Theories and experiments on effects of acoustic energy field in micro-square cup drawing

A vibration-assisted uniaxial tension experimental setup was designed to study the stress-strain relationship induced by ultrasonic excitation, and an acoustic-plastic constitutive model was developed and calibrated based on dislocation density evolution under experimental data. Also a prediction model for the drawing height of micro-square cups in vibration-assisted plastic deformation was investigated based on the dangerous section stress theory and the acoustic-plastic constitutive model. The prediction model was validated by designing a finite element model and an experimental deep drawing system under various working conditions, in which 200-mu m-thick stainless steel 304 was excited by ultrasonic vibration at frequency 19.891 kHz and different amplitudes. It was found the predicted drawing height of micro-square cups agreed well with the experimental results, indicating the prediction model was able to accurately predict the drawing height of micro-square cups during vibration-assisted metal micro-forming.