Method for the resistance welding of fiber-composite components to give a fiber-composite structure, fiber-composite structure and fiber-composite component

Patent metadata

Field	Value
Publication number	US-12030258-B2
Application number	US-201816144067-A
Country	US
Kind code	B2
Filing date	Sep 27, 2018
Priority date	Sep 28, 2017
Publication date	Jul 9, 2024
Grant date	Jul 9, 2024

Abstract

A method for resistance welding of two fiber-composite components to give a fiber-composite structure includes arranging conductive fibers within a jointing region of the two fiber-composite components, where each conductive fiber includes a carbon fiber with an electrically insulating coating. An electric current is passed through the conductive fibers to heat the jointing region to a welding temperature and melt the fiber-composite components in the jointing region. The jointing region is hardened in a manner that bonds the two fiber-composite components by way of the jointing region to give the fiber-composite structure.

First claim

The invention claimed is:

1. A method for resistance welding of two fiber-composite components to give a fiber-composite structure, the method comprising:
arranging a plurality of individual conductive fibers in a form of a first layer having a first portion of the plurality of individual conductive fibers and a second layer having a second portion of the plurality of individual conductive fibers, the first layer and the second layer being within a jointing region of the two fiber-composite components, wherein:
all conductive fibers of the first portion of the plurality of individual conductive fibers extend in a first direction within the first layer;
all conductive fibers of the second portion of the plurality of individual conductive fibers extend in a second direct, the second direction being transverse to the first direction within the second layer;
the first layer is on top of the second layer, such that the conductive fibers in the first layer and the conductive fibers in the second layer form a grid;
the plurality of individual conductive fibers are arranged between the fiber-composite components;
the fiber-composite components are arranged on opposite sides of the jointing region; and
each of the plurality of individual conductive fibers comprises a carbon fiber with an electrically insulating coating;

passing an electric current through the plurality of individual conductive fibers to heat the jointing region to a welding temperature and melt the fiber-composite components in the jointing region; and
hardening the jointing region to bond the two fiber-composite components by way of the jointing region to give the fiber-composite structure.

2. The method according to claim 1 , where the fiber-composite components are placed in contact with one another at a jointing area, which is within the jointing region.

3. The method according to claim 2 , where at least a proportion of the plurality of individual conductive fibers is arranged in the jointing area between the two fiber-composite components.

4. The method according to claim 1 , comprising pressing the two fiber-composite components against one another.

5. The method according to claim 1 , where:
the conductive fibers of the first portion of the plurality of individual conductive fibers protrude from the jointing region in the first direction; and
the conductive fibers of the second portion of the plurality of individual conductive fibers protrude from the jointing region in the second direction.

6. The method according to claim 1 , comprising:
recording the welding temperature; and
regulating the electric current on the basis of the recorded welding temperature.

7. The method according to claim 6 , where:
the welding temperature is recorded by a thermographic camera; or
the welding temperature is recorded by a temperature sensor integrated into the fiber-composite components.

8. The method according to claim 1 , where the fiber-composite components each comprise a matrix of a thermoplastic and are reinforced by a plurality of carbon fibers.

9. The method according to claim 1 , where:
the fiber-composite components each comprise a matrix of a thermoplastic comprising polyetheretherketone (PEEK); and
the welding temperature is a same as or greater than a melting point of PEEK.

10. The method according to claim 1 , where the plurality of individual conductive fibers have a polymer-electrolyte coating as the electrically insulating coating.

11. The method according to claim 1 , wherein:
the conductive fibers of the first portion of the plurality of individual conductive fibers protrude from the jointing region in the first direction; and
the conductive fibers of the second portion of the plurality of individual conductive fibers protrude from the jointing region in the second direction.

12. The method according to claim 11 , comprising:
recording the welding temperature; and
regulating the electric current on the basis of the recorded welding temperature.

13. The method according to claim 12 , wherein:
the welding temperature is recorded by a thermographic camera; or
the welding temperature is recorded by a temperature sensor integrated into the fiber-composite components.

14. The method according to claim 13 , wherein:
the electrically insulating coating is a polymer-electrolyte coating formed by, for each of the plurality of individual conductive fibers, polymerization of methoxy polyethylene glycol monomethacrylate; and/or
forming the polymer-electrolyte coating comprises immersion of the carbon fiber for each of the plurality of individual conductive fibers into an electrochemical bath.

15. The method according to claim 14 , wherein:
the electrically insulating coating can withstand a temperature of at least 700° C.;
the fiber-composite components each comprise a matrix of polyetheretherketone (PEEK); and
the welding temperature is the same as or greater than a melting point of polyetheretherketone.

16. The method according to claim 15 , comprising connecting a power source to ends of the conductive fibers in the second portion of the plurality of individual conductive fibers that protrude from the jointing region in a lateral direction, wherein the electric current passes through the ends of the conductive fibers to heat the jointing region.

Assignees

• Airbus Operations Gmbh

Inventors

• Linde Peter
• Heltsch Norbert

Classifications

• B29C66/71

  characterised by the composition of the plastics material of the parts to be joined (welding bar compositions B29C65/125) · CPC title

• B29C65/4815

  Hot melt adhesives, e.g. thermoplastic adhesives · CPC title

• B29C65/3496

  with a coating, e.g. a metallic or a carbon coating · CPC title

• B29C65/344

  being a woven or non-woven fabric or being a mesh · CPC title

• B29C65/3436

  comprising independent continuous fibre-reinforcements · CPC title