• These are "triple alloy" carburizing steels. The nickel imparts good toughness and ductility, and the chromium and molybdenum contribute increased hardness penetration and wear. They are readily carburized, and the well-balanced alloy content permits hardening to produce a strong, tough core and high case hardness. They have excellent machinability and respond well to polishing operations. Because of the fine combination of properties that may be developed, as well as the ease with whichmore