COMPOSITE MAGNETIC SHEET AND PRODUCTION METHOD THEREOF

Abstract

The present invention provides a composite magnetic sheet having a high magnetic permeability, to be produced easily at a low cost. The composite magnetic sheet includes magnetic substance powders and polytetrafluoroethylene powders.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are schematic cross-sectional views of a composite magnetic sheet according to an embodiment of the present invention;

FIG. 2 is a schematic configuration diagram of a composite magnetic sheet production apparatus to be used for a part of a production process for a composite magnetic sheet according to an embodiment of the present invention;

FIG. 3 is a flowchart showing a production process for a composite magnetic sheet according to an embodiment of the present invention;

FIG. 4 is a flowchart showing a production process for a composite magnetic sheet according to another embodiment of the present invention; and

FIG. 5 is a flowchart showing a production process for a conventional composite magnetic sheet used in the comparative examples.

Claims

1. A composite magnetic sheet comprising: magnetic substance powders; andpolytetrafluoroethylene powders.

2. The composite magnetic sheet according to claim 1, wherein the magnetic substance powders are magnetic substance powders of an iron based alloy.

3. The composite magnetic sheet according to claim 1, wherein the magnetic substance powders are spherical powders.

4. The composite magnetic sheet according to claim 2, wherein the magnetic substance powders are spherical powders.

5. The composite magnetic sheet according to claim 1, wherein the magnetic substance powders are flat powders.

6. The composite magnetic sheet according to claim 2, wherein the magnetic substance powders are flat powders.

7. The composite magnetic sheet according to claim 1, wherein the composite metal sheet comprises 85% by weight or more magnetic substance powders.

8. The composite magnetic sheet according to claim 2, wherein the composite metal sheet comprises 85% by weight or more magnetic substance powders.

9. The composite magnetic sheet according to claim 1, wherein the density of the composite magnetic sheet is 3.5 g/cm3 or more.

10. The composite magnetic sheet according to claim 2, wherein the density of the composite magnetic sheet is 3.5 g/cm3 or more.

11. A production method for a composite magnetic sheet, comprising: a powder mixing process comprising mixing magnetic substance powders and polytetrafluoroethylene powders; anda pressure shaping process comprising shaping the mixed powder after the powder mixing process by pressuring.

12. The production method for a composite magnetic sheet of claim 11, further comprising: a re-pressure shaping process comprising pressuring again the composite magnetic sheet after the pressure shaping process.

13. The production method of a composite magnetic sheet according to claim 11, wherein the pressure shaping process is performed by a first roller and a second roller.

14. The production method of a composite magnetic sheet according to claim 12, wherein the pressure shaping process is performed by a first roller and a second roller.

15. The production method of a composite magnetic sheet according to claim 14, wherein the rotational rate of the first roller is different from the rotational rate of the second roller.