Aircraft Steel 9-4-30 Vac Melt (AMS 6526)

Technical Data Sheet


Chemical Composition Limits
Weight% C Mn Si Cr V Mo Ni Co
9-4-30 Vac Melt N&T 0.30 0.30 0.10 1.00 0.10 1.00 7.50 4.50

Alloy 9-4-30 Vac Melt N&T (LESCALLOY HP 9-4-30 VAC ARC ®) is a low alloy, high strength steel with a high nickel and cobalt content to promote toughness. Alloy 9-4-30 Vac Melt N&T was designed to have high hardenability together with good weldability and excellent fracture toughness. Alloy 9-4-30 Vac Melt N&T is used in aircraft structural components, rocket motor cases, armor plate, pressure vessels and gears.

Alloy 9-4-30 Vac Melt N&T (LESCALLOY HP 9-4-30 VAC ARC ®) is available in bar (round bar).  For all stock availability contact Sales.

Typical Mechanical Properties


Material RCS Billet Size mm
0.2 % Yield Strength (Mpa) Ultimate Tensile Strength (Mpa) % Elongation % Reduction of Area
LESCALLOY HP 9-4-30 VAC ARC ® 343 1300 1580 14.7 50.3
LESCALLOY HP 9-4-30 VAC ARC ® 343 1260 1590 14.0 45.9
LESCALLOY HP 9-4-30 VAC ARC ® 146 1340 1600 15.0 52.5
LESCALLOY HP 9-4-30 VAC ARC ® 146 1310 1590 15.0 51.7
Actual center transverse mechanical properties

AMS 6526
MIL-STD-2154 Cl A
UNS K91283
BMS-7-182 Type 2
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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.