g/cm³ | 7.49 | 7.87 | 62 |
| E | GPa | 151 | 217 | 4 |
| alpha | 10^-6/K | 11.2 | 14.9 | 4 |
| lambda | W/(m·K) | 28 | 51 | 4 |
| cp | J/(kg·K) | 462 | 703 | 3 |
| rho_el | nΩ·m | 200 | 1219 | 3 |
| Ac1 | °C | 724 | 760 | 4 |
| Ac3 | °C | 840 | 890 | 4 |
| Ar3 | °C | 760 | 825 | 3 |
| Ar1 | °C | 680 | 730 | 3 |
Derived from 62 grades in this category with a recorded value.
Composition range
19| Property | Unit | Min | Max | Grades |
|---|---|---|---|---|
| B | % | 0.0008 | 0.006 | 3 |
| C | % | 0.06 | 0.77 | 62 |
| N | % | 0.009 | 0.02 | 19 |
| Al | % | 0.01 | 0.06 | 20 |
| Si | % | 0.08 | 1 | 62 |
| P | % | 0.012 | 0.045 | 62 |
| S | % | 0.005 | 0.045 | 62 |
| Ti | % | 0.03 | 0.06 | 7 |
| V | % | 0.02 | 0.45 | 30 |
| Cr | % | 0.12 | 2.5 | 50 |
| Mn | % | 0.3 | 3.2 | 62 |
| Co | % | 0.03 | 0.03 | 1 |
| Ni | % | 0.12 | 1.3 | 37 |
| Cu | % | 0.12 | 0.8 | 32 |
| As | % | 0.025 | 0.025 | 1 |
| Nb | % | 0.01 | 0.05 | 13 |
| Mo | % | 0.08 | 1.2 | 58 |
| Sn | % | 0.011 | 0.025 | 2 |
| Ta | % | 0.03 | 0.03 | 1 |
Derived from 62 grades in this category with a recorded value.
Heat treatment
6| Operation | MinTemperature (°C) | MaxTemperature (°C) | Grades |
|---|---|---|---|
| tempering | 650 | 730 | 3 |
| normalizing | 900 | 960 | 3 |
| isothermal_annealing | — | — | 2 |
| quenching | — | — | 2 |
| quench_and_temper | — | — | 1 |
| annealing | 650 | 705 | 1 |