摘要 |
A cutting element for a rotary drill bit comprises a thin cutting table of polycrystalline diamond having a front cutting face and a rear surface bonded to a tungsten carbide substrate. The substrate incorporates one or more thin barrier layers which extend at least partly through the thickness of the substrate in a direction transverse to its front surface. Each barrier layer is formed of a material, such as nickel, which is more ductile than the material of the substrate, but is metallurgically compatible with it.
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