Cutter protection during leaching process

Abstract

A method of forming a thermally stable cutting element may include providing a cutting element including a substrate fixed to a polycrystalline diamond cutting table; enclosing the substrate and at least a portion of the polycrystalline diamond cutting table within a protective element to form a partially enclosed cutting element; exerting a compressive squeeze on the cutting element of about 5-25%; and exposing the partially enclosed cutting element to a leaching solution so that at least part of an unenclosed portion of the polycrystalline diamond table is in contact with the leaching solution.

What is claimed is: 
     
         1 . A method of treating a cutting element, comprising:
 providing a cutting element comprising polycrystalline diamond fixed to a substrate;   enclosing the substrate and at least a portion of the polycrystalline diamond within a protective element to form a partially enclosed cutting element;   exerting a compressive squeeze on the cutting element of about 5-25%; and   exposing the partially enclosed cutting element to a leaching solution so that at least part of an unenclosed portion of the polycrystalline diamond is in contact with the leaching solution.   
     
     
         2 . The method of  claim 1 , wherein enclosing the substrate and at least a portion of the polycrystalline diamond within a protective element comprises inserting a portion of the cutting element into a pre-molded sleeve. 
     
     
         3 . The method of  claim 2 , wherein the exerting comprises securing the substrate and at least a portion of the polycrystalline diamond cutting within the pre-molded sleeve with at least one snap ring. 
     
     
         4 . The method of  claim 1 , wherein the protective element comprises at least one material selected from the group consisting of FKM fluoroelastomers, polychloroprene, chlorinated polyethylene, chlorosulfonated polyethylene, epichlorohydrin, fluorosilicone, hydrofluorocarbon, fluoroelastomers, halobutyl elastomers, and FFKM perfluoroelastomers. 
     
     
         5 . The method of  claim 1 , wherein enclosing the substrate and at least a portion of the polycrystalline diamond within a protective element comprises coating the substrate and at least a portion of the polycrystalline diamond table with a curable liquid composition. 
     
     
         6 . The method of  claim 1 , wherein enclosing the substrate and at least a portion of the polycrystalline diamond within a protective coating comprises securing the substrate and at least a portion of the polycrystalline diamond table within an inert housing by a sealing element. 
     
     
         7 . The method of  claim 4 , wherein prior to coating the substrate and at least a portion of the polycrystalline diamond with a curable liquid to form a coating thereon, at least a portion of the polycrystalline diamond is masked with a masking material to prevent being coated with the curable liquid. 
     
     
         8 . The method of  claim 7 , wherein the masking material is removed after the application of the curable liquid coating and prior to exposing the partially enclosed cutting element to the leaching solution. 
     
     
         9 . The method of  claim 2 , wherein the diameter of the molded sleeve is less than the diameter of the substrate and polycrystalline diamond table. 
     
     
         10 . The method of  claim 1 , wherein the leaching solution comprises an acid selected from the group consisting of nitric acid, hydrofluoric acid, and mixtures thereof. 
     
     
         11 . The method of  claim 1 , wherein exposing the partially enclosed cutting element to a leaching solution comprises suspending the cutting element within a leaching solution via magnetic components disposed within the protective element. 
     
     
         12 . The method of  claim 1 , wherein exposing the partially enclosed cutting element to the leaching solution occurs at least in part under elevated pressure, elevated temperature, or ultrasonic conditions. 
     
     
         13 . A protected cutting element, comprising:
 a cutting element comprising polycrystalline diamond fixed to a substrate; and   a protective element enclosing the substrate and at least a portion of the polycrystalline diamond and exerting a compressive squeeze of about 5-25% on the cutting element.   
     
     
         14 . The protected cutting element of  claim 13 , wherein the protective element comprises at least one snap ring that exerts the compressive squeeze. 
     
     
         15 . The protected cutting element of  claim 13 , wherein the protective element comprises at least one material selected from the group consisting of FKM fluoroelastomers, polychloroprene, chlorinated polyethylene, chlorosulfonated polyethylene, epichlorohydrin, fluorosilicone, hydrofluorocarbon, fluoroelastomers, halobutyl elastomers, and FFKM perfluoroelastomers. 
     
     
         16 . The protected cutting element of  claim 15 , wherein the protective element comprises at least one material selected from the group consisting of FKM fluoroelastomers and FFKM perfluoroelastomers. 
     
     
         17 . The protected cutting element of  claim 13 , wherein the protective element comprises a pre-molded sleeve that exerts the compressive squeeze. 
     
     
         18 . A method of treating a cutting element, comprising:
 providing a cutting element comprising polycrystalline diamond attached to a substrate;   enclosing the substrate and at least a portion of the polycrystalline diamond within a protective element comprising at least one FFKM perfluoroelastomeric material to form a partially enclosed cutting element; and   exposing the partially enclosed cutting element to a leaching solution so that at least part of an unenclosed portion of the polycrystalline diamond is in contact with the leaching solution.   
     
     
         19 . The method of  claim 18 , further comprising using a snap ring to secure the substrate and at least a portion of the polycrystalline diamond cutting table within the protective element. 
     
     
         20 . The method of  claim 18 , wherein the protective element is a pre-molded sleeve.