Composite material manufacture by shaping individual sheets followed by consolidating the sheets

• US 4,683,018 A
• Filed: 11/20/1985
• Issued: 07/28/1987
• Est. Priority Date: 12/06/1984
• Status: Expired due to Term

• Current Assignee: Rolls-Royce PLC (Rolls-Royce Holdings Plc)
• Original Assignee: Rolls-Royce PLC (Rolls-Royce Holdings Plc)
• Inventors: Sutcliffe, David T., Barraclough, David J.
• Primary Examiner(s): Massie, Jerome
• Application Number:
  US06/799,861
• Time in Patent Office: 615 Days
• Field of Search: 156/222, 156/228, 156/288, 156/289, 156/307.4, 156/307.3, 156/245, 156/311, 156/320, 156/307.7, 156/323, 156/330, 156/290, 156/196, 264/257, 264/297.4, 264/297.8, 264/324, 264/250, 264/259, 264/258, 425/340, 425/411
• US Class Current: 156/196
• CPC Class Codes: B29C 2791/001 Shaping in several steps
• CPC Class Codes: B29C 33/68 Release sheets
• CPC Class Codes: B29C 37/0075 using release sheets
• CPC Class Codes: B29C 43/12 using bags surrounding the moulding material or using membranes contacting the moulding material
• CPC Class Codes: B29C 70/34 and shaping or impregnating by compression , i.e. combined with compressing after the lay-up operation
• 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 2063/00 Use of EP, i.e. epoxy resins or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2105/24 crosslinked or vulcanised
• CPC Class Codes: B29K 2105/243 Partially cured
• CPC Class Codes: B29K 2707/04 Carbon
• CPC Class Codes: B32B 2305/08 Reinforcements
• CPC Class Codes: B32B 2305/74 Partially cured
• CPC Class Codes: B32B 37/0007 involving treatment or provisions in order to avoid deformation or air inclusion, e.g. to improve surface quality
• CPC Class Codes: Y10T 156/1002 with permanent bending or reshaping or surface deformation of self sustaining lamina

Abstract

A composite material comprising reinforcing carbon fibres in an epoxy resin matrix is manufactured by stacking alternate layers of resin impregnated fibre and polyester release film, and compressing the stack between shaped formers at a temperature below the resin cure temperature. The layers are than separated and the release film discarded. After re-stacking, the fibre layers are autoclave moulded on an appropriately shaped former at a temperature at which the layers consolidate and the resin cures.

Claims

1. A method of manufacturing a composite materials comprising the steps of stacking a plurality of alternate layers of uncured epoxy resin impregnated fibre and thin elastic release film, raising the temperature of said stacked layers to a level insufficient to cure said resin occurs, and applying sufficient pressure to said stack by opposed correspondingly shaped formers so that said stacked layers are deformed from a planar condition and move laterally with respect to one another and are formed into the shape defined by said correspondingly shaped formers, allowing said stacked layers to cool and subsequently discontinuing said applied pressure, separating said layers of said stack and removing said thin elastic release films therefrom, restacking said partially cured resin impregnated fibre layers on a former corresponding in shape therewith and applying sufficient pressure to said layers to fully consolidate them and at such a temperature and for such a time that the final curing of said resin occurs.

2. A method of manufacturing a composite material as claimed in claim 1 wherein the temperature of said stacked layers is raised to a level at which only partial curing of said resin occurs prior to said stacked layers being formed into the shape defined by said correspondingly shaped formers.

3. A method of manufacturing a composite material as claimed in claim 1 wherein the application of said pressure to said layers in order to fully consolidate them and at such a temperature that said resin fully cures is achieved by autoclave moulding.

4. A method of maunfacturing a composite material as claimed in claim 1 wherein said fibre is carbon fibre.

5. A method of manufacturing a composite material as claimed in claim 1 wherein said thin elastic release film is formed from a polyester.

6. A method of manufacturing a composite material as claimed in claim 1 wherein said resin impregnated layers are tacked together after said re-stacking.

7. A method of manufacturing a composite material as claimed in claim 6 wherein said resin impregnated layers are tacked together by welding.