AISI 8620 Steel is a low alloy nickel, chromium, molybdenum case hardening steel, generally supplied in the as rolled condition with a maximum hardness HB 255max. SAE steel 8620 offers high external strength and good internal strength, making it highly wear resistant. AISI 8620 steel has a higher core strength than grades 8615 and 8617.SAE 8620 alloy steel is flexible during hardening treatments, thus enabling improvement of case/core properties. Pre hardened and tempered (uncarburized) 8620 can be further surface hardened by nitriding but will not respond satisfactorily to flame or induction hardening due to its low carbon content.

    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.

6. ASTM 8620 Steel Heat Treatment
Annealing
    AISI 8620 steel may be given a full anneal by heat to 820℃ – 850℃, and hold until temperature is uniform throughout the section and cool in furnace or air cooled.
Tempering
    Tempering of heat treated and water quenched parts of 8620 steels (not carburized) is done at 400 F to 1300 F to improve case toughness with minimal effect on its hardness. This will also reduce the possibility of grinding cracks.
Hardening
    The AISI steel 8620 will be austenitized at around 840°C – 870°C, and oil or water quenched depending upon section size and intricacy. Cool in Air or Oil required.
Normalizing
    1675oF (910oC) and air cool. This is another method of improving machinability in 8620 material; normalizing might also be used prior to case hardening.

7: Delivery condition

    For hot rolled bar, usually the delivery condition is hot rolled, annealed/QT, Black surface.