Microstructure and hardness evolution in MAR-M247 Ni-based superalloy processed by controlled cooling and double heat treatment

► Physical simulation of casting of MAR-M247 Ni-based superalloy is performed. ► Effect of cooling rate and double heat treatment on the microstructure and hardness is studied. ► Grain size is determined by cooling rate, no grain growth occurs during double heat treatment. ► Carbide size, volume fraction and spacing depend on both cooling rate and double heat treatment. ► Hardness is related to the carbide size and carbides volume fraction.