Drilling into Hard Non-Conductive Materials by Localized Microwave Radiation

The paper describes a novel method of drilling into hard non-conductive materials by localized microwave energy (US patent 6,114,676). The Microwave Drill implementation may utilize a conventional 2.45GHz magnetron, to form a portable and relatively simple drilling tool. The drilling head consists of a coaxial guide and a near-field concentrator. The latter focuses the microwave radiation into a small volume under the drilled material surface. The concentrator itself penetrates into the hot spot created in a fast thermal runaway process. The microwave drill has been tested on concrete, silicon, ceramics (in both slab and coating forms), rocks, glass, plastic, and wood. The paper describes the method and its experimental implementations, and presents a theoretical model for the microwave drill operation. The applicability of the method for industrial processes is discussed.