4340 VAC-ARC steel is a low alloy, nickel-chromium-molybdenum steel capable of being heat treated to high strength levels. The alloy has a good combination of ductility, toughness and strength along with high hardenability and better depth of hardening than chrome-moly 4140 type alloys. 4340 steel is produced by the consumable electrode vacuum arc remelting process to provide optimum cleanliness and preferred ingot structure.
