Thermally stable diamond bonded materials and compacts

Abstract

Thermally stable diamond bonded construction comprise a diamond bonded body including a thermally stable region, comprising a plurality of diamond grains bonded together by a reaction product of the diamond grains with a reactant such as Si, and a polycrystalline diamond region, comprising intercrystalline bonded diamond and a catalyst material. The body further comprises a ceramic compound formed by reaction of an Nb, Zr, Ti, or Mo getter material with a gaseous element generated during HPHT sintering of the diamond bonded body. The diamond bonded body may comprise from 0.1 to 15 percent by weight of the ceramic compound. The diamond bonded body can be formed during a single HPHT process operated at different temperatures when the reactant has a melting temperature above the catalyst material. The construction may include a metallic substrate attached to the diamond bonded body to facilitate use as a wear or cutting element.

What is claimed: 
     
         1 . A method for forming a thermally stable diamond bonded construction comprising subjecting a volume of diamond grains to a high pressure-high temperature condition in the presence of a getter material and a reactant to form a sintered diamond bonded body having a thermally stable region, wherein the getter material reacts with gaseous elements formed during the high pressure-high temperature condition to form a ceramic compound disposed within the diamond bonded body, and wherein the reactant reacts with the diamond grains and forms bonds therebetween to form the thermally stable region. 
     
     
         2 . The method as recited in  claim 1  wherein the getter material comprises in the range of from about 0.1 to 10 percent by weight of the total weight of the materials used to form the diamond bonded body. 
     
     
         3 . The method as recited in  claim 1  wherein the ceramic compound comprises in the range of from about 0.1 to 15 percent by weight of the total weight of the diamond bonded body. 
     
     
         4 . The method as recited in  claim 1  wherein, during the step of subjecting, a portion of the diamond volume is subjected to the high pressure-high temperature condition in the presence of a metal solvent catalyst and does not include the reactant to form a polycrystalline diamond region that is adjacent the thermally stable region. 
     
     
         5 . The method as recited in  claim 4  wherein, during the step of subjecting, the high pressure-high temperature condition is operated at a first temperature to form the thermally stable region, and then at a second temperature to form the polycrystalline diamond region, wherein the first temperature is less than the second temperature. 
     
     
         6 . The method as recited in  claim 4  wherein the thermally stable region is substantially free of the metal solvent catalyst. 
     
     
         7 . The method as recited in  claim 1  wherein the getter material is selected from the group of materials consisting of Nb, Zr, Ti, Mo, and combinations thereof. 
     
     
         8 . The method as recited in  claim 1  wherein, during the step of subjecting, the diamond bonded body is formed adjacent a metallic substrate and is attached thereto during the high pressure-high temperature condition. 
     
     
         9 . The method as recited in  claim 1  wherein during the step of subjecting, the reactant is silicon that reacts with the diamond grains to form SiC that bonds the diamond grains together, wherein the volume content of SiC is less than about 20 percent. 
     
     
         10 . A method for forming a thermally stable diamond constructions comprising:
 combining a volume of diamond grains together with silicon and a getter material to form a mixture;   subjecting the mixture to a high pressure-high temperature condition to form a diamond bonded body comprising a thermally stable region and a polycrystalline diamond region adjacent the thermally stable region, wherein the thermally stable region comprises diamond grains bonded together by a reaction product of the diamond grain and the silicon, wherein the polycrystalline diamond region comprises intercrystalline bonded together diamond grains and a metal catalyst disposed within interstitial regions, and wherein the diamond bonded body comprises a ceramic compound formed from the getter material.   
     
     
         11 . The method as recited in  claim 10  wherein, during the step of subjecting, the diamond bonded body is formed in the presence of the metal catalyst. 
     
     
         12 . The method as recited in  claim 10  wherein, during the step of subjection, the mixture is disposed adjacent a metallic substrate and is bonded thereto during the high-pressure-high temperature condition. 
     
     
         13 . The method as recited in  claim 10  wherein the getter material is selected is selected from the group of materials consisting of Nb, Zr, Ti, Mo, and combinations thereof. 
     
     
         14 . The method as recited in  claim 13  wherein the ceramic compound is selected from the group consisting of oxides, nitrides and hydrides of the getter material. 
     
     
         15 . The method as recited in  claim 10  wherein the polycrystalline diamond region comprises the reaction product. 
     
     
         16 . The method as recited in  claim 10  wherein, during the step of subjecting, the mixture is subjected to a first temperature that is at or above the temperature of silicon, and then is subjected to a higher second temperature that is at or above the temperature of the metal catalyst. 
     
     
         20 . A method for forming a cutting element comprising a thermally stable diamond bonded construction comprising:
 combining diamond grains with silicon and a getter material to form an assembly; and   subjecting the assembly to high pressure-high temperature condition to form a sintered diamond bonded body comprising a thermally stable region and a polycrystalline diamond region adjacent the thermally stable region, the assembly being positioned adjacent a metallic substrate, the thermally stable region being formed at a first temperature condition by reaction of the silicon with diamond grains to bond the diamond grains together, the polycrystalline diamond region being formed at a second temperature condition in the presence of a catalyst metal, wherein the second temperature condition is greater than the first temperature condition, the diamond bonded body comprising a ceramic compound formed by reaction of the getter material, and wherein the diamond bonded body is joined together with the substrate during the high pressure-high temperature condition.