Extraordinary tensile properties of titanium alloy with heterogeneous phase-distribution based on hetero-deformation induced hardening

Abstract

A heterogeneous (α + β) titanium alloy with extraordinary tensile properties was prepared. The heterogeneous microstructures, consisting of soft βfiber and hard (α + β)matrix, were achieved by controlling the distribution of β-stabilizing element. The heterogeneous alloy exhibits ultra-high strength of 1634 MPa with reasonable ductility, which is much higher compared to the homogeneous counterpart. The plastic incompatibility of the βfiber and (α + β)matrix produces hetero-deformation induced (HDI) hardening, which is the main reason for the enhanced strength. Moreover, the α-twining and martensitic transformation are responsible for the good ductility. This work provides a new strategy to achieve superior strength-ductility combination for multi-phase alloys.