Experimental Investigations on Surface Morphology and Critical Voltage Dynamics during SiC Abrasive Aided Ultrasonic-Assisted Rotary µ-ECDM of Glass
摘要
This study presents a novel implementation of ultrasonic-assisted rotary electrochemical discharge machining for precision micromachining of borosilicate glass by integrating ultrasonic tool vibration, workpiece rotation, and silicon carbide abrasive-assisted electrolytes. The influence of varying silicon carbide concentrations (0.5-2.0 wt.%) on key machining parameters hole taper, surface roughness, and heat-affected zone was systematically investigated. Experimental results demonstrate that an optimal abrasive concentration of 1.0 wt.% significantly improves machining outcomes, achieving minimal hole taper (0.032 rad), surface roughness (0.752 µm), and heat-affected zone (0.123 mm2), due to enhanced spark stability, efficient energy distribution, and improved thermal dissipation. Elemental analysis using energy dispersive x-ray spectroscopy confirmed the incorporation of silicon carbide particles on the machined surfaces, while field emission scanning electron microscopy imaging revealed improvements in surface morphology. Discharge behavior was further analyzed through current–voltage time graphs using a digital storage oscilloscope, indicating that 1.0 wt.% silicon carbide also led to the lowest critical voltage (35.51 V) and most stable gas film formation. Comparative analysis with conventional electrochemical discharge machining and ultrasonic-assisted electrochemical discharge machining without abrasives revealed percentage improvements of 80.12% in hole taper, 84.08% in heat-affected zone, and 19.23% in surface roughness. These results validate the technical superiority of the silicon carbide-assisted ultrasonic-assisted rotary electrochemical discharge machining setup in delivering high-precision, thermally efficient micromachining of hard and brittle materials.