Effect of austenite grain size and thermal history on low-temperature intergranular fracture of Ni-Cr-Mo-V rotor steel

Abstract

Two 3.5Ni-Cr-Mo-V steels have been studied in an attempt to gain insight into isothermal embrittlement of low-pressure rotors during service. An investigation was made to determine the influence which austenite grain size and type of acicular microstructure exert on temper embrittlement; particular attention was given to the thermal history of the steel, which may be a significant factor.