Structures for a tool surface of a downhole tool are constructed from a metal clay molded in a wet state. The wet state clay is a workable combination that can have a braze alloy grain, a tungsten carbide grain, and a binder. Additional cutting inserts can be embedded in the molded clay. Heat treatment applied to the molded metal clay causing the binder to be combusted and consumed. The braze alloy melts and then cools into a fused state with the tungsten carbide grain therein. The structure can affix to the tool surface of the tool by first being fused and then attached by brazing to the tool. Alternatively, the structure can be positioned in a fusible state adjacent the tool surface. When the heat treatment is applied, the structure fuses together and forms a metallurgical bond with the tool surface of the tool.

Described herein are compositions for use in the brazing of metal substrates. Methods of making and using these compositions are also described herein.

A flux according to the present invention includes a phosphine oxide. It is thereby possible to provide a flux capable of improving solder wettability, a resin flux cored solder including the flux, and a solder paste including the flux.

Provided is a solder composition including a flux, a solder alloy, and a silicone oil. The solder composition can have a kinematic viscosity at 25° C. of 5000 mm.sup.2/s or more and 200,000 mm.sup.2/s or less. The silicone oil can be at least one member selected from the group consisting of dimethyl silicone oil, methylphenyl silicone oil, methylhydrogen silicone oil, reactive silicone oil, and non-reactive silicone oil.

A solder paste includes a solder powder and a flux. The flux includes a rosin, an activator, a solvent, and a thixotropic agent containing a polyethylene glycol. A content of the polyethylene glycol is 10 mass % to 20 mass % with respect to a total mass of the flux, a content of the thixotropic agent excluding the polyethylene glycol is 5 mass % or less with respect to the total mass of the flux, and a content of the rosin is more than 15 mass % and 50 mass % or less with respect to the total mass of the flux.

An objective of the present invention is to provide a flux that suppresses occurrence of flux drying up during soldering and occurrence of precipitation during storing.

The flux comprising, based on the whole flux, 3.5 to 11% by mass of a rosin ester, more than 0% by mass and 18% by mass or less of a rosin resin other than a rosin ester, and 70% by mass or more and less than 96.5% by mass of a solvent.

A flux resin composition includes an epoxy resin, an imidazole compound, a thixo agent, and an activator. The epoxy resin includes at least one resin selected from the group consisting of naphthalene epoxy resins, biphenyl aralkyl epoxy resins, trisphenol methane epoxy resins, biphenyl epoxy resins, and dicyclopentadiene epoxy resins. The content of the at least one resin is equal to or greater than 20% by weight with respect to a total weight of the epoxy resin.

The preparation and use of particulate metallic solder alloy having particles of a single chemical composition is described. The particles of the particulate metallic solder alloy have a bimodal size distribution in which particles in a smaller size range have a largest dimension that is smaller than a smallest dimension of particles in a larger size range of the bimodal distribution. In some examples the particles in the smaller size mode have dimensions in the range of 1 to 100 nm. In some examples, the particles in the larger size mode have dimensions in the range of 2 to 75 microns in dimension. In some examples, a halogen-free flux is used. In some examples, a solvent is used to make a paste.

A flux composition includes a component (A) that is a powder of an alkali metal zinc fluoroaluminate represented by “M.sub.wZn.sub.xAl.sub.yF.sub.z (1)” (wherein M is K or Cs, and w, x, y, and z are a positive integer, the greatest common divisor of w, x, y, and z being 1), the content of the component (A) in the flux composition being 50 mass % or more. The flux composition prevents occurrence of a brazing defect and discoloration even when an aluminum alloy is brazed in an atmosphere having a high oxygen concentration, or an atmosphere having high humidity.

A flux-cored wire for gas-shielded arc welding has a steel outer sheath filled with a flux. The flux-cored wire includes specific amounts, relative to a total mass of the wire, of TiO.sub.2, at least one of Si, an Si oxide and an Si compound, C, Mn, Mo, Ni, at least one of metal Mg and an Mg alloy, an F compound, a K compound, an Na compound, B and a B compound, and Fe, respectively. A total content of each of Ti and a Ti alloy, metal Al and an Al alloy, and V is restricted to the specific range, respectively. A content of Ti is also restricted to the specific range relative to the total mass of the steel outer sheath.