Wire electrical discharge machining of 3Y-TZP/Ta ceramic-metal composites

Dense (>98 th%) and homogeneous ceramic/metal composites were obtained by spark plasma sintering (SPS) using ZrO2 and lamellar metallic powder of tantalum (20 vol%) as starting materials. Composites showed a fracture toughness value of 16 MPa m1/2 mainly due to crack bridging of the elastic–plastic deformations of ductile metal particles. This fracture toughness was accompanied by a simultaneous enhancement in damage tolerance and fatigue resistance of 3Y-TZP/Ta composites. Besides exceptional mechanical properties, SPS sintered 3Y-TZP/Ta composites also showed the electrical conductivity suited to wire electrical discharge machining (WEDM). Therefore, they are suitable to be produced in mechanically performant, complex shape components with the required tolerance while reducing machining costs. The aim of this work was the study of the electrical properties of the materials as well as the characteristics of the machining process and the machined surfaces influence on the bending strength of composites. The results show that workpieces can be machined with high accuracy and without a drop in mechanical strength. •Fully dense and homogeneous ceramic-metal composites were successfully fabricated.•Composites showed outstanding value of fracture toughness of 16 MPa m1/2.•3Y-TZP/Ta composites suited to wire electrical discharge machining (WEDM).•WEDM cut specimens showed insignificant degradation in the bending strength.