Methods for fabricating polycrystalline diamond compacts using at least one preformed transition layer and resultant polycrystalline diamond compacts

Abstract

Embodiments relate to polycrystalline diamond compacts (“PDCs”) that are less susceptible to liquid metal embrittlement damage due to the use of at least one transition layer between a polycrystalline diamond (“PCD”) layer and a substrate. In an embodiment, a PDC includes a PCD layer, a cemented carbide substrate, and at least one transition layer bonded to the substrate and the PCD layer. The at least one transition layer is formulated with a coefficient of thermal expansion (“CTE”) that is less than a CTE of the substrate and greater than a CTE of the PCD layer. At least a portion of the PCD layer includes diamond grains defining interstitial regions and a metal-solvent catalyst occupying at least a portion of the interstitial regions. The diamond grains and the catalyst collectively exhibit a coercivity of about 115 Oersteds or more and a specific magnetic saturation of about 15 Gauss·cm 3 /grams or less.

1 . A method for manufacturing a polycrystalline diamond compact, comprising:
 forming an assembly including at least one preformed transition layer disposed between a preformed polycrystalline diamond body and a substrate;   wherein the at least one preformed transition layer includes a plurality of diamond grains and at least one additive;   wherein the at least one preformed transition layer exhibits a coefficient of thermal expansion (“CTE”) that is less than a CTE of the substrate and greater than a CTE of the preformed polycrystalline diamond body; and   subjecting the assembly to a high-temperature/high-pressure process to effective to bond the preformed polycrystalline diamond body to the at least one preformed transition layer.   
     
     
         2 . The method of  claim 1  wherein the at least one additive includes at least one member selected from the group consisting of tungsten carbide, chromium carbide, cemented carbide, and cubic boron nitride. 
     
     
         3 . The method of  claim 1  wherein the at least one additive is about 25 volume % to about 50 volume % of the at least one preformed transition layer. 
     
     
         4 . The method of  claim 1  wherein the preformed polycrystalline diamond body is substantially free of the at least one additive. 
     
     
         5 . The method of  claim 1  wherein at least some of the plurality of diamond grains of the at least one preformed transition layer exhibit diamond-to-diamond bonding therebetween. 
     
     
         6 . The method of  claim 1  wherein the plurality of diamond grains of the at least one preformed transition layer exhibit substantially no diamond-to-diamond bonding therebetween. 
     
     
         7 . The method of  claim 1  wherein the preformed polycrystalline diamond body is at least partially leached. 
     
     
         8 . The method of  claim 7  wherein, prior to being at least partially leached, the preformed polycrystalline diamond body exhibits a coercivity of about 115 Oersteds (“Oe”) or more and a specific magnetic saturation of about 15 Gauss·cm 3 /grams (“G·cm3/g”) or less. 
     
     
         9 . The method of  claim 8  wherein the coercivity is about 130 Oe to about 160 Oe and the specific magnetic saturation is about 10 G·cm 3 /g to about 15 G·cm 3 /g. 
     
     
         10 . The method of  claim 1 , further comprising at least partially leaching the preformed polycrystalline diamond body prior to forming the assembly. 
     
     
         11 . The method of  claim 1  wherein the at least one preformed transition layer includes a plurality of preformed transition layers. 
     
     
         12 . A method for manufacturing a polycrystalline diamond compact, comprising:
 forming a polycrystalline diamond body;   at least partially leaching the polycrystalline diamond body to form an at least partially leached polycrystalline diamond body;   separately forming at least one transition layer from the polycrystalline diamond body, the at least one transition layer formed at least partially from a mixture including a plurality of diamond particles and at least one additive selected from the group consisting of carbide particles, cemented carbide particles, and cubic boron nitride; and   bonding the at least one transition layer to a carbide substrate and the at least partially leached polycrystalline diamond body to form the polycrystalline diamond compact.   
     
     
         13 . The method of  claim 12  wherein the polycrystalline diamond body exhibits a coercivity of about 115 Oersteds (“Oe”) or more and a specific magnetic saturation of about 15 Gauss·cm 3 /grams (“G·cm3/g”) or less. 
     
     
         14 . The method of  claim 13  wherein the coercivity is about 130 Oe to about 160 Oe, and the specific magnetic saturation is about 10 G·cm 3 /g to about 15 G·cm 3 /g. 
     
     
         15 . The method of  claim 12  wherein the at least one transition layer is bonded to the carbide substrate prior to bonding the at least partially leached polycrystalline diamond body to the at least one transition layer. 
     
     
         16 . The method of  claim 12  wherein the at least one transition layer is bonded to the carbide substrate after bonding the at least partially leached polycrystalline diamond body to the at least one transition layer. 
     
     
         17 . The method of  claim 12  wherein the at least one additive includes about 25 volume % to about 50 volume % of the mixture. 
     
     
         18 . The method of  claim 12  wherein separately forming at least one transition layer from the polycrystalline diamond body includes separately forming the at least one transition layer in a high-temperature/high-pressure process. 
     
     
         19 . The method of  claim 12 , further comprising:
 wherein bonding the at least one transition layer to a carbide substrate and the at least partially leached polycrystalline diamond body to form the polycrystalline diamond compact includes infiltrating the at least partially leached polycrystalline diamond body with a metallic infiltrant; and   at least partially leaching the metallic infiltrant from the infiltrated polycrystalline diamond body.   
     
     
         20 . A method for manufacturing a polycrystalline diamond compact, comprising:
 forming at least one transition layer at least partially from a mixture including a plurality of diamond particles and at least one additive in a high-pressure/high-temperature process, wherein the at least one additive includes at least one member selected from the group consisting of carbide particles, cemented carbide particles, and cubic boron nitride;   separately forming a polycrystalline diamond body from the at least one transition layer in a high-pressure/high-temperature process;   at least partially leaching the polycrystalline diamond body to form an at least partially leached polycrystalline diamond body; and   bonding the at least one transition layer to a carbide substrate and the at least partially leached polycrystalline diamond body in a high-pressure/high-temperature process.   
     
     
         21 . The method of  claim 20  wherein the at least one transition layer is bonded to the carbide substrate prior to bonding the at least partially leached polycrystalline diamond body to the at least one transition layer. 
     
     
         22 . The method of  claim 20  wherein the at least one transition layer is bonded to the carbide substrate after bonding the at least partially leached polycrystalline diamond body to the at least one transition layer. 
     
     
         23 . The method of  claim 20 , further comprising:
 wherein bonding the at least one transition layer to a carbide substrate and the at least partially leached polycrystalline diamond body in a high-pressure/high-temperature process includes infiltrating the at least partially leached polycrystalline diamond body with a metallic infiltrant; and   at least partially leaching the metallic infiltrant from the infiltrated polycrystalline diamond body.   
     
     
         24 . The method of  claim 20  wherein the at least one transition layer includes a plurality of preformed transition layers. 
     
     
         25 . A polycrystalline diamond compact, comprising:
 an at least partially leached polycrystalline diamond body;   a cemented carbide substrate; and   at least one preformed transition layer disposed between and bonded to the cemented carbide substrate and the at least partially leached polycrystalline diamond body;   wherein the at least one preformed transition layer includes a plurality of diamond grains and at least one additive selected from the group consisting of tungsten carbide, chromium carbide, cemented carbide, and cubic boron nitride.