EVALUATION OF OXIDATION AND MECHANICAL PROPERTIES OF THE NANO-SIZED WC-10NICROBRAZ COMPOSITES CONSOLIDATED BY HIGH FREQUENCY INDUCTION HEATED SINTERING

摘要

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-l0vol.%Nicrobraz 30, 150 and LC composites were fabricated successfully using HEMM and HFIHS equipments.