Method for manufacturing alloy ribbon piece

Patent metadata

Field	Value
Publication number	US-11535906-B2
Application number	US-202016872892-A
Country	US
Kind code	B2
Filing date	May 12, 2020
Priority date	Jun 6, 2019
Publication date	Dec 27, 2022
Grant date	Dec 27, 2022

Abstract

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 ΔQself≤ΔQout+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 ΔQself, ΔQout, m, c, and ΔT, respectively.

First claim

What is claimed is:

1. A method for manufacturing an alloy ribbon piece obtained by crystallizing an amorphous alloy ribbon piece, the method comprising:
preparing an amorphous alloy ribbon piece;
disposing the amorphous alloy ribbon piece inside a heating furnace;
heating the amorphous alloy ribbon piece that is disposed inside the furnace to a crystallization starting temperature; and
upon reaching the crystallization starting temperature, 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 by increasing the temperature inside the heating furnace,
wherein 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 a formula (1) below where a self-heating amount of the amorphous alloy ribbon piece per unit time is ΔQ self , a heat discharge amount of the amorphous alloy ribbon piece per unit time is ΔQ out , a mass and a specific heat of the amorphous alloy ribbon piece are m and c, respectively, and a temperature increase width of the amorphous alloy ribbon piece per unit time is ΔT
Δ Q self ≤ΔQ out +mcΔT   (1),

wherein a plurality of the amorphous alloy ribbon pieces are prepared in the preparing,
wherein the heating of the amorphous alloy ribbon piece to the crystallization starting temperature increases the temperature of the plurality of amorphous alloy ribbon pieces to the crystallization starting temperature, and
wherein the increasing of the temperature of the amorphous alloy ribbon piece from the crystallization starting temperature to the crystallization process termination temperature increases the temperature of the plurality of amorphous alloy ribbon pieces from the crystallization starting temperature to the crystallization process termination temperature in a state where clearances are provided between the adjacent amorphous alloy ribbon pieces such that the temperature increase rates of the plurality of amorphous alloy ribbon pieces each satisfy the formula (1).

2. The method for manufacturing the alloy ribbon piece according to claim 1 ,
wherein a material of the amorphous alloy ribbon piece is a Fe-based amorphous alloy, and
wherein an average 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 is in a range of 0.5° C./second or more and 20° C./second or less.

Assignees

• Toyota Motor Co Ltd

Inventors

• Yamashita Osamu
• Hiramatsu Shinichi

Classifications

• C21D2201/03

  Amorphous or microcrystalline structure · CPC title

• C21D1/78 Primary

  Combined heat-treatments not provided for above · CPC title

• C21D8/0247 Primary

  characterised by the heat treatment · CPC title

• C21D9/00

  Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor · CPC title

• H01F41/0226

  from amorphous ribbons · CPC title