A high-performance longitudinal-bending ultrasonic vibration horn: structural innovation and dynamic testing

Area of Science:

• Mechanical Engineering
• Materials Science
• Vibration Analysis

Background:

• Traditional cutting tools for rotary machining require axisymmetric designs for dynamic balance.
• Existing longitudinal-bending composite ultrasonic vibration horns are non-axisymmetric, hindering their use in rotary ultrasonic vibration-assisted grinding (RUVAG) systems due to mass eccentricity.
• Non-axisymmetric structures in rotary motion often rely on ingenious designs for dynamic balancing.

Purpose of the Study:

• To propose and validate a novel non-axisymmetric horn design for longitudinal-bending composite ultrasonic vibration that achieves dynamic balance during rotation.
• To integrate dynamic balancing and wave theories for mathematical modeling and finite element analysis optimization of the horn structure.
• To experimentally investigate the vibration performance, resonant frequencies, and amplitude characteristics of the proposed cam-profile horn.

Main Methods:

• Mathematical modeling integrating dynamic balancing theory and wave theory.
• Finite element analysis for horn structure optimization.
• Design and manufacturing of two cam-profile horns with distinct geometric dimensions.
• Experimental validation of resonant frequencies and vibration amplitudes (longitudinal and bending).

Main Results:

• Experimental resonant frequencies showed low relative errors (0.478% and 0.728%) compared to simulations.
• Measured longitudinal and bending vibration amplitudes were validated against simulated results with relative errors ranging from 7.15% to 13.77%.
• Cam dimensions significantly influence vibration amplitudes, with increased cam ratio enhancing vibration; ultrasonic generator power also amplifies vibration modes.

Conclusions:

• The proposed cam-profile horn successfully achieves longitudinal-bending composite vibration in a non-axisymmetric structure while maintaining dynamic balance for rotary applications.
• The cam-profile horn design demonstrates superior vibration performance and precise amplitude controllability, making it suitable for RUVAG systems.
• Experimental results confirm the theoretical predictions and highlight the influence of cam geometry and power on vibration characteristics.