Claims
- 1. A manufacturing process of a magnetic core comprising the steps of:
- (a) producing an amorphous metal ribbon having the composition formula:
- (Co.sub.1-a-b-c Fe.sub.a Mn.sub.b Mo.sub.c).sub.100-x-y Si.sub.x B.sub.y (in atomic %)
- wherein a, b, c, x and y are numbers which respectively satisfy relations 0.ltoreq.a.ltoreq.0.05, 0.03.ltoreq.b.ltoreq.0.08, 0.01.ltoreq.c.ltoreq.0.04, 0.04.ltoreq.b+c.ltoreq.0.10, 14.ltoreq.x.ltoreq.16 and 7.5.ltoreq.y.ltoreq.9.5, by a rapid quenching of the molten metal on a rotating chill surface;
- (b) winding a predetermined length of the amorphous metal ribbon into a toroidal shape of core;
- (c) keeping the core at a temperature above the alloy's Curie temperature (Tc) of the alloy;
- (d) slowly cooling the core through the Curie temperature (Tc) in a DC or AC magnetic field, the direction of which is generally coincidental with the direction of the magnetic path in the core, where the cooling rate is a value of 0.1.degree. C./minute to 50.degree. C./minute;
- (e) keeping the core at least one time at a temperature between 0.95.times.Tc and 150.degree. C. for one hour to ten hours in a magnetic field, the direction of which is generally coincidental with the direction of the magnetic path in the core; and
- (f) cooling the core to a room temperature.
- 2. A manufacturing process of a magnetic core according to claim 1, wherein the step (e) in the process comprises a multi-stage heat-treatment for the core which is characterized in that the core is kept at subsequently lower temperatures between 0.95.times.Tc and 150.degree. C. for a time of one hour to ten hours in a magnetic filed, the direction of which is generally concidental with the direction of the magnetic path in the core.
- 3. A manufacturng process of a magnetic core according to claim 2, wherein the multi-stage heat-treatment for the core is characterized in that the core is kept at a subsequently lower temperatures beteen 0.95.times.Tc and 150.degree. C. for a time of one hour to ten hours which is longer as the temperature is lower, in a magnetic field, the direction of which is generally coincidental with the direciton of the magnetic path in the core.
Priority Claims (2)
Number |
Date |
Country |
Kind |
60-182330 |
Aug 1985 |
JPX |
|
60-208328 |
Sep 1985 |
JPX |
|
Parent Case Info
This is a division of application Ser. No. 898,309 filed 8/20/86 and now abandoned.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
4081298 |
Mendelsohn et al. |
Mar 1978 |
|
4249969 |
De Cristofaro et al. |
Feb 1981 |
|
4379004 |
Makino et al. |
Apr 1983 |
|
Divisions (1)
|
Number |
Date |
Country |
Parent |
898309 |
Aug 1986 |
|