Earth-boring bits

Abstract

The present invention relates to compositions and methods for forming a bit body for an earth-boring bit. The bit body may comprise hard particles, wherein the hard particles comprise at least one carbide, nitride, boride, and oxide and solid solutions thereof, and a binder binding together the hard particles. The binder may comprise at least one metal selected from cobalt, nickel, and iron, and at least one melting point reducing constituent selected from a transition metal carbide in the range of 30 to 60 weight percent, boron up to 10 weight percent, silicon up to 20 weight percent, chromium up to 20 weight percent, and manganese up to 25 weight percent, wherein the weight percentages are based on the total weight of the binder. In addition, the hard particles may comprise at least one of (i) cast carbide (WC+W2C) particles, (ii) transition metal carbide particles selected from the carbides of titanium, chromium, vanadium, zirconium, hafnium, tantalum, molybdenum, niobium, and tungsten, and (iii) sintered cemented carbide particles.

1 . A composition for forming a bit body for an earth-boring bit, the composition comprising: 
 hard particles comprising at least one of a carbide, a nitride, a boride, a silicide, an oxide, and solid solutions thereof; and    a binder, wherein the binder comprises: 
 at least one metal selected from cobalt, nickel, and iron; and  
 at least one melting point reducing constituent selected from at least one of a transition metal carbide, boride, or silicide up to 60 weight percent, a transition metal up to 50 weight percent, boron up to 10 weight percent, silicon up to 20 weight percent, chromium up to 20 weight percent, and manganese up to 25 weight percent, wherein the weight percentages are based on the total weight of the binder.  
   
     
     
         2 . The composition of  claim 1 , wherein the melting point reducing constituent is at least one of tungsten carbide present from 30 to 60 weight percent, tungsten present from 30 to 55 weight percent, carbon present from 1.5 to 4 weight percent, boron present from 1 to 10 weight percent, silicon present from 2 to 20 weight percent, chromium present from 2 to 20 weight percent, and manganese present from 10 to 25 weight percent.  
     
     
         3 . The composition of  claim 1 , wherein the hard particles are at least one of individual single crystals, as polycrystalline particles, as solid solutions, as polycrystalline particles comprising two or more phases, and sintered granules comprising a binder, sintered granules without a binder.  
     
     
         4 . The composition of  claim 1 , wherein the hard particles comprise at least one transition metal carbide selected from titanium carbide, chromium carbide, vanadium carbide, zirconium carbide, hafnium carbide, tantalum carbide, molybdenum carbide, niobium carbide, and tungsten carbide.  
     
     
         5 . The composition of  claim 1 , wherein the melting point reducing constituent is at least one of tungsten carbide, boride, and silicide in the range of 30 to 60 weight percent based on the total weight of the binder.  
     
     
         6 . The composition of  claim 1 , wherein the binder comprises 40 to 50 weight percent of tungsten carbide and 40 to 60 weight percent of at least one or iron, cobalt, and nickel, all based on the total weight of the binder.  
     
     
         7 . The composition of  claim 6 , wherein the binder comprises 40 to 50 weight percent of tungsten carbide and 40 to 60 weight percent of cobalt, all based on the total weight of the binder.  
     
     
         8 . The composition of  claim 7 , wherein the binder further comprises up to 10 weight percent of at least one of boron and silicon based on the total weight of the binder.  
     
     
         9 . The composition of  claim 1 , wherein the melting point reducing constituent is silicon in the range of 2 to 20 weight percent based on the total weight of the binder.  
     
     
         10 . The composition of  claim 6 , wherein the binder comprises 40 to 50 weight percent of tungsten carbide and 40 to 60 weight percent of nickel, all based on the total weight of the binder.  
     
     
         11 . The composition of  claim 10 , wherein the binder further comprises up to 10 weight percent of boron based on the total weight of the binder.  
     
     
         12 . The composition of  claim 1 , wherein the binder comprises at least 80 weight percent of at least of one of nickel, iron, and cobalt based on the total weight of the binder.  
     
     
         13 . The composition of  claim 12 , wherein the binder further comprises up to 20 weight percent of silicon based on the total weight of the binder.  
     
     
         14 . The composition of  claim 12 , wherein the binder further comprises up to 10 weight percent of boron based on the total weight of the binder.  
     
     
         15 . The composition of  claim 1 , wherein the binder comprises from 90 to 99 weight percent of nickel and 1 to 10 weight percent of boron, all based on the total weight of the binder.  
     
     
         16 . The composition of  claim 1 , wherein the binder comprises from 90 to 99 weight percent of cobalt and 1 to 10 weight percent of boron, all based on the total weight of the binder.  
     
     
         17 . The composition of  claim 1 , wherein the binder comprises up to 60 weight percent of the melting point reducing constituent based on the total weight of the binder.  
     
     
         18 . The composition of  claim 17 , wherein the melting point reducing constituent is at least one of a tungsten carbide, chromium, boron, carbon, and silicon.  
     
     
         19 . The composition of  claim 17 , wherein the melting point reducing constituent is one of tungsten carbide, boron, and silicon.  
     
     
         20 . A composition for forming a bit body for an earth-boring bit, comprising: 
 hard particles comprising at least one of a carbide, a nitride, a boride, a silicide; an oxide, and solid solutions thereof; and    a binder, wherein the binder has a melting point in the range of 1050° C. to 1350° C.    
     
     
         21 . The composition of  claim 20 , wherein the hard particles are present as individual single crystals, as polycrystalline particles, as solid solutions, as polycrystalline particles comprising two or more phases, or sintered granules (with or without the aid of a binding agent.  
     
     
         22 . The composition of  claim 20 , wherein the carbide is at least one transition metal carbide selected from titanium carbide, chromium carbide, vanadium carbide, zirconium carbide, hafnium carbide, tantalum carbide, molybdenum carbide, niobium carbide, and tungsten carbide.  
     
     
         23 . The composition of  claim 22 , wherein the transition metal carbide of the hard particles is tungsten carbide.  
     
     
         24 . The composition of  claim 20 , wherein the binder is an alloy comprising at least one of iron, cobalt and nickel.  
     
     
         25 . The composition of  claim 23 , wherein the binder further comprises at least one transition metal carbide selected from titanium carbide, tantalum carbide, niobium carbide, chromium carbide, molybdenum carbide, boron carbide, carbon carbide, silicon carbide, and ruthenium carbide.  
     
     
         26 . The composition of  claim 20 , wherein the binder comprises at least one of silicon, a transition metal carbide, and boron.  
     
     
         27 . The composition of  claim 20 , wherein the concentration of transition metal carbide in the composition is in the range of 30% to 99% by volume.  
     
     
         28 . The composition of  claim 20 , wherein the concentration of transition metal carbide in the composition is in the range of 45% to 85% by volume.  
     
     
         29 . The composition of  claim 19 , further comprising: 
 at least one cemented carbide insert.    
     
     
         30 . The composition of  claim 29 , wherein the cemented carbide insert includes at least one cutter pocket.  
     
     
         31 . The composition of  claim 20 , wherein the hard particles comprise at least one of macrocrystalline tungsten carbide, eutectic tungsten carbide, sintered transition metal carbide, crushed sintered metal carbide.  
     
     
         32 . The composition of  claim 31 , wherein the hard particles are one or more of irregularly shaped, prolate, oblate, and spherical.  
     
     
         33 . A composition for forming a matrix body, comprising: 
 hard particles of a transition metal carbide; and    a binder comprising at least one of nickel, iron, and cobalt and having a melting point less than 1350° C.    
     
     
         34 . The composition of  claim 33 , wherein the transition metal carbide is at least one transition metal selected from titanium carbide, chromium carbide, vanadium carbide, zirconium carbide, hafnium carbide, tantalum carbide, molybdenum carbide, niobium carbide, and tungsten carbide.  
     
     
         35 . The composition of  claim 34 , wherein the transition metal carbide is tungsten carbide.  
     
     
         36 . The composition of  claim 33 , wherein the binder is an alloy comprising at least one of iron, cobalt, and nickel.  
     
     
         37 . The composition of  claim 36 , wherein the binder further comprises at least one of a transition metal carbide, tungsten, carbon, boron, silicon, chromium, manganese, silver, aluminum, copper, tin, and zinc in a concentration that reduces the melting point of the at least one of nickel, iron, and cobalt.  
     
     
         38 . The composition of  claim 37 , wherein the binder comprises at least one of tungsten, carbide, boron, silicon, chromium, and manganese.  
     
     
         39 . A method of forming an article selected from a bit body, a roller cone, and a conical holder, the method comprising: 
 infiltrating a mass of hard particles comprising at least one transition metal carbide with a binder having a melting point in the range of 1050° C. to 1350° C.    
     
     
         40 . The method of  claim 39 , wherein the binder comprises at least one of iron, nickel, and cobalt in a total concentration of from 40 to 99 weight percent based on the total weight of the binder.  
     
     
         41 . The method of  claim 40 , wherein the binder further comprises at least one of a transition metal carbide, tungsten, carbon, boron, silicon, chromium, manganese, silver, aluminum, copper, tin, and zinc.  
     
     
         42 . The method of  claim 40 , wherein the binder comprises at least one of tungsten carbide, boron, silicon, chromium, and manganese.  
     
     
         43 . The method of  claim 39 , wherein the transition metal carbide of the hard particles is at least one carbide selected from titanium carbide, chromium carbide, vanadium carbide, zirconium carbide, hafnium carbide, tantalum carbide, molybdenum carbide, niobium carbide, and tungsten carbide.  
     
     
         44 . The method of  claim 43 , wherein the binder is a near eutectic compositions.  
     
     
         45 . The method of  claim 44 , wherein the binder has a concentration of at least one of iron, nickel, and cobalt within 10 weight percent of the eutectic concentration.  
     
     
         46 . A method of forming an article, comprising: 
 infiltrating a mass of hard particles comprising at least one transition metal carbide with a binder comprising at least one of nickel, iron, and cobalt and having a melting point less than 1350° C.    
     
     
         47 . The method of  claim 46 , wherein the total concentration of iron, nickel, and cobalt in the binder is greater than 10 weight percent by total weight of the binder.  
     
     
         48 . The method of  claim 46 , wherein the transition metal carbide of the hard particles is at least one of titanium carbide, chromium carbide, vanadium carbide, zirconium carbide, hafnium carbide, tantalum carbide, molybdenum carbide, niobium carbide, and tungsten carbide.  
     
     
         49 . The method of  claim 46 , wherein the binder further comprises at least one of a transition metal carbide, tungsten, carbon, boron, silicon, chromium, manganese, silver, aluminum, copper, tin, and zinc.  
     
     
         50 . The method of  claim 49 , wherein the binder comprises at least one of tungsten, carbide, boron, silicon, chromium, and manganese.  
     
     
         51 . A method of producing an earth-boring bit body the method comprising: 
 casting the earth-boring bit body from a molten mixture comprising at least one of iron, nickel, and cobalt and a carbide of a transition metal.    
     
     
         52 . The method of  claim 51 , wherein the mixture is a near eutectic mixture.  
     
     
         53 . The method of  claim 51 , wherein the total concentration of nickel, iron, and cobalt, and the concentration of transition metal carbide are within 10% of the eutectic concentrations.  
     
     
         54 . The method of  claim 51 , wherein the mixture further comprises at least one of transition metal carbide, tungsten, carbon, boron, silicon, chromium, manganese, silver, aluminum, copper, tin, and zinc.  
     
     
         55 . The method of  claim 54 , wherein the mixture comprises at least one of tungsten carbide, boron, silicon, chromium, and manganese.  
     
     
         56 . An earth-boring bit body, comprising: 
 tungsten carbide, wherein the tungsten carbide is greater than 75 volume % of the bit body.    
     
     
         57 . The earth-boring bit body of  claim 56 , further comprising a binder binding together the tungsten carbide.  
     
     
         58 . The earth-boring bit body of  claim 57 , wherein the binder comprises at least one of cobalt, iron, and nickel.  
     
     
         59 . The earth-boring bit body of  claim 58 , wherein the binder comprises at least 80 weight percent of at least of one of nickel, iron, and cobalt based on the total weight of the binder.  
     
     
         60 . The earth-boring bit body of  claim 59 , wherein the binder further comprises up to 20 weight percent of silicon based on the total weight of the binder.  
     
     
         61 . The earth-boring bit body of  claim 59 , wherein the binder further comprises up to 10 weight percent of boron based on the total weight of the binder.  
     
     
         62 . The earth-boring bit body of  claim 59 , wherein the binder comprises 90 to 99 weight percent of nickel and 1 to 10 weight percent of boron based on the total weight of the binder.  
     
     
         63 . The earth-boring bit body of  claim 59 , wherein the binder comprises 90 to 99 weight percent of cobalt and 1 to 10 weight percent of boron, each based on the total weight of the binder.  
     
     
         64 . The earth-boring bit body of  claim 58 , wherein the binder further comprises at least one of a transition metal carbide, tungsten, carbon, boron, silicon, chromium, manganese, silver, aluminum, copper, tin, and zinc.  
     
     
         65 . The earth-boring bit body of  claim 58 , wherein the binder further comprises at least one of tungsten carbide, tungsten, carbon, boron, silicon, chromium, and manganese.