PCD Elements And Process For Making The Same

Abstract

Catalyst in a sintered polycrystalline diamond (PCD) structure is dissolved in at least a portion of the structure by a liquid solvent metal. The structure is infused with the heated solvent and the solvent infiltrates interstitial spaces between consolidated diamond grains to contact residual catalyst from the sintering process. The dissolved catalyst passes to the bulk solvent and the solvent replaces the catalyst in the interstitial spaces.

1 . A consolidated diamond compact with interstitial spaces comprising:
 a first portion of the compact with a catalyst metal in the interstitial spaces; and   a second portion of the compact with a solvent metal in the interstitial spaces.   
     
     
         2 . The consolidated diamond compact of  claim 1  where the catalyst volume in the second portion is less than the solvent metal volume in the second portion. 
     
     
         3 . The consolidated diamond compact of  claim 1  where the catalyst volume in the second portion is less than 25% of the combined volume of catalyst and solvent in the second portion. 
     
     
         4 . A consolidated diamond compact comprising sintered diamond, a catalyst metal, a solvent metal, a ground-engaging outer surface, a working portion including the ground-engaging outer surface, and a base portion remote from the ground-engaging outer surface, the working portion including a greater volume of solvent metal than catalyst metal, and the base portion including a greater volume of catalyst metal than solvent metal. 
     
     
         5 . A consolidated diamond compact comprising sintered diamond, a catalyst metal capable of acting as a catalyst for sintered diamond, and a solvent metal capable of dissolving the catalyst metal. 
     
     
         6 . The consolidated diamond compact of  claim 5  where the catalyst metal is a Type VIII metal or metal alloy. 
     
     
         7 . The consolidated diamond compact of  claim 5  where the catalyst metal is cobalt or a cobalt alloy. 
     
     
         8 . The consolidated diamond compact of  claim 5  where the solvent metal is at least one from a group consisting substantially of gallium, tin, indium, titanium, molybdenum, iron, zirconium, sodium, potassium and mercury. 
     
     
         9 . The consolidated diamond compact of  claim 5  where the solvent metal is tin or a tin alloy. 
     
     
         10 . The consolidated diamond compact of  claim 5  where the solvent metal is gallium or a gallium alloy. 
     
     
         11 . The consolidated diamond compact of  claim 5  where the solvent metal is galinstan. 
     
     
         12 . The consolidated diamond compact of  claim 5  where the solvent metal is nonpolar. 
     
     
         13 . The consolidated diamond compact of  claim 5  where the solvent metal has a lower melting point than the catalyst. 
     
     
         14 . The consolidated diamond compact of  claim 5  where the solvent metal is non-aqueous. 
     
     
         15 . The consolidated diamond compact of  claim 5  where the catalyst metal has at least 2% solubility in the solvent metal when heated above 600° C. 
     
     
         16 . The consolidated diamond compact of  claim 5  where the diamond compact is bonded to a substrate of tungsten carbide. 
     
     
         17 . The consolidated diamond compact of  claim 5  where the diamond compact is a face of a cutter for drag bits. 
     
     
         18 . A consolidate diamond compact comprising sintered diamond, a first metal, and a second metal, wherein at 700° C. the first metal is a solid and the second metal is liquid. 
     
     
         19 . The consolidate diamond compact of  claim 18  where the first metal is a catalyst for the sintered diamond and the second metal is a solvent for the first metal. 
     
     
         20 . The consolidate diamond compact of  claim 18  where the first metal is cobalt or a cobalt alloy. 
     
     
         21 . The consolidated diamond compact of  claim 18  where the second metal is at least one from a group consisting substantially of gallium, tin, indium, titanium, molybdenum, iron, zirconium, sodium, potassium and mercury. 
     
     
         22 . The consolidated diamond compact of  claim 18  where the second metal is gallium or a gallium alloy. 
     
     
         23 . The consolidated diamond compact of  claim 18  where the second metal is tin or a tin alloy. 
     
     
         24 . The consolidated diamond compact of  claim 18  where the second metal is galinstan. 
     
     
         25 . A drag bit comprising a plurality of cutters, where at least one of the cutters includes the consolidated diamond compact in accordance with  claim 18 . 
     
     
         26 . A diamond table for a cutter comprising a base region for attachment to a substrate and including a Group VIII catalyst metal, a ground-engaging working region including a solvent metal and a smaller concentration of the catalyst metal than in the base region. 
     
     
         27 . The diamond table of  claim 26  where the catalyst metal is cobalt or a cobalt alloy. 
     
     
         28 . The diamond table of  claim 26  previous claim where the second metal is at least one from a group consisting substantially of gallium, tin, indium, titanium, molybdenum, iron, zirconium, sodium, potassium and mercury. 
     
     
         29 . The diamond table of  claim 26  where the second metal is gallium or a gallium alloy. 
     
     
         30 . The diamond table of  claim 26  where the second metal is tin or a tin alloy. 
     
     
         31 . The diamond table of  claim 26  where the second metal is galinstan. 
     
     
         32 . A compact for use in a ground-engaging member comprising a substrate and a table bonded to the substrate, the table having interstitial spaces where at least a portion of the interstitial spaces are occupied by a solvent metal. 
     
     
         33 . The compact of  claim 32  including a catalyst metal in the interstitial spaces. 
     
     
         34 . The compact of  claim 33  where the catalyst metal includes cobalt at the primary constituent. 
     
     
         35 . The compact of  claim 33  where the solvent metal is a solvent for the catalyst metal. 
     
     
         36 . The compact of the  claim 32  where the solvent metal includes gallium as the primary constituent. 
     
     
         37 . The compact of  claim 32  where the solvent metal includes tin as the primary constituent. 
     
     
         38 . The compact of  claim 32  where the solvent metal includes galinstan as the primary constituent. 
     
     
         39 . The compact of  claim 32  where the solvent metal is a liquid at 700° C. 
     
     
         40 . The compact of  claim 32  where the table includes sintered diamond grains. 
     
     
         41 . The compact of  claim 32  where a portion of the table has less catalyst by weight than solvent. 
     
     
         42 . The compact of  claim 32  where the solvent metal is one or more metal or alloy of a metal selected from the metal group that includes gallium, tin, sodium, potassium and mercury. 
     
     
         43 . The compact of  claim 32  where the substrate is coated with a metal that limits degradation of the substrate by contact with the gallium. 
     
     
         44 . The compact of  claim 32  where the coating is sputter coated on the substrate surface. 
     
     
         45 . A cutting element comprising a substrate, a diamond table including a catalyst material and a solvent in interstitial spaces, the diamond table having an inner portion secured to the substrate and an outer portion opposite the substrate to engage earthen material in use, the catalyst material forming a greater weight percentage of the inner portion than of the outer portion, and the solvent forming a greater weight percentage of the outer portion than of the inner portion. 
     
     
         46 . The cutting element of  claim 45  where the solvent in the outer portion is greater than the catalyst in the outer portion. 
     
     
         47 . The cutter of  claim 45  where the catalyst material includes cobalt as the primary constituent. 
     
     
         48 . The cutter of  claim 45  where the solvent material is a solvent for the catalyst metal. 
     
     
         49 . The cutter of  claim 45  where the solvent includes gallium as the primary constituent. 
     
     
         50 . The cutter of  claim 45  where the solvent includes tin as the primary constituent. 
     
     
         51 . The cutter of  claim 45  where the solvent includes galinstan as the primary constituent. 
     
     
         52 . The cutter of  claim 45  where the solvent is a liquid at 700° C. 
     
     
         53 . A sintered polycrystalline diamond (PCD) structure comprising a least one region adjacent a working surface with less catalyst occupying the interstices between the bonded diamond grains than a metal with a lower melting temperature. 
     
     
         54 . A cutting element comprising a substrate and a diamond table secured to the substrate, the diamond table including interstitial spaces containing a catalyst material, and an outer portion to contact earthen material including a solvent in the interstitial spaces of greater volume than the catalyst material. 
     
     
         55 . A method for treating a sintered diamond to remove a catalyst comprising:
 heating a solvent; and   infusing at least a portion of the sintered diamond with the solvent to replace at least a portion of a catalyst metal within the sintered diamond.   
     
     
         56 . The method of  claim 55  where the solvent is selected from a group consisting of one or more of a metal solvent, a nonpolar solvent and a non-aqueous solvent. 
     
     
         57 . The method of  claim 55  where infusing the diamond includes displacing a catalyst in interstitial spaces between diamond grains with the solvent. 
     
     
         58 . The method of  claim 55  where the catalyst includes cobalt. 
     
     
         59 . The method of  claim 55  where infusing the sintered diamond includes immersing at least a portion of the diamond in the solvent. 
     
     
         60 . The method of  claim 55  where infusing the sintered diamond includes at least a portion of the diamond contacting a porous body immersed in the solvent that wicks the solvent material onto the diamond. 
     
     
         61 . The method of  claim 55  where the solvent is tin or a tin alloy. 
     
     
         62 . The method of  claim 55  including applying a layer to at least the portion of the diamond immersed in the liquid solvent metal to limit the formation of solvent metal compounds that limit infusion of solvent into the diamond. 
     
     
         63 . The method of  claim 62  where the layer includes one or more metals selected from the group of gallium, tin and indium. 
     
     
         64 . The method of  claim 55  where the solvent dissolves the catalyst in the interstitial spaces when infusing the diamond in the heated solvent. 
     
     
         65 . The method of  claim 55  where the solvent is heated to a temperature between 600° C. and 750° C. 
     
     
         66 . The method of  claim 55  where the solvent is heated in a reduced oxygen environment to a temperature between 1000° C. and 1500° C. 
     
     
         67 . The method of  claim 55  where the infusing of the heated solvent metal is continued until in the portion of the sintered diamond infused with the heated solvent metal the volume of catalyst is less than the volume of solvent. 
     
     
         68 . A method of making a diamond table comprising heating and pressuring polycrystalline diamond grains in the presence of a catalyst metal to form a sintered diamond compact, exposing the diamond compact to a solvent metal that dissolves and at least partially replaces the catalyst metal in the diamond compact. 
     
     
         69 . The method of  claim 68  including heating the solvent metal to dissolve and at least partially replace the catalyst metal. 
     
     
         70 . The method of  claim 69  wherein exposing the diamond compact includes immersing at least a portion of the diamond compact in a bath of the solvent metal. 
     
     
         71 . The method of  claim 69  wherein the solvent metal includes at least one from a group consisting essentially of gallium, titanium, molybdenum, indium, iron, tin, zirconium, sodium, potassium, and mercury. 
     
     
         72 . The method of  claim 69  wherein the catalyst metal is cobalt or a cobalt alloy. 
     
     
         73 . A method of making a diamond table comprising heating and pressuring polycrystalline diamond grains in the presence of a catalyst metal to form a sintered diamond compact, and removing at least a portion of the catalyst metal with a non-aqueous media. 
     
     
         74 . The method of  claim 73  including heating the non-aqueous media used to remove at least a portion of the catalyst metal. 
     
     
         75 . The method of  claim 74  wherein the catalyst metal is cobalt or a cobalt alloy, and non-aqueous media includes at least one from a group consisting essentially of gallium, titanium, molybdenum, indium, iron, tin, zirconium, sodium, potassium, and mercury.