D6AC is a low alloy vacuum melted steel containing several other elements. The hardenability of this alloy is better than 4340 and can be heat treated to strengths ranging from 180 to 260 ksi. Typical applications are for aircraft landing gear, axles or shafts and similar uses that require very good combination of fatigue strength and toughness.
| Specification | Description |
|---|---|
| AMS 6431 | Steel Bars and Forgings. Vacuum Melted |
| AMS 6439 | Steel Plate Sheet, Strip, and Coil. Vacuum Melted. |
| MIL-S-8949 | Steel Bars, Plates, and Forgings |