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. |