Composites from WC powders sputter-deposited with iron rich binders

Composite powders of tungsten carbide (WC) and iron rich binder were prepared by an innovative approach, which consists in sputtering of a metallic binder on the tungsten carbide particles. The phase composition, microstructure and mechanical behaviour of WC coated powder composites with binder contents from 6 to 9 wt.% were characterized. η-Phase is early formed during sintering and its effect on the mechanical behaviour was investigated and related to the microstructure and atomic structure. The results show that the presence of η-phase has not a hazardous role in toughness as is previewed in conventional cemented carbide. Despite the presence of η-phase, a good compromise between toughness and hardness was attained in composites prepared from iron rich binders sputtered on WC powders.