Aircraft Steel HY-TUF Vac Melt (AMS 6418 / AMS 6425)

Technical Data Sheet


Chemical Composition Limits
Weight% C Mn Si Ni Cr Mo
LESCALLOY HY-TUF VAC-ARC® 0.25 1.35 1.50 1.80 0.30 0.40

LESCALLOY HY-TUF VAC ARC® is a high strength low alloy steel. within the tensile range 220/240 ksi (1517/1655MPa) LESCALLOY HY-TUF VAC ARC has good ductility, fracture toughness and impact strength. HY-TUF is most commonly used for aircraft landing gear, flap tracks and other structural applications.

LESCALLOY HY-TUF VAC ARC® is available in bar (round bar).  For all stock availability contact Sales.

Typical Mechanical Properties


Material Orinentation Ultimate Tensile Strength (Mpa) 0.2 % Yield Strength (Mpa) % Elongation % Reduction of Area
LESCALLOY HY-TUF VAC ARC® Transverse 1517 1276 5 30
Typical Transverse specification limits after the following heat treatments
1725°F (940 °C), one hour, air cool
1600°F (871°C), one hour, oil quench
550°F (288°C), two hours, air cool

AMS 6418
AMS 6425 (Vac Melt)
AMS 2300
AMS 2301
AMS 2304
UNS K32550
DMS-1841 Grd B
DMS-1841 Grd A
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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.