Drilling of Ceramics Using Microwave Energy at 2.45 GHz

The current chapter discusses the development in microwave drilling over the years. Microwave drilling is a non-conventional machining process that uses a metallic tool to convert microwave energy into thermal energy, which is then used for the machining of the workpiece. Material is removed from the workpiece during microwave drilling due to the combined action of microwave heating and plasma heating. Microwave drilling has been successfully used for drilling holes in various materials like concrete, glass, ceramics, bones, metals, etc. A 6 mm diameter and 13 mm deep hole in alumina was drilled in 2 min at a microwave input power of 0.9 kW. The smallest hole of 0.5 mm diameter was drilled in borosilicate glass and soda-lime glass; however, defects were present around hole. Use of dielectric in dynamic mode helps in reducing the defects like heat affected zone, overcut; but machining time gets increased slightly.