Ultra-hard material cutting elements, methods of forming the same and bits incorporating the same

Abstract

The present disclosure relates to cutting tools incorporating polycrystalline diamond bodies used for subterranean drilling applications, and more particularly, to a polycrystalline diamond body joined to a substrate by a fastening member to form a cutting element. The polycrystalline diamond body may be binderless polycrystalline diamond, non-metal catalyst polycrystalline diamond, leached polycrystalline diamond, carbonate polycrystalline diamond or polycrystalline cubic boron nitride. The polycrystalline diamond body includes an aperture and a fastening member extending through the aperture and metallurgically bonded to the substrate by a HPHT process.

What is claimed is: 
     
         1 . A cutting element, comprising:
 a polycrystalline diamond body having a working surface and an interface surface opposite the working surface;
 an aperture in the polycrystalline diamond body extending between the working surface and the interface surface; 
 a substrate having an interface surface; 
 a fastening element extending through the aperture in the polycrystalline diamond body; and 
 a metallurgical bond between at least a portion of the fastening element and at least a portion of the substrate at an interface between the fastening element and the substrate. 
   
     
     
         2 . The cutting element of  claim 1 , wherein the polycrystalline diamond body is selected from the group of bodies consisting essentially of binderless polycrystalline diamond bodies, non-metal catalyst polycrystalline diamond, leached polycrystalline diamond, carbonate polycrystalline diamond, and polycrystalline cubic boron nitride. 
     
     
         3 . The cutting element of  claim 1 , wherein at least a portion of the polycrystalline diamond body is selected from the group of bodies consisting essentially of binderless polycrystalline diamond bodies, non-metal catalyst polycrystalline diamond, leached polycrystalline diamond, carbonate polycrystalline diamond, and polycrystalline cubic boron nitride. 
     
     
         4 . The cutting element of  claim 1 , wherein the fastening member comprises a first carbide material and the substrate comprises a second carbide material, the first carbide material being different than the second carbide material. 
     
     
         5 . The cutting element of  claim 1 , wherein the fastening member comprises a first carbide material and the substrate comprises a second carbide material, the first carbide material being the same as the second carbide material. 
     
     
         6 . The cutting element of  claim 1 , wherein the fastening member comprises a cemented tungsten carbide material having a cobalt binder matrix. 
     
     
         7 . The cutting element of  claim 1 , wherein the metallurgical bond is formed by high pressure high temperature sintering producing a pressure between approximately 5.5 GPa and 7 GPa and a temperature between approximately 1340° C. and 1550° C. 
     
     
         8 . The cutting element of  claim 1 , further comprising a metallurgical bond between at least a portion of the fastening member and at least a portion of the polycrystalline diamond body. 
     
     
         9 . The cutting element of  claim 1 , wherein the aperture is a hole extending between the working surface and the interface surface of the polycrystalline diamond body. 
     
     
         10 . The cutting element of  claim 9 , further comprising a cylindrical recess in the carbide substrate extending down from the interface surface of the substrate, wherein the fastening element is a pin having a head portion and a shaft portion extending from the head portion, the shaft portion extending through the hole and into the cylindrical recess, and the head portion overhanging a portion of the working surface. 
     
     
         11 . The cutting element of  claim 1 , wherein the aperture is a notch extending along at least a portion of the periphery of the polycrystalline diamond body. 
     
     
         12 . The cutting element of  claim 11 , wherein the fastening element is a wedge-shaped clamp generally complementary to the notch. 
     
     
         13 . The cutting element of  claim 1 , further comprising:
 a plurality of hemispherical depressions in the interface surface of the substrate, wherein the depressions are disposed in a circular pattern; and   a plurality of ball bearings housed in the hemispherical depressions, wherein the interface surface of the thermally stable polycrystalline body is slidably engaged with the plurality of ball bearings such that the polycrystalline diamond body is rotatably joined to the substrate.   
     
     
         14 . A drill bit comprising a body having a cutting element as in  claim 1  mounted thereon. 
     
     
         15 . A method of joining a thermally stable polycrystalline diamond body to a substrate with a fastening member, the method comprising:
 obtaining a thermally stable polycrystalline diamond body having an aperture, wherein the thermally stable polycrystalline diamond body is selected from the group of bodies consisting essentially of binderless polycrystalline diamond bodies, non-metal catalyst polycrystalline diamond bodies, leached polycrystalline diamond bodies, carbonate polycrystalline diamond, and polycrystalline cubic boron nitride;   obtaining a substrate;   inserting the fastening member into the aperture; and   high pressure, high temperature sintering the fastening member, the thermally stable polycrystalline diamond body, and the substrate to form a metallurgical bond between the fastening member and the substrate.   
     
     
         16 . The method of  claim 15 , wherein obtaining the thermally stable polycrystalline diamond body comprises forming the thermally stable polycrystalline diamond body and forming the aperture in the thermally stable polycrystalline diamond body. 
     
     
         17 . The method of  claim 16 , wherein obtaining the thermally stable polycrystalline diamond body comprises sintering diamond particles and a non-metal catalyst at high temperature and high pressure to form non-metal catalyst polycrystalline diamond. 
     
     
         18 . The method of  claim 16 , wherein obtaining the thermally stable polycrystalline diamond body comprises subjecting carbon to an ultra-high pressure, high temperature sintering process without a catalyst material, to form binderless polycrystalline diamond. 
     
     
         19 . The method of  claim 16 , wherein obtaining the thermally stable polycrystalline diamond body comprises:
 subjecting diamond powder and a catalyst to a high pressure, high temperature sintering process to form a polycrystalline diamond body; and   treating a portion of the polycrystalline diamond body to remove a substantial portion of the catalyst material in interstitial regions between the bonded diamond crystals to form leached polycrystalline diamond.   
     
     
         20 . The method of  claim 15 , wherein high pressure, high temperature sintering the fastening member, the thermally stable polycrystalline diamond body, and the substrate to form a metallurgical bond between the fastening member and the substrate comprises producing a pressure between approximately 5.5 GPa and 7 GPa and a temperature between approximately 1340° C. and 1550° C.