Formation of ductile ultrafine eutectic structure in Ti–Fe–Sn alloy

Abstract: A Ti67.79Fe28.36Sn3.85 (at.%) alloy has been prepared through arc-melting and solidification at a cooling rate of 40–10K/s. The as-prepared microstructure exhibits a two-phase ultrafine eutectic consisting of FeTi (B2) and β-Ti (A2) phases. The mechanical properties (maximum strength, σ max =1939MPa; strain to fracture, ɛ f =13.5%) are considerably improved if compared with the model Ti70.5Fe29.5 eutectic alloy (σ max =1733MPa, ɛ f =3.4%). The improvement of plastic deformability is assessed in terms of a detailed investigation of the microstructure and fractographic studies. The presence of Sn is believed to boost the ease of slip transfer across the interface between the A2/B2 phases due a higher lattice mismatch between the structures. [Copyright &y& Elsevier]