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Hard materials, in particular tungsten carbide (WC) hard material has been used in many industries as cutting tool and abrasive materials. For improving toughness, binders are added into carbide materials. The effect of Co as binder on the mechanical properties in the nanosized WC was discussed. The hardness and fracture toughness were also investigated using 30 kgf load Vickers indenter. The nanosized WC-8, 10 and 12 vol.% Co composites were successfully fabricated without grain growth by high frequency induction heated sintering (HFIHS), which is the rapid sintering method, due to short sintering time 1140°C. The nanosized WC–Co composites fabricated by HFIHS have better mechanical properties than WC–Co composite fabricated by commercial sintering.

Nano-sized hard materials have to be developed for improving mechanical properties. Nowadays, high energy mechanical milling (HEMM) method is widely used to fabricate nano-sized powders. The mechanical properties increase with decreasing grain size. However, grain growth has occurred by conventional sintering method with long sintering time. In this work, high-frequency induction heated sintering (HFIHS) was used to fabricate highly dense nano-sized WC-10vol.%Nicrobraz 30, 150 and LC composites for short sintering time without grain-growth. Therefore, control of grain growth during sintering is one of the keys to the commercial success of nano-structured cemented carbide composites. After sintering, relative density of WC-10vol.%Nicrobraz 30, 150 and LC composites were 99.9%, 98.7% and 98.0%, respectively. The grain sizes confirmed that full-width at half maximum (FWHM) was used from the result of XRD. The highly dense nano-sized WC-10vol.%Nicrobraz 30, 150 and LC composites were fabricated successfully using HEMM and HFIHS equipments.