4340 Steel [AMS 6484]

AMS 6484 chromium-nickel-molybdenum alloy is a widely used deep-hardening constructional steel.

Remarkable Ductility

It is used at a variety of strength levels and at each level possesses remarkable ductility and toughness. With its high alloy content uniform hardness is developed by heat treatment in relatively heavy sections. High fatigue strength makes E-4340 ideal for highly stressed parts. It maintains its strength and hardness at elevated temperatures. This grade is available as electric furnace vacuum degassed steel to meet the high aircraft quality standards of AMS 2301. Thus, it is suitable for the fabrication of parts, which may be subjected to magnetic particle inspection.

Aerospace Sector

This grade is also available as a premium aircraft quality product. The regular aircraft quality material is re-melted in a vacuum using consumable electrode practice. This results in a much cleaner steel meeting the magnetic particle test requirements of AMS-2300 and insures a steel of the highest quality with excellent transverse ductility and toughness at high strength levels.

Suitability

Aircraft landing gear, engine components, crankshafts, axles. Intended for parts with sections 3 ½” or less in thickness at time of heat treatment, which require a through-hardening steel capable of developing minimum hardness of Rockwell “C” 30. Premium aircraft quality is intended for use in the manufacturing of highly stressed parts at higher strength levels, such as 260/280 ksi and where a much cleaner steel is desired.

Typical Applications

Commercial applications for this engineering material include: