Microstructure and Mechanical Properties of a High-Strength Ti-4Al-2Fe-3Cu Alloy Fabricated by Sintering and Hot Extrusion

A Ti-4Al-2Fe-3Cu (wt pct) alloy containing only low-cost alloying elements was fabricated by vacuum sintering a blend of TiH2, Al, Fe, and Cu powders at 1200 °C for 1 hour followed hot extrusion the same temperature. The as-extruded exhibited microstructure consisting mainly α/β lamellar colonies Ti2Cu as minor phase. average colony size lamella thickness were 118 12 µm, respectively, Fe predominantly distributed in β lamellae. had high tensile yield strength (YS) ultimate (UTS) 1248 1270 MPa, but limited ductility (elongation to fracture: 2.3 pct). Annealing 750 4 caused increase 145 17 volume fraction phase decreased with annealing. These microstructural changes resulted slight decrease YS UTS 1221 1253 clear elongation fracture reaching pct. This work demonstrates that combination relatively low-temperature sintering, extrusion, annealing can be effectively utilized fabricate appreciable ductility.