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A novel electromagnetic shocking treatment (EST) has been put forward to optimize interface microstructure and further enhance the mechanical properties of titanium alloys. In details, tensile properties and impact toughness of TC11 titanium alloy have been investigated with room temperature tensile test and Charpy impact testing. Then, tensile fracture and impact fracture as well as microstructure including phase and interface are characterized and analyzed. The results show that after EST, the tensile strength increase slightly, the elongation decreases while the impact energy is enhanced obviously. Besides, with the maximum temperature rising on alloy sample surface being limited to just 210 °C, EST promotes the phase transformation from β to α instantly, also, wrinkling at interface is more commonly observed in EST sample, which indicates that nonlinear interface wetting and bridging are promoted by EST. It demonstrates that the increase of α mainly accounts for the slight improvement of tensile strength and the decrease of elongation. Also, considering that the phase transformation from β to α is unfavorable to the improvement of impact toughness, the degree of interface wetting and bridging which is dependent on the electromagnetic shocking energy plays a decisive role for the enhancement of impact energy of EST sample. This work provides a novel EST method to selectively embellish interface and further to improve the properties and performance of solid alloys related with interface microstructure. • EST enhances impact toughness of TC11 titanium alloy by embellishing interface. • EST induces nonlinear interface wetting and further promotes interface bridging. • EST promotes β.→α solid phase transformation instantly by interface wetting. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel electroshock treatment (EST) has been proposed to improve fatigue life of titanium alloy. • After appropriate EST, the transformed β phase was broken and more finely dispersed acicular secondary α phase was formed. • Appropriate EST led to dissolution of unstable phase AlTiHx and generation of nanoscale strengthening phase Al 24 Ti 8 at relatively low temperature. To improve the service life of titanium alloys, a novel electroshock treatment (EST) with low frequency, alternating pulse, and limited energy density is proposed in this study. The effects of different parameters process on the fatigue life of TC11 alloy were investigated. Experimental data show that low-cycle fatigue life of the alloys increased 22.5% by the appropriate EST. The mechanism affecting the fatigue life was studied by SEM and TEM. The results show that after the appropriate EST, the volume fraction of the α phase increased, the lath-like transformed β phase was broken and dissolved locally, accompanied by the formation of a secondary α phase and its morphological transformation from flake-like to more finely dispersed acicular. It was found that the appropriate EST led to the nanoscale solid-state phase transition; namely, the dissolution of an unstable brittle AlTiH x phase in the alloy matrix and precipitation of the Al 24 Ti 8 strengthening phase with a size close to 5 nm in the β phase. These transitions occurred when the local maximum temperature of the sample recorded was only 296.8 °C. In summary, the microstructural evolution and nanoscale phase transformation of titanium alloy by the EST process significantly increased the fatigue life. [ABSTRACT FROM AUTHOR]