Aircraft Steel D-6AC Vac Melt (AMS 6431)

Technical Data Sheet


Chemical Composition Limits
Weight% C Si Mn Cr Ni Mo V
D-6AC Vac Melt N&T 0.46 0.25 0.75 1.10 0.60 1.00 0.10

Alloy D6AC Vac Melt N&T (LESCALLOY D6AC VAC ARC ®) is a medium carbon, low alloy steel. Alloy D6AC has ultra high strength and is designed for use in high strength structural applications (strength levels up to 280,000 psi). Alloy D6AC also is know for its high yield strength to tensile strength ratio, combined with good ductility. Due to alloy D6AC deep hardening characteristics it makes it applicable for fairly large sections.

Alloy D6AC Vac Melt N&T (LESCALLOY D6AC VAC ARC ®) is available in bar (round bar).  For all stock availability contact Sales.

Typical Mechanical Properties


Material Tempering Treatment
Ultimate Tensile Strength (Mpa) 0.2 % Yield Strength (Mpa) % Elongation % Reduction of Area Hardness HRC
LESCALLOY D6AC VAC ARC ® 316°C (600°F) 1931 1724 7 23 53
LESCALLOY D6AC VAC ARC ® 510°C (950°F) 1572 1345 7 25 46
Heat Treatment before temper. A ustenitized at 1650°F (899°C). Oil quenched and air cooled, or salt quenched at 400-425°F (204-218°C) for ten minutes and air cooled

AMS 6431
AMS 2300
UNS K24728
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Every effort is made to ensure that technical specifications are accurate. However, technical specifications included herein should be used as a guideline only. All specifications are subject to change without notice.