Development of Electrical Discharge Machinable ZTA Ceramics with 24 vol% of TiC, TiN, TiCN, TiB2 and WC as Electrically Conductive Phase



In order to develop ED-machinable ceramics with high strength, toughness and wear resistance, ZTA was chosen as matrix material. A dispersion of 24 vol% electrically conductive phase (TiC, TiN, TiCN, TiB2 and WC) was added. These composites were hot pressed for 1 h at 60 MPa and temperatures ranging from 1475°C to 1550°C. Mechanical and electrical properties were investigated. The influence of the electrically conductive phase on the surface quality after EDM was analyzed. The mechanical properties and machining quality were found to depend significantly on the type of conductive phase added. Machining of a complex shaped ZTA-TiC component was demonstrated.