Enhancing Precision and Quality in Micro-blanking of Annular Foil Parts through Ultrasonic Vibration Assistance

This study investigates the application of ultrasonic vibration-assisted micro-blanking technology to improve the forming quality and dimensional accuracy of precision annular foil parts. Using T2 copper foil with a thickness of 80 μm, experiments were conducted with and without ultrasonic vibration. Key performance metrics such as concentricity, dimensional accuracy, and flatness were evaluated by video measuring instrument and laser confocal microscope. The cross section topography and surface roughness were also characterized by scanning electron microscope (SEM) and atomic force microscope (AFM). The results demonstrated that ultrasonic vibration significantly enhanced forming precision, with concentricity deviations within Φ0.010 mm and dimensional errors reduced to ± 0.01 mm. Flatness improvements of up to 51.8% were achieved, attributed to residual stress relief and enhanced deformation uniformity. Cross section analysis revealed that ultrasonic vibration reduced edge radius and increased the bright zone proportion; section quality is optimal when the grain size is 21.0 μm. Surface roughness in the bright zone was notably reduced by 66.7% due to the polishing effect of ultrasonic vibration. These findings highlight the effectiveness of ultrasonic vibration in mitigating size effects and improving the overall quality of micro-blanked parts, offering valuable insights for advancing precision micro-forming processes.