Development of β-solidifying γ-TiAl alloys sheet

A β-solidifying γ-TiAl alloys Ti-44.5Al-3.8Nb-1.0Mo-0.3Si-0.1B (at.%) sheet was fabricated by hot pack-rolling, which was carried out directly from the ingot without the hot forging. The microstructure and mechanical properties of as-rolled alloy sheets were investigated. The microstructure of as-rolled alloy sheet shows fine and uniform near gamma microstructure with the size in the range of 5 μm ∼ 15 μm. The excellent hot deformability of the alloy was ascribed to the high volume fraction of disordered bcc β phase formation and the α2/γ lamellar colonies decomposition during rolling in the (α + γ + β) region. The improvement mechanical properties of as-rolled sheet were attributed to grain refinement.