【摘 要】
：
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
【机 构】
：
School of Materials Science and Engineering, Beijing University of Aeronautics and Astronautics, Bei
论文部分内容阅读
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 face cooling (FC) consist primarily of equiaxed γ and α2 grains,with a few grains containing lamellae.Duplex microstructures consist mainly of γ grains and lamellar colonies were obtained in the quenching into another face at 900℃ (QFC) samples.However,further increasing of the cooling rate to air cooling (AC) induces the transformation of α→α2 and results in a microstructure with equiaxed γ and α2 grains,and no lamellar colonies are found.
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