Provided is a preform solder including a first metal containing Sn and a second metal formed of an alloy containing Ni and Fe. Alternatively, provided is a preform solder (1) having a metal structure including a first phase (10) that is a continuous phase and a second phase (20) dispersed in the first phase (10), the first phase (10) contains Sn, the second phase (20) is formed of an alloy containing Ni and Fe, and a grain boundary (15) of a metal is present in the first phase (10).

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 containing an organic acid, a water-soluble base agent, and a solvent, but not containing water is adopted. In this flux, the organic acid includes 1,2,3-propanetricarboxylic acid. The water-soluble base agent is one or more selected from the group consisting of a nonionic surfactant and a weak cationic surfactant. The content of the 1,2,3-propanetricarboxylic acid is 1% by mass or more and 15% by mass or less with respect to the total amount of the entire flux, the total content of the water-soluble base agent is 30% by mass or more and 65% by mass or less with respect to the total amount of the entire flux, and the total content of the solvent is 30% by mass or more and 65% by mass or less with respect to the total amount of the entire flux. According to this flux, the wettability of solder can be enhanced and ball missing after reflow and flux residue washing is suppressed.

A solder alloy that contains 0.005 mass % or more and 0.1 mass % or less of Mn, 0.001 mass % or more and 0.1 mass % or less of Ge, and a balance of Sn. A plurality of Ge oxides is distributed on an outermost surface side of an oxide film including Sn oxide, Mn oxide and Ge oxide by adding 0.005 mass % or more and 0.1 mass % or less of Mn, 0.001 mass % or more and 0.1 mass % or less of Ge to the solder alloy having a principal ingredient of Sn, so that it is possible to obtain the discolor-inhibiting effect even under the high-temperature and high-humidity environment.

A solder alloy that contains 0.005 mass % or more and 0.1 mass % or less of Mn, 0.001 mass % or more and 0.1 mass % or less of Ge, and a balance of Sn. A plurality of Ge oxides is distributed on an outermost surface side of an oxide film including Sn oxide, Mn oxide and Ge oxide by adding 0.005 mass % or more and 0.1 mass % or less of Mn, 0.001 mass % or more and 0.1 mass % or less of Ge to the solder alloy having a principal ingredient of Sn, so that it is possible to obtain the discolor-inhibiting effect even under the high-temperature and high-humidity environment.

The present disclosure relates to a metal particle-containing composition contains at least one thermosetting resin (R), a hardening agent (H), and at least three types of metal particles (P) different from one another. The metal particles (P) contain a solder alloy particle (P1) containing a tin alloy containing at least one metal (A), wherein the metal (A) is a metal that forms a eutectic crystal with tin at a eutectic temperature of 200° C. or lower, at least one metal particle (P2) containing a metal (B) having a melting point exceeding 420° C. in a bulk, the metal particle (P2) having a melting point higher than a solidus temperature of the solder alloy particle (P1), and at least one metal particle (P3) containing a metal (C) that forms an intermetallic compound with a metal contained in the solder alloy particle (P1).

A structure including an Sn layer or an Sn alloy layer includes a substrate, an Sn layer or Sn alloy layer formed above the substrate, and an under barrier metal formed between the substrate and the Sn layer or Sn alloy layer. The under barrier metal is an Ni alloy layer containing Ni, and at least one selected from W, Ir, Pt, Au, and Bi, and can sufficiently inhibit generation of an intermetallic compound through a reaction, caused due to metal diffusion of a metal contained in the substrate, between the metal and Sn contained in the Sn layer or Sn alloy layer.

In a sleeve for a gas nozzle, a sleeve main body and a sleeve end face is formed at least in part by a wear protection element which is fastened to the sleeve main body and which is composed of a more wear-resistant material than the sleeve main body adjoining the sleeve end face, an inner and/or an outer beveled portion of the sleeve end face are formed at least in part by the wear protection element.

In a sleeve for a gas nozzle, a sleeve main body and a sleeve end face is formed at least in part by a wear protection element which is fastened to the sleeve main body and which is composed of a more wear-resistant material than the sleeve main body adjoining the sleeve end face, an inner and/or an outer beveled portion of the sleeve end face are formed at least in part by the wear protection element.

Molded solder includes first metal powder and second metal powder. The first metal powder has a first solidus temperature and a first liquidus temperature and includes an alloy containing metal elements. The second metal powder has a melting temperature or a second solidus temperature and a second liquidus temperature and includes single metal element or an alloy containing metal elements. The melting temperature and the second liquidus temperature are higher than the first liquidus temperature. The molded solder is so constructed that a mixture of the first metal powder and the second metal powder are press-molded. The molded solder is so constructed that a first solidus temperature of a solder becomes higher when the molded solder becomes the solder after the first metal powder has been melted by heating the molded solder at a temperature equal to or higher than the first liquidus temperature.