PRECIPITATION HARDENING STEEL WITH IMPROVED TOUGHNESS AND METHOD

摘要

In some aspects, a heat treatment process is described for precipitation hardening steel. The heat treatment process can include a solution treatment for a precipitation hardening steel part. The solution treatment includes heating the precipitation hardening steel part to an austenitizing temperature. The heat treatment process can also include a quenching or cooling treatment, in which the precipitation hardening steel part is cooled to a martensitizing temperature. The heat treatment process can also include an aging treatment, in which the precipitation hardening steel part is heated to a temperature of 1000° F. and held at that temperature for five or more hours until a fracture toughness of the precipitation hardening steel part is greater than 120 ksi√in.

主权项

1. A heat treatment process for precipitation hardening steel comprising:
a solution treatment for a precipitation hardening steel part, wherein the precipitation hardening steel part is heated in a furnace to an austenitizing temperature; a cooling treatment for a precipitation hardening steel part, wherein the precipitation hardening steel part is cooled to a martensitizing temperature of at least −100° F.; and an aging treatment for a precipitation hardening steel part, including heating the precipitation hardening steel part in a furnace at a temperature of at least 950° F. for at least 6 hours until a fracture toughness of the precipitation hardening steel part is greater than 120 ksi√in and until a yield strength is greater than 175 ksi.