The effect of austenitizing temperature on the as-quenched hardness of three martensitic grades is shown in the graph. Specimens were wrought martensitic stainless steels containing 0.15% max carbon. The hardness increases with increasing austenitizing temperature to about 1800°F, then decreases because of austenite retention and (occasionally) the formation of δ-ferrite.
Certain anomalies in these steels that should be considered before specifying a heat-treating procedure are exemplified in the opposing injurious effects of the high and low extremes of austenitizing temperature, depending on the subsequent tempering temperature.
Volume 4D, Heat Treating of Irons and Steels ⇒ Heat Treated High-Alloy Steels ⇒ Heat Treating of Martensitic Stainless Steels ⇒ Hardening
