Investigation of ultrasonic deformation characteristics of ultrathin miniaturized TA1 foil

Ultrasonic vibrations (UV) are widely employed in various precision manufacturing processes to obtain high product quality and processing efficiency. However, the plastic deformation behavior of high-strength, low formability and ultrathin (<100 μm) materials during UV-assisted forming is not unveiled yet. Herein, the influence of UV on micro-deformation of ultrathin TA1 foil (20 μm) is investigated through UV-assisted uniaxial tensile tests at room temperature. The macro-mechanical behavior is demonstrated by the stress-strain curve and a numerical model is established by using a fifth-order polynomial to assess stress reduction. Moreover, electron backscatter diffraction (EBSD) analysis and scanning electron microscopy (SEM) are utilized to reveal the UV softening mechanism at the microstructural level. The results demonstrate that the microstructure has been significantly altered during the UV-assisted uniaxial tensile process. The systematic investigation of macro- and micro-mechanical behavior provides an enhanced understanding of the UV-assisted micro forming process.