Laminated composite radius filler with geometric shaped filler element and method of forming the same

Patent metadata

Field	Value
Publication number	US-9359060-B2
Application number	US-201314074692-A
Country	US
Kind code	B2
Filing date	Nov 7, 2013
Priority date	Nov 7, 2013
Publication date	Jun 7, 2016
Grant date	Jun 7, 2016

Abstract

A laminated composite radius filler for a composite structure has a stacked ply assembly having a plurality of stacks of laminate radius filler plies cut to a desired width and having a desired ply orientation. The laminated composite radius filler further has a geometric shaped filler element positioned at a desired location on a first portion of the stacked ply assembly. The geometric shaped filler element deforms a second portion of the stacked ply assembly stacked over the geometric shaped filler element, such that the laminate radius filler plies of the second portion of the stacked ply assembly change direction and have a component of direction including a horizontal direction and a vertical direction. The laminated composite radius filler having a shape substantially corresponding to a radius filler region of the composite structure.

First claim

What is claimed is:

1. A laminated composite radius filler for a composite structure comprising:
a stacked ply assembly comprising a plurality of stacks of laminate radius filler plies cut to a desired width and having a desired ply orientation; and,
a separate, pre-formed geometric shaped filler element comprising a plurality of plies comprised of a plurality of unidirectional fibers, a unidirectional fiber tape, a prepreg unidirectional tape, a unidirectional composite tow, a slit unidirectional tape, a carbon fiber-reinforced plastic (CFRP) tape, a carbon fiber-reinforced plastic (CFRP) fabric, a prepreg fabric, a woven fabric including a woven carbon fiber fabric, or a combination thereof, the geometric shaped filler element positioned within the laminated composite radius filler at a desired location on a first portion of the stacked ply assembly, the geometric shaped filler element deforming a second portion of the stacked ply assembly stacked over the geometric shaped filler element, such that the laminate radius filler plies of the second portion of the stacked ply assembly change direction and have a component of direction comprising a horizontal direction and a vertical direction, the laminated composite radius filler having a shape substantially corresponding to a radius filler region of the composite structure and filling the radius filler region.

2. The laminated composite radius filler of claim 1 further comprising a tip element positioned on a top portion of the stacked ply assembly, the tip element comprising a plurality of unidirectional fibers, a unidirectional fiber tape, a prepreg unidirectional tape, a unidirectional composite tow, a slit unidirectional tape, a carbon fiber-reinforced plastic (CFRP) tape, a carbon fiber-reinforced plastic (CFRP) fabric, a prepreg fabric, a woven fabric including a woven carbon fiber fabric, chopped fiber, or a combination thereof.

3. The laminated composite radius filler of claim 1 further comprising one or more additional geometric shaped filler elements, each positioned at a desired location on one or more additional portions of the stacked ply assembly, and each of the one or more additional geometric shaped filler elements further deforming one or more respective additional portions of the stacked ply assembly stacked over the respective one or more geometric shaped filler elements.

4. The laminated composite radius filler of claim 1 wherein the geometric shaped filler element comprises chopped fiber.

5. The laminated composite radius filler of claim 1 wherein the geometric shaped filler element is comprised of pultruded unidirectional fibers having a zero degree (0°) ply orientation.

6. The laminated composite radius filler of claim 1 wherein the geometric shaped filler element has a geometric shape comprising one of a triangle shape, a triangle with curved corners shape, an arrowhead shape, a triangle with corners removed shape, a triangle with one or more curved sides shape, a radius filler shape, and a half circle shape.

7. The laminated composite radius filler of claim 1 wherein changing the direction of the laminate radius filler plies of the second portion minimizes a difference in coefficient of thermal expansion (CTE) and interlaminar tension stress between the laminated composite radius filler and a plurality of wrap plies adjacent the laminated composite radius filler.

8. The laminated composite radius filler of claim 1 wherein the geometric shaped filler element is positioned in an upper one-half portion of the laminated composite radius filler.

9. An aircraft composite assembly comprising:
a composite structure comprising a radius filler region and a plurality of wrap plies adjacent the radius filler region; and,
a laminated composite radius filler having a shape substantially corresponding to the radius filler region and filling the radius filler region, the laminated composite radius filler comprising:
a stacked ply assembly comprising a plurality of stacks of laminate radius filler plies cut to a desired width and having a desired ply orientation; and,
a separate, pre-formed geometric shaped filler element comprising a plurality of plies comprised of a plurality of unidirectional fibers, a unidirectional fiber tape, a prepreg unidirectional tape, a unidirectional composite tow, a slit unidirectional tape, a carbon fiber-reinforced plastic (CFRP) tape, a carbon fiber-reinforced plastic (CFRP) fabric, a prepreg fabric, a woven fabric including a woven carbon fiber fabric, or a combination thereof, the geometric shaped filler element positioned within the laminated composite radius filler at a desired location on a first portion of the stacked ply assembly, the geometric shaped filler element deforming a second portion of the stacked ply assembly stacked over the geometric shaped filler element, such that the laminate radius filler plies of the second portion of the stacked ply assembly change direction and have a component of direction comprising a horizontal direction and a vertical direction.

10. The aircraft composite assembly of claim 9 wherein the laminated composite radius filler further comprises a tip element positioned on a top portion of the stacked ply assembly, the tip element comprising a plurality of unidirectional fibers, a unidirectional fiber tape, a prepreg unidirectional tape, a unidirectional composite tow, a slit unidirectional tape, a carbon fiber-reinforced plastic (CFRP) tape, a carbon fiber-reinforced plastic (CFRP) fabric, a prepreg fabric, a woven fabric including a woven carbon fiber fabric, chopped fiber, or a combination thereof.

11. The aircraft composite assembly of claim 9 wherein the laminated composite radius filler further comprises one or more additional geometric shaped filler elements, each positioned at a desired location on one or more additional portions of the stacked ply assembly, and each of the one or more additional geometric shaped filler elements further deforming one or more respective additional portions of the stacked ply assembly stacked over the respective one or more geometric shaped filler elements.

12. The aircraft composite assembly of claim 9 wherein the geometric shaped filler element comprises chopped fiber.

13. The aircraft composite assembly of claim 9 wherein the geometric shaped filler element has a geometric shape comprising one of a triangle shape, a triangle with curved corners shape, an arrowhead shape, a triangle with corners removed shape, a triangle with one or more curved sides shape, a radius filler shape, and a half circle shape.

14. The aircraft composite assembly of claim 9 wherein changing the direction of the laminate radius filler plies of the second portion minimizes a difference in coefficient of thermal expansion (CTE) and interlaminar tension stress between the laminated composite radius filler and the plurality of wrap plies adjacent the laminated composite radius filler, resulting in elimination of delamination or a reduced delamination in the laminated composite radius filler.

15. A laminated composite radius filler for a composite structure comprising:
a stacked ply assembly comprising a plurality of stacks of laminate radius filler plies cut to a desired width and having a desired ply orientation; and,
a separate, pre-formed geometric shaped filler element comprising a plurality of plies comprised of a plurality of unidirectional fibers, a unidirectional fiber tape, a prepreg unidirectional tape, a unidirectional composite tow, a slit unidirectional tape, a carbon fiber-reinforced plastic (CFRP) tape, a carbon fiber-reinforced plastic (CFRP) fabric, a prepreg

Assignees

• Boeing Co

Inventors

• Kajita Kirk B
• Frisch Douglas A

Classifications

• Y10T428/24314

  Slit or elongated · CPC title

• Y10T156/1002

  with permanent bending or reshaping or surface deformation of self sustaining lamina · CPC title

• B29L2031/3082

  Fuselages · CPC title

• B32B3/266 Primary

  characterised by an apertured layer, the apertures going through the whole thickness of the layer, e.g. expanded metal, perforated layer, slit layer regular cells B32B3/12 · CPC title

• B29C70/34 Primary

  and shaping or impregnating by compression {, i.e. combined with compressing after the lay-up operation} · CPC title