4340
(UNS G43400) Low alloy nickel-chromium-molybdenum steel with excellent hardenability. Quench and tempering heat treatments yield good combinations of strength and toughness.
Chemistry
| Element |
C |
Mn |
P |
S |
Si |
Cr |
Ni |
Cu |
Mo |
| 4340 |
0.38-0.43% |
0.65-0.85% |
0.025% max |
0.025% max |
0.15-0.35% |
0.70-0.90% |
1.65-2.00% |
0.35% max |
0.20-0.30% |
Physical Constants
| Density | 0.284 lbs/in3 |
| Density | 7.84 g/cm3 |
Heating
| Forging | 2250ºF-1950ºF |
| Annealing | 1300ºF slow cool / furnace cool |
| Tempering | 400ºF-1200ºF depending on desired strength |
| Normalizing | 1600ºF-1700ºF air cool |
| Austenize | 1475ºF-1575ºF quench in oil |
Viking Forging Parameters
| Rings | 24" O.D. X 6" long | 500 lbs. |
| Sleeves | 16" O.D. X 12" long | 500 lbs. |
| Disks | 26" O.D. X 6.5" long | 500 lbs. |
| Round Bar | 12" Dia. X 96" long | 2600 lbs. |
| Square/Rectangular Bar | 12" square X 96" long | 2600 lbs. |
| Blocks | 14" X14" x 14" | 750 lbs. |
| Shafts | 12" Dia max 96" long | 2600 lbs. |
