Tailoring strong basal texture and enhanced strength in a β-solidifying TNM alloy via two-step hot extrusion

A two-step hot extrusion process above the α-transus temperature was developed to tailor the lamellar microstructure of a TNM alloy. This method effectively suppresses abnormal grain growth by controlling deformation-induced heating while accumulating sufficient strain. The resulting material exhibits a refined and uniformly oriented lamellar structure, with strong basal texture in the α phase intensified through increasing extrusion ratio. The tensile strength reached ∼1113 MPa without loss of ductility, attributed to a combination of grain and microstructural refinements and a higher fraction of lamellae aligned parallel to the extrusion direction, which enhances interfacial strengthening by impeding dislocation motion. This work demonstrates that multi-pass extrusion is a viable route to achieve high-performance TiAl alloys through texture control without microstructural coarsening.