D6AC is a medium carbon, low alloy, vacuum melted ultra high-strength steel primarily used for high strength structural applications requiring strength levels up to 280,000 PSI.
Its hardenability of this alloy is better than of AISI 4340. D6AC is able to reach strengths ranging from 180 to 260 KSI through heat treatment.
D6AC VAC-ARC Steel is produced by the consumable electrode vacuum arc remelting process to provide optimum cleanliness and preferred ingot structure.
Specifications:
- UNS K24728
- AMS 6431
- AMS 6438
- AMS 6432
- AMS 6439
- AMS-S-8949
- ASTM A579
- MIL-S-8949
- FMS-1011 (General Dynamics)
- GM-1013 (Grumman)
- STM 05-500 (Lockheed)
- LCM 05-2190 (Lockheed)
- TL-428 (MAN Technology)
Applications:
Aircraft landing gear, axles, shafts.
See link: https://www.cartech.com/globalassets/datasheet-pdfs/d6ac.pdf