Modified cutters

Abstract

A modified cutting element that includes a base portion, an ultrahard layer disposed on said base portion, and at least one modified region disposed adjacent to a cutting face of the cutter is described. In certain applications, the ultrahard layer comprises thermally stable polycrystalline diamond.

1 . A cutter comprising: 
 a base portion;    an ultrahard layer disposed on said base portion; and    at least one modified region disposed adjacent to a cutting face of the cutter.    
   
   
       2 . The cutter of  claim 1 , wherein the ultrahard layer comprises thermally stable polycrystalline diamond.  
   
   
       3 . The cutter of  claim 1 , further comprising a beveled edge disposed on said cutting face.  
   
   
       4 . The cutter of  claim 3 , wherein the beveled edge has a thickness 0.005 inches to 0.050 inches.  
   
   
       5 . A drill bit comprising: 
 a bit body; and    at least one cutter, the at least one cutter comprising a base portion, an ultrahard layer disposed on said base portion, and at least one modified region disposed adjacent to a cutting face of the cutter.    
   
   
       6 . The drill bit of  claim 5 , wherein the ultrahard layer comprises thermally stable polycrystalline diamond.  
   
   
       7 . The drill bit of  claim 5 , further comprising a beveled edge disposed on said cutting face.  
   
   
       8 . The drill bit of  claim 7 , wherein the beveled edge has a thickness 0.005 inches to 0.050 inches.  
   
   
       9 . A method of drilling, comprising: 
 contacting a formation with a drill bit, wherein the drill bit comprises a bit body; and    at least one cutter, the at least one cutter comprising a base portion, an ultrahard layer disposed on said base portion, and at least one modified region disposed adjacent to a cutting face of the cutter.    
   
   
       10 . A method of forming a modified cutter, comprising: 
 providing an unmodified cutter, the unmodified cutter comprising an ultrahard layer disposed on a base portion;    removing a selected portion of the ultrahard layer, adjacent to a cutting face of said cutter.    
   
   
       11 . The method of  claim 10 , wherein removing comprises electrical discharge machining the ultrahard layer.  
   
   
       12 . The method of  claim 10 , wherein the ultrahard layer comprises thermally stable polycrystalline diamond.