Electrical discharge machining of metal doped Y-TZP/TiC nanocomposites

Abstract Electrical discharge machinable dispersion ceramics offer an extraordinary combination of properties such as high hardness, wear resistance, strength and toughness. Furthermore they enable the economic manufacturing of complex shaped parts overcoming the limits these properties imply for their manufacturing by conventional techniques. This study investigates the influence of metallic nanosized inclusions on the ED-machinability and the mechanical properties of zirconia-TiC based ceramics. A 2.6 mol% yttria stabilized zirconia with 24 vol.% TiC was doped with 2 vol.% nanosize inclusions of iron, nickel and cobalt. Samples were hot pressed at 1400 °C and 50 MPa. Mechanical and electrical properties were measured. Die sink ED-machining was performed and assessed in terms of processing speed and surface quality. Metallic inclusions strongly influenced powder processing and sintering behavior and thus the mechanical properties. Metallic particles reduced the electrical conductivity of the materials and deteriorated ED-machining performance.