A metal paste that includes a metal component and a flux. The metal component includes a first metal powder and a second metal powder. The first metal powder is Sn. The second metal powder is a CuNi alloy. The metal paste is heated for a time t1 to a temperature T1 where the first metal powder is melted. Next, the metal paste is heated for a time t2 longer than the time t1 at a temperature T2 lower than the temperature T1 to produce an intermetallic compound from the first metal Sn and the second metal CuNi alloy.

A solder composition for use in solder joints of printed circuit boards (PCBs), including a compound layer comprising an alloy of bismuth and tin; and a graphene coating positioned on the compound layer.

A solder composition for use in solder joints of printed circuit boards (PCBs), including a compound layer comprising an alloy of bismuth and tin; and a graphene coating positioned on the compound layer.

A solder alloy, a solder powder and the like, which suppresses change in a solder paste over time and has excellent wettability, a small temperature difference between the liquidus temperature and the solidus temperature, and excellent mechanical properties, and exhibits a high joint strength, are provided. The solder alloy has an alloy composition containing 0.55 to 0.75 mass % of Cu, 0.0350 to 0.0600 mass % of Ni, 0.0035 to 0.0200 mass % of Ge, and 25 to 300 mass ppm of As, at least either one of 0 to 3000 mass ppm of Sb, 0 to 10000 mass ppm of Bi, and 0 to 5100 mass ppm of Pb, and a balance of Sn, and satisfies Expressions (1) to (3) below.

275≤2As+Sb+Bi+Pb  (1)

0.01≤(2As+Sb)/(Bi+Pb)≤10.00  (2)

10.83≤Cu/Ni≤18.57  (3)

In Expressions (1) to (3) shown above, Cu, Ni, As, Sb, Bi, and Pb each represent an amount (mass ppm) in the alloy composition.

An aluminum alloy brazing sheet is formed of a four-layer material formed of a brazing material, an intermediate material, a core material, and a. brazing material. The intermediate material comprises Mg of 0.40 to 6.00 mass %, and has a total of contents of Mn, Cr, and Zr being 0.10 mass % or more. The core material comprises Mg of 0.20 to 2.00 mass % and comprises one or two or more of Mn of 1.80 mass % or less, Si of 1.05 mass % or less, Fe of 1.00 mass % or less, Cu of 1.20 mass % or less, Ti of 0.30 mass % or less, Zr of 0.30 mass % or less, and Cr of 0.30 mass % or less. Each of the core material and the intermediate material has a grain size of 20 to 300 μm.

The invention relates to a welding electrode for resistance welding, formed by a welding tool made of a metal, the welding tool having a contact surface that comes into contact with the workpiece to be welded. In order to avoid adhesion between the contact surface and a workpiece made, in particular of aluminum, it is suggested in the invention that the contact surface is made of diamond doped with boron.

A method for producing an aluminum alloy clad material having a core material and a sacrificial anode material clad on at least one surface of the core material, wherein the core material comprises an aluminum alloy comprising 0.050 to 1.5 mass % (referred to as “%” below) Si, 0.050 to 2.0% Fe and 0.50 to 2.00% Mn; the sacrificial anode material includes an aluminum alloy containing 0.50 to 8.00% Zn, 0.05 to 1.50% Si and 0.050 to 2.00% Fe; the grain size of the sacrificial anode material is 60 μm or more; and a ratio R1/R2 is 0.30 or less, wherein R1 (μm) is a grain size in a thickness direction and R2 (μm) is a grain size in a rolling direction in a cross section of the core material along the rolling direction; a production method thereof; and a heat exchanger using the clad.

A method for producing an aluminum alloy clad material having a core material and a sacrificial anode material clad on at least one surface of the core material, wherein the core material comprises an aluminum alloy comprising 0.050 to 1.5 mass % (referred to as “%” below) Si, 0.050 to 2.0% Fe and 0.50 to 2.00% Mn; the sacrificial anode material includes an aluminum alloy containing 0.50 to 8.00% Zn, 0.05 to 1.50% Si and 0.050 to 2.00% Fe; the grain size of the sacrificial anode material is 60 μm or more; and a ratio R1/R2 is 0.30 or less, wherein R1 (μm) is a grain size in a thickness direction and R2 (μm) is a grain size in a rolling direction in a cross section of the core material along the rolling direction; a production method thereof; and a heat exchanger using the clad.

A radial bearing having a wear surface with improved wear characteristics comprises a steel support, to which is bonded a metal carbide composite wear surface made by first arranging, within a cavity defined between a steel mold and the steel support, tiles made of microwave sintered, cemented metal carbide, closely packing the voids between the tiles with metal carbide powder, and infiltrating the mold cavity with a metal brazing alloy by subjecting the filled mold to rapid heating. The brazing alloy fills voids between the metal carbide particles, the microwave sintered metal carbide tiles, and the metal support, thereby relatively rapidly consolidating the carbide into a wear layer bonded with the steel support without substantially damaging the properties of the microwave-sintered metal carbide tiles.

An aluminum alloy brazing sheet used for brazing of an aluminum material in an inert gas atmosphere or in vacuum is formed of a two-layer material in which a brazing material and a core material are stacked in this order. The core material is formed of an aluminum alloy and has a grain size of 20 to 300 μm, and the aluminum alloy includes Mn of 0.50 to 2.00 mass %, Mg of 0.40 to 2.00 mass %, Si of 1.50 mass % or less, and Fe of 1.00 mass % or less. The brazing material is formed of an aluminum alloy including Si of 4.00 to 13.00 mass % and one or two or more of Mn of 2.00 mass or less, Ti of 0.30 mass % or less, Zr of 0.30 mass % or less, and Cr of 0.30 mass % or less.