Effect of heat treatment on prior grain size and mechanical property of a maraging stainless steel

Abstract

Effect of the heat treatment, including solution treatment (ST) and aging treatment (AT), on the prior austenite grain (PAG) size, microstructure and mechanical properties of a precipitation hardening maraging stainless steel was investigated. The results indicate that the relations between PAG size and yield strength (sigma(y)) under both ST and AT conditions obey the Hall-Petch relationship. Furthermore, after ST at 1050 degrees C for 1 h+cryogenic treated (CT) at -70 degrees C for 8 h+AT at 535 degrees C for 4 h, the tested steel showed its ultimate tensile strength (sigma(b)) and sigma(y) over 1900 MPa and 1750 MPa, respectively.