Abrasive compacts

Abstract

The invention is for a polycrystalline diamond abrasive compact comprising a primary polycrystalline diamond material of bonded diamond particles and a secondary polycrystalline diamond material interspersed through the primary polycrystalline diamond material or a region thereof. The invention is characterised in that the secondary polycrystalline diamond material comprises particulates or granules of thermally stable polycrystalline diamond material. The invention extends to an abrasive cutting element suitable for cutting or abrading a substrate or in drilling applications.

1 . A polycrystalline diamond abrasive compact comprising a primary polycrystalline diamond (PCD) material of bonded diamond particles and a secondary PCD material interspersed through the primary PCD material or a region thereof, characterised in that the secondary PCD material comprises particulates or granules of thermally stable polycrystalline diamond (TSPCD) material. 
     
     
         2 . A polycrystalline diamond abrasive compact according to  claim 1 , wherein the particulates or granules of TSPCD are evenly or homogenously dispersed within the primary PCD material or a region thereof. 
     
     
         3 . A polycrystalline diamond abrasive compact according to either one of the preceding claims, wherein the size of the TSPCD particulates or granules is in the range of between 1 and 500 μm. 
     
     
         4 . A polycrystalline diamond abrasive compact according to any one of the preceding claims, wherein the size of the TSPCD particulates or granules is in the range of between 5 and 250 μm. 
     
     
         5 . A polycrystalline diamond abrasive compact according to any one of the preceding claims, wherein the average size of the individual diamond grains within the particulates or granules range from nano-sized up to 50 μm. 
     
     
         6 . A polycrystalline diamond abrasive compact according to any one of the preceding claims, wherein the distribution of grain sizes in the TSPCD particulates or granules is multimodal. 
     
     
         7 . A polycrystalline diamond abrasive compact according to any one of the preceding claims, wherein the mass percent of presintered TSPCD is in the range of between 2% and 50 mass %. 
     
     
         8 . A polycrystalline diamond abrasive compact according to any one of the preceding claims, wherein the mass percent of presintered TSPCD is in the range of between 10% and 40 mass %. 
     
     
         9 . A polycrystalline diamond abrasive compact according to any one of the preceding claims, wherein the TSPCD particulates or granules comprise non-metallic catalyst/solvent sintered PCD, leached PCD, or diamond particles in a sintered ceramic matrix, or a combination thereof. 
     
     
         10 . A polycrystalline diamond abrasive compact according to  claim 9 , wherein the non-metallic catalyst/solvent comprises a carbonate, sulphate or hydroxide salt of an alkali or alkaline earth material. 
     
     
         11 . A polycrystalline diamond abrasive compact according to  claim 9 , wherein the sintered ceramic matrix comprises an oxide, nitride, carbide, or silicon based ceramic, or a combination thereof. 
     
     
         12 . A polycrystalline diamond abrasive compact according to  claim 11 , wherein the silicon based ceramic comprises silicon carbide, silicon nitride, sialon or a material formed by a combination of silicon, carbon, nitrogen, aluminium, titanium and oxygen. 
     
     
         13 . A polycrystalline diamond abrasive compact according to any one of the preceding claims, wherein the average diamond grain size of the primary PCD is 50 μm or less. 
     
     
         14 . A polycrystalline diamond abrasive compact according to any one of the preceding claims, wherein the average diamond grain size of the primary PCD is 25 μm or less. 
     
     
         15 . A polycrystalline diamond abrasive compact according to any one of the preceding claims, wherein the polycrystalline diamond abrasive compact is bonded to a cemented carbide support or substrate. 
     
     
         16 . An abrasive cutting element suitable for cutting or abrading of a substrate or in drilling applications, the abrasive cutting element comprising a polycrystalline diamond abrasive compact according to any one of  claims 1  to  15 .