Diamond drill bit and method of producing a diamond drill bit

Abstract

The diamond drill bit comprises a steel powder comprising iron in a non-zero proportion of up to 99.6% iron and carbon in a proportion between 0.03% and 2.14%, coated diamonds impregnated in the steel powder, and a metallic infiltrant alloy comprising copper and one of tin, silver and both tin and silver; wherein the diamond drill bit is produced by an infiltration process that comprises providing the steel powder to form the matrix; dispersing coated diamonds in the steel powder; compressing the matrix comprising the steel powder and the coated diamond at a cold-compression temperature; after the compressing, adding to the matrix an infiltrant alloy comprising copper and one of tin and silver; and heating the mixture of steel powder, coated diamonds and infiltrant alloy at a fusion temperature allowing the infiltrant alloy to melt, wherein the infiltrant alloy infiltrates the matrix and binds it.

1 . A diamond drill bit comprising a steel powder comprising iron in a non-zero proportion of up to 99.6% and carbon in a proportion between 0.03% and 2.14%, coated diamonds impregnated in said steel powder, and a metallic infiltrant alloy comprising copper and one of tin, silver and both tin and silver; wherein said diamond drill bit is produced by an infiltration process. 
     
     
         2 . A diamond drill bit as defined in  claim 1 , wherein said steel powder further comprises one or more of the following metals: manganese, silicon, phosphorus, sulfur, copper, nickel, chromium, aluminium, titanium, boron, molybdenum and vanadium. 
     
     
         3 . A diamond Drill bit as defined in  claim 1 , wherein said steel powder further comprises tungsten. 
     
     
         4 . A diamond drill bit as defined in  claim 1 , wherein said infiltrant alloy comprises 50-92% copper and 2-50% silver. 
     
     
         5 . A diamond drill bit as defined in  claim 1 , wherein said infiltrant alloy comprises between 75-95% copper and 5-25% tin. 
     
     
         6 . A diamond drill bit as defined in  claim 1 , wherein said infiltrant alloy further comprises zinc. 
     
     
         7 . A diamond drill bit as defined in  claim 1 , wherein said infiltrant alloy further comprises bismuth. 
     
     
         8 . A diamond drill bit as defined in  claim 1 , wherein said steel powder comprises iron particles of a size between 1 and 300 microns. 
     
     
         9 . A method of producing a diamond drill bit as defined in  claim 1  by an infiltration process, comprising:
 providing the steel powder to form a matrix; 
 dispersing the coated diamonds in said steel powder; 
 compressing said matrix comprising said steel powder and said coated diamond at a cold-compression temperature; 
 after the step of compressing said matrix, adding to said matrix an infiltrant alloy comprising copper and one of tin and silver to form a drill bit mixture; and 
 heating the drill bit mixture at or above a fusion temperature of said infiltrant alloy, for allowing said infiltrant alloy to melt, wherein said infiltrant alloy infiltrates said matrix and binds it. 
 
     
     
         10 . The method as defined in  claim 9 , wherein said infiltrant alloy comprises 50-92% copper and 2-50% silver. 
     
     
         11 . The method as defined in  claim 9 , wherein said infiltrant alloy comprises between 75-95% copper and 5-25% tin. 
     
     
         12 . The method as defined in  claim 9 , wherein the step of providing the steel powder comprises providing a ferrous-based powder and graphite that comprises carbon, and wherein before the step of heating the mixture at or above a fusion temperature of said infiltrant alloy, said method further comprising the step of heating said drill bit mixture at or above a diffusion temperature of the carbon in the iron but below the fusion temperature of said infiltrant alloy for allowing the carbon to migrate into said iron. 
     
     
         13 . The method as defined in  claim 1 , wherein said steel powder further comprises one or more of the following metals: manganese, silicon, phosphorus, sulfur, copper, nickel, chromium, aluminium, titanium, boron, molybdenum and vanadium. 
     
     
         14 . The method as defined in  claim 1 , wherein said steel powder further comprises tungsten.