Earth-boring tools and cutter assemblies having a cutting element co-sintered with a cone structure, methods of using the same

Abstract

Methods of forming cutter assemblies for use on earth-boring tools include sintering a cone structure to fuse one or more cutting elements thereto. In some embodiments, one or more green, brown, or fully sintered cutting elements may be positioned on a green or brown cone structure prior to sintering the cone structure to a final density. Cutter assemblies may be formed by such methods, and such cutter assemblies may be used in earth-boring tools such as, for example, earth-boring rotary drill bits and hole openers.

1 . A method of forming a cutter assembly for use on an earth-boring tool, the method comprising:
 providing a less than fully sintered cone structure comprising hard particles and a matrix material;   positioning at least one cutting element on the less than fully sintered cone structure; and   sintering the cone structure to a final density to fuse the at least one cutting element to the cone structure.   
   
   
       2 . The method of  claim 1 , wherein providing a less than fully sintered cone structure comprises providing a green cone structure. 
   
   
       3 . The method of  claim 2 , wherein providing a green cone structure comprises:
 mixing the hard particles with particles comprising the matrix material to form a powder mixture; and   pressing the powder mixture to form the green cone structure.   
   
   
       4 . The method of  claim 3 , further comprising:
 selecting the hard particles from the group consisting of diamond, boron carbide, boron nitride, aluminum nitride, and carbides or borides of the group consisting of W, Ti, Mo, Nb, V, Hf, Ta, Cr, Zr, Al, and Si; and   selecting the matrix material from the group consisting of cobalt-based alloys, iron-based alloys, nickel-based alloys, cobalt and nickel-based alloys, iron and nickel-based alloys, iron and cobalt-based alloys, aluminum-based alloys, copper-based alloys, magnesium-based alloys, and titanium-based alloys.   
   
   
       5 . The method of  claim 2 , further comprising machining at least one aperture in the green cone structure, and wherein positioning at least one cutting element on the less than fully sintered cone structure comprises inserting the at least one cutting element into the at least one aperture of the green cone structure. 
   
   
       6 . The method of  claim 5 , further comprising providing an average clearance of between about 0.001 inch and about 0.025 inch between exterior surfaces of the at least one cutting element and the surfaces of the green cone structure within the at least one aperture. 
   
   
       7 . The method of  claim 2 , further comprising machining at least one protrusion on the green cone structure, and wherein positioning at least one cutting element on the less than fully sintered cone structure comprises placing the at least one cutting element onto the at least one protrusion of the green cone structure. 
   
   
       8 . The method of  claim 2 , wherein positioning at least one cutting element on the less than fully sintered cone structure comprises positioning at least one green cutting element on the green cone structure, and wherein sintering the cone structure comprises sintering the green cone structure with the green cutting element thereon to a final density. 
   
   
       9 . The method of  claim 2 , wherein positioning at least one cutting element on the less than fully sintered cone structure comprises positioning at least one brown cutting element on the green cone structure, and wherein sintering the cone structure comprises sintering the green cone structure with the brown cutting element thereon to a final density. 
   
   
       10 . The method of  claim 1 , wherein providing a less than fully sintered cone structure comprises providing a brown cone structure. 
   
   
       11 . The method of  claim 10 , wherein providing a brown cone structure comprises:
 mixing the hard particles with particles comprising the matrix material to form a powder mixture;   pressing the powder mixture to form a green cone structure; and   partially sintering the green cone structure to form the brown cone structure.   
   
   
       12 . The method of  claim 11 , further comprising:
 selecting the hard particles from the group consisting of diamond, boron carbide, boron nitride, aluminum nitride, and carbides or borides of the group consisting of W, Ti, Mo, Nb, V, Hf, Ta, Cr, Zr, Al, and Si; and   selecting the matrix material from the group consisting of cobalt-based alloys, iron-based alloys, nickel-based alloys, cobalt and nickel-based alloys, iron and nickel-based alloys, iron and cobalt-based alloys, aluminum-based alloys, copper-based alloys, magnesium-based alloys, and titanium-based alloys.   
   
   
       13 . The method of  claim 10 , further comprising machining at least one aperture in the brown cone structure, and wherein positioning at least one cutting element on the less than fully sintered cone structure comprises inserting the at least one cutting element into the at least one aperture of the brown cone structure. 
   
   
       14 . The method of  claim 10 , further comprising machining at least one protrusion on the brown cone structure, and wherein positioning at least one cutting element on the less than fully sintered cone structure comprises placing the at least one cutting element onto the at least one protrusion of the brown cone structure. 
   
   
       15 . The method of  claim 10 , wherein positioning at least one cutting element on the less than fully sintered cone structure comprises positioning at least one green cutting element on the brown cone structure, and wherein sintering the cone structure comprises sintering the brown cone structure with the green cutting element thereon to a final density. 
   
   
       16 . The method of  claim 10 , wherein positioning at least one cutting element on the less than fully sintered cone structure comprises positioning at least one brown cutting element on the brown cone structure, and wherein sintering the cone structure comprises sintering the brown cone structure with the brown cutting element thereon to a final density. 
   
   
       17 . The method of  claim 1 , wherein positioning at least one cutting element on the less than fully sintered cone structure comprises positioning at least one cutting element comprising hard particles and a matrix material on the less than fully sintered cone structure. 
   
   
       18 . The method of  claim 17 , further comprising:
 selecting the hard particles of the at least one cutting element from the group consisting of diamond, boron carbide, boron nitride, aluminum nitride, and carbides or borides of the group consisting of W, Ti, Mo, Nb, V, Hf, Ta, Cr, Zr, Al, and Si; and   selecting the matrix material of the at least one cutting element from the group consisting of cobalt-based alloys, iron-based alloys, nickel-based alloys, cobalt and nickel-based alloys, iron and nickel-based alloys, iron and cobalt-based alloys, aluminum-based alloys, copper-based alloys, magnesium-based alloys, and titanium-based alloys.   
   
   
       19 . The method of  claim 1 , wherein positioning at least one cutting element on the less than fully sintered cone structure further comprises causing the at least one cutting element to have a varying material composition between a first region proximate an interface between the at least one cutting element and the less than fully sintered cone and a second region proximate a formation-engaging surface of the at least one cutting element. 
   
   
       20 . The method of  claim 19 , wherein causing the at least one cutting element to have a varying material composition comprises:
 causing the first region to have a first material composition selected to enhance bonding between the at least one cutting element and the less than fully sintered cone; and   causing the second region to have a second material composition selected to enhance at least one material property of the at least one cutting element.   
   
   
       21 . The method of  claim 1 , further comprising:
 positioning at least one bearing structure on the less than fully sintered cone structure; and   fusing the bearing structure to the less than fully sintered cone structure while sintering the cone structure to a final density.   
   
   
       22 . The method of  claim 1 , further comprising mounting the cone structure on a bearing pin of an earth-boring tool. 
   
   
       23 . An earth-boring tool comprising:
 a bearing pin; and   a cutter assembly rotatably mounted on the bearing pin, the cutter assembly comprising:
 a cone comprising a particle-matrix composite material having a first material composition; and 
 at least one cutting element co-sintered and integral with the cone, the at least one cutting element comprising a particle-matrix composite material having a second material composition differing from the first material composition. 
   
   
   
       24 . The earth-boring tool of  claim 23 , wherein the particle-matrix composite material of the cone comprises a plurality of hard particles dispersed throughout a matrix material, the hard particles comprising a material selected from diamond, boron carbide, boron nitride, aluminum nitride, and carbides or borides of the group consisting of W, Ti, Mo, Nb, V, Hf, Ta, Cr, Zr, Al, and Si, the matrix material selected from the group consisting of cobalt-based alloys, iron-based alloys, nickel-based alloys, cobalt and nickel-based alloys, iron and nickel-based alloys, iron and cobalt-based alloys, aluminum-based alloys, copper-based alloys, magnesium-based alloys, and titanium-based alloys. 
   
   
       25 . The earth-boring tool of  claim 24 , wherein the particle-matrix composite material of the co-sintered cutting element comprises a plurality of hard particles dispersed throughout a matrix material, the hard particles comprising a material selected from diamond, boron carbide, boron nitride, aluminum nitride, and carbides or borides of the group consisting of W, Ti, Mo, Nb, V, Hf, Ta, Cr, Zr, Al, and Si, the matrix material selected from the group consisting of cobalt-based alloys, iron-based alloys, nickel-based alloys, cobalt and nickel-based alloys, iron and nickel-based alloys, iron and cobalt-based alloys, aluminum-based alloys, copper-based alloys, magnesium-based alloys, and titanium-based alloys. 
   
   
       26 . The earth-boring tool of  claim 23 , further comprising at least one bearing structure co-sintered and integral with the cone. 
   
   
       27 . The earth-boring tool of  claim 23 , wherein the at least one bearing structure comprises a particle-matrix composite material. 
   
   
       28 . The earth-boring tool of  claim 23 , wherein the at least one cutting element comprises a cutting insert. 
   
   
       29 . The earth-boring tool of  claim 23 , wherein the at least one cutting element comprises at least a portion of a cutting tooth structure. 
   
   
       30 . The earth-boring tool of  claim 23 , wherein the at least one cutting element has a varying material composition between a first region proximate an interface between the at least one cutting element and the cone and a second region proximate a formation-engaging surface of the at least one cutting element. 
   
   
       31 . A cutter assembly for use on an earth-boring tool, the cutter assembly comprising at least one cutting element co-sintered and integral with a cone structure, the cone structure comprising a particle-matrix composite material having a first material composition, the at least one cutting element comprising a particle-matrix composite material having a second material composition differing from the first material composition. 
   
   
       32 . The cutter assembly of  claim 31 , wherein the particle-matrix composite material of the cone structure comprises a plurality of hard particles dispersed throughout a matrix material, the hard particles comprising a material selected from diamond, boron carbide, boron nitride, aluminum nitride, and carbides or borides of the group consisting of W,. Ti, Mo, Nb, V, Hf, Ta, Cr, Zr, Al, and Si, the matrix material selected from the group consisting of cobalt-based alloys, iron-based alloys, nickel-based alloys, cobalt and nickel-based alloys, iron and nickel-based alloys, iron and cobalt-based alloys, aluminum-based alloys, copper-based alloys, magnesium-based alloys, and titanium-based alloys. 
   
   
       33 . The cutter assembly of  claim 32 , wherein the particle-matrix composite material of the at least one cutting element comprises a plurality of hard particles dispersed throughout a matrix material, the hard particles comprising a material selected from diamond, boron carbide, boron nitride, aluminum nitride, and carbides or borides of the group consisting of W, Ti, Mo, Nb, V, Hf, Ta, Cr, Zr, Al, and Si, the matrix material selected from the group consisting of cobalt-based alloys, iron-based alloys, nickel-based alloys, cobalt and nickel-based alloys, iron and nickel-based alloys, iron and cobalt-based alloys, aluminum-based alloys, copper-based alloys, magnesium-based alloys, and titanium-based alloys. 
   
   
       34 . The cutter assembly of  claim 31 , further comprising at least one bearing structure co-sintered and integral with the cone structure. 
   
   
       35 . The cutter assembly of  claim 34 , wherein the at least one bearing structure comprises a particle-matrix composite material. 
   
   
       36 . The cutter assembly of  claim 31 , wherein the at least one cutting element comprises a cutting insert. 
   
   
       37 . The cutter assembly of  claim 31 , wherein the at least one cutting element comprises at least a portion of a cutting tooth structure. 
   
   
       38 . The cutter assembly of  claim 31 , wherein the second material composition of the at least one cutting element varies between a first region proximate an interface between the at least one cutting element and the cone structure and a second region proximate a formation-engaging surface of the at least one cutting element.