Pulsed electric current sintered Fe3Al bonded WC composites

Abstract WC based composites with 5, 10 and 20 vol.% Fe 3 Al binder were consolidated via pulsed electric current sintering (PECS) in the solid state for 4 min at 1200 °C under a pressure of 90 MPa. Microstructural analysis revealed a homogeneous Fe 3 Al binder distribution, ultrafine WC grains and dispersed Al 2 O 3 particle clusters. The WC-5 vol.% Fe 3 Al composite combines an excellent Vickers hardness of 25.6 GPa with very high Young’s modulus of 693 GPa, a fracture toughness of 7.6 MPa m 1/2 and flexural strength of 1000 MPa. With increasing Fe 3 Al binder content, the hardness and stiffness decreased linearly to 19.9 and 539 GPa, respectively with increasing binder content up to 20 vol.%, while the fracture toughness and flexural strength were hardly influenced by the binder content. Compared to WC–Co cemented carbides processed under exactly the same conditions, the WC–Fe 3 Al composites exhibit a substantially higher hardness and Young’s modulus.