Numerical and Experimental Investigation of Deformation Characteristics During High-Frequency Radial Forging of AA7075

Deformation characteristics during high-frequency (1200 strokes /min) radial forging of AA7075-O bar and tube at room temperature were investigated using A GFM SKK-10/R radial forging machine. A comprehensive process model taking account of complex process kinematics, and elastoplastic material behaviour was developed in DEFORM (version 12.1) to investigate the material flow, temperature, and strain evolution during the radial forging process. To verify the simulation results, a novel experimental approach has been used to reveal the material flow behaviour during the radial forging process, in which copper wires were embedded into an AA7075-0 blank prior to the radial forging process and the whole radial forged part was scanned using a Nikon XT H 225 LC X-ray computed tomography system after radial forging. The experimental results provide quantitative characterizations of the material flow in 3D. The experimental and numerical results shed light on the mechanism of fishtail and crack formation during the high-frequency radial forging of AA7075-O and provide guidance to minimise these defects.