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.

Embodiments of the present invention provide a method (1000) of assembling an electrical circuit comprising one or more copper electrical conductors, the method comprising plating (1010) a surface of the one or more conductors with a layer comprising tin; annealing the plating; applying (1020) solder to at least a portion of the one or more electrical conductors, wherein said solder comprises tin and copper; and annealing the electrical circuit.

A lead-free solder alloy includes bismuth (Bi), content of which is equal to or greater than 56 wt % and equal to or less than 57.5 wt %, indium (In), content of which is equal to or greater than 0.05 wt % and equal to or less than 1.0 wt %, and the balance of tin (Sn) and another unavoidable impurity. The lead-free solder alloy of the disclosure may enable bonding with improved ductility and thermal shock reliability while not having a large melting point change compared to an Sn-58Bi alloy.

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.

A resin flux solder paste includes a solder powder, and a flux, in which the flux contains at least an epoxy resin, a curing agent, a curing accelerator, and an activator, the epoxy resin contains 10% to 90% by weight of one or more of a biphenyl aralkyl type epoxy resin, a naphthalene type epoxy resin, and a dicyclopentadiene type epoxy resin, having an epoxy equivalent of 200 to 400, with respect to a total amount of the epoxy resin, and the curing agent contains 30% to 95% by weight of a biphenyl aralkyl phenol resin having a hydroxyl group equivalent of 150 to 350 with respect to a total amount of the curing agent, and 5% to 70% by weight of a phenol novolac resin having an allyl group having a hydroxyl group equivalent of 100 to 200 with respect to the total amount of the curing agent.

A metal composition that includes a metal component and a flux. The metal component is composed of a first metal powder of a Sn-based metal, and a second metal powder of a Cu-based metal that has a higher melting point than the Sn-based metal. The flux includes a rosin, a solvent, a thixotropic agent, an activator, and the like. When the metal composition is heated to a temperature equal to or higher than the melting point of the first metal powder, the first metal powder is melted. The melted Sn and the CuNi alloy powder produce an intermetallic compound phase of a CuNiSn alloy through a TLP reaction.

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.

A solder material for use in electronic assembly, the solder material comprising: solder layers; and a core layer comprising a core material, the core layer being sandwiched between the solder layers, wherein: the thermal conductivity of the core material is greater than the thermal conductivity of the solder.

According to some aspects, techniques are described for designing non-insulated (NI) high temperature superconductor (HTS) magnets that mitigate problems that may arise during quench initiation and propagation. Coupling the HTS material to a co-conductor along its length reduces the effective resistance of the conductive path along the HTS material when it is not superconducting, and that this leads to numerous advantages for quench mitigation.