Milling Vibration Suppression Mechanism and Stability Analysis by Introducing the Spiral Acoustic Black Hole as a Vibration Absorber in Milling Thin-Walled Parts

Harmful vibrations during milling can negatively impact the quality and efficiency of the machined surface. The current active and passive vibration control methods have problems with complex regulation, hysteresis, and narrow frequency bands; hence, the need for a simple and efficient damper with a wide range of regulation frequencies. To reduce the milling vibrations efficiently, this paper originally introduces the spiral acoustic black hole (ABH) as a vibration absorber in milling thin-walled parts and explores its mechanism of absorbing milling vibration. The absorbing mechanism of ABH structure when undergoing the milling vibration was studied using the FEA method first. Afterwards, the dynamic modeling and modal testing of the milling system were performed to investigate the effect of the spiral ABH structure on the modal parameters and the milling stability for the thin-walled part. The milling experiments of a typical thin-walled structural part were performed to evaluate the effectiveness of the spiral ABH structure in suppressing the milling vibration. The results showed that the addition of spiral ABH can enhance the stability domain, increase the critical depth of cut by 7.849 mm, suppress vibration during milling, reduce vibration amplitude by 66%, and improve the surface quality by 50%. The findings of this paper show that the spiral ABH structure has considerable potential in efficiently suppressing vibrations during the milling of thin-walled parts.