1IV/20100429
Composite Materials:trends and challenges
Ignaas VerpoestComposite Materials Group,
Department Metallurgy and Materials Engineering, K.U.Leuvenand
Sirris-Leuven Composites Application Lab
2IV/20100429
Composites: what?
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Composites: why?
• Ashby’s diagrams:
0.01 0.1 1 10Density, ρ (Mg/m3)
1000
100
10
1
10-1
10-2
10-3
10-4
Youn
g’s
mod
ulus
E (G
Pa)
Modulus - Density
foams
Polymers
Elastomers
Naturalmaterials
Composites
Metals
Ceramics
Plate bending
Tension
4IV/20100429
Composites: why?
Conclusion: High specific strength and stiffnesslighter structuresLess energy consumption during manufacturing ànd use
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Composites: how important?
• Annual production of fibres for composites (estimations):– Glass fibres: 250.000 ton– Carbon fibres: 30.000 ton– Natural fibres: 40.000 ton– …compared to
• Steel: 800.000.000 ton• Polymers: 120.000.000 ton
• Annual growth rates of (some) composite applications– thermoplastic matrix composites : 8 % (now 37% market share)– closed moulding (RTM, RTM-light, infusion): 13 % yearly (now 10 % market
share in EU)– Aerospace structures: +11% p.a.– Wind energy composites: +16 % p.a.
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Composites: how important?
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Trends and challenges
TRENDS1. Proliferation of carbon fibres
2. Intelligent fibre architectures
3. Sustainable composites
4. Automated manufacturing
5. Recycling
6. …and nano?
CHALLENGES
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Trend 1: the proliferation of carbon fibres
• Carbon fibres:– started in aerospace in ’80s– Developed into sports and industrial applications in ’90’s– Are now penetrating into ‘high volume applications’ because of
• Long term perspective for stable costs (possibly decreasing)• Strong emphasis on sustainable, hence low energy consumption
products
• Example: BMW decided – Their “city car” (electrical or
hybrid) will be a carbon fibre composite car
– They will build their own carbon fibre manufacturing plant (together with SGL)
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Trend 2: intelligent fibre architectures
• From individual textile layers… to structurally stitched components!
2D Weaves
3D Weaves Knitted fabrics
Braids
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Trend 3: Sustainable composites
• Natural fibres: strong increase in
• Developments for composites
• Industrial interest
• Biopolymers– Preferred route should
• No compete with food
• Add little ‘chemistry’
Gluten
ResinBio-based
Polymer or CompositeMaterial
Controlled-releaseNitrogenFertilizer
Wheat
agriculture
Starch
industrialprocessing
recycling
chemical or(bio)catalyticmodification
polymerprocessing
Compost
composting
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Trend 4: automated manufacturing
• Driven by trend to ‘high volume applications’– Already happening in
• Sports equipment• Aerospace:
– at hundreds of composite aeroplanes/year– Thousands for similar components have to be produced– Hence automation is needed!
– Soon expected in automotive!
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Trend 5: recycling
• Necessity for ‘high volume applications’ • Two developments:
– Glass fibre composites:• Trend towards thermoplastic composites• Potential for alternative fibres which improve recyclability:
– Basalt fibres– Natural fibres– Steel fibres
– Carbon fibre composites:• Processes for recovery of carbon fibres are ready to operate!
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Trend 6: and nano?
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Meso
Micro
Nano
Fabric architecture
Fibers inside yarns
Structure of matrix
Multiphase epoxy Carbon nanotubes
Cracks in transverse ply Debonding at matrix/fiber interface
stiffness
failure resistance
Trend 6: … and nano?
4
15IV/20100429
Trends and challenges
TRENDS1. Proliferation of carbon fibres
2. Intelligent fibre architectures
3. Sustainable composites
4. Automated manufacturing
5. Recycling
6. …and nano?
CHALLENGES