Alloy 8620 steel is a low-carbon carburizing/case-hardening steel that contains nickel, chromium, and molybdenum as alloying elements. The nickel content provides 8620 with good ductility and toughness while the chromium and molybdenum in its composition increase its hardness penetration and wear.
SAE8620 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.