Sintered polycrystalline diamond material with extremely fine microstructures

Abstract

A sintered polycrystalline diamond material (PCD) of extremely fine grain size is manufactured by sintering a diamond powder with pre-blended catalyst metal under high pressure/high temperature (HP/HT) processing. The PCD material has an average sintered diamond grain structure of less than 1.0 μm.

1 . A polycrystalline diamond (PCD) body comprising diamond crystals having an arithmetic mean, as-sintered, diamond grain size less than 1 μm.  
   
   
       2 . The PCD body of  claim 1  wherein the grain size is greater than 0.1 μm.  
   
   
       3 . The PCD body of  claim 1  wherein the body has an oxygen content below about 0.05 weight-percent.  
   
   
       4 . The PCD body of  claim 1  wherein the body has a nitrogen content below about 0.01 weight-percent.  
   
   
       5 . The polycrystalline diamond (PCD) body of  claim 1  comprising diamond crystals, wherein at least 63% of the crystals have a grain size that is less than 1.0 μm.  
   
   
       6 . The polycrystalline diamond (PCD) body of  claim 1 , wherein the thickness of the sintered diamond body is greater than about 0.5 mm.  
   
   
       7 . The PCD body of  claim 1  further comprising a cemented metal carbide support.  
   
   
       8 . A method for producing a polycrystalline diamond (PCD) body with an arithmetic mean as-sintered grain size less than 1 μm, comprising: 
 providing diamond particles having a volumetric mean particle size of less than about 1.0 μm and greater than about 0.1 μm;    blending, with the diamond particles, a catalyst metal having an average particle size that is less than that of the diamond grain size, to form a diamond powder blend; and    processing the diamond powder blend using a pressure and a temperature for a time sufficient to cause intercrystalline bonding between adjacent diamond grains.    
   
   
       9 . The method of  claim 8  wherein the catalyst metal comprises an iron group metal.  
   
   
       10 . The method of  claim 8  wherein the metal catalyst comprises cobalt.  
   
   
       11 . The method of  claim 8  wherein the metal catalyst comprises about 0.5% to about 15% by weight of the diamond powder blend.  
   
   
       12 . The method of  claim 8  wherein the metal catalyst comprises nanocrystalline particles.  
   
   
       13 . The method of  claim 12  wherein the nanocrystalline particles are directly adhered to the diamond particles.  
   
   
       14 . The method of  claim 8  wherein the pressure is between about 20 Kbar and 70 Kbar, and wherein the temperature is at least about 1000° C., and wherein the time is between about 3 minutes to about 120 minutes.  
   
   
       15 . The method of  claim 8  further comprising processing the diamond powder blend together with a cemented metal carbide support.  
   
   
       16 . The method of  claim 8  wherein the metal carbide support comprises a support annulus and the diamond power blend is disposed within the support annulus.  
   
   
       17 . A polycrystalline diamond (PCD) wear component comprising a PCD body comprising diamond crystals having an arithmetic mean, as-sintered, diamond grain size between about 0.1 μm and about 1.0 μm.  
   
   
       18 . The component of  claim 17  wherein the PCD body is monolithic.  
   
   
       19 . The component of  claim 17  wherein the PCD body is bonded to a substrate.  
   
   
       20 . The component of  claim 17  wherein the substrate comprises a cemented metal carbide.  
   
   
       21 . The component of  claim 17  wherein the cemented metal carbide comprises cemented tungsten carbide.