Ultrasonic Vibration-Assisted Intrinsic Modeling and Tissue Evolution of 7075 Aluminum Alloy

Ultrasonic-assisted machining technology has been widely used in engineering practice. Tensile tests were carried out on 7075 aluminum alloy under ultrasonic vibration conditions. The results show that with the application of ultrasonic vibration, there is an obvious ultrasonic softening effect, and the flow stress during the deformation of the aluminum alloy is reduced, and the maximum percentage of yield strength and tensile strength are reduced by 9.69% and 8.9%, respectively. The elongation increases and then decreases and reaches a maximum value of 21.39% at an amplitude of 8 μm. In addition, by improving the Z–A constitutive model, the constitutive relationship model of aluminum alloy under ultrasonic vibration-assisted conditions was established, and the predicted values were compared with the experimental values. The results show that the constitutive model can accurately predict the stress–strain relationship of aluminum alloy under different amplitudes, which provides a theoretical basis for the application of ultrasonic vibration-assisted forming technology in aluminum alloy materials.