Joining carbon laminates using pulsed laser irradiation

Patent metadata

Field	Value
Publication number	US-11465368-B2
Application number	US-201816753542-A
Country	US
Kind code	B2
Filing date	Oct 3, 2018
Priority date	Oct 12, 2017
Publication date	Oct 11, 2022
Grant date	Oct 11, 2022

Abstract

A method for bonding two elements, the method including receiving first and second elements, the first element being a composite material; applying a laser-based treatment to a surface of the first element to obtain a treated surface; patterning the treated surface to have plural trenches; applying an adhesive to one of the first and second elements; and joining the first element to the second element so that the adhesive is between the first and second elements.

First claim

What is claimed is:

1. A method for bonding comprising:
receiving first and second elements, the first element being a composite material that includes plural fibers;
applying a laser-based treatment to a surface of the first element to obtain a treated surface, which partially exposes a set of fibers of the plural fibers without forming trenches in the surface;
patterning the treated surface using another laser-based treatment, to make plural trenches, which fully expose a subset of the set of fibers while remaining fibers of the set of fibers remain partially exposed on the treated surface, wherein the plural trenches extend along the plural fibers;
applying an adhesive to one of the first and second elements; and
joining the first element to the second element so that the adhesive is between the first and second elements,
wherein a mode I fracture toughness of the joined first and second elements is higher than a linear combination of (1) a mode I fracture toughness of the first element and (2) a mode I fracture toughness of the second element due to the laser-based treatment, the another laser-based treatment and an orientation of the plural trenches.

2. The method of claim 1 , wherein a toughness of the joined first and second elements does not follow a rule of mixture, which is a linear relation.

3. The method of claim 1 , wherein a measured toughness of the joined first and second elements is higher than a prediction of a rule of mixture, which is a linear relation.

4. The method of claim 1 , wherein the laser-based treatment comprises:
irradiating with a laser beam the surface to ablate a surface matrix and partially expose carbon fibers making up the first element.

5. The method of claim 4 , wherein a laser fluence is smaller than 10 J/cm2.

6. The method of claim 1 , wherein the patterning step comprises:
forming trenches into the surface of the first element.

7. The method of claim 6 , wherein the trenches are parallel to each other.

8. The method of claim 7 , wherein the trenches are parallel to carbon fibers making up the first element.

9. The method of claim 6 , wherein a width of a trench is in the order of micrometers and a distance between adjacent trenches is in the order of micrometers.

10. The method of claim 6 , wherein a width of the trench is the same with a distance between adjacent trenches.

11. The method of claim 6 , wherein a width of the trenches is about 250 μm.

12. The method of claim 11 , wherein a depth of the trench is about 50 μm.

13. The method of claim 1 , further comprising:
applying the laser-based treatment to a surface of the second element; and
patterning the surface of the second element to have other plural trenches.

Assignees

• Univ King Abdullah Sci & Tech
• Univ Della Calabria

Inventors

• Tao Ran
• Alfano Marco
• Lubineau Gilles

Classifications

• B23K26/402

  involving non-metallic material, e.g. isolators · CPC title

• B29C66/7212

  characterised by the composition of the fibres · CPC title

• B32B5/02

  characterised by structural features of a {fibrous or filamentary} layer {(layer formed of metallic wires B32B15/02; layer formed of natural mineral fibres B32B19/02; layer formed of wood fibres B32B21/02)} · CPC title

• B29C65/4835

  Heat curing adhesives · CPC title

• B23K26/144

  the fluid stream containing particles, e.g. powder · CPC title