The present invention is an alloy that contains Fe, B, P, and Cu, and includes a non-crystalline phase and a plurality of crystalline phases formed in the non-crystalline, wherein an average Fe concentration in a whole alloy is 79 atomic % or greater, and wherein a density of Cu clusters when a region with a Cu concentration of 6.0 atomic % or greater among regions with 1.0 nm on a side in atom probe tomography is determined to be a Cu cluster is 0.20×10.sup.24/m.sup.3.

An alloy including an amorphous phase, and the alloy includes: an average Fe concentration in an entire alloy of 82.0 at. % or more and 88.0 at. % or less; an average Cu concentration in the entire alloy of 0.4 at. % or more and 1.0 at. % or less; an average P concentration in the entire alloy of 5.0 at. % or more and 9.0 at. % or less; an average B concentration in the entire alloy of 6.0 at. % or more and 10.0 at. % or less; an average Si concentration in the entire alloy of 0.4 at. % or more and 1.9 at. % or less; an average C concentration in the entire alloy of 0 at. % or more and 2.0 at. % or less; an average impurity concentration of an impurity other than Fe, Cu, P, B, Si, and C in the entire alloy of 0 at. % or more and 0.3 at. % or less; and a total of the average Fe concentration, the average Cu concentration, the average P concentration, the average B concentration, the average Si concentration, the average C concentration, and the average impurity concentration of 100.0 at. %.

The present concepts include a zero-porosity structure having a plurality of structural elements arranged to provide a negative Poisson's ratio and, further, a new mechanism to generate negative Poisson's ratio is single material, zero-porosity structure.

The present disclosure provides a method that ensures easily manufacturing an alloy ribbon piece having excellent soft magnetic properties. The method is a method for manufacturing an alloy ribbon piece obtained by crystallizing an amorphous alloy ribbon piece and including: increasing a temperature of the amorphous alloy ribbon piece to a crystallization starting temperature; and increasing the temperature of the amorphous alloy ribbon piece from the crystallization starting temperature to a crystallization process termination temperature equal to or less than a crystallization completion temperature. A temperature increase rate of the amorphous alloy ribbon piece in the increasing of the temperature of the amorphous alloy ribbon piece from the crystallization starting temperature to the crystallization process termination temperature satisfies ΔQ.sub.self≤ΔQ.sub.out+mcΔT where a self-heating amount, a heat discharge amount, a mass, a specific heat, and a temperature increase width of the amorphous alloy ribbon piece per unit time is ΔQ.sub.self, ΔQ.sub.out, m, c, and ΔT, respectively.

There is provided a method for producing metal foils, capable of easily crystalizing amorphous soft magnetic material of a plurality of metal foils into nano-crystal soft magnetic material by uniformly heating the metal foils. A laminate obtained by laminating the metal foils made of amorphous soft magnetic material is held by a holding member such that adjacent metal foils can be separated from each other in a laminated direction of the laminate. By conveying either the holding member or magnets in a direction perpendicular to the laminated direction as a conveying direction such that the holding member and the magnets come close to each other, the adjacent metal foils are separated from each other with a magnetic force of the magnets. The separated metal foils are heated to crystalize the amorphous soft magnetic material of the metal foils into nano-crystal soft magnetic material. The same magnetic pole of the magnets aligns in the laminated direction.

An Fe-based amorphous alloy ribbon reduced in iron loss, less deformed, and highly productive in a condition of a magnetic flux density of 1.45 T is provided. One aspect of the present disclosure provides an Fe-based amorphous alloy ribbon having first and second surfaces, and is provided with continuous linear laser irradiation marks on at least the first surface. Each linear laser irradiation mark is formed along a direction orthogonal to a casting direction of the Fe-based amorphous alloy ribbon, and has unevenness on its surface. When the unevenness is evaluated in the casting direction, a height difference HL×width WA calculated from the height difference HL between a highest point and a lowest point in a thickness direction of the Fe-based amorphous alloy ribbon and the width WA which is a length of the linear irradiation mark on the first surface is 6.0 to 180 μm.sup.2.

An alloy includes: an average Ni concentration of 1.5 at.% or more and 15.5 at.% or less; an average Co concentration of 0 at.% or more and 10.0 at.% or less; an average B concentration of 3.0 at.% or more and 16.0 at.% or less; an average P concentration of 0.5 at.% or more and 10.0 at.% or less; an average Cu concentration of 0 at.% or more and 2.0 at.% or less; an average Si concentration of 0 at.% or more and 6.0 at.% or less; an average C concentration of 0 at.% or more and 6.0 at.% or less; a total of average concentrations of Nb, Mo, Zr, W, V, Hf, Ta, Al, Ti, and Cr of 0 at.% or more and 6.0 at.% or less; and a total of an average Fe concentration, the average Ni concentration, and the average Co concentration of 78.0 at.% or more and 88.0 at.% or less.

A method for manufacturing an alloy ribbon piece capable of manufacturing a nanocrystalline alloy ribbon piece is provided. The method for manufacturing an alloy ribbon piece according to the present disclosure is a method for manufacturing an alloy ribbon piece obtained by crystallizing an amorphous alloy ribbon piece, and includes: preparing the amorphous alloy ribbon piece; sequentially heating the amorphous alloy ribbon piece from one end to an intermediate position toward another end to a temperature range equal to or more than a crystallization starting temperature, and stopping the heating when heating the amorphous alloy ribbon piece up to the intermediate position to the temperature range; and heating a region on the other end side with respect to the intermediate position of the amorphous alloy ribbon piece to the temperature range equal after the stopping of the heating in the sequentially heating.

A method for manufacturing a nanocrystalline alloy ribbon piece with high productivity is provided. The method according to the present disclosure is a method for manufacturing an alloy ribbon piece obtained by crystallizing an amorphous alloy ribbon piece, and includes: preparing the amorphous alloy ribbon piece; sequentially heating the ribbon piece from one end to an intermediate position toward another end to a temperature range equal to or more than a crystallization starting temperature, and stopping the heating when heating the ribbon piece up to the intermediate position; and sequentially heating the ribbon piece from the other end to a position immediately before the intermediate position to the temperature range. In the sequentially heating the ribbon piece from the other end, the ribbon piece is heated up to the position immediately before the intermediate position after the heating is stopped in sequentially heating the ribbon piece from the one end.

A method for the production of a metal strip is provided. The method includes providing an amorphous metal strip having a first main surface and a second, opposing main surface. The first and/or the second main surface are treated with a wet-chemical etching process and/or a photochemical etching process.