Experimental Assessment of Cutting Parameters in Ultrasonic-Assisted Milling of Al2O3 Ceramics for Narrow Channel Fabrication

The machining of technical ceramics remains challenging due to the need to achieve high dimensional accuracy, good surface quality, and acceptable tool life when processing hard and brittle materials. This study investigates the influence of cutting parameters on the machining time, dimensional accuracy, surface roughness, and tool wear during ultrasonic-assisted milling of aluminum oxide (Al2O3) ceramics. A planned experiment comprising nine experimental trials is performed using a DMG Ultrasonic Linear 20 machine and a specialized diamond cutting tool with a diameter of 1.2 mm. The investigated parameters included cutting speed, feed rate, and depth of cut, varied within the ranges of 65–85 m/min, 30–50 mm/min, and 0.03–0.05 mm, respectively. A narrow channel with nominal dimensions of 1.5 mm in width, 11.5 mm in length, and 1.5 mm in depth is machined in each specimen. Dimensional measurements, surface roughness evaluation, and tool wear monitoring are performed to assess process performance. All nine specimens met the specified dimensional tolerances. The measured arithmetic mean surface roughness (Ra) ranged from 0.183 to 0.298 µm, while tool length wear remained between 0.001 and 0.003 mm. The shortest machining time is 16 min and 15 s, achieved with a cutting speed of 85 m/min, a feed rate of 50 mm/min, and a depth of cut of 0.05 mm. Compared with the initial machining conditions, this combination reduced machining time by approximately 62% while maintaining dimensional compliance and a low surface roughness. The results provide a comparative experimental reference for the investigated machining configuration, although the absence of replicate trials limits the assessment of process variability and repeatability.