Polycrystalline diamond compacts with partitioned substrate, polycrystalline diamond table, or both

Abstract

Embodiments of methods for at least partially relieving stress within a polycrystalline diamond (“PCD”) table of a polycrystalline diamond compact (“PDC”) by partitioning the substrate of the PDC, the PCD table of the PDC, or both. Partitioning may be achieved through grinding, machining, laser cutting, electro-discharge machining, or combinations thereof. PDC embodiments including at least one stress relieving partition are also disclosed.

What is claimed is: 
     
         1 . A polycrystalline diamond compact (“PDC”), comprising:
 a substrate; and 
 a polycrystalline diamond (“PCD”) table including a plurality of bonded diamond grains defining a plurality of interstitial regions therebetween, the PCD table bonded to the substrate at an interface, the PCD table including:
 an exterior top surface spaced from the interface; 
 at least one lateral surface extending between the interface and the exterior top surface; 
 a leached region extending inwardly from the exterior top surface and a portion of the at least one lateral surface, at least some of the plurality of interstitial regions of the leached region depleted of at least one interstitial material; 
 an unleached region adjacent to the interface; and 
 a plurality of substantially radially extending grooves formed in the exterior top surface and at least partially defining a plurality of substantially circular segments each of which is free of any of the plurality of substantially radially extending grooves, each of the plurality of substantially radially extending grooves extending laterally inwardly from an outermost portion of the exterior top surface towards an inner portion of the exterior top surface, at least one of the plurality of substantially radially extending grooves including at least one open end. 
 
 
     
     
         2 . The PDC of  claim 1 , wherein the leached region extends inwardly from the plurality of substantially radially extending grooves. 
     
     
         3 . The PDC of  claim 1 , wherein the plurality of substantially radially extending grooves exhibits a depth d 1  and the leached region exhibits a maximum depth d 2  measured inwardly from the exterior top surface, wherein d 1  is greater than d 2 . 
     
     
         4 . The PDC of  claim 1 , wherein at least one of the plurality of substantially radially extending grooves extends to the interface. 
     
     
         5 . The PDC of  claim 4 , wherein at least one of the interface or the exterior top surface is nonplanar. 
     
     
         6 . The PDC of  claim 1 , wherein at least one of the plurality of substantially radially extending grooves extends into the substrate. 
     
     
         7 . The PDC of  claim 1 , wherein at least one of the plurality of substantially radially extending grooves is substantially aligned with and extends along at least a portion of a diameter of the PCD table. 
     
     
         8 . The PDC of  claim 1 , wherein at least one of the plurality of substantially radially extending grooves is offset from a diameter of the PCD table. 
     
     
         9 . The PDC of  claim 1 , wherein the at least one open end includes a first open end laterally spaced from a generally opposing second open end. 
     
     
         10 . The PDC of  claim 1 , wherein at least some of the plurality of substantially radially extending grooves intersect with each other. 
     
     
         11 . The PDC of  claim 10 , wherein the at least some of the plurality of substantially radially extending grooves intersect substantially perpendicularly with each other. 
     
     
         12 . The PDC of  claim 1 , wherein the plurality of substantially radially extending grooves are substantially equally spaced from each other. 
     
     
         13 . The PDC of  claim 1 , further comprising one or more generally circular grooves remote from the outermost portion of the exterior top surface. 
     
     
         14 . The PDC of  claim 1 , wherein at least one of the plurality of substantially radially extending grooves extends through at least a majority of the at least one lateral surface. 
     
     
         15 . The PDC of  claim 1 , wherein each of the plurality of substantially circular segments is free of any grooves. 
     
     
         16 . A method of partitioning a polycrystalline diamond compact (“PDC”), the method comprising:
 providing the PDC including:
 a substrate; and 
 a polycrystalline diamond (“PCD”) table including a plurality of bonded diamond grains defining a plurality of interstitial regions therebetween, the PCD table bonded to the substrate at an interface, the PCD table including:
 an exterior top surface spaced from the interface; 
 at least one lateral surface extending between the interface and the exterior top surface; 
 
 
 cutting the exterior top surface to form a plurality of substantially radially extending grooves that at least partially define a plurality of substantially circular segments each of which is free of any of the plurality of substantially radially extending grooves, each of the plurality of substantially radially extending grooves extending laterally inwardly from an outermost portion of the exterior top surface towards an inner portion of the exterior top surface spaced from the outermost portion, at least one of the plurality of substantially radially extending grooves including at least one open end; and 
 leaching a portion of the PCD table to deplete at least one interstitial material from at least some of the plurality of interstitial regions to form a leached region, the leached region extending inwardly from the exterior top surface and a portion of the at least one lateral surface. 
 
     
     
         17 . The method of  claim 16 , wherein the act of leaching a portion of the PCD table is performed before the act of cutting the exterior top surface. 
     
     
         18 . The method of  claim 16 , wherein the act of leaching a portion of the PCD table is performed after the act of cutting the exterior top surface. 
     
     
         19 . A rotary drill bit, comprising:
 a bit body configured to engage a subterranean formation; and   a plurality of polycrystalline diamond cutting elements mounted to the bit body, at least one of the plurality of polycrystalline diamond elements including:
 a substrate; 
 a polycrystalline diamond (“PCD”) table including a plurality of bonded diamond grains defining a plurality of interstitial regions therebetween, the PCD table bonded to the substrate at an interface, the PCD table including:
 an exterior top surface spaced from the interface; 
 at least one lateral surface extending between the interface and the exterior top surface; 
 a leached region extending inwardly from the exterior top surface and a portion of the at least one lateral surface, at least some of the plurality of interstitial regions of the leached region depleted of at least one interstitial material; 
 an unleached region adjacent to the interface; and 
 a plurality of substantially radially extending grooves formed in the exterior top surface and at least partially defining a plurality of substantially circular segments each of which is free of any of the plurality of substantially radially extending grooves, each of the plurality of substantially radially extending grooves extending laterally inwardly from an outmost portion of the exterior top surface at least partially towards an inner portion of the exterior top surface, at least one of the plurality of substantially radially extending grooves includes at least one open end. 
 
   
     
     
         20 . A polycrystalline diamond compact (“PDC”), comprising:
 a substrate; and 
 a polycrystalline diamond (“PCD”) table including a plurality of bonded diamond grains defining a plurality of interstitial regions therebetween, the PCD table bonded to the substrate at an interface, the PCD table including:
 an exterior top surface spaced from the interface; 
 at least one lateral surface extending between the interface and the exterior top surface; 
 a leached region extending inwardly from the exterior top surface and a portion of the at least one lateral surface, at least some of the plurality of interstitial regions of the leached region depleted of at least one interstitial material; 
 an unleached region adjacent to the interface; and 
 a plurality of laterally extending grooves formed in the exterior top surface and at least partially defining a plurality of substantially circular segments each of which is free of any of the plurality of laterally extending grooves, each of the plurality of laterally extending grooves substantially equally spaced from each other at an acute angle, each of the plurality of laterally extending grooves extending laterally inwardly from an outermost portion of the exterior top surface towards an inner portion of the exterior top surface, at least one of the plurality of substantially radially extending grooves including at least one open end at the outermost portion of the exterior top surface.