As electronic equipment has become smaller in size, printed circuit boards which cannot be subjected to cleaning have been developed, and a no-clean lead-free solder paste is becoming necessary. In order for a solder paste not to require cleaning, it is necessary that the color of the residue be transparent and that the residue be non-tacky. A maleated rosin, which is a rosin suited for no-clean paste, has a high acid value so it is not suitable for a flux for lead-free solder. As a means of suppressing a reaction between a flux containing a maleated rosin and a Sn—Ag—Cu based solder alloy powder, a Sn—Ag—Cu—Sb based solder alloy powder is used which adds 1-8 mass % of Sb to a Sn—Ag—Cu based solder alloy. As a result, it is possible to provide a solder paste which has the excellent effect that the solder paste does not easily undergo changes over time and has a long pot life.

As electronic equipment has become smaller in size, printed circuit boards which cannot be subjected to cleaning have been developed, and a no-clean lead-free solder paste is becoming necessary. In order for a solder paste not to require cleaning, it is necessary that the color of the residue be transparent and that the residue be non-tacky. A maleated rosin, which is a rosin suited for no-clean paste, has a high acid value so it is not suitable for a flux for lead-free solder. As a means of suppressing a reaction between a flux containing a maleated rosin and a Sn—Ag—Cu based solder alloy powder, a Sn—Ag—Cu—Sb based solder alloy powder is used which adds 1-8 mass % of Sb to a Sn—Ag—Cu based solder alloy. As a result, it is possible to provide a solder paste which has the excellent effect that the solder paste does not easily undergo changes over time and has a long pot life.

A pre-flux coating for the manufacturing of heat exchanger components of aluminum, wherein the coating comprises a combination of fluxes in the form of potassium aluminum fluoride K.sub.1-3AlF.sub.4-6, potassium trifluoro zincate, KZnF.sub.3, lithium aluminum fluoride Li.sub.3AlF.sub.6, a filler material in the form of metallic Si particles, Al—Si particles and/or potassium fluoro silicate K.sub.2SiF.sub.6, an additive in the form of aluminum oxide and at least one other oxide selected from the group consisting of zinc oxide, titanium oxide and cerium oxide forming a post braze ceramic layer, and a solvent and a binder containing at least 10% by weight of a synthetic resin which is based, as its main constituent, on a methacrylate homopolymer or a methacrylate copolymer.

A pre-flux coating for the manufacturing of heat exchanger components of aluminum, wherein the coating comprises a combination of fluxes in the form of potassium aluminum fluoride K.sub.1-3AlF.sub.4-6, potassium trifluoro zincate, KZnF.sub.3, lithium aluminum fluoride Li.sub.3AlF.sub.6, a filler material in the form of metallic Si particles, Al—Si particles and/or potassium fluoro silicate K.sub.2SiF.sub.6, an additive in the form of aluminum oxide and at least one other oxide selected from the group consisting of zinc oxide, titanium oxide and cerium oxide forming a post braze ceramic layer, and a solvent and a binder containing at least 10% by weight of a synthetic resin which is based, as its main constituent, on a methacrylate homopolymer or a methacrylate copolymer.

Provided is a solder material which enables a growth of an oxide film to be inhibited. A solder ball which is a solder material is composed of a solder layer and a covering layer covering the solder layer. The solder layer is spherical and is composed of a metal material containing an alloy including Sn content of 40% and more. Otherwise the solder layer is composed of a metal material including Sn content of 100%. In the covering layer, a S.sub.nO film is formed outside the solder layer, and a S.sub.nO.sub.2 film is formed outside the S.sub.nO film. A thickness of the covering layer is preferably more than 0 nm and equal to or less than 4.5 nm. Additionally, a yellow chromaticity of the solder ball is preferably equal to or less than 5.7.

Provided is a solder material which enables a growth of an oxide film to be inhibited. A solder ball which is a solder material is composed of a solder layer and a covering layer covering the solder layer. The solder layer is spherical and is composed of a metal material containing an alloy including Sn content of 40% and more. Otherwise the solder layer is composed of a metal material including Sn content of 100%. In the covering layer, a S.sub.nO film is formed outside the solder layer, and a S.sub.nO.sub.2 film is formed outside the S.sub.nO film. A thickness of the covering layer is preferably more than 0 nm and equal to or less than 4.5 nm. Additionally, a yellow chromaticity of the solder ball is preferably equal to or less than 5.7.

The present disclosure relates generally to an improved design of a metal-cored welding wire electrode for use on a high deposition rate welding process that resistively preheats the wire prior to being subjected to the welding current. The preheat circuit reduces the welding current drawn by the electrode so that higher wire feed speeds, and thus higher deposition rates, may be obtained. The metal-cored welding wire includes both a higher fill rate (a greater percentage of the welding wire is the granular core) along with added sulfur and an added bead wetting agent. The bead wetting agent may be one or more of selenium, tellurium, arsenic, gallium, bismuth, and tin. The improved metal-cored welding wire leads to an enhanced weld deposit appearance that means the weld deposits are less likely to be rejected as unusable.

A flux according to the present invention contains a rosin methyl ester in which the flux is a solid or solid-like flux at 25° C., and is used for an inside of a flux-cored solder or an exterior of a flux-coated solder.

A pre-coated steel substrate wherein the coating including at least one titanate and at least one nanoparticle; a method for the manufacture of an assembly; a method for the manufacture of a coated steel substrate and a coated substrate substrate. It is particularly well suited for construction, shipbuilding and offshore industries.

A filler feed wire (20) including both a laser conductive element (26) and a filler material (22) extending along a length of the wire. Laser energy (30) can be directed into a proximal end (32) of the laser conductive element for melting a distal end (34) of the feed wire to form a melt pool (24) for additive fabrication or repair. The laser conductive element may serve as a flux material. In this manner, laser energy is delivered precisely to the distal end of the feed wire, eliminating the need to separately coordinate laser beam motion with feed wire motion.