Numerical and experimental study on ultrasonic vibration-assisted micro-channelling of glasses using an abrasive slurry jet

The ultrasonic-vibration assisted micro-channelling process on glasses by an abrasive slurry jet (ASJ) is presented and discussed both numerically and experimentally. A numerical investigation using the dynamic meshing technique in Computational Fluid Dynamics (CFD) is carried out first to model the ASJ flow and explore the effect of ultrasonic vibration on the stagnation zone, particle impact velocity and impact angle, and viscous flow induced erosion process. It has been found that the static pressure in the stagnation zone, particle impact velocity and impact angle are varied periodically with an assistance of the ultrasonic vibration on the workpiece which in turn could affect the material removal process in ASJ micro-channelling of glasses. It is also found from simulation that the ultrasonic vibration is beneficial to the viscous flow induced erosion during the low pressure ASJ micro-machining process. Then, a set of ultrasonic vibration-assisted micro-channelling experiments are conducted on glasses using an ASJ to evaluate its effect on the major micro-channelling performance. It is found that ultrasonic vibration-assisted ASJ micro-channelling increases the material removal rate, channel depth and top channel width, while decreases the channel wall inclination angle, as compared to the traditional ASJ micro-channelling process at the same experimental condition. However, the surface quality on the bottom of the channel seems to be not significantly affected by the ultrasonic vibration. These findings from the experiment are in a reasonably good agreement with the corresponding simulated results.