One object of the present invention is to provide a bonding material capable of forming a highly reliable bond, the present invention provides a bonding material having a plate shape or a sheet shape, wherein the bonding material includes: fine copper particles having an average particle diameter of 300 nm or less; coarse copper particles having an average particle diameter of 3 .Math.m or more and 11 .Math.m or less; and a reducing agent which reduces the fine copper particles and the coarse copper particles.

One object of the present invention is to provide a bonding material capable of forming a highly reliable bond, the present invention provides a bonding material having a plate shape or a sheet shape, wherein the bonding material includes: fine copper particles having an average particle diameter of 300 nm or less; coarse copper particles having an average particle diameter of 3 .Math.m or more and 11 .Math.m or less; and a reducing agent which reduces the fine copper particles and the coarse copper particles.

Provided is a Cu-based alloy powder that is suitable for a process involving rapid melting and rapid solidification and that can provide a shaped object superior in characteristics. The powder is composed of a Cu-based alloy, which contains an element M being one or more elements selected from Cr, Fe, Ni, Zr, and Nb: 0.1% by mass or more and 10.0% by mass or less, Si: more than 0% by mass and 0.20% by mass or less, P: more than 0% by mass and 0.10% by mass or less, and S: more than 0% by mass and 0.10% by mass or less, the balance being Cu and inevitable impurities. This powder has a ratio (D50/TD) of the average particle diameter D50 (μm) thereof to the tap density TD (Mg/m.sup.3) is 0.2×10.sup.−5.Math.m.sup.4/Mg or more and 20×10.sup.−5.Math.m.sup.4/Mg or less, and has a sphericity of 0.80 or more and 0.95 or less.

In the joined body (10) in which the conductor (12) and the substrate (14) are joined by the joining material (13), the joining material (13) includes a sintered body formed by sintering silver powder. A sintered body having a porosity of 8% to 30% and a surface roughness Ra of a joining surface of 500 nm or more and 3.3 μm or less is adopted.

Alloy powder comprises particles. The particles include specific particles. Each of the specific particles has a surface layer on which a divided trace is formed.

A dust core contains a powder of a crystalline magnetic material powder and a powder of an amorphous magnetic material. The sum of the content of the crystalline magnetic material powder and the content of the amorphous magnetic material powder is 83 mass percent or more. The mass ratio of the content of the crystalline magnetic material powder to the sum of the content of the crystalline magnetic material powder and the content of the amorphous magnetic material powder is 20 mass percent or less. The median diameter D50a of the amorphous magnetic material powder is greater than or equal to the median diameter D50c of the crystalline magnetic material powder. A 10% cumulative diameter D10a in a volume-based cumulative particle size distribution of the amorphous magnetic material powder is 9.5 μm or less.

A dust core contains a powder of a crystalline magnetic material powder and a powder of an amorphous magnetic material. The sum of the content of the crystalline magnetic material powder and the content of the amorphous magnetic material powder is 83 mass percent or more. The mass ratio of the content of the crystalline magnetic material powder to the sum of the content of the crystalline magnetic material powder and the content of the amorphous magnetic material powder is 20 mass percent or less. The median diameter D50a of the amorphous magnetic material powder is greater than or equal to the median diameter D50c of the crystalline magnetic material powder. A 10% cumulative diameter D10a in a volume-based cumulative particle size distribution of the amorphous magnetic material powder is 9.5 μm or less.

A metal part with a wall thickness less than 5 mm includes a preform made from a flexible composite sheet, a flexible composite sheet segment, and an appended insert including a fastening portion that is sandwiched between a rear end of the preform and the flexible composite sheet segment. The flexible composite sheet segment encloses the fastening portion of the appended insert.

A metal part with a wall thickness less than 5 mm includes a preform made from a flexible composite sheet, a flexible composite sheet segment, and an appended insert including a fastening portion that is sandwiched between a rear end of the preform and the flexible composite sheet segment. The flexible composite sheet segment encloses the fastening portion of the appended insert.

A three-dimensional chiral nanostructure according to an embodiment of the present invention comprises: metal nanoparticles having a chiral structure: and a coating layer enclosing the metal nanoparticles. The metal nanoparticle is formed in a polyhedral structure having an R region and an S region in which atoms are arranged clockwise and counterclockwise, respectively, in the order of (111), (100), and (110) crystal faces on the basis of the chiral center, wherein at least a portion of the edges form a curve tilting and extending from the R or S region so that the metal nanoparticle has a chiral structure.