摘要 |
A diamond cutting element (10) for use on an earth boring drill bit, such as a rotary drag bit. The cutting element is predominantly comprised of a diamond cutting structure (12) attached to either a reduced-volume substrate (14) or directly to a bit body, optionnally using a carrier structure mounted to the bit body. With such a configuration, stress between dissimilar materials, such as the substrate and the cutting structure, is reduced or entirely eliminated. Moreover, only the diamond cutting structure contacts the formation during drilling resulting in lower friction, lower temperatures and lower wear rates of the cutting elements. The diamond cutting structure may also be polished and include one or more intermal passageways that extend into the diamond through which fluids may be passed to transfer heat from the cutting element during drilling. |