Co drifts between cemented carbides having various WC grain sizes

• Binder drifts in WC–Co couples with different WC mean grain sizes were examined.
• Noticeable Co drifts occur from coarse-grain into fine-grain regions during sintering.
• Co drifts rise when the difference between WC grains sizes increases.

Functionally graded cemented carbides obtained on the basis of capillarity phenomena can be very important for numerous applications and are expected to substitute conventional WC–Co cemented carbides. Drifts of liquid Co-based binders in couples of model WC–Co alloys with different WC mean grain sizes sintered together were examined. Noticeable Co drifts occur from coarse-grain into fine-grain regions of the model alloys due to different capillary forces. The Co drifts become more pronounced when the difference between WC mean grains sizes of the coarse-grain region and fine-grain region increases.