The pure α-Ti samples were heated at an extremely high rate （～10^6 K/s） to the temperature of β phase zone followed by a rapidly quenching in an electro-pulsing treatment. After the treatment, micrometer-thick lamellar substructures were generated within the original equiaxed α-Ti coarse grains. Misorientations across adjacent lamellae are of a few degrees. The ultrafine lamellar substructures originated from a non-equilibrium α-β-α’ phase transformation during rapidly heating-quenching process with a short exposure time at high temperatures. Tensile strength was increased by about 100 MPa due to the formation of the ultrafine lamellar substructure while the same tensile plasticity （elongation-to-failure） was maintained relative to the original sample. The strengthening effect could be attributed to the effective blockage of dislocation motions by a high density of sub-boundaries.
Weisong ZHAO Wei ZHANG Jinyu GUO Boquan WANG Jingdong GUO Ke LU
