Performance of Monopole Concentrator during Microwave Drilling of Perspex

The applications of microwaves in engineering has been fast expanding, one such area is micromachining and micro-fabrication. A series of experiment with different types of concentrator (steel, copper and nichrome) wascarried out. Different machining conditions like variable power, location and movement were considered. The drilled hole shows development of three differentheat affected zones (HAZs). The performance of the process was evaluated in term of the residue diameter, HAZ diameter and the hole diameter. Energy Dispersive Spectroscopy (EDS) and field emission scanning electron microscope (FESEM) were used to assess the zone and damage of the monopole concentrator used as drilling tool. The drill bit damage in its length was controlled with careful selection of process parameters. An optimum processing condition was determined experimentally, for minimum residue generation, minimum HAZ and minimum oversize of drilled holes. The depth of through hole in perspex material was maintained constant at 2 mm.

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