Hot deformation and softening response in boron-modified two-phase titanium aluminide Ti-48Al-2V-0.2B

Hot deformation and softening response for the titanium aluminide Ti-48Al-2V-0.2B has been investigated. The deformation response to softening mechanisms has been examined. Deformation experiments were carried out in the strain rate range 0.01-10 s(-1) keeping the temperature constant at 1200 degrees C and in the temperature range 1000-1200 degrees C at the strain rate 1 s(-1). With an increase in strain rate, the microstructural changes associated with the softening mechanism include breaking of the lamellae, spheroidization of the broken laths and dynamic recrystallization. For the strain rate 1 s(-1), deformation in the (alpha(2) +gamma) phase field leads to fine recrystallized grains, remnant lamellae and cavitation along the grain boundaries (for temperatures 1000 and 1100 degrees C). Deformation in the (alpha +gamma) phase field leads to dynamic recrystallization at the shear bands, within the lamellae, breaking and rotation of the alpha phase during the continuous increase in the deformation strain.

Automated summary

Hot deformation and softening response of titanium aluminide Ti-48Al-2V-0.2B were investigated, with microstructural changes observed at different strain rates and temperatures. Deformation in different phase fields led to various mechanisms, such as dynamic recrystallization and cavitation along grain boundaries at certain temperatures. These findings provide insights into the softening behavior of the alloy under different deformation conditions.