Ultrasonic vibration assisted micro-bending of TA1 titanium sheets

Ultrasonic vibration (UV) assisted micro-bending experiments were conducted on TA1 titanium alloy sheets to study its effectiveness in controlling springback under size-reduced conditions. The influences of ultrasonic amplitude and holding time on bending force and springback behavior were systematically evaluated. Results show that UV significantly reduces bending force and springback angle, with the reduction becoming more pronounced as sheet thickness decreases, indicating an effective suppression of springback size effect. UV does not alter grain morphology but substantially homogenizes microscale deformation by reducing strain localization. This enhanced deformation compatibility increases the proportion of irreversible plastic deformation and weakens elastic recovery during unloading. The underlying mechanism of springback suppression is therefore attributed to ultrasonic-induced dislocation activation and stress relaxation, which are more effective at higher ultrasonic energy density in thinner sheets. The proposed process provides an effective approach for improving dimensional accuracy and process reliability in micro-scale forming of titanium sheets.