摘要:
A method of modifying surfaces of diamond particles comprises forming spinodal alloy coatings over discrete diamond particles, thermally treating the spinodal alloy coatings to form modified coatings each independently exhibiting a reactive metal phase and a substantially non-reactive metal phase, and etching surfaces of the discrete diamond particles with at least one reactive metal of the reactive metal phase of the modified coatings. Diamond particles and earth-boring tools are also described.
摘要:
A cutting element for an earth-boring tool includes a substrate and volume of superabrasive material positioned on the substrate. The volume of superabrasive material includes a cutting face having at least one recess extending into the volume of superabrasive material and/or at least one protrusion extending outward from the volume of superabrasive material. The volume of superabrasive material includes a first chamfer surface having a peripheral edge and a radially innermost edge. The peripheral edge of the first chamfer surface is located proximate a cutting edge of the volume of superabrasive material. A radial width of the first chamfer surface is between about 0.002 inch and about 0.045 inch. The volume of superabrasive material also includes a second chamfer surface having a peripheral edge and a radially innermost edge. The peripheral edge of the second chamfer surface is located adjacent the radially innermost edge of the first chamfer surface.
摘要:
A polycrystalline compact comprises a plurality of diamond grains of micron size, submicron size, or both, and a plurality of diamond nanoparticles disposed in interstitial spaces between the plurality of diamond grains. A method of forming a polycrystalline compact comprises combining a plurality of micron and/or submicron-sized diamond grains and a plurality of diamond nanoparticles to form a mixture and sintering the mixture in a presence of a carburized binder to form a polycrystalline hard material comprising a plurality of inter-bonded diamond grains and diamond nanoparticles. Cutting elements comprising a polycrystalline compact and earth-boring tools bearing such compacts are also disclosed.
摘要:
Polycrystalline compacts include a polycrystalline superabrasive material comprising a first plurality of grains of superabrasive material having a first average grain size and a second plurality of grains of superabrasive material having a second average grain size smaller than the first average grain size. The first plurality of grains is dispersed within a substantially continuous matrix of the second plurality of grains. Earth-boring tools may include a body and at least one polycrystalline compact attached thereto. Methods of forming polycrystalline compacts may include coating relatively larger grains of superabrasive material with relatively smaller grains of superabrasive material, forming a green structure comprising the coated grains, and sintering the green structure. Other methods include mixing diamond grains with a catalyst and subjecting the mixture to a pressure greater than about five gigapascals (5.0 GPa) and a temperature greater than about 1,300°C to form a polycrystalline diamond compact.
摘要:
Methods for forming cutting elements, methods for forming polycrystalline compacts, and related polycrystalline compacts are disclosed. Grains of a hard material are subjected to a high pressure, high temperature process to form a polycrystalline compact. Inclusion of at least one relatively quick spike in system pressure or temperature during an otherwise plateaued temperature or pressure stage accommodates formation of inter-granular bonds between the grains. The brevity of the peak stage may avoid undesirable grain growth. Embodiments of the methods may also include at least one of oscillating at least one system condition (e.g., pressure, temperature) and subjecting the grains to ultrasonic or mechanical vibrations. A resulting polycrystalline compact may include a high density of inter-granularly bonded hard material with a minimized amount of catalyst material, and may provide improved thermal stability, wear resistance, toughness, and behavior during use of a cutting element incorporating the polycrystalline compact.
摘要:
Cutting elements comprise a substrate, a polycrystalline table, and an asymmetric interface feature. The interface feature comprises a shape that is reflectively asymmetric about at least two planes defined by x, y, and z axes of a Cartesian coordinate system defined to align a z axis of the coordinate system with the central axis of the substrate and to locate a center of the coordinate system at a midpoint along an axial height of the asymmetric interface feature. Methods of forming a cutting element comprise: forming an asymmetric interface feature at an end of a substrate; distributing a plurality of superhard particles on the substrate over the asymmetric interface feature in a mold; and bonding the superhard particles in the mold to form a polycrystalline table attached to the substrate.
摘要:
Cutting elements, earth-boring drill bits having such cutting elements and related methods are described herein. In some embodiments, a cutting element for an earth-boring tool may include a diamond table having an indentation in a cutting face thereof and a shaped feature in a substrate at the interface between the diamond table and the substrate, the shaped feature corresponding to the indentation in the cutting face of the diamond table. In further embodiments, a cutting element for an earth-boring tool may include a sacrificial structure positioned within an indentation in a diamond table. In additional embodiments, a method of forming a cutting element may include positioning a sacrificial structure in a mold, positioning a powdered precursor material over the sacrificial structure, and pressing and sintering the powdered precursor material to form a diamond table having an indentation in a cutting face formed by the sacrificial structure.
摘要:
Earth-boring tools may comprise a body comprising a first region and a second region. The first region may be located closer to a rotational axis of the body than the second region. A first cutting element may be located in the first region and a second cutting element may be located in the second region. A first polycrystalline table of the first cutting element may be substantially free of catalyst material to a first depth and a second polycrystalline table of the second cutting element may be substantially free of catalyst material to a second, greater depth.
摘要:
Polycrystalline compacts include a hard polycrystalline material comprising first and second regions. The first region comprises a first plurality of grains of hard material having a first average grain size, and a second plurality of grains of hard material having a second average grain size smaller than the first average grain size. The first region comprises catalyst material disposed in interstitial spaces between inter-bonded grains of hard material. Such interstitial spaces between grains of the hard material in the second region are at least substantially free of catalyst material. In some embodiments, the first region comprises a plurality of nanograins of the hard material. Cutting elements and earth-boring tools include such polycrystalline compacts. Methods of forming such polycrystalline compacts include removing catalyst material from interstitial spaces within a second region of a polycrystalline compact without entirely removing catalyst material from interstitial spaces within a first region of the compact.
摘要:
Polycrystalline compacts include non-catalytic, non-carbide-forming particles in interstitial spaces between interbonded grains of hard material in a polycrystalline hard material. Cutting elements and earth-boring tools include such polycrystalline compacts. Methods of forming polycrystalline compacts include forming a polycrystalline material including a hard material and a plurality of particles comprising a non-catalytic, non-carbide-forming material. Methods of forming cutting elements include infiltrating interstitial spaces between interbonded grains of hard material in a polycrystalline material with a plurality of non-catalytic, non-carbide-forming particles.