Transcript Composite Materials & Polymer Matrix Composites Processes

Blade with Shear Web bonded to
Spar Cap
Upper (LP)
Spar Cap
Sandwich Shell
Sandwich Shell
Trailing Edge
Leading Edge
TE Shear
Web
Sandwich Shell
LE Shear
Web
Sandwich Shell
Lower (HP) Spar Cap
2
Source:http://www.compositesworld.com/articles/wind-blade-manufacturing-targeting-cost-efficiencythrough-materials-based-strategies.aspx 4/5/2009
Blade Objectives
Figure from GE
Blade Objectives
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•
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Maximize annual energy yield
(limit maximum power)
Resist extreme and fatigue loads
Restrict tip deflections
Avoid resonances
Minimize weight and cost
Burton, Sharpe, Jenkins, Bossanyi: “Wind Energy Handbook”
UTS
UCS
UCS/sg
Fatique %
of UCS
Stiffness/
sg
E/UCS^2
880
720
390
19
20
.07
Glass/poly 700
ester
580
310
21
18
.1
Carbon/e
poxy
1830
1100
700
32
90
.12
Birch/epo
xy
117
81
121
20
22
2.3
Glass/X
Steel: fatigue and mfgblty
Blade Materials
• compressive strength-to-weight ratio,
• fatigue strength as a percentage of
compressive strength,
• stiffness-to-weight ratio,
• a panel stability parameter, E/(UCS)2.
April 9, 2015
Courtesy: Nolet, TPI
8
Power, Length and Weight
Burton, Sharpe, Jenkins, Bossanyi: “Wind Energy Handbook”
Polymer Matrix Composites & Processes
General Composite Information
• Composites: 2 or more physically distinct
phases
• Properties are better than the constituents
• High strength to weight ratio
• Also. . Corrosion, fatigue, toughness, surface
finish
Why nots . . .
• (many have) anisotropic properties
• Polymer based may be subject to chemical
attack
• Cost?
• Manufacturing process often slow and costly
(Groover p 177)
2 or more phases
• Matrix (primary phase)
– Polymer, metal, or ceramic
• Reinforcing agent (imbedded phase)
– Polymer, metal, ceramic, or element
– Fibers, particles, . . .
Possible combinations for 2 phases
Reinforcement
Matrix
Metal
Ceramic
Polymer
Metal
PM infiltrate
w/ 2nd metal
n/a
Steel belted
tire
Ceramic
Cutting tool
SiC in Al2O3
‘fiberglass’
Polymer
PM part w/
polymer
n/a
Kevlar
reinforced
epoxy
Element
Fiber
reinforced
metals
n/a
Carbon fiber
reinforced
polymer
Fiber reinforcement
• Diameters of 0.0001 to 0.005 inches
• As D ↓, orientation ↑, probability of defect↓
– tensile strength↑ ↑
• Orientation:
– Unidirectional, planar, 3 dimensional
Fiber Reinforced Polymer Composites
• Short fibers:
– Open mold: spray up
– Closed mold processes
• Long fibers:
– Open mold: hand, automated tape machines
– Closed mold
– Filament winding
– Pultrusion
Materials
• Polymer matrix
– Thermosets: most common
– Thermoplastics
• Reinforcing
– Glass
– Carbon
– Kevlar (polymer)
Composing Composites . . .
• Molding compounds
– Mix short fibers and matrix
• Prepegs
– Fibers impregnated with partially cured TS matrix
– Allows fibers to ‘stay put’
– Continuous fibers
• Or done in the mold
Open Mold Process
• Spray up
– Requires mold
– Discontinuous fibers // random orientation
– Mixture of fiber and matrix deposited in mold
• Automated tape laying machine
– Requires mold
– Requires use of prepeg
– CNC control
Image sources: http://www.bauteck.com/manufacture/Manufacture2.htm 4/5/9
http://www.mmsonline.com/articles/getting-to-know-black-aluminum.aspx 4/5/9
Filament Winding
• Wound around mandrel or part of final
component
• Continuous fibers
– Matrix added before or after winding
• Automation controls wrap pattern
Source:http://sacomposite.com/filament_winding_carbon_fiber.
html 4/5/9
Pultrusion
• Continuous fibers
• Dipped into matrix
• 2 options:
– Pulled through die and cured
– Laid up into an open mold (and later cured)
http://www.tangram.co.uk/TI-Polymer-Pultrusion.html
Source:
http://www.ale.nl/ale/data/i
mages/Pultrusion.jpeg 4/5/9
Open Mold Processes
• Hand lay up
– Oldest, labor intensive
– Mold required
– Fibers placed in mold:
• Dry fibers placed and then matrix added
– Pour or brush or spray >> rolled to achieve mixture
– Vacuum used to ‘pull’ matrix into fiber
• Prepeg placed in mold
Burton, Sharpe, Jenkins, Bossanyi: “Wind Energy Handbook”
Burton, Sharpe, Jenkins, Bossanyi: “Wind Energy Handbook”
Source: www.tpicomposites.com 3/2008
Source: www.tpicomposites.com 3/2008
Source: www.tpicomposites.com 3/2008
Reusable Silicon Bag Technology for
®
SCRIMP
o Silicone bags are rapidly fitted to the infusion tool
o Feed lines, vacuum lines and embossed distribution
channels are integrated into the bag improving the
repeatability of the process (TPI Patented Technology)
April 9, 2015
Courtesy: Nolet, TPI
28
Fibers
• Woven Fabrics
– Higher cost, less applicable as structural
components for blades
• Non-woven Multiaxials
– Most widely used in VARTM processes
– Low-cost, non-crimp form results in
superior performance
– “Uni-directional”, Biaxial, Double Bias,
Triaxial and Quadraxial material forms
available.
Courtesy of Saertex USA
April 9, 2015
Courtesy: Nolet, TPI
29
Resin Matrices
• Epoxies remain a primary resin
of use in European based
blade designs
• Vinyl-esters are attracting
much interest by blade
designers
• Polyester resins are still
prominent in the industry.
• Thermoplastics and other
matrices
April 9, 2015
Courtesy: Nolet, TPI
30
http://www.compositesworld.com/articles/carbon-fiber-in-the-wind.aspx
Blade Components
Infused Together
• Skin
– Composite
– Core
• Spar cap
– Composite
• Shear web
– Composite
– Core
• Root Section
– composite
Other Materials
• Bond paste
• Hardware
• Balance box
• Paint
• Lightening protection
system
• Platform
Quality Issues
• Waves
– Aspect ratio (L/a)
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Bond failure
Dry infusion
Lack of continuous fibers
Geometrical errors
Fabric assembly errors
Figures from: “Yerramalli, Miebach, Chandraseker, Quek: “Fiber Waviness
Induced Strength Knockdowns in Composite Materials Used in Wind Turbine
Blades”. 2010
Process Steps
• Cut fabric
• Preforms
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–
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Layup
Infuse
Inspect
Trim
• Shell
– Layup
– Install preforms
– Infuse
• Assembly
– Shear web
– 2 shells
• Finishing
– Finish edges
– Wet layup
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Final cure
Drill and cut end square
Finishing and painting
Hardware
Balance box
Final inspect
Burton, Sharpe, Jenkins, Bossanyi: “Wind Energy Handbook”
Burton, Sharpe, Jenkins, Bossanyi: “Wind Energy Handbook”
Mark Higgins 9/15/2011 Presentation at ISU
Mark Higgins 9/15/2011 Presentation at ISU
Mark Higgins 9/15/2011 Presentation at ISU
Mark Higgins 9/15/2011 Presentation at ISU
Mark Higgins 9/15/2011 Presentation at ISU
Mark Higgins 9/15/2011 Presentation at ISU
Assembly Variation
• Maintain +-mm across
50m assembly
• Joints are critical
43
Future Automation Systems?
Rapid Material Placement Systems
(RMPS)
Automated blade molding
Automated root end machining for
wind blades
Machine adapts automatically to blade
position
Machining processes: Sawing, milling,
boring and trimming
http://mag-ias.com/index.php?id=308&L=2
Options for Large(r) Blades
• Manufacturing
– Make at point of use
– Make in region of use
– Import
• Design
– Flatback design
– Design in 2 pieces
– Materials to reduce
weight
Remote Blade Manufacturing Demonstration –
Sandia 2003