Edge finishing and deburring of back surfaces of microholes using micro-cutting tools

► The edge finishing and deburring of the back surfaces of micro-through holes from the front surfaces are carried out. ► Micro-cutting tools are fabricated by EDM and used for processing holes. ► Helical tool feeding is employed and workpieces are ultrasonically oscillated. ► A hole drilled using a 0.15-mm-diameter drill in a 0.2-mm-thick plate is successfully deburred and edge-finished.