Technical Data Sheet
Alloy Steel 300M VAR is similar to 4340 with the addition of vanadium and a higher silicon content. Alloy 300M offers a combination of toughness and ductility at high strength levels without an increased carbon content. Alloy 300M VAR is Vacuum arc-remelted for excellent purity. 300M can also be supplied dual certified to the British aerospace standard BS 5155.
| Chemical Composition Limits | |||||||||
| Weight% | C | Mn | P & S | Si | Cr | Ni | Mo | V | Cu |
| 300M VAR | 0.38 – 0.45 | 0.60-0.90 | 0.010 | 1.45-1.80 | 0.70-0.95 | 1.65-2 | 0.30-0.50 | 0.05-0.10 | 0.35 |
Typical Mechanical Properties
| Alloy | Condition | Tensile Strength ksi | Yield Strength ksi | Elongation % | Reduction of Area % | Hardness HB |
| Alloy AMS 6417 Bar | Normalised/Tempered | – | – | – | – | 311 max |
| Alloy AMS 6417 Bar | Hardened/ Tempered & Heat Treated | 270 | 220 | 8 | 30 | – |
| Alloy AMS 6419 Bar | Normalised/Tempered | – | – | – | – | 311 Max |
| Alloy AMS 6419 Bar | Normalised/Tempered & Heat Treated | 280 | 230 | 7 | 25 | – |
Heat Treatment
AMS 6419 / AMS 6417 / AMS 6257
| 300M Var | |
| Normalised | 1700°F / 1 hr |
| Austenitise | 1600°F / 1 hr |
| Quench | Oil |
| Double Temper | 575°F / 2 hr twice |
Availability
Alloy 300M VAR (AISI E4340) is available in Round Bar, Tube and Welding Wire. For all stock availability contact Sales.
Specifications
AISI E4340 Modified
AMS 6257 Bars / Forgings N&T
AMS 6417 Vac Melt Bars / tubes
AMS 6419 Bars / tubes
MIL-S-8844 Cl3
MIL-S-83135
BMS-7-26-Cl1
CE-0896
DMS-1935
GM-1012
LC-05-1190
BS S155