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University ofAlberta
MANUFACTURING TECHNOLOGY FOR FIBRE-REINFORCED POLYMERIC
COMPOSITES (FRPC)
University ofAlberta
FRP MANUFACTURING
• General Manufacturing Objectives:- to form required shape and size - to properly ensure that the reinforcement phase is completely encapsulated by the resin phase
- to eliminate voids and entrapped air- to ensure the proper fiber direction and fiber-resin
proportion- to produce homogeneous distribution of
reinforcement phase (uniformity)
University ofAlberta
FRP MANUFACTURING
Most Common Manufacturing Methods for Fiber
Reinforced Polymeric (FRP) Composites:
- Hand Lay-up
- Spray-up
- Compression & Resin Transfer Molding (RTM)
- Pultrusion
- Filament Winding
University ofAlberta
HAND LAY-UP
Two Main Methods of Hand Lay-up:• Wet Lay-up:
- dry reinforcement (fiber mat or woven cloths) is first applied to the mold, and then is saturated with liquid resin
• Dry Lay-up: - reinforcement and resin (thermoset) are applied simultaneously as a pre-impregnated fiber tape (prepreg)- the resin in the prepreg sheets is ‘B’ staged (i.e. solidified and tacky but only partially cured)
University ofAlberta
HAND LAY-UP
Source: Wittman and Shook, Hand Lay-up Techniques in “Handbook of Composites”, (Ed. G. Lubin), Van Nostrand Reinhold, 1982
Wet Lay-up Technique
University ofAlberta
HAND LAY-UP
Wet Lay-up MethodAdvantages:
- good method for limited runs or prototyping (flexible and low capital costs)
Disadvantages: - highly manual fabrication method- quality of part is worker dependent (may not be
repeatable)
University ofAlberta
HAND LAY-UP
Example of Dry Lay-up Technique (Cylindrical Parts using Rolling Table)
Source: J. Wolodko, “Biaxial Fatigue and Leakage Characteristics of Fiber Reinforced Composite Tubes”, Ph.D. Thesis, University of Alberta, 1999
University ofAlberta
HAND LAY-UPDry Lay-up Method
• Advantages: - superior part quality and repeatability (used by aircraft industry)- method can be automated using tape placement machines (but expensive >$1M)
• Disadvantages: - requires elevated temperatures to cure the resin and
applied pressure to consolidate the part (i.e. autoclave or oven/shrink tape)
- material and storage costs are expensive
University ofAlberta
Automated Tape-Laying Equipment
University ofAlberta
SPRAY-UP
Spray-up Technique
Source: Wittman and Shook, Hand Lay-up Techniques in “Handbook of Composites”, (Ed. G. Lubin), Van Nostrand Reinhold, 1982
University ofAlberta
SPRAY-UP• Advantages:
- fast process- reinforced resin can take on any contour- can be automated
Disadvantages: - produces short fiber reinforcement (low strength
applications) - requires specialized equipment- spray area requires necessary ventilation
University ofAlberta
RESIN TRANSFER MOLDING (RTM)
• General Method: - in a two part mold, the fiber reinforcement (mat, cloth, porous foam or preforms) is stacked/placed in the mold- the mold is closed and resin and hardener are either injected or drawn (via vacuum) into the fiber reinforcement- polymer phase is cured (at room or elevated temperatures, depending on resin system used)
Preforms: Fiber network which has the general shape of the part but is still permeable to resin flow (i.e. skeleton structure) - fabricated separately by textile technologies (braiding, etc.) or spray-up (using less resin), and is used for fast production of parts.
University ofAlberta
RESIN TRANSFER MOLDING (RTM)
Source: B. Jang, “Advanced Polymer Composites: Principles and Applications”, ASM International, 1994
Schematic of RTM Process
University ofAlberta
• Advantages: - can produce complicated shapes (depends upon drapability
of reinforcement)- can produce a “near-net” shape (which does not require
any further machining) - can be a fast process (depends on pressure and
reinforcement type)- can be performed by hand or fully automated (flexible)
• Disadvantages: - requires a closed mold and injection/vacuum system- for higher processing speeds, high pressure steel molds
and equipment are required (expensive)
RESIN TRANSFER MOLDING (RTM)
University ofAlberta
Manufacturing of Textile Preform
Preforms: Fiber network which has the general shape of the part but is still permeable to resin flow (i.e. skeleton structure) - fabricated separately by textile technology such as braiding, and is used for fast production of parts.
University ofAlberta
PULTRUSION
• General Method: - dry fiber rovings (strands) are continuously pulled through a resin bath and forced through dies to form various cross-sectional shapes- often the surface is reinforced with cross-ply cloth/veils to prevent matrix cracking (splitting) along the fiber direction- polymer phase is cured continuously at elevated temperatures (specialized fast curing resins)- sections are automatically parted at required lengths (can produce long sections)
University ofAlberta
Pultrusion Process and Available Shapes
University ofAlberta
PULTRUSION• Advantages:
- produces very strong structural members (unidirectional continuous fibers) which can be used when the applied loading is known to be in the fiber direction (i.e. uniaxial or bending loads) - very fast process
• Disadvantages: - expensive and complex machinery required (extensive capital investment)- pultruded parts not very good under torsion and transverse loading (shear)
University ofAlberta
FILAMENT WINDING
• General Method: - continuously apply reinforcement and resin system on to a rotating mandrel, one band of roving at a time - the applied fiber angle is determined by the relationship between the mandrel rotation and movement of the traversing carriage- trapped air is reduced by applying tension to the fibers- polymer is cured at room or elevated temperatures depending upon process and polymer used- upon removal from mold, final trimming or machining of the part may be required
University ofAlberta
FILAMENT WINDING
Two Main Methods of Filament Winding:• Wet Winding:
- dry fiber rovings are passed through a liquid resin bath, then continuously applied to the part through a pay-out eye
• Dry Winding: - reinforcement and resin (thermoset) are applied
simultaneously as a pre-impregnated fiber tow (towpreg)- the resin in the towpreg rovings is ‘B’ staged (i.e.
solidified and tacky but only partially cured)
University ofAlberta
FILAMENT WINDING
Wet Winding Technique
Source: B. Jang, “Advanced Polymer Composites: Principles and Applications”, ASM International, 1994
University ofAlberta
FILAMENT WINDING
Dry Winding Technique
University ofAlberta
FILAMENT WINDING• Advantages:
- good method of producing shells of revolution (e.g. pipe, tubing, vessels and tanks) with very high strength (continuous fibers) - can produce parts with complex profiles along its length and irregular cross-sectional shapes (e.g. rectangular tubing)- relatively fast process (automated)
• Disadvantages: - expensive and complex machinery required (extensive capital investment)- difficult to wind angles along mandrel axis
University ofAlberta
FRP MANUFACTURING SUMMARY
Selecting a Manufacturing Method for Fiber Reinforced Polymeric (FRP) Composites:
- Hand Lay-up and Spray-up can be performed with simple equipment, and are good methods for limited production runs and prototyping.
- Automated Tape Lay-up, Rasin Transfer Molding,Pultrusion and Filament Winding require expensive equipment to produce parts, but with faster production rate and pre-fabricated products are available off the shelf (e.g. beams and tubing)
University ofAlberta
APPLICATIONS OF FRP COMPOSITESAerospace Applications:
University ofAlberta
APPLICATIONS OF FRP COMPOSITES
Evolution of Composite Material Application at Airbus
University ofAlberta
APPLICATIONS OF FRP COMPOSITES
Major Advanced Material Candidate for Airbus A380
University ofAlberta
APPLICATIONS OF FRP COMPOSITES
Optical bench for space application, made from carbon-fiber/epoxy laminates designed with a near zero coefficient of
thermal expansion
University ofAlberta
APPLICATIONS OF FRP COMPOSITES
Automotive Applications: body parts, driveshafts, springs, bumpers and CNG tanks
University ofAlberta
APPLICATIONS OF FRP COMPOSITES
Formula Raced Car with a Carbon-Fiber/Epoxy Chassis
University ofAlberta
APPLICATIONS OF FRP COMPOSITES
Chemical Processing/Petroleum: pipe, downhole tubing, storage tanks and pressure vessels
University ofAlberta
APPLICATIONS OF FRP COMPOSITES
Recreation: racquets, golf clubs, hockey sticks, fishing rods, boats and bicycles
University ofAlberta
APPLICATIONS OF FRP COMPOSITES
Construction: grating, beams, scaffolding and infrastructure repair