Conductive pre-impregnated composite sheet and method for making the same

1. A method for making a conductive pre-impregnated composite sheet, said method comprising:

joining a nanomaterial composite sheet, a fiber-reinforcing sheet, and a resin film to form a combined sheet in which said nanomaterial composite sheet is located between said resin film and said fiber-reinforcing sheet, wherein:

said nanomaterial composite sheet is electrically conductive along at least one axial direction and comprises:

a nonwoven carbon fiber veil having a first surface and a second surface, opposite said first surface;

a conductive nanomaterial structure directly coupled to said first surface of said nonwoven carbon fiber veil, said conductive nanomaterial structure being opaque to a first electromagnetic radiation having a frequency greater than 100 MHz; and

a metallic coating directly coupled to said second surface of said nonwoven carbon fiber veil, said metallic coating being opaque to a second electromagnetic radiation having a frequency less than 100 MHz;

heating said combined sheet;

compacting said combined sheet;

cooling said combined sheet; and

forming said conductive pre-impregnated composite sheet.

2. The method of claim 1 wherein:

said conductive nanomaterial structure comprises a nonwoven mat of conductive nanomaterials; and

said nonwoven mat of said conductive nanomaterials is bonded to said first surface of said nonwoven carbon fiber veil.

3. The method of claim 1 wherein said conductive nanomaterial structure comprises conductive nanomaterials deposited on said first surface of said nonwoven carbon fiber veil.

4. The method of claim 1 wherein heating said combined sheet comprises passing said combined sheet over a heat plate.

5. The method of claim 4 wherein said heat plate comprises an operating temperature of between approximately 200° F. and approximately 300° F.

6. The method of claim 1 wherein cooling said combined sheet comprises passing said combined sheet over a cold plate.

7. The method of claim 6 wherein said cold plate comprises an operating temperature of between approximately 55° F. and 60° F.

8. The method of claim 1 wherein joining said nanomaterial composite sheet, said fiber-reinforcing sheet, and said resin film comprises passing said nanomaterial composite sheet, said fiber-reinforcing sheet, and said resin film through a pair of joining rollers.

9. The method of claim 8 wherein a distance between said pair of joining rollers is between approximately 16 mils and approximately 18 mils.

10. The method of claim 1 wherein compacting said combined sheet comprises passing said combined sheet through a series of pairs of compacting rollers.

11. The method of claim 10 wherein a distance between each successive one of said series of pairs of compacting rollers is decreased by approximately 0.5 mil.

12. The method of claim 1 wherein compacting said combined sheet comprises:

passing said combined sheet through a first pair of compacting rollers;

passing said combined sheet through a second pair of compacting rollers; and

passing said combined sheet through a third pair of compacting rollers.

13. The method of claim 12 wherein:

a distance between said first pair of compacting rollers is between approximately 16 mils and approximately 17 mils,

a distance between said second pair of compacting rollers is between approximately 15.5 mils and approximately 16.5 mils, and

a distance between said third pair of compacting rollers is between approximately 15 mils and approximately 16 mils.

14. The method of claim 1 wherein said fiber-reinforcing sheet is pre-impregnated with a matrix material.

15. The method of claim 1 wherein said conductive nanomaterial structure comprises at least one of carbon nanomaterials and boron nanomaterials.

16. The method of claim 1 wherein:

said nonwoven carbon fiber veil has a thickness dimension defined along a first axial direction; and

at least a portion of said conductive nanomaterial structure penetrates said conductive nonwoven veil along said first axial direction.

17. The method of claim 1 wherein said metallic coating comprises nickel.

18. The method of claim 1 further comprising:

joining said nanomaterial composite sheet, said fiber-reinforcing sheet, said resin film, and another resin film to form said combined sheet in which said nanomaterial composite sheet is located between said resin film and said another resin film, and said another resin film is located between said nanomaterial composite sheet and said fiber-reinforcing sheet.

19. The method of claim 1 wherein said metallic coating is located between said nonwoven carbon fiber veil and said resin film when joining said nanomaterial composite sheet, said fiber-reinforcing sheet, and said resin film to form said combined sheet.