Effect of electropulsing treatment on microstructure and mechanical properties of cold-rolled pure titanium strips

Commercially pure titanium strips were successfully processed by electropulsing treatment (EPT) at relatively low temperature compared to the traditional heat treatment. The results indicated that the ductility of titanium materials is dramatically improved by electropulse while remaining uniaxial tensile strength unchanged, with the increased volume fraction of fine recrystallized grains through electron back-scattered diffraction analysis. However, too high-frequency EPT brought in the coarsened grains and worsened mechanical properties. A mechanism for rapid recrystallization and grain growth in low temperature during EPT was proposed based on the reduction of nucleation thermodynamic barrier and enhancement of atomic diffusion. It is supposed that high-efficiency EPT could provide a highly efficient method for the intermediate-softening annealing of titanium sheet/strips within well-designed process.