eco-composites - german aerospace center 04 18 grain2 kgt3 eco-materials … · •...
TRANSCRIPT
EU-China Week on Aviation Research, Brussels 18-20 April 2016
ECO-COMPOSITES
Jens Bachmann (DLR)
EU-China Week on Aviation Research Brussels, 18-20 April 2016
EU-China Week on Aviation Research, Brussels 18-20 April 2016
Content
• Background
• Possible applications of eco-composites in aviation
• Properties of eco-materials
• Conclusions
2
EU-China Week on Aviation Research, Brussels 18-20 April 2016
Background • Composite materials with reduced ecological impact • „Definition“ of Eco-Composites for this presentation
– Natural Fibre Reinforced Plastics (with petrol based matrix) – Bio-resins combined with man-made fibres – Bio-Composites (resin and fibre renewable, not necessarily 100%...) – Recycled Materials
• What is the motivation to use eco-materials in aviation?
– Improved ecological footprint -> „green“ image – Good specific properties – Multifunctional aspects
3
EU-China Week on Aviation Research, Brussels 18-20 April 2016
Bio-fibres & bio-resins
4
Linum usitatissimum
EU-China Week on Aviation Research, Brussels 18-20 April 2016
Possible applications of eco-materials in aviation: Interior
• Challenges – Fire properties (FST + HR) – Weight compared to currently used sandwich panels – Sensitivity for liquids and humidity
5
EU-China Week on Aviation Research, Brussels 18-20 April 2016
Properties of eco-materials • Comparison of “bio”-resins with standard phenolic resins • Natural fibre (NF) and glass fibre (GF) reinforcement
[Bachmann, J., Fischer, H. – Bioharze und flammgeschützte Naturfasern: Nachhaltige Materialien für das Flugzeuginterieur? – AVK-Flammschutz bei Composites-Anwendungen, Frankfurt, 10.12.2013]
0
50
100
150
200
250
300
350
400
PF(Ref) EP1 EP2 FUR ACR
[kW
/m²]
Heat Release Rate - AITM 2.0006
0
50
100
150
200
250
300
PF(Ref) EP1 EP2 FUR ACR
[mm
]
Burn Length - AITM 2.0002B
6
EU-China Week on Aviation Research, Brussels 18-20 April 2016
Properties of eco-materials • Fire properties of natural fibre
reinforced plastics (Interior, Sandwich) • Fibre: Flax (plain weave, non-woven) • Resin: Phenolic (standard for cabin use) • Core: Nomex® Honeycomb (standard)
[Bachmann, J., Michelis, B. – Verbesserung der Brandeigentschaften von NFK im Hinblick auf den Luftfahrt-Kabineneinsatz – Köln 2011]
7
EU-China Week on Aviation Research, Brussels 18-20 April 2016
Recycled carbon fibres • Pyrolysis process industrially
available • Less energy consumption • Elimination of fibre sizing • Resin residue and „craters“ on rCF • Strength of rCF comparable to vCF • Restricted fibre length
vCF = Virgin Carbon Fibre rCF = Recycled Carbon Fibre
[DLR]
8
EU-China Week on Aviation Research, Brussels 18-20 April 2016
Possible applications of eco-materials in aviation: Secondary Structures
• Challenges – Mechanical properties compared to current structural materials – Quality of reinforcements – Robustnes – Sensitivity for environmental influences – Cellulose: Additional calorific potential during post crash fire
9
EU-China Week on Aviation Research, Brussels 18-20 April 2016
Properties of eco-materials
• Mixing rCF and NF • „Hand-made“ non-woven • Epoxy resin • Fibre volume fraction ~ 30% Plasma activation (trial) reveals potential of rCF
0
50
100
150
200
250
300
100% NF 75% NF+ 25% rCF
75% NF+ 25% rCF(Plasma)
σ_3
PB [M
Pa]
Flexural strength (ISO 14125)
+15%
+44%
10
EU-China Week on Aviation Research, Brussels 18-20 April 2016
DLR Demonstrators
11
EU-China Week on Aviation Research, Brussels 18-20 April 2016
Conclusions • Bio-fibres are able to substitute glass fibres with their good specific
properties • Safety requirements (FST) could be fulfilled, but the mechanical
properties, weight and impact on LCA must be considered • Resins based on renewable materials are available, some offer comparable
fire properties compared to petrol-based phenolics • Recycled fibres are available and their quantity will rise in the future while
the prise is expected to decrease, offering a “greener” alternative to virgin fibres with some restrictions (e.g. length)
• Hybrid composites based on renewable and recycled fibres offer the potential to use more ecological improved materials in aviation
Eco-materials offer the potential to decrease ecological footprint of aviation when the total weight of the parts does not increase, but every case should be validated with Life Cycle Assessment
12
EU-China Week on Aviation Research, Brussels 18-20 April 2016
谢谢大家的关注。 Thank you for your attention.
13