Methods for manufacturing polycrystalline ultra-hard constructions and polycrystalline ultra-hard constructions

Abstract

Polycrystalline ultra-hard constructions are made by subjecting a sintered ultra-hard body, substantially free of a sintering catalyst material, to a further HPHT process. The process is controlled to initially melt and infiltrating a filler material into the sintered ultra-hard body to form a filler region having interstitial regions filled with the filler material. The filler region extends a partial depth into the sintered ultra-hard body and is formed at a temperature below the melting temperature of an infiltrant material. Next, the process is controlled to melt and infiltrate the infiltrant material into the sintered ultra-hard body to form an infiltrant region that extends a partial depth into the sintered ultra-hard body. A portion of the filler region and/or the infiltrant region may be removed to form a thermally stable region.

What is claimed is: 
     
         1 . A method for making an ultra-hard polycrystalline construction comprising:
 subjecting a sintered ultra-hard body that is substantially free of a catalyst material used to initially sinter the ultra-hard body at high pressure/high temperature conditions to a further high pressure/high temperature process to introduce an infiltrant material, wherein the sintered ultra-hard body comprises a matrix phase of directly bonded together ultra-hard particles, and a plurality of substantially empty interstitial regions disposed within the matrix, wherein the further high pressure/high temperature process comprises:   melting and infiltrating a filler material into the sintered ultra-hard body to form a filler region having interstitial regions filled with the filler material, the filler region extending a partial depth into the sintered ultra-hard body and being formed at a temperature below the melting temperature of an infiltrant material and at a pressure below about 3 GPa; and   melting and infiltrating the infiltrant material into the sintered ultra-hard body to form an infiltrant region, wherein melting and infiltrating the infiltrant material occurs at a temperature and pressure greater than that used to form the filler region, and wherein the infiltrant region extends a partial depth into the sintered ultra-hard body.   
     
     
         2 . The method as recited in  claim 1 , wherein the filler material has a melting temperature of less than about 1,000° C. 
     
     
         3 . The method as recited in  claim 1 , wherein after melting and infiltrating the infiltrant material, the sintered ultra-hard body consists of the filler region and infiltrant region. 
     
     
         4 . The method as recited in  claim 1 , wherein during melting and infiltrating the infiltrant material, a sufficient population of the interstitial regions within the sintered ultra-hard body are filled with either the filler material or the infiltrant material such that the sintered ultra-hard body remains above the Berman/Simon diamond-graphite equilibrium line. 
     
     
         5 . The method as recited in  claim 1 , wherein after melting and infiltrating the infiltrant material less than about 2 percent of the population of the interstitial regions within the sintered ultra-hard body are empty. 
     
     
         6 . The method as recited in  claim 1 , wherein after melting and infiltrating the infiltrant material about 0 to 2 percent of the population of the interstitial regions within the sintered ultra-hard body are empty. 
     
     
         7 . The method as recited in  claim 6 , wherein after melting and infiltrating the infiltrant material about 0 to 1 percent of the population of the interstitial regions within the sintered ultra-hard body are empty. 
     
     
         8 . The method as recited in  claim 6 , wherein after melting and infiltrating the infiltrant material essentially 100 percent of the interstitial regions are filled. 
     
     
         9 . The method as recited in  claim 1 , further comprising attaching a substrate to the ultra-hard body. 
     
     
         10 . The method as recited in  claim 9 , wherein the substrate is attached to the body adjacent the body infiltrant region. 
     
     
         11 . The method as recited in  claim 1 , wherein the filler material is selected from the group consisting of aluminum, gallium, copper, zinc, silver, indium, thallium, tin, lead, bismuth, alloys, metal salts, and mixtures thereof. 
     
     
         12 . The method as recited in  claim 1 , wherein the filler material is selected from the group consisting of metal salts, carbonates, fluorides, chlorides, bromides, sulfides and combinations thereof. 
     
     
         13 . The method as recited in  claim 11 , wherein the filler material is an alloy which is a eutectic alloy. 
     
     
         14 . The method as recited in  claim 1 , wherein the filler material comprises tin or bismuth. 
     
     
         15 . The method as recited in  claim 1 , wherein the melting temperature of the filler material is less than about 700° C. 
     
     
         16 . The method as recited in  claim 1 , wherein the melting temperature of the filler material is less than about 300° C. 
     
     
         17 . The method as recited in  claim 1 , further comprising, after melting and infiltrating the infiltrant material, treating the ultra-hard body to remove the filler material from the filler region to provide a thermally stable region. 
     
     
         18 . The method as recited in  claim 17 , wherein the thermally stable region contains less than about 12 percent by weight filler material, based on the total weight of the ultra-hard body. 
     
     
         19 . The method as recited in  claim 17 , wherein the thermally stable region contains less than about 2 percent by weight filler material, based on the total weight of the ultra-hard body. 
     
     
         20 . The method as recited in  claim 1 , wherein substantially all the ultra-hard particles in the ultra-hard body are directly bonded to one another. 
     
     
         21 . The method as recited in  claim 1 , further comprising placing the filler material adjacent a working surface of the ultra-hard body before melting and introducing the filler material. 
     
     
         22 . The method as recited in  claim 9 , wherein the infiltrant material is provided from the substrate. 
     
     
         23 . The method as recited in  claim 1 , wherein the infiltrant material comprises one or more Group VIII elements of the Periodic table, alloys, and mixtures thereof. 
     
     
         24 . The method as recited in  claim 1 , wherein the infiltrant material and the catalyst material are different. 
     
     
         25 . The method as recited in  claim 24 , wherein the infiltrant material and the catalyst material both comprise cobalt. 
     
     
         26 . The method as recited in  claim 1 , wherein the ultra-hard material is diamond, and the matrix phase is intercrystalline bonded together diamond crystals. 
     
     
         27 . The method as recited in  claim 1 , wherein during melting and infiltrating the infiltrant material, a substrate is used as a source to introduce the infiltrant material, wherein the substrate is different from a substrate used to introduce the catalyst material initially used to sinter the ultra-hard body. 
     
     
         28 . The method as recited in  claim 27 , wherein the substrate used as a source for the infiltrant material has a material makeup that is different from the substrate used to introduce the catalyst material. 
     
     
         29 . The method as recited in  claim 17 , wherein the thermally stable region extends a depth of at least about 0.5 mm from a surface of the ultra-hard body including one or both of a top and side surface. 
     
     
         30 . The method as recited in  claim 17 , further comprising treating the ultra-hard body to remove a portion of the infiltrant material so that the thermally stable region includes a portion of the infiltrant region. 
     
     
         31 . A polycrystalline ultra-hard construction disposed in a high pressure/high temperature device, the construction comprising:
 a sintered ultra-hard body having a material microstructure comprising a matrix phase of directly bonded together ultra-hard particles formed at high pressure/high temperature conditions in the presence of a catalyst material, the ultra-hard body having a surface and including interstitial regions disposed within the matrix phase, wherein the interstitial regions within the ultra-hard body are substantially free of the catalyst material;   wherein the ultra-hard body is at a temperature and pressure sufficient to melt and infiltrate a filler material into the ultra-hard body to form a filler region, wherein the pressure is less than about 3 GPa, the interstitial regions within the filler region comprising the filler material, and wherein the remaining interstitial regions in the ultra-hard body are substantially free of the filler material and the catalyst material; and   an infiltrant material positioned adjacent the ultra-hard body, wherein the infiltrant material is in a solid state at the pressure and temperature.   
     
     
         32 . The construction as recited in  claim 31 , wherein the filler material is selected from the group consisting of aluminum, gallium, zinc, indium, thallium, tin, lead, bismuth, alloys, metal salts, and mixtures thereof, wherein the filler region extends into the ultra-hard body a depth from the surface. 
     
     
         33 . The construction as recited in  claim 31 , wherein the temperature is less than about 700° C. 
     
     
         34 . The construction as recited in  claim 31 , wherein the pressure is less than about 2.5 GPa. 
     
     
         35 . A polycrystalline diamond construction comprising an ultra-hard body having a thermally stable region and an infiltrant region that is formed by the process comprising;
 subjecting a sintered ultra-hard body to a high pressure/high temperature process, the sintered ultra-hard body comprising a matrix phase of intercrystalline bonded together diamond crystals that extends throughout the body, the body including a plurality of interstitial regions disposed within the matrix phase, wherein the interstitial regions are substantially free of a catalyst material that was used to initially form the sintered ultra-hard body, the high pressure/high temperature process comprises;   melting and infiltrating a filler material at a first temperature and first pressure condition to form a filler region in the ultra-hard body, wherein the interstitial regions within the filler region comprise the filler material, the first pressure condition being less than about 3 GPa, the filler region extending into the ultra-hard body a partial depth from an ultra-hard body first surface;   melting and infiltrating an infiltrant material at a second temperature and second pressure condition to form an infiltrant region in the ultra-hard body, wherein the interstitial regions within the infiltrant region comprise the infiltrant material, the second temperature condition being greater than the first temperature condition, and the second pressure condition being greater than the first pressure condition, wherein the ultra-hard body comprising the filler region and the infiltrant region at the second temperature and second pressure condition is in a diamond stable state above the Berman/Simon diamond-graphite equilibrium line; and   treating the ultra-hard body comprising the filler region and infiltrant region to remove the filler material from a population of the interstitial regions within the filler region to form a thermally-stable region that is substantially free of the filler material, and that extends a depth from the ultra-hard body surface.   
     
     
         36 . The construction as recited in  claim 35 , wherein the ultra-hard body comprises the infiltrant region and the thermally stable region, and is substantially free of the filler region. 
     
     
         37 . The construction as recited in  claim 36 , wherein the thermally stable region extends a depth into the infiltrant region, wherein the interstitial regions within the thermally stable region are substantially free of the infiltrant material. 
     
     
         38 . The construction as recited in  claim 35 , wherein the filler material is an alloy which is a eutectic alloy. 
     
     
         39 . The construction as recited in  claim 35 , wherein the filler material comprises tin or bismuth. 
     
     
         40 . The construction as recited in  claim 35 , wherein the melting temperature of the filler material is less than about 700° C. 
     
     
         41 . The construction as recited in  claim 35 , wherein the melting temperature of the filler material less than about 300° C. 
     
     
         42 . The construction as recited in  claim 35 , wherein the infiltrant material comprises one or more Group VIII elements of the Periodic Table, alloys, and mixtures thereof. 
     
     
         43 . The construction as recited in  claim 35 , wherein the infiltrant material and the catalyst material are different. 
     
     
         44 . The construction as recited in  claim 43 , wherein the infiltrant material and the catalyst material both comprise cobalt. 
     
     
         45 . The construction as recited in  claim 35 , wherein the surface comprises a working surface including a top surface and a side surface of the ultra-hard body, and wherein the thermally stable region extends a depth of at least about 0.5 mm from both the top and side surfaces. 
     
     
         46 . The construction as recited in  claim 45 , further comprising a beveled cutting edge interposed between the top and side surfaces, and wherein the thermally stable region extends a depth therefrom. 
     
     
         47 . The construction as recited in  claim 35 , further comprising a substrate attached to the ultra-hard body adjacent the infiltrant region. 
     
     
         48 . The construction as recited in  claim 35 , wherein the ultra-hard body has a thickness of greater than about 1 mm. 
     
     
         49 . A method for making an ultra-hard polycrystalline construction comprising:
 subjecting a plurality of ultra-hard particles to a high pressure/high temperature condition in the presence of a catalyst material to form a polycrystalline ultra-hard material comprising a matrix phase of directly bonded together ultra-hard particles, and a plurality of interstitial regions disposed within the matrix phase which include the catalyst material;   treating the polycrystalline ultra-hard material to remove the catalyst material therefrom to form an ultra-hard body that is substantially free of the catalyst material used to initially form the polycrystalline ultra-hard material;   introducing a filler material, wherein the filler material fills a population of the plurality of interstitial regions of the ultra-hard body in a first region extending a depth from a surface of the ultra-hard body, wherein the first region is formed at a first temperature and at a pressure of less than about 3 GPa;   introducing an infiltrant material into the ultra-hard body comprising the first region at a temperature greater than the first temperature, wherein the infiltrant material fills a population of the plurality of interstitial regions of the ultra-hard body in a second region, wherein the second region is formed while the ultra-hard body is in a diamond stable state above the Berman/Simon diamond-graphite equilibrium line; and   attaching a substrate to the ultra-hard body.   
     
     
         50 . The method of  claim 49 , further, comprising treating the ultra-hard body to remove at least a portion of the filler material therefrom to form a thermally stable region that is substantially free of the filler material. 
     
     
         51 . The method of  claim 50 , further comprising treating the ultra-hard body to remove at least a portion of the infiltrant material therefrom to form the thermally stable region that is substantially free of the infiltrant material. 
     
     
         52 . The method as recited in  claim 49 , wherein the thermally stable region extends a depth of less than about 0.2 mm from the surface. 
     
     
         53 . The method as recited in  claim 49 , wherein the filler material is selected from the group consisting of aluminum, gallium, zinc, indium, thallium, tin, lead, bismuth, carbonates, sulfates, hydroxides, chlorides, alloys, metal salts, and mixtures thereof.