A part includes a three-dimensional porous metallic workpiece printed via an additive manufacturing process and subsequently subjected to a diffusion-based process to convert at least a portion of the porous metallic workpiece to a ceramic workpiece or an intermetallic workpiece.

This disclosure includes the description of a braze alloy composition. The braze composition contains nickel, about 5% by weight to about 25% by weight germanium; and about 1% by weight to about 4% by weight boron. The composition has an amorphous structure, and is free of silicon.

Hardfacing is used to protect wear surfaces of drill bits and other downhole tools. A hardfacing member can be formed by heating a metal matrix material, e.g., via a laser process, injecting a plurality of particles into the heated metal matrix material, disposing the mixture on at least a portion of a substrate thereby forming a hardfacing member having a particle-embedded metal matrix material, and attaching the hardfacing member to a main body.

Methods for welding a particle-matrix composite body to another body and repairing particle-matrix composite bodies are disclosed. Additionally, earth-boring tools having a joint that includes an overlapping root portion and a weld groove having a face portion with a first bevel portion and a second bevel portion are disclosed. In some embodiments, a particle-matrix bit body of an earth-boring tool may be repaired by removing a damaged portion, heating the particle-matrix composite bit body, and forming a built-up metallic structure thereon. In other embodiments, a particle-matrix composite body may be welded to a metallic body by forming a joint, heating the particle-matrix composite body, melting a metallic filler material forming a weld bead and cooling the welded particle-matrix composite body, metallic filler material and metallic body at a controlled rate.

A part includes a three-dimensional porous metallic workpiece printed via an additive manufacturing process and subsequently subjected to a diffusion-based process to convert at least a portion of the porous metallic workpiece to a ceramic workpiece or an intermetallic workpiece.

The method of manufacturing a tool part includes the steps of providing a first shaft portion and a separate second shaft portion formed of a different material to the first shaft portion, the first shaft portion having a first contacting face at an end thereof, and the second shaft portion having a second contacting face at an end thereof. The method also includes aligning the first and second shaft portions along a common central axis; contacting the first contacting face with the second contacting face; and passing a current through the first and second shaft portions. The temperature increases at an interface between the first and second contacting faces, and pressure is simultaneously applied between the first and second shaft portions in a direction of the common central axis, thereby welding the first shaft portion to the second shaft portionto form a shaft of the tool part.

A downhole component including a first portion; a second portion; a controlled failure structure between the first portion and second portion. A method for improving efficiency in downhole components.

A bit for drilling with a casing or liner string includes: a tubular stem made from a high strength metal or alloy; a head: having a cutting face with an inner cone, an outer shoulder, and an intermediate nose between the cone and the shoulder; attached to an end of the stem; and made from a nonferrous metal or alloy; a plurality of blades formed integrally with the head, made from the nonferrous metal or alloy, and each extending from a center of the cutting face to the shoulder; a plurality of superhard cutters mounted along each blade; a plurality of gauge pads formed integrally with the stem; and a flush joint formed between each blade and a respective gauge pad. A yield strength of the high strength metal or alloy is at least twice a yield strength of the nonferrous metal or alloy.

Earth-boring tools may include a body having blades protruding therefrom and at least one hardfacing pad secured to at least one blade. The at least one hardfacing pad may be located at least partially within a recess extending at least into the at least one blade body around a circumference of a gage region of the body and may include a plate, an abrasion-resistant material secured to the plate on a side of the plate opposite the body, and at least one spacer extending from the plate toward the body, such that the plate is spaced from the body by at least a thickness of the at least one spacer. A braze material may secure the at least one hardfacing pad to the at least one blade, the braze material extending around the at least one spacer and located between the plate and the body.

A downhole component including a first portion; a second portion; a controlled failure structure between the first portion and second portion. A method for improving efficiency in downhole components.