Polycrystalline diamond cutters with enhanced impact resistance

Abstract

Disclosed is an abrasive compact layer wherein the compact layer contains >30% by volume large single crystal diamonds, and wherein said diamond crystals are characterized as having a well defined cubo-octahedral diamond shapes (aspect ratios>0.87), and high toughness index crystals (TI>50).

1 . A preform cutting element comprising a body of a superhard polycrystalline material comprising a plurality of diamond crystals, wherein said diamond crystals having 
 a particle size distribution in the range of about 60 to 100 microns;    a toughness index of at least about 50; and    an average aspect ratio of 0.80 or greater.    
     
     
         2 . The cutting element of  claim 1 , wherein said polycrystalline body comprises a plurality of diamond crystals having a particle size distribution in the range of about 70 to 90 microns.  
     
     
         3 . The cutting element of  claim 2 , wherein said polycrystalline body comprises a plurality of diamond crystals having an average aspect ratio of at least 0.85.  
     
     
         4 . The cutting element of  claim 2 , wherein said polycrystalline body comprises a plurality of diamond crystals having a toughness index of at least about 60.  
     
     
         5 . A tool comprising the preform cutting element of  claim 1 .  
     
     
         6 . The preform cutting element of  claim 1 , wherein the cutting element is mounted upon a cutting face of a drill bit.  
     
     
         7 . The preform cutting element of  claim 1 , further comprising a cutting surface adapted for use as a cutting insert in a machining operation.  
     
     
         8 . The preform cutting element of  claim 1 , further comprising an additive material prior to formation of the cutting element in a high pressure high temperature operation.