The Investigation on Cast Microstructures of NiCoCrAlY Alloy

The casting microstructure of NiCoCrAlY alloy ingot,which is made by vacuum induction melting process,is studied.The result shows that the casting alloy of NiCoCrAlY is mainly composed of four phases,namely γ-phase,γˊ-phase,Y-rich phase and eutectic β+γˊ.Y-rich phase is Ni3.55Co0.5Cr0.2Al0.75Y,surrounding γ phase in the form of mesh.β and γˊare(Ni,Co)Al and(Ni,Co)3Al respectively,and γˊphase is embedded in the β phase as cylindrical rods in the eutectic.