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Edge-chipping, surface roughness and dimensional accuracy are crucial quality aspects of drilled holes in hard-to-cut material such as glass, ceramics and carbon fiber reinforced plastics. In this article, an experimental study was conducted to investigate the quality measures of holes produced by rotary ultrasonic drilling (RUD) and conventional drilling. Edge-chipping width at tool exit side, the surface roughness (Ra and Rz), out-of-roundness, cylindricity error and hole conicity were the main responses when drilling soda glass using diamond abrasive tools and a cutting fluid. Statistically designed experiments were carried out for rotary ultrasonic and conventional drilling (CD) at two levels of tool feed rate (0.6 and 6 mm/min), spindle speed (3,000 and 8,000 rpm) and tool particles-concentration. Analysis of variance was used to define the significant factors and their interactions and build models for predicting the responses. The results showed that reducing the chipping, surface roughness and roundness error. The normal tool concentration showed a substantial effect in improving the surface quality and reducing the hole-geometrical errors. [ABSTRACT FROM AUTHOR]

Soda glass is a difficult-to-machine material widely used in industry. In this work, ultrasonic-assisted milling (UAM) of soda glass is investigated and compared to conventional milling (CM). Statistically designed experiments are conducted with and without cutting fluid at different levels of the spindle speed, feedrate, depth of cut, and tool particle-concentration. The significant factors and their interactions are identified by modelling the process parameters and the corresponding responses in terms of cutting forces and moment. Results show a reduction of axial cutting force and moment at higher spindle speed and lower feedrate and depth of cut. The application of ultrasonic vibration-assistance and cutting fluid demonstrates a significant effect on the axial cutting force and moment. [ABSTRACT FROM AUTHOR]