Enhancing Mechanical Properties of TiZrAlV by Engineering a Multi-Modal-Laminated Structure

In the present study, microstructure and mechanical properties of a new beta-metastable TiZrAlV prepared via thermomechanical processing (TMP) treatments have been studied. An excellent combination of ultimate tensile strength (sigma(b) approximate to 1 630 MPa) and ductility (epsilon(f) approximate to 6.6%) has been achieved in the alloy after cold rolling, thermal annealing (665 degrees C/1 h), and two-step aging (650 degrees C/0.5 h + 450 degrees C/2 h). This is attributed to the formation of a refined beta microstructure with grain size of approximate to 10 mu m and a multi-modal-laminated structure that consists of large primary alpha(p) grains (2 mu m, 9.5 vol %) and coarse alpha precipitates (300 nm, 21 vol%) and fine alpha platelets (50 nm, 65 vol%). The fine alpha platelets contribute to high strength while the large primary alpha(p) grains and the refined b grain size provide ductility.