Abstract

This study investigates surface formation characteristics in elliptical ultrasonic assisted grinding (EUAG) of monocrystal sapphire. During EUAG process, the workpiece is imposed to ultrasonically vibrate in two directions, i.e., vertical and parallel to work-surface, by using an elliptical ultrasonic vibrator. In our previous work, the vibrator has been produced by bonding a piezoelectric ceramic device (PZT) on a metal elastic body. When two alternating current voltages with a phase difference are applied to the PZT at the same frequency that is close to the resonant frequency of the longitudinal and bending mode of the vibrator, two dimensional ultrasonic vibrations are generated simultaneously, resulting in an elliptical motion on the end face of the vibrator. In this paper, to clarify the work-surface formation characteristics in EUAG of sapphire material, grinding experiments are carried out involving sapphire substrate. In experiments, work-surface roughness is measured, and the ground work-surface morphology is examined by scanning electron microscope (SEM). The experimental results are summarized as: (1) Compared with conventional grinding (CG), the elliptical vibration leads to a decrease of surface roughness up to 25% in EUAG; (2) The surface roughness has a monotonously increasing trend with the increasing wheel depth of cut in both EUAG and CG, but has little variation with the worktable feed rate. As the wheel speed increases, the surface roughness decreases until it reaches a minimum, and then increases in a monotonous trend in both EUAG and CG; (3) The surface quality in EUAG has a significant improvement, and it is prone to achieve the ductile regime grinding of sapphire compared with CG. These indicate that the elliptical ultrasonic assisted grinding is an efficient technique for high performance machining of monocrystal sapphire.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.