Cosmetic repair of a thermoplastic carbon fiber composite

• US 10,589,477 B2
• Filed: 05/02/2016
• Issued: 03/17/2020
• Est. Priority Date: 05/02/2016
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Huang, Xiaosong, Zhao, Selina X., Berger, Elisabeth J., Rodgers, William R., Ryutani, Tomohiro, Novak, Glen
• Primary Examiner(s): Minskey, Jacob T
• Assistant Examiner(s): Tsui, Melody
• Application Number:
  US15/144,625
• Publication Number:
  US 20170313002A1
• Time in Patent Office: 1,415 Days
• CPC Class Codes: B29C 2035/0811 using induction
• CPC Class Codes: B29C 2035/0827 using UV radiation
• CPC Class Codes: B29C 35/0805 using electromagnetic radiation
• CPC Class Codes: B29C 70/443 and impregnating by vacuum or injection
• CPC Class Codes: B29C 70/549 Details of caul plates, e.g. materials or shape
• CPC Class Codes: B29C 73/02 using liquid or paste-like material B29C73/16 takes precedence
• CPC Class Codes: B29C 73/10 using patches sealing on the surface of the article B29C73/14 takes precedence
• CPC Class Codes: B29K 2101/12 Thermoplastic materials
• CPC Class Codes: B29K 2105/256 Sheets, plates, blanks or films

Abstract

Methods of repairing a defect in a polymeric composite structure are provided. The methods include disposing a patch over a defect in a polymeric composite structure; disposing a textured sheet over the polymeric patch, applying pressure to the polymeric patch and the textured sheet; and heating the polymeric patch. The textured sheet has a surface texture that is a negative of a surface texture of the polymeric composite structure.

Claims

1. A method of repairing a defect in a polymeric composite structure, the method comprising:

filling the defect in its entirety with a filling material, the filling material comprising a thermoplastic polymer or a thermoset polymer;

smoothing the filling material so that the filling material has a surface that is flush with the exposed surface of the polymeric composite structure;

hardening the filling material in the defect;

disposing a polymeric patch over the defect;

disposing a textured sheet over the polymeric patch, wherein the textured sheet has a first surface texture that is a negative of a second surface texture of the exposed surface of the polymeric composite structure;

applying pressure to the polymeric patch and the textured sheet;

heating the polymeric patch so that the polymeric patch softens, and

cooling the polymeric patch,

wherein the applying pressure and the heating causes the textured sheet to transfer the first surface texture to the polymeric patch, such that the polymeric patch has a third surface texture that matches the second surface texture of the polymeric composite structure, and

wherein the cooling causes the polymeric patch to adhere to the polymeric composite structure.

2. The method according to claim 1, wherein a first color of the polymeric patch is visibly the same as a second color as the polymeric composite structure.

3. The method according to claim 1, wherein the polymeric patch comprises a thermoplastic polymer and the polymeric patch has a thickness of from greater than or equal to about 1 μ

m to less than or equal to about 1 mm.

4. The method according to claim 1, wherein the polymeric patch comprises a polymeric composite having the same polymeric matrix as the polymeric composite structure and optionally the same reinforcing material as the polymeric composite structure.

5. The method according to claim 1, wherein the textured sheet is a flexible textured silicone sheet.

6. The method according to claim 5, further comprising disposing a heating element over the flexible textured silicone sheet, wherein the heating element applies heat for the heating of the polymeric patch.

7. The method according to claim 1, wherein the textured sheet is a surface of a heat blanket that contacts an exposed surface of the polymeric patch, wherein the heat blanket provides heat for the heating the polymeric patch.

8. The method according to claim 1, wherein the applying pressure to the polymeric patch and the textured sheet comprises disposing a vacuum bag over the polymeric patch and textured sheet, such that edges of the vacuum bag are sealed against the polymeric composite structure;

and drawing a vacuum through a port in communication with the vacuum bag.

9. The method according to claim 1, wherein the applying pressure to the polymeric patch and the textured sheet comprises disposing a sandbag on top of a source of heat disposed on the textured sheet and optionally applying mechanical force to the sandbag.

10. The method according to claim 1, further comprising:

disposing a heating element over the textured sheet, wherein the heating element is a heat blanket or an induction heater.

11. The method according to claim 1, wherein the heating the polymeric patch includes heating the polymeric patch to a temperature that does not exceed a temperature that is about 30°

C. higher than a melting point of the polymeric composite structure.

12. The method according to claim 1, wherein the polymeric patch and the polymeric composite structure comprise a thermoplastic polymer individually selected from the group consisting of:

polyester, polyurethane, polyolefin, poly(acrylic acid), poly(methyl acrylate), poly(methylmethacrylate), acrylonitrile butadiene styrene, polyamides, polylactic acid, polybenzimidazole, polycarbonate, polyether sulfone, polyetherether ketone, polyetherimide, polyethylene, polyphenylene oxide, polyphenylene sulfide, polypropylene, polystyrene, polyvinyl chloride, polytetrafluoroethylene, co-polymers thereof, and the polymeric composite structure further comprises a reinforcement material selected from the group consisting of;

carbon fibers, glass fibers, basalt fibers, aramid fibers, boron fibers, ceramic fibers, polyester fibers, ultra-high molecular weight polyethylene fibers, hemp fibers, and combinations thereof.

13. The method according to claim 1, wherein the defect is a structural defect that extends from the exposed surface of the polymeric composite structure to an opposing unexposed surface of the polymeric composite structure, and the method further comprises, prior to the filling:

attaching a plate to the unexposed surface of the polymeric composite structure so that the plate spans the structural defect.

14. The method according to claim 13, wherein the attaching is performed with an adhesive, with hardware, or with a combination thereof.

15. The method according to claim 13, wherein the plate comprises a metal, an alloy, steel, fiber glass, a polymer, or a polymer composite.