Alloy steel with chrome molybdenum vanadium, generally used for boilers, steel that resists at high temperatures up to about 550° C, generally used for particulars and shafts for turbines, nuts and tubes.
Standard Reference: EN 10269: 2013 (Bright products)
| EUROPE | ITALY | GERMANY | FRANCE | UK | USA | ||
|---|---|---|---|---|---|---|---|
| EN 10269: 2003 | (UNI 7845-78) | (DIN 17200-86) | (NF A 35-552-86) | (BS 970 pt.3-96) | ASTM A 29 | ||
| Grade | N° | Werkstoff | N° | ||||
| 21CrMoV5-7 | 1.7709 | - | - | - | - | - | - |
| C | Si/max | Mn | P/max | S | Cr | Mo | B | Ni/max | Al/max | V |
|---|---|---|---|---|---|---|---|---|---|---|
| 0,17÷0,25 | 0,40 | 0,40÷0,80 | 0,025 | ≤ 0,030 | 1,20÷1,50 | 0,55÷0,80 | 0,0010÷0,0050 | 0,60 | 0,030 | 0,20÷0,35 |
| Size (mm) |
Treated to improve shearability (+S) |
Spheroidized annealed (+AC) |
Quenched and tempered (+QT) |
||||
|---|---|---|---|---|---|---|---|
| HB max to condition | Rp0,2 (MPa) min |
Rm (MPa) min |
A5 (%) min |
Z (%) min |
KV (J) min + 20°C |
||
| d≤160 | 255 | 229 | 550 | 700÷850 | 16 | 60 | 63 |
| Operation | °C |
|---|---|
| Hot forgings deformation | 850÷1150 |
| annealed to achieve spheroidized carbides | 680÷720 |
| Soft annealing | 650÷730 |
| Quenching in water or oil | 880÷950 |
| Tempering | 660÷740 |
