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In this study, the effect of temperatures and cooling rates of heat treatment on the microstructure of a powder metallurgy (PM) Ti-46Al-2Cr-2Nb-(B,W) (at.%) alloy was studied. Depending on the cooling rate and temperature, the different structures were obtained from the initial near-γ (NG) microstructures by heat treatment in the α+γ field. The results show that the microstructures of samples after furnace cooling (FC) consist primarily of equiaxed γ and α 2 grains, with a few grains containing lamellae. Duplex microstructures consist mainly of γ grains and lamellar colonies were obtained in the quenching into another furnace at 900°C (QFC) samples. However, further in- creasing of the cooling rate to air cooling (AC) induces the transformation of α→α_2 and results in a microstructure with equiaxed γ and α_2 grains, and no lamellar colonies are found.
In this study, the effect of temperatures and cooling rates of heat treatment on the microstructure of a powder metallurgy (PM) Ti-46Al-2Cr-2Nb- (B, W) (at.%) Alloy was studied. rate and temperature, the different structures were obtained from the initial near-γ (NG) microstructures by heat treatment in α + γ field. The results show that the microstructures of samples after furnace cooling (FC) Duplex microstructures consisting mainly of γ grains and lamellar colonies were obtained in the quenching into another furnace at 900 ° C (QFC) samples. However, further in- creasing of the cooling rate to air cooling (AC) induces the transformation of α → α_2 and results in a microstructure with equiaxed γ and α_2 grains, and no lamellar colonies are found.