Experimental Study of Microgroove Surface Using Three-Dimensional Elliptical Vibration Texturing

This paper presents our preliminary study of the microstructured surface on microgrooves patterns, which have manufactured using the three-dimensional elliptical vibration texturing (3D-EVT) method. The 3D-EVT method uses a three-dimensional trajectory of elliptical locus of the cutting tool tip in high vibration frequency to fabricate the microstructure or the vibration mark pattern on the machined surface. The experimental study has been done with a variation of the nominal cutting speeds from 300 to 600 mm/min. The preliminary results showed that in the low nominal cutting speed of 300 and 450 mm/min, the microstructured surfaces were not manufactured well due to the bulging existence on the microstructured surface in which it is correlated with the build-up edge phenomena. On the other hand, a relative excellent microstructured surface can be achieved at the higher nominal cutting speed of 600 mm/min. In addition, a lubricant could be used to obtain an excellent microstructured surface to avoid the built-up edge phenomena.

Design of a High Bandwidth Nonresonant Tertiary Motion Generator for Elliptical Vibration Texturing

This paper presents the design and characteristics of a new two-dimensional nonresonant tertiary motion generator which is based on the flextensional structure. A tool holder connects two perpendicularly placed flextensional actuators with flexure hinges which decouple the motion outputs from the two actuators. Piezoelectric stacks, which are preloaded through precision screws, are used to provide input displacements. By balancing the requirements of driving current, stiffness, and the displacement amplification ratio, the proposed design is targeted to operate at above 10 kHz with two-dimensional vibrations amplitude of 10 μm in each direction. Technical difficulties in driving a nonresonant mode piezoelectric actuator at a high frequency are discussed. The solutions and optimization procedures are presented in this paper. The design is optimized by finite-element simulation; and the results are presented and verified by our prototype design.