Quantitative characterization of β-solidifying γ-TiAl alloy with duplex structure

For precise plastic deformation, microstructure control is essential especially for beta-solidifying gamma-TiAl alloy with duplex structure. Based on stereology, the microstructure of isothermally compressed gamma-TiAl alloy was divided into beta(0) grains, remnant alpha(2)/gamma lamellar colonies, alpha(2) and gamma grains. The results show that the volume fraction of beta(0) grains slightly increases in the isothermally compressed gamma-TiAl alloy with the increase of height reduction. Meanwhile, the volume fractions of remnant alpha(2)/gamma lamellar colonies and alpha(2) grains decrease. However, the volume fraction of gamma grains increases from 64.39% to 78.47%. According to the quantitative results, the alpha ->gamma phase transformation was investigated in-depth, and it is found that isothermal compression accelerates the alpha ->gamma phase transformation. The first alpha ->gamma phase transformation is similar to ledge-controlled transformation, through which remnant alpha(2)/gamma lamellar colonies finally convert into gamma grains in isothermal compression. The second is achieved by alpha/gamma phase interface immigration.

Automated summary

The microstructure of isothermally compressed gamma-TiAl alloy was analyzed, revealing an increase in beta(0) grains and a decrease in remnant alpha(2)/gamma lamellar colonies and alpha(2) grains, while the volume fraction of gamma grains increased. The study also found that isothermal compression accelerates the alpha ->gamma phase transformation, with the first transformation resembling ledge-controlled transformation. Additionally, the second transformation is achieved by alpha/gamma phase interface immigration.