INFLUENCE OF MECHANICAL ACTIVATION AND SPARK PLASMA SINTERING ON THE STRUCTURE AND PROPERTIES OF WC-FE AND WC-NI ALLOYS

Аннотация

The influence of mechanical activation and spark plasma sintering on the structural-phase state and mechanical properties of cobalt-free WC95Fe5 and WC95Ni5 hard alloys was investigated. Powder mixtures were prepared by high-energy milling in a planetary ball mill for 30 and 60 minutes. It was found that increasing the mechanical activation time leads to a decrease in crystallite size to 23.8-32.0 nm and an increase in microstrains to 0.198-0.222%. SPS sintering at temperatures of 1300-1350 °C is accompanied by partial relaxation of the defect structure and crystallite growth. The maximum relative density values were 90% for WC95Fe5 and 89% for WC95Ni5, and microhardness values were 1320 and 1080 HV, respectively. The WC-Fe system was shown to exhibit higher mechanical properties compared to WC-Ni. The obtained results indicate the promise of combining mechanical activation and SPS for producing cobalt-free hard alloys, but require further optimization of consolidation parameters.