Development of a two-frequency, elliptical-vibration texturing device for surface texturing

This study presents the design of a Two-frequency, elliptical-vibration texturing (TFEVT) device. The device was designed to be used in a surface texturing process, and its functionality is based on a combination of ultrasonic (> 20 kHz) and low vibration frequencies (> 100 Hz). The device consists of two parts: The Ultrasonic elliptical motion transducer (UEMT) and the Low frequency displacement amplifier (LFDA). A modal analysis simulation and dynamic experiments were conducted to investigate the dynamic characteristics of the device. The modal simulation was carried out using finite element analysis and the dynamic experiment was evaluated using Frequency response function (FRF) analysis. The working principle of the UEMT is based on a resonance transducer, and the angle between the two Langevin transducers was set as 90°. The UEMT has two vibration modes, symmetric and asymmetric, and according to experimental data, its working frequency is 24 kHz at the 6^th resonance vibration mode when a Polycrystalline diamond (PCD) tool is attached. The UEMT is able to generate an elliptical locus that has a vertical amplitude of 1.4 μm and a horizontal amplitude of 0.6 μm, under a phase-shift of 90°. The design of the LFDA is based on a double parallel four-bar flexure hinge, and the displacement output ratio is set to 5. The working principle of the LFDA is based on a non-resonance transducer. The working frequency of the LFDA is below its first of natural frequencies (≈1060 Hz), and it is able to generate sinusoidal motion with a maximum peak-to-peak amplitude of 9 μm. Finally, to investigate the feasibility of the TFEVT device for use in a surface texturing process, several micro-groove cutting tests were performed on an AISI 1045 alloy steel.