AMS 6257
Alloy Steel Grade: AISI 4340 MOD 300M
Product Forms: Steel, Chrome-Nickel-Molybdenum (8740) Bars and Re-forging Stock (Aircraft Quality)
Condition: Consumable Electrode Vacuum Re-melted Normalized and Tempered
Scope: This specification covers a premium aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stock.
Product availability:
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DISCLAIMER: Alloy data sheets are for reference only, not for design purposes.
| Chemical Composition | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| C 0.38 – 0.43% Max | Mn 0.65 – 0.90% | Si 1.45 – 1.80% | P 0.010% Max | S 0.008% | |||||
| Cr 0.70 – 0.95% | Ni 1.65 – 2.00% | Mo 0.30 – 0.50% | V 0.05 – 0.10% | Cu 0.35% Max | |||||
All service center locations are AS9100 & ISO9001 accredited.
Birmingham, UK and Meerbusch, Germany service center locations are AS9100, AS9120 & ISO9001 accredited.
T.I. Approvals:
Plus a wide range of approvals from most leading OEM’s across Aerospace, Medical, Industrial, and Oil and Gas markets.