عنوان مقاله [English]
In this research, the effect of homogenizing treatment on the microstructure and hardness of polycrystalline GTD 111 Ni-based superalloy was assesed. Homogenizing is one of the key parameters on the efficiency of annealing and ageing of the alloy. The superalloy was melted in a vacuum induction melting furnace and homogenized at 1200 and 1220°C for different times. Microstructure evolution by optical and scanning electron microscopy showed that the segregation of Al and Ti at interdendritic region and W at the core of the dendrite eliminates after homogenizing at 1220°C for 2 hr. volume fraction of carbides, eutectic and gamma prime of the cast alloy was 6%, 10% and 28% respectively that reach to 4%, 7% and 41% after homogenizing at 1220°C for 2 hr. The hardness of the alloy at this condition was 440Hv which is favorable for the homogenized alloy.