1.3343 M2 Skh51 Hot Rolled Forged Qt Steel Round Bar

1: M2 steel introduction
    AISI M2 Tool Steel is molybdenum based high-speed steel in tungsten-molybdenum series. HSS grade steel M2 is a medium alloyed high speed steel which has good machinability. The H-SS M2 chemical composition gives a good combination of well-balanced toughness, wear resistance and red hardness properties. Widely used for cutting tools such as twist drills, taps, milling cutters, saws, knives etc. Also commonly used in cold work punches and dies and cutting applications involving high speed and light cuts.

    Grade M2 High Speed Steel is by far the most popular high speed steel replacing high speed steel grade T1 in most applications because of its superior properties and relative economy. 

    The mechanical properties mainly include tensile strength, yield strength, elongation, area or reduction, hardness, impact value, non-metalic inclusion etc. Different heat treatment, the mechanical properties will be different, such as normalized, tempered, QT. If you want to know the properties, kindly contact the salesman.

7. Heat Treatment of M2 Steel HSS

Anneal

    Heat to 1600° F, soak thoroughly at heat. Furnace cool 25° F per hour to 900° F, air cool to room temperature. Approximate annealed hardness 241 Maximum Brinell.

    Stress Relief of Unhardened Material: Heat slowly to 1200 to 1250° F. Soak for two hours per inch of thickness at heat. Slow cool (furnace cool if possible) to room temperature.

Harden

    Heat slowly to 1550° F, soak thoroughly, heat to 1850° F, soak thoroughly. Soak time in the furnace varies from a few minutes to 15 minutes, depending tool size, heat capacity of the furnace, and the size of the charge. - Heat to 2150 to 2200° F for max. toughness and minimum distortion. - Heat to 2250 to 2275° F for max. hardness and abrasion resistance.

Quench

    For full hardness, oil quench to 150-200° F. Air quench to 150° F. When quenching in hot salt maintain the quench just above the Ms temperature. After equalizing withdraw parts from the hot salt and air cooled to 150° F.

Temper

    Double temper is mandatory, three tempers are sometimes preferred. Soak for 2 hours per inch of thickness. Air cool to room temperature between tempers. The best tempering range for hardness, strength and toughness is 1000 to 1050° F.

8: Delivery condition

    For hot forged  bar, usually the delivery condition is hot forged, annealed/QT, rough turned/Black surface.
    For hot rolled bar, usually the delivery condition is hot rolled, annealed/QT, Black surface.
    For hot forged block, usually the delivery condition is hot forged, annealed/QT, milled surface/Black surface
    For hot rolled plate, usually the delivery condition is hot rolled, annealed/QT, black surface.
    For cold drawn bar, usually the delivery condition is cold drawn, annealed/QT, peeled/black surface