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 tempera...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 increasing 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.展开更多
基金supported by the National Natural Science Foundation of China (No. 51101003)
文摘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 increasing 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.
