A lead-free solder alloy may comprise tin, silver, copper, bismuth, cobalt, and antimony. The alloy may further comprise nickel. The silver may be present in an amount from about 2.0% to 2.8% by weight of the solder. The copper may be present in an amount from about 0.2% to 1.2% by weight of the solder. The bismuth may be present in an amount from about 0.0% to about 5.0% by weight of the solder. In some embodiments, the bismuth may be present in an amount from about 1.5% to 3.2% by weight of the solder. The cobalt may be present in an amount from about 0.001% to about 0.2% by weight of the solder. The antimony may be present in an amount between about 0.0% to about 0.1% by weight of the solder. The balance of the solder is tin.

A method for step-soldering includes applying a first solder alloy having a melting point in a temperature range from 160 to 210° C. to a jointed portion of a first electronic component and a substrate, and heating them in the temperature range from 160 to 210° C., and applying a second solder alloy having the melting point in a temperature range lower than 160° C. to a joint portion of a second electronic component and the substrate, and heating them in the temperature range lower than 160° C. The first solder alloy consists of 13-22 mass % of In, 0.5-2.8 mass % of Ag, 0.5-5.0 mass % of Bi, 0.002-0.05 mass % of Ni and a balance Sn.

In a copper alloy bonding wire for semiconductor devices, the bonding longevity of a ball bonded part under high-temperature and high-humidity environments is improved. The copper alloy bonding wire for semiconductor devices includes in total 0.03% by mass or more to 3% by mass or less of at least one or more kinds of elements selected from Ni, Zn, Ga, Ge, Rh, In, Ir, and Pt (first element), with the balance Cu and inevitable impurities. The inclusion of a predetermined amount of the first element suppresses production of an intermetallic compound susceptible to corrosion under high-temperature and high-humidity environments at the wire bonding interface and improves the bonding longevity of a ball bonded part.

A method of pretinning a guidewire core made of shape memory alloy and having an elongate axis, comprising: placing a ball of solder in a pocket in a soldering block; melting the ball of solder; holding a guidewire core over the ball of solder; lowering the guidewire core into the ball of solder; removing the guidewire from the ball of solder.

A solder material may include nickel and tin. The nickel may include first and second amounts of particles. A sum of the particle amounts is a total amount of nickel or less. The first amount is between 5 at % and 60 at % of the total amount of nickel. The second amount is between 10 at % and 95 at % of the total amount of nickel. The particles of the first amount have a first size distribution, the particles of the second amount have a second size distribution, 30% to 70% of the first amount have a particle size in a range of about 5 μm around a particle size the highest number of particles have according to the first size distribution, and 30% to 70% of the second amount have a particle size in a range of about 5 μm around a particle size the highest number of particles have according to the second size distribution.

Systems and methods for the manufacture of a solid wire using additive manufacturing techniques are disclosed. In one embodiment, a fine powdery material is sintered or melted or soldered or metallurgically bonded onto a metal strip substrate in a compacted solid form or a near-net shape (e.g., a near-net solid wire shape) before being turned into a final product through forming or drawing dies.

An austenitic stainless steel flux cored wire may provide a welded metal having excellent cryogenic temperature toughness; a welded metal from the wire may have excellent cryogenic temperature toughness; and a welding method may involve such wire(s). An austenitic stainless steel flux cored wire in which a flux is filled in a steel-made shell. The flux cored wire may contain Si, Mn, Ni, Cr, C, P, and N in amounts each falling within a specified range relative to the entire mass of the wire, with the remainder made up by Fe and unavoidable impurities, and X.sub.1 is 17.5 to 22.0 inclusive, as calculated by formula (1):

X.sub.1=[Ni].sub.W+0.5×[Cr].sub.W+1.6×[Mn].sub.W+0.5×[Si].sub.W+15×[C].sub.W  (1),

wherein, in formula (1), [Ni].sub.W, [Cr].sub.W, [Mn].sub.W, [Si].sub.W and [C].sub.W represent the contents (% by mass) of Ni, Cr, Mn, Si, and C, relative to the entire mass of the wire.

A method of pretinning a core wire for a guidewire having an elongate axis, comprising placing a ball of solder within a pocket in a soldering block; melting the ball of solder; holding a core wire over the ball of solder, with the elongate axis in a horizontal orientation; lowering a portion of the core wire into the ball of solder while maintaining the elongate axis in a horizontal orientation; removing the core wire from the ball of solder.

A brazing wire includes a brazing tube having an inner cavity and a flux filled in the inner cavity. A trench is provided on an outer peripheral surface of the brazing tube, and the trench extends along an axis of the brazing tube or spirally extends around the axis. A forming mold of the brazing wire includes a mold body having a molding cavity therein. An inner wall of the molding cavity is provided with a protrusion. When the brazing wire passes through the forming mold, the protrusion is used to form the trench. The forming method of the brazing wire includes the following steps. The brazing tube passes through the forming mold, and the trench is formed on the outer peripheral surface of the brazing tube by the protrusion. The trench extends along the axis of the brazing tube or spirally extends around the axis.

A solder alloy has an alloy composition consisting of, in mass %, Cu: 0.1% to 2.0%, Ni: 0.01% to 0.4%, P: 0.001% to 0.08%, and Ge: 0.001% to 0.08%, with the balance being Sn. The alloy composition satisfies the following relations (1) to (3): (Cu+5Ni)≤0.945% (relation (1)), (P+Ge)≤0.15% (relation (2)), 2.0≤(Cu+5Ni)/(P+Ge)≤1000 (relation (3)). In the above relations (1) to (3), Cu, Ni, P, and Ge each represents a content (mass %) thereof in the solder alloy.