Nonwovens made of recycled carbon fibres as basic material for composites

Transcription

1 Nonwovens made of recycled carbon fibres as basic material for composites Dr. Heike Illing-Günther Dipl.-Ing. (BA) Marcel Hofmann Dipl.-Ing. Bernd Gulich Saxon Textile Research Institute, Chemnitz (Germany) 1

2 Agenda Carbon fibres - applications and necessity of recycling Results of different research challenges Available systems engineering at STFI Future prospects 2

3 Why Recycling of carbon materials? Increasing amount of cutting scrap (production waste) High percentage of non-rectifiable rejects Increasing amount of end-of-life-waste in near future Ban on landfill for CFRP materials Incineration is problematic and expensive Legislation (e.g. ELV) 3

4 Carbon fibre nonwovens Investigation of the process ability of long carbon fibres Beginning of the first project: The used fibre material was produced by cutting the raw material in form of rovings with a chopper Second stage: Cutting and tearing of production waste/cutting scrap of resin free CF fabrics Third group: Carbon fibres, resulting from recycled composite parts after pyrolysis or others i.e. solvolysis Objectives: Production of fabrics made from carbon fibres on dry way in a mechanically operated web formation process 4

5 Manufacture of nonwovens Processing of long, but not endless carbon fibres by means of the carding principle In-line entanglement using stitch-bonding technique MALIWATT or needle-punching Before: Preparation of different CF waste /cutting scraps or CF coming from i.e. pyrolysis using modified cutting and tearing processes Afterwards: Testing of the fabric features by use of different process lines 5

6 Available systems engineering at STFI Cutting Carding Sliver processing Tearing Lapping Needlepunching Stitchbonding Thermofixation Take-up 6

7 Carbon fibre nonwovens lab 7

8 Different fabrics: Stitch-bonded nonwoven MALIWATT - face wale Fibre web: 100 % Carbon fibre Stitching yarn: PES-S texturized; 7.6 tex MALIWATT - reverse wale 8

9 Different fabrics: Needle-punched nonwoven Fibre web/nonwoven: 100 % carbon fibre 9

10 Textile physics Realized mass per unit area: g/m² Realized thickness: mm Strength / elongation Shaping / drapability via static puncture test (according to DIN EN ISO 12236) 10

11 Verformung [mm] Shaping/drapability via static puncture test Verformung 11

12 Force-deformation diagramme Carbon Fibre Nonwoven MALIWATT; cross oriented, Tricot Mass: 410 g/m² Stitching yarn: PES texturized; 7.6 tex Carbon Fibre (Roving)-Woven Plain weave Mass: 300 g/m² 12

13 Fibre volume content 13

14 Composite facilities at STFI FRP lab (in upgrading) Hand lamination Press & injection devices Testing equipment Tensile strength Bending strength Interlaminar shear strength (ILSS) Compression test CF preform Moulding press 14

15 Results Web formation by means of carding using 100% carbon fibres is technically possible Nonwovens of 100 % CF from i.e. pyrolysis are possible via needle-punching Products have a profile of characteristics which qualifies them for the use in CFRP structures with medium strength requirements Ideal applications are in the areas of Integrated functional lightweight construction Sports / rehabilitation technology Leisure activities (e.g. camping) General construction Architecture 15

16 Possible ideas of use Vehicle manufacturing, engineering, sports and leisure equipment, wind power plants, medical engineering, architecture High wall thicknesses with low weight are possible Quelle: Opel Extreme high deformation potential during preform shaping in the mould 16

17 Outlook On-going determination of different processing lines also as hybrid fibre blends for thermobonding and other alternative entanglement processes Characterization of UD oriented nonwovens/ composites (via sliver processing and their parameters compared to load bearing capacity of primary fibres/rovings Separation of stitching yarns after cutting/tearing of resin free NCF 17

18 Acknowledgement The publication results from projects which were supported by the Federal Ministry of Economics and Technology under Reg.-No. VP VT0 and VF We thank the Federal Ministry of Economics and Technology (BMWi) for the financial promotion. 18

19 Sächsisches Textilforschungsinstitut e.v. (STFI) an der Technischen Universität Chemnitz Saxon Textile Research Institute at Chemnitz University of Technology International Competence in Technical Textiles Nonwovens Protective Textiles 19

20 Thank you for your attention! Sächsisches Textilforschungsinstitut e.v. Annaberger Straße 240 Managing Director: Chemnitz Dipl.-Ing.-Ök. Andreas Berthel Phone: Fax: Internet: 20