A novel approach for removal of delaminated fibers of a reinforced composites using electrochemical discharge machining

Abstract

Fiber reinforced composites, also referred as fiber reinforced plastics (FRPs) have gained considerable importance in engineering applications due to their unique qualities like high strength and stiffness at lesser weight, chemical inertness, thermal resistance, corrosion resistance, and electrical resistance. Though the machining of FRPs is not recommended, many times it is inevitable and the primary machining process like drilling is essential. This can cause delamination of the fibers thereby adversely affecting the mechanical properties of the composite and requires additional secondary finishing operation. The present investigation explores electrochemical discharge machining (ECDM) as a one of the novel technique to remove the delaminated fibers from such composites. Using ECDM the protruded delaminated fibers from a drilled hole in FRP have been precisely eliminated. Two different approaches viz. top machining and inside machining were followed for this purpose. Process evaluation was done in terms of its ability to remove the delaminated fibers and the extent of thermal damage (heat affected zone and hole overcut) to the workpiece. Both approaches have shown considerable potential of removal of delaminated fibers precisely.