The measurement of heat distribution in stereolithography electrodes during electro-discharge machining

Early work by the authors explored the potential for manufacture of electrodischarge machining (EDM) electrodes, using rapid prototyping (RP) technologies. A number of possible routes were identified to provide an integrated system from computer aided design (CAD) data through to production tooling. One such route is the processing of stereolithography (SL) RP models by electro-depositing copper onto the metallized surface. This strategy provides a process route from model to tool with minimum manual intervention. Initial studies using thin-coated SL models for EDM have identified a limitation to application due to heat build up in the electrode. Currently, the electrodes can be used at low material removal rates (MRR), commonly known as semi-roughing or finishing cuts. Higher MRR generates greater heat at the cutting face which causes failure of the RP electrodes. This failure is believed to occur through a combination of delamination, thinning and distortion of the electrode. The heat distribution and associated failure modes for these electrodes are being investigated to determine how the machining performance can be improved.