Abstract: The failure analysis of the geological exploration bit body and alloy tooth(WC-Co Cemented carbides)by using scanning electron microscopy was studied. It was concluded that the failure mechanism of the bit body on impact end was the impactfatigue, and the spline failure mode was crushing spalling after severe plastic deformation. Through analyzing the three failure modes (alloy tooth shedding, fracture, wearing), the main reason of alloy tooth failure was overlapping effect of cable spalling, abrasive wear, impact fatigue and impact thermal fatigue.

Key words: failure analysis, cemented carbide tooth, physics exploration bit