Numerical Investigation of the EDM Induced Temperature Field in a Composite Ceramic

The combination of high chemical and thermal durability with high hardness and strength is the main reason for the increasing use of ceramics in industry. However, these benefits lead to serious challenges for conventional manufacturing processes, which are often limited due to the mechanical properties of the workpiece material. Because of its working principle, electrical discharge machining (EDM) is almost independent from the mechanical workpiece properties. Nevertheless, the thermal loadings, which are caused by electrical discharges, result in different modifications on the surface and in sub-surface layers. These induced modifications define the surface integrity, which in turn determines the functional properties of a workpiece. Besides the intended rim zone modifications damages also occur. For a more detailed understanding of the occurring damages within the arising heat affected zone (HAZ), a heat transfer simulation for a single discharge on an alumina/zirconia/tungsten carbide ceramic was conducted in this work.