This chromium nickel molybdenum alloy is primarily a carburizing grade capable of attaining high case hardness with high core strength and toughness. Its high alloy content makes it suitable for components with relatively heavy sections. The combination of high alloy content and low carbon makes it possible to achieve a high core hardness with a narrow hardness range between heavier and thinner sections.
It is an alloy that offers strength with excellent toughness and ductility, and it may be used to advantage without carburizing. Carburized, a highly wear resistant case is produced which is useful in extremely difficult applications.
The AIRCRAFT QUALITY grade is produced following the best electric furnace steel making practices. It is vacuum degassed to insure meeting the magnetic particle standards of AMS 2301.
This grade is also available as a Premium Aircraft Quality product using the consumable electrode vacuum remelting process. 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.
N/AIntended primarily for critical carburized parts requiring high minimum core hardness with a relatively narrow hardness range. Also where rigid magnetic particle inspection standards are utilized in final inspection.
Premium Aircraft Quality is used where even more stringent cleanliness is required, as well as for highly stressed parts requiring greater transverse ductility and toughness.
Hardening
N/AEnd-quench hardenability values are Rockwell "C" 43 maximum at 1/16" and Rockwell "C" 31 minimum at 6/16"
Heat Treating
N/ANormalize—1700°F
Carbiirize—1700 °F
Austenitize—1500°F
Quench—Oil
Temper—300 °F for maximum strength and hardness
450 °F for maximum core toughness
