Effects of LaB6 addition on the microstructure and mechanical properties of ultrafine grained WC–10Co alloys

The ultrafine grain WC–10Co alloys were prepared by the planetary ball milling method and low pressure sintering. The effects of LaB6 addition on the microstructure and mechanical properties of the based alloys were investigated by X-ray diffraction, scanning electron microscope and mechanical property testing. It has been shown that the grain growth and regularization of WC particles occur simultaneous with the addition of LaB6. Adding suitable amount of LaB6 improves the density, hardness and fracture toughness of the ultrafine WC–10Co alloys, and decreases the volume fraction of Co3W3C phase in ultrafine WC–10Co alloys.

Research highlightsThe authors first reported the ultrafine grain WC–10Co alloys with minor LaB6 addition. The research results show that the obvious grain growth and regularization of WC particles of the based alloys occur simultaneous with the addition of LaB6. Adding proper LaB6 improves the density, hardness and fracture toughness of the ultrafine WC–10Co alloys, and decreases the volume fraction of Co3W3C phase in ultrafine WC–10Co alloys.