Three-dimensional spacer fabric resin interlaminar infusion media process and vacuum-induced reinforcing composite laminate structures

• US 20030102604A1
• Filed: 01/03/2003
• Published: 06/05/2003
• Est. Priority Date: 07/23/2001
• Status: Active Grant

• Current Assignee: VRAC LLC
• Original Assignee: VRAC LLC
• Inventors: Smith, Mitchell D., Mack, Patrick E.
• Granted Patent: US 7,060,156 B2
• Time in Patent Office: Days
• US Class Current: 264/511
• CPC Class Codes: B29C 70/24 oriented in at least three directions forming a three dimensional structure
• CPC Class Codes: B29C 70/443 and impregnating by vacuum or injection
• CPC Class Codes: B29C 70/48 and impregnating the reinforcements in the closed mould, e.g. resin transfer moulding [RTM] , e.g. by vacuum
• CPC Class Codes: B29C 70/547 using channels or porous distribution layers incorporated in or associated with the product
• CPC Class Codes: B32B 2305/08 Reinforcements
• CPC Class Codes: B32B 27/04 as impregnant, bonding, or embedding substance not used
• CPC Class Codes: B32B 38/1866 conforming the layers or laminate to a convex or concave profile
• CPC Class Codes: B32B 5/08 the fibres or filaments of a layer being of different substances , e.g. conjugate fibres, mixture of different fibres
• CPC Class Codes: D04B 21/16 incorporating synthetic threads
• CPC Class Codes: D10B 2403/021 Lofty fabric with equidistantly spaced front and back plies, e.g. spacer fabrics
• CPC Class Codes: D10B 2505/02 Reinforcing materials; Prepregs
• CPC Class Codes: Y10T 428/24107 including mechanically interengaged strands, strand-portions or strand-like strips

Abstract

A three-dimensional spacer fabric resin interlaminar infusion medium and reinforcing composite lamina for use in the vacuum-induced manufacture of fiber reinforced polymer composites is described. This use of the three-dimensional spacer fabric as a composite interlaminar component improves both the vacuum-induced resin infusion flow rate and laminate quality control and aids in the achievement of enhanced resin uniformity distribution throughout the laminate.

Claims

1. A method for the vacuum-induced fabrication of reinforced plastic composites comprising assembling a fiber structure including

a three-dimensional fibrous spacer fabric employed as an interlamina infusion medium,

said fabric having at least first and second outer substantially fibrous layer surfaces composed of woven or non-woven fibers or yams,

said fiber layers being generally oriented in an X-Y plane,

and having therebetween an intermediate spacer fiber layer composed of resilient spacer fibers or yams oriented in a generally transverse Z direction with respect to said X-Y plane of said outer layers,

juxtapositioning said spacer fabric with respect to at least one mold surface of a desired shape and configuration,

forming an assembly of substantially gas impervious cover sheet substantially enclosing said fabric and mold surface,

applying a negative pressure to said assembly, while also

introducing a liquid resin flow within and into said intermediate spacer fiber layer,

continuing said resin flow so as to substantially fully permeate said interlamina spacer fabric including said outer surfaces,

terminating the resin flow and the application of negative pressure,

and thereafter allowing the resin content of the resulting fiber reinforced composite to cure.

2. The method of claim 1 wherein said interlamina spacer fabric is also provided with at least one additional fibrous layer on at least one of said outer surfaces.

3. The method of claim 1 wherein said interlamina spacer fabric is also provided with at least one additional fibrous layer on each of said outer surfaces.

4. The method of claim 2 wherein said interlamina spacer fabric and said one additional fibrous layer are assembled together by stitching or knitting the same.

5. The method of claim 3 wherein said interlamina spacer fabric and said additional fibrous layers are assembled together by stitching or knitting the same.

6. The method of any one of claims 1, 2, 3, 4, or 5 wherein said interlamina spacer fabric has an initial thickness of from about 2 mm to about 25 mm.

7. The method of claim 1 wherein application of negative pressure initially causes the said Z-directional spacer fibers to collapse, and the termination of negative pressure subsequently induces the said Z-directional spacer fibers to spring back but thereafter to at least partially re-collapse under ambient atmospheric pressure whereby a consolidated composite interlamina spacer fabric structure is obtained.

8. The method of claim 7 wherein said interlamina spacer fabric is also provided with at least one additional fibrous layer on at least one of said outer surfaces.

9. The method of claim 7 wherein said interlamina spacer fabric is also provided with at least one additional fibrous layer on each of said outer surfaces.

10. The method of claim 8 wherein said interlamina spacer fabric and said additional fibrous layer are assembled together by stitching or knitting the same.

11. The method of claim 9 wherein said interlamina spacer fabric and said additional fibrous layer are assembled together by stitching or knitting the same.

12. The method of any one of claims 7, 8, 9, 10 or 11 wherein said interlamina spacer fabric has an initial thickness of from about 2 mm to about 25 mm.

13. The method of any one of claims 1 or 7 wherein said interlamina spacer fabric has said outer fibrous layers are at least in part independently composed of polyester, polyolefin, glass or carbon fibers, or mixtures thereof.

14. The method of any one of claims 1 or 7 wherein the said Z-directional resilient spacer fibers are at least in part composed of polyester, polyolefin, or glass fibers, or mixtures thereof.

15. The method of claims 2 or 3 wherein said additional fibrous layers are independently composed of polyester, polyolefin, glass or carbon fibers, or mixtures thereof.

16. The method of claims 8 or 9 wherein said additional fibrous layers are independently composed of polyester, polyolefin, glass or carbon fibers, or mixtures thereof.

17. A vacuum-infused product as produced by the process of any of claims 1, 2, 3, 4, 6, 7, 8, 9, 10 or 11.