Abstract: A metal-matrix composite tool includes a matrix region. The matrix region has a reinforcement material, an outer surface, and an inner, localized area spaced apart from the outer surface within the reinforcement material. The reinforcement material has a reinforcement density and the localized area has a localized density different from the reinforcement density. The matrix region has an overall matrix density different from both the reinforcement density and the localized density.

Abstract: Tools, for example, fixed cutter drill bits, may be manufactured to include hard composite portions having reinforcing particles dispersed in a continuous binder phase and auxiliary portions that are more machinable than the hard composite portions. For example, a tool may include a hard composite portion having a machinability rating 0.2 or less; and an auxiliary portion having a machinability rating of 0.6 or greater in contact with the hard composite portion. The boundary or interface between the hard composite portion and the auxiliary portion may be designed so that upon removal of the most or all of the auxiliary portion the resultant tool has a desired geometry without having to machine the hard composite portion.

Abstract: A metal-matrix composite tool includes a matrix region. The matrix region has a reinforcement material, an outer surface, and an inner, localized area spaced apart from the outer surface within the reinforcement material. The reinforcement material has a reinforcement density and the localized area has a localized density different from the reinforcement density. The matrix region has an overall matrix density different from both the reinforcement density and the localized density.

Abstract: A mold assembly and method for fabricating an infiltrated drill bit may comprise a mold forming a bottom of the mold assembly, a funnel operatively coupled to the mold, an infiltration chamber defined at least partially by the mold and the funnel to receive and contain matrix reinforcement materials and a binder material used to form the infiltrated drill bit, a displacement core arranged within the infiltration chamber and having one or more legs that extend therefrom, a metal blank arranged about the displacement core within the infiltration chamber, and one or more thermal elements. A method may comprise providing a mold assembly having component parts that include a mold that forms a bottom of the mold assembly and a funnel operatively coupled to the mold, imparting thermal energy to the infiltration chamber with one or more thermal element, and heating contents contained within the infiltration chamber.

Abstract: Drill bits for use in drilling well bores in subterranean formations, and associated systems and methods of making and using such drill bits, are provided. In certain embodiments, the drill bits comprise: a body; a plurality of blades on the body; a plurality of cutting elements on at least one of the plurality of blades; a reinforcement material forming portions of the body and the plurality of blades; a binder material infiltrated through the reinforcement material to form a composite material and forming portions of the body and the plurality of blades; and at least one interior displacement element located in an interior region of the body that is surrounded by the composite material.

Abstract: A metal-matrix composite includes a reinforced composite material including reinforcement material dispersed in a binder material. The reinforcement material includes a metallic component dispersed with reinforcing particles and at least 25 percent of the metallic component has a particle size of 50 microns or less.

Abstract: A hard composite composition may comprise a binder and a polymodal blend of matrix powder. The polymodal blend of matrix powder may have at least one first local maxima at a particle size of about 0.5 nm to about 30 ?m, at least one second local maxima at a particle size of about 200 ?m to about 10 mm, and at least one local minima between a particle size of about 30 ?m to about 200 ?m that has a value that is less than the first local maxima.

Abstract: A reinforcing metal blank may be used to form metal matrix composite (MMC) drill bits. For example, an MMC drill bit may include a shank attached to a reinforcing metal blank that extends into a bit body comprising a metal matrix composite, wherein the reinforcing metal blank comprises reinforcing structures that are positioned along at least a portion of an inner surface and/or at least a portion of an outer surface of the reinforcing metal blank and extend into the metal matrix composite; and a plurality of cutting elements coupled to an exterior portion of the bit body.

Abstract: A metal matrix composite tool includes a body having hard composite portion that includes reinforcing particles dispersed in a binder material. At least some of the reinforcing particles comprise a monolithic particle structure including a core having irregular outer surface features integral with the core.

Abstract: A metal matrix composite (MMC) may be formed with two or more portions each having different reinforcing particles that enhance strength, wear resistance, or both of their respective portions of the MMC. Selective placement of the different reinforcing particles may be achieved using magnetic members. For example, in some instances, forming an MMC may involve placing reinforcement materials within an infiltration chamber of a mold assembly, the reinforcement materials comprising magnetic reinforcing particles and non-magnetic reinforcing particles; positioning one or more magnetic members relative to the mold assembly to selectively locate the magnetic reinforcing particles within the infiltration chamber with respect to the non-magnetic reinforcing particles; and infiltrating the reinforcement materials with a binder material to form a hard composite.

Abstract: Tools, for example, fixed cutter drill bits, may be manufactured to include hard composite portions having reinforcing particles dispersed in a continuous binder phase and auxiliary portions that are more machinable than the hard composite portions. For example, a tool may include a hard composite portion having a machinability rating 0.2 or less; and an auxiliary portion having a machinability rating of 0.6 or greater in contact with the hard composite portion. The boundary or interface between the hard composite portion and the auxiliary portion may be designed so that upon removal of the most or all of the auxiliary portion the resultant tool has a desired geometry without having to machine the hard composite portion.

Abstract: A mold assembly and method for fabricating an infiltrated drill bit may comprise a mold forming a bottom of the mold assembly, a funnel operatively coupled to the mold, an infiltration chamber defined at least partially by the mold and the funnel to receive and contain matrix reinforcement materials and a binder material used to form the infiltrated drill bit, a displacement core arranged within the infiltration chamber and having one or more legs that extend therefrom, a metal blank arranged about the displacement core within the infiltration chamber, and one or more thermal elements. A method may comprise providing a mold assembly having component parts that include a mold that forms a bottom of the mold assembly and a funnel operatively coupled to the mold, imparting thermal energy to the infiltration chamber with one or more thermal element, and heating contents contained within the infiltration chamber.

Abstract: A low surface friction body for a drill bit includes a matrix drill bit body. The body includes a particulate phase having a friction-reducing additive, and a binding material that bonds the particulate phase using a suitable manufacturing process such as selective laser sintering. The particulate phase may include tungsten carbide, the friction-reducing additive may be polytetrafluoroethylene, and the binder material may be copper or cobalt. The friction-reducing additive is distributed throughout at least a portion of the drill bit body that includes the surface that will come into contact with drill cuttings and drilling fluid during operation. The molecular properties of the friction-reducing additive result in a drill bit body having a surface that is resistant to sticking even after enduring chipping and other types of wear.

Abstract: An example mold assembly for fabricating an infiltrated downhole tool includes a mold defining a bottom of the mold assembly and a funnel operatively coupled to the mold. An infiltration chamber is defined at least partially by the mold and the funnel to receive and contain matrix reinforcement materials and a binder material used to form the infiltrated downhole tool. A thermal mass is positioned within the infiltration chamber above the infiltrated downhole tool for imparting heat to the infiltrated downhole tool following an infiltration process.

Abstract: Forming a precipitation hardened composite material having reinforcing particles and precipitated intermetallic particles dispersed in the binder material may involve heat treating the hard composite material at a temperature above a solvus line for the binder material and below a melting point of the binder material and quenching the hard composite material to a temperature below the solvus line of the binder material. At least some of the precipitated intermetallic particles in the precipitation hardened composite material may have at least one dimension less than 1 micron. Such precipitated intermetallic particles may optionally be grown to larger sizes by heat treating the precipitation hardened composite material at a temperature below the solvus line of the binder material.

Abstract: Tools, for example, fixed cutter drill bits, may be manufactured to include hard composite portions having reinforcing particles dispersed in a continuous binder phase and auxiliary portions that are more machinable than the hard composite portions. For example, a tool may include a hard composite portion having a machinability rating 0.2 or less; and an auxiliary portion having a machinability rating of 0.6 or greater in contact with the hard composite portion. The boundary or interface between the hard composite portion and the auxiliary portion may be designed so that upon removal of the most or all of the auxiliary portion the resultant tool has a desired geometry without having to machine the hard composite portion.

Abstract: Structural metal-matrix composites (MMC) comprising a foam matrix material infiltrated with a binder material, where the binder material binds the foam matrix material to a structural element of a tool, thereby enhancing three-dimensional reinforcement of the tool. In some instances, the structural element is a portion of a wellbore tool or a bit body, such that portions of such tools or bit bodies are composed of the structural MMC. The foam matrix material may be composed of a metallic foam, a ceramic foam, and any combination thereof.

Abstract: An example mold assembly for fabricating an infiltrated downhole tool includes a mold forming a bottom of the mold assembly, and a funnel operatively coupled to the mold. An infiltration chamber is defined at least partially by the mold and the funnel to receive and contain matrix reinforcement materials and a binder material used to form the infiltrated downhole tool. One or more thermal elements are positioned within at least one of the mold and the funnel, and the one or more thermal elements are in thermal communication with the infiltration chamber.

Abstract: A mold transfer assembly includes a transfer housing providing an interior defined by one or more sidewalls and a top. The transfer housing is sized to receive and encapsulate a mold as the mold is moved between a furnace and a thermal heat sink. An arm is coupled to the transfer housing to move the transfer housing and the mold encapsulated within the transfer housing between the furnace and a thermal heat sink. The transfer housing exhibits one or more thermal properties to control a thermal profile of the mold.

Abstract: Drill bits for use in drilling well bores in subterranean formations, and associated systems and methods of making and using such drill bits, are provided. In certain embodiments, the drill bits comprise: a body; a plurality of blades on the body; a plurality of cutting elements on at least one of the plurality of blades; a reinforcement material forming portions of the body and the plurality of blades; a binder material infiltrated through the reinforcement material to form a composite material and forming portions of the body and the plurality of blades; and at least one interior displacement element located in an interior region of the body that is surrounded by the composite material.