Composite detail having Z-pin stubble

• US 5,863,635 A
• Filed: 03/07/1997
• Issued: 01/26/1999
• Est. Priority Date: 05/31/1996
• Status: Expired due to Term

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Childress, James J.
• Primary Examiner(s): Ahmad, Nasser
• Application Number:
  US08/812,639
• Time in Patent Office: 690 Days
• Field of Search: 428/119, 428/120, 428/102, 428/113, 52/309.7, 52/309.9, 52/309.11
• US Class Current: 428/119
• CPC Class Codes: B29C 2035/0811 using induction
• CPC Class Codes: B29C 2035/0816 using eddy currents
• CPC Class Codes: B29C 65/344 being a woven or non-woven fabric or being a mesh
• CPC Class Codes: B29C 65/3476 being metallic
• CPC Class Codes: B29C 65/364 being a woven or non-woven fabric or being a mesh
• CPC Class Codes: B29C 65/3644 being a ribbon, band or strip
• CPC Class Codes: B29C 65/3676 being metallic
• CPC Class Codes: B29C 65/4815 Hot melt adhesives, e.g. thermoplastic adhesives
• CPC Class Codes: B29C 65/483 Reactive adhesives, e.g. chemically curing adhesives
• CPC Class Codes: B29C 65/5057 positioned between the surfaces to be joined B29C65/5035 takes precedence
• CPC Class Codes: B29C 65/564 hidden in the joint, e.g. dowels or Z-pins B29C65/603 takes precedence
• CPC Class Codes: B29C 65/76 Making non-permanent or releasable joints
• CPC Class Codes: B29C 66/1122 Single lap to lap joints, i.e. overlap joints B29C66/45, B29C66/472, B29C66/52272 take precedence
• CPC Class Codes: B29C 66/3034 making use of additional elements, e.g. meshes
• CPC Class Codes: B29C 66/43441 with two right angles, e.g. for making T-shaped pieces, H-shaped pieces
• CPC Class Codes: B29C 66/472 said single elements being substantially flat
• CPC Class Codes: B29C 66/474 said single elements being substantially non-flat
• CPC Class Codes: B29C 66/524 Joining profiled elements
• CPC Class Codes: B29C 66/71 characterised by the composition of the plastics material of the parts to be joined welding bar compositions B29C65/125
• CPC Class Codes: B29C 66/721 Fibre-reinforced materials B29C66/729 takes precedence
• CPC Class Codes: B29C 66/7212 : characterised by the composition of the fibres
• CPC Class Codes: B29C 66/72525 : comprising honeycomb cores
• CPC Class Codes: B29C 66/727 : being porous, e.g. foam
• CPC Class Codes: B29C 66/7392 : characterised by the material of at least one of the parts being a thermoplastic
• CPC Class Codes: B29C 66/7394 : characterised by the material of at least one of the parts being a thermoset
• CPC Class Codes: B29C 66/8122 : characterised by the composition of the material constituting the pressing elements, e.g. constituting the welding jaws or clamps
• CPC Class Codes: B29C 66/81455 : being a fluid inflatable bag or bladder, a diaphragm or a vacuum bag for applying isostatic pressure inflatable element positioned between the joining tool and a backing-up part B29C66/82421
• CPC Class Codes: B29C 66/81821 : of the welding jaws
• CPC Class Codes: B29C 66/8322 : Joining or pressing tools reciprocating along one axis
• CPC Class Codes: B29C 70/24 : oriented in at least three directions forming a three dimensional structure
• CPC Class Codes: B29C 70/44 : using isostatic pressure, e.g. pressure difference-moulding, vacuum bag-moulding, autoclave-moulding or expanding rubber-moulding
• CPC Class Codes: B29K 2025/06 : PS, i.e. polystyrene
• CPC Class Codes: B29K 2063/00 : Use of EP, i.e. epoxy resins or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2079/08 : PI, i.e. polyimides or derivatives thereof
• CPC Class Codes: B29K 2079/085 : Thermoplastic polyimides, e.g. polyesterimides, PEI, i.e. polyetherimides, or polyamideimides; Derivatives thereof
• CPC Class Codes: B29K 2307/04 : Carbon
• CPC Class Codes: B29K 2309/08 : Glass
• CPC Class Codes: B29K 2909/02 : Ceramics
• CPC Class Codes: B32B 2266/0228 : Aromatic vinyl resin, e.g. styrenic (co)polymers
• CPC Class Codes: B32B 2305/08 : Reinforcements
• CPC Class Codes: B32B 27/065 : of foam
• CPC Class Codes: B32B 27/08 : of synthetic resin
• CPC Class Codes: B32B 27/18 : characterised by the use of special additives
• CPC Class Codes: B32B 27/322 : comprising halogenated polyolefins, e.g. PTFE
• CPC Class Codes: B32B 5/18 : characterised by features of a layer of foamed material
• CPC Class Codes: B32B 7/04 : Interconnection of layers
• CPC Class Codes: B32B 7/06 : permitting easy separation
• CPC Class Codes: B32B 7/08 : by mechanical means
• CPC Class Codes: B64C 3/26 : Construction, shape, or attachment of separate skins, e.g. panels
• CPC Class Codes: Y02T 50/40 : Weight reduction
• CPC Class Codes: Y10T 428/24033 : including stitching and discrete fastener[s], coating or bond
• CPC Class Codes: Y10T 428/24124 : Fibers
• CPC Class Codes: Y10T 428/24174 : including sheet or component perpendicular to plane of web or sheet
• CPC Class Codes: Y10T 428/24182 : Inward from edge of web or sheet
• CPC Class Codes: Y10T 428/249923 : Including interlaminar mechanical fastener

Abstract

I improve the impact shock resistance of bonds between composite elements by including Z-pin reinforcement. I prepare stubbled composite structure by using peel plys over the appropriate surface of the composite during pin insertion using conventional processes. I then use the stubbled composite structure with padups, as necessary, to produce the Z-pin reinforced joint or bond between composite elements using any of adhesive bonding, cocuring, or thermoplastic welding.

Claims

1. A prefabricated aerospace composite detail part, comprising:

(a) cured and consolidated, fiber-reinforced organic matrix resin aerospace composite structure;

(b) Z-pin fiber reinforcement protruding from at least a portion of the resin composite to define a bond line to provide stubble;

areal density of said Z-pin reinforcement is between about 0.375 and 150% and

(c) an uncured resin padup covering and protecting the stubble.

2. The detail part of claim 1 further comprising a compressible foam core backing the composite.

3. The detail part of claim 1 wherein the stubble defines a strip along the composite.

4. The detail part of claim 1 wherein the Z-pin reinforcement is in an interlaced arrangement.

5. The detail part of claim 2 wherein the foam is polyimide or polystyrene.

6. The detail part of claim 1 wherein the Z-pin reinforcement has a Young'"'"'s modulus of elasticity of at least about 10⁷.

7. The detail part of claim 1 wherein the padup includes a susceptor heatable by magnetic induction.

8. The detail part of claim 1 wherein the areal density of Z-pin reinforcement differs in different areas of the stubble.