EDM machinability and surface roughness analysis of TiB2 using copper electrodes

Titanium diboride (TiB2) is a sintered ceramic material which has a high industrial interest due to its excellent mechanical properties, such as immense hardness, elastic modulus, and abrasion resistance. Unlike most ceramics, this material can be machined by using an electrical discharge machining (EDM) process because of its good thermal and electrical conductivity. In this present study the applicability of an EDM process for manufacturing titanium diboride is analysed. To do that, the influence of EDM parameters is studied on three of the most important technological characteristics in EDM: material removal rate (MRR), electrode wear (EW) and surface roughness (Ra). Results confirm that the most influential factor on MRR and Ra is the current intensity whereas in the case of EW, it is the pulse time. Additionally, the control of these parameters allows technological tables to be obtained in order to determine the optimum operating conditions. Such technological tables exist for the case of steels but they do not exist for TiB2, in which the optimal conditions are to be determined experimentally.