Method for manufacturing alloy ribbon piece

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 ΔQself, a heat discharge amount of the amorphous alloy ribbon piece per unit time is ΔQout, 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
• ΔQself≤ΔQout+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).