Method for making Fe-based amorphous metal powders and method for making soft magnetic core using the same

• US 20050028889A1
• Filed: 10/14/2003
• Published: 02/10/2005
• Est. Priority Date: 08/06/2003
• Status: Active Grant

• Current Assignee: Amosense Co., Ltd.
• Original Assignee: Amosense Co., Ltd.
• Inventors: Song, Yong Sul, Hong, Jae Hwa, Kim, Hie Jin
• Granted Patent: US 7,172,660 B2
• Time in Patent Office: Days
• US Class Current: 148/104
• CPC Class Codes: H01F 1/15341 Preparation processes therefor
• CPC Class Codes: H01F 1/20 in the form of particles, e.g. powder H01F1/147 takes precedence
• CPC Class Codes: H01F 41/0226 from amorphous ribbons

Abstract

A method for making an amorphous soft magnetic core using Fe-based amorphous metal powders is provided. The amorphous soft magnetic powders are obtained by crushing amorphous ribbons produced using a rapid solidification process (RSP). The magnetic core is obtained by performing a preliminary thermal treatment of amorphous metal ribbons made of Fe-based amorphous metal alloy using RSP, crushing the amorphous metal ribbons to thereby obtain amorphous metal powders, classifying the amorphous metal powders to then be mixed into a distribution of powder particles having an optimal uniform composition, mixing the mixed amorphous metal powders with a binder, forming a core, and annealing the formed core to then coat the core with an insulating resin.

Claims

1. A method of making an amorphous soft magnetic core comprising the steps of:

performing a preliminary thermal treatment of amorphous metal ribbons made of Fe-based amorphous metal alloy using a rapid solidification process;

crushing the amorphous metal ribbons to thereby obtain amorphous metal powders;

classifying the amorphous metal powders to then be mixed into a distribution of powder particles having an optimal uniform composition;

mixing the mixed amorphous metal powders with a binder, and then forming a core; and

annealing the formed core to then coat the core with an insulating resin.

2. The method of making a soft magnetic core of claim 1, wherein the amorphous metal ribbon is produced by a rapid solidification process.

3. The method of making a soft magnetic core of claim 1, wherein a distribution of powder particles is made of first powders having passed through a sieve of −

100^˜

+140 meshes of 35^˜

45%, and second powders having passed through a sieve of −

140^˜

+200 meshes of 55^˜

65%.

4. The method of making a soft magnetic core of claim 1, wherein the binder includes any one selected from the group consisting of phenol, polyimide and epoxy by 0.5 to 2 wt %.

5. The method of making a soft magnetic core of claim 1, wherein the annealing process is performed for 0.3 to 4.3 hours at a temperature of 300 to 500°

C. under the atmosphere.

6. A method of making amorphous metal powders for use in a soft magnetic core having an excellent direct-current (DC) overlapping characteristic, the method comprising the steps of:

performing a preliminary thermal treatment of Fe-based amorphous metal ribbons produced by using a rapid solidification process;

crushing the amorphous metal ribbons to thereby obtain amorphous metal powders; and

classifying the amorphous metal powders to then be mixed into a distribution of powder particles having an optimal uniform composition including powder particles made of first powders having passed through a sieve of −

100^˜

+140 meshes of 35^˜

45%, and second powders having passed through a sieve of −

140^˜

+200 meshes of 55^˜

65%.

7. The method of making amorphous metal powders of claim 6, wherein the Fe-based amorphous a metal ribbon is made of an amorphous metal alloy comprising Fe as a basic composition and at least one element selected from the group consisting of P, C, B, Si, Al and Ge as an auxiliary element.