High Volume Manufacturing of Carbon Fiber Reinforced ...

1 - Materialien des Karosseriebaus, Bad Nauheim David Roquette, Dr. Florian Meyer - AUDI AG Dr. Lars Herbeck - Voith Composites GmbH & Co. KG high Volume Manufacturing of Carbon Fiber Reinforced Plastics for Body in White Global and Automotive Trends Projects and Aims for the Introduction of CFRP Technology Development Carbon Rear Wall Realization at Voith Composites Conclusion Content Global Trends - Challenge for the Automotive Industry Regulations Emissions and Electrification Individualisation Sustainability Digitalisation Smart Connect Automotive Trends - Challenge: Weight Increasing Factors Innovations and comfort- for self driving concepts Safety requirements CO2 emissions e. g.

2 Electrification of power train (PHEV, BEV, ..) Legislation (NOX, Ad ) Country specific regulations Density of steel, aluminum, Carbon Fiber Reinforced plastics (CFRP) approx. 5:2:1 Costs approx. 2:10:50 Weight reduction potential in body applications approx. 100:70:60 Efficient weight reduction ( /kg) as the aim for the Audi Multimaterial Space Frame. The right material at the right place in the right amount Typical Materials for Body in White 7,8 2,7 1,5 Density [kg/dm ] 2 4 6 8 10 0 Steel CFRP Aluminium Steel Normalized car-body weight[%] 100 0 Steel Aluminium CFRP Aluminium CFRP Steel Cost [ /kg] 0 Bugatti Veyron First-time evidence Class-A LB Gallardo Spyder Class-A evidence with large, horizontal component R8 Coup predecessor Sideblade with visible-CFRP R8 Spyder predecessorNumber of units 20/day Class-A CFRP RS3 Number of units 40/day Class-A CFRP R8 e-tron CFRP in structure CFRP in crash area New Audi R8 / Lamborghini Hurac n Number of units 45/day CFRP in structure Standardization CFRP in structure Cost reduction with high number of units New A8 Number of units 150-300/day Industrialization technological level Class-A in RTM with large component Visible CFRP in RTM Complex geometry Number of units Maximization of lightweight potential CFRP in structure Cost reduction Class-A in RTM timeline Projects and Aims for the Introduction of CFRP 1st step.

3 Development of basic technology Class-A and visible-CFRP 2nd step: built up competence for high Volume 3rd step: cost reduction and integral design Breakthrough technologies are developed at the Audi lightweight Center and transferred with potential suppliers to serial production. material and Process Development for Large Structures with Integral design 2012 2014 2015 R8 (MSS) Coup Differential design Predevelopment Project R8 (MSS) Coup Integral design 2013 R8 (MSS) Spyder Integral rearwall and B-pillar R8 Prototypes R8 (MSS) Spyder Integral design 2016 2017 Approach and Realization: Integral design and high Volume 3rd step: cost reduction and integral design 2nd step: built up competence for high Volume A8 (D5) Integral design high Volume Carbon Rear Wall A8 Prototypes (D5) CFRP in the Audi R8 and the New Audi A8 - Multimaterial Audi Space Frame Audi R8 Coup and Spyder Modular Sportscar System (MSS) New Audi A8 Small Series to high Volume Single part reduction and integration of function due to an integral design Preassembled module within assembly line Highly anisotropic layup with localized load paths 1 2 Necessary Steps in Technology Development from R8 to A8 Appropiate composite-based design Materials & Technology Cost efficient Composite Solution Package ( Carbon Fiber , Resin & Adhesive)

4 New Ultra-RTM Technology (low mould pressure/ robust process / short cycle-time ) Innovative direct Fiber placement technology (reduced scrap & optimized layup) Highly automated and linked Manufacturing process Carbon Rear Wall Structure - Functional Integration Density -45% 1 D4 Current A8 D5 New A8 Weight -50% D4 D5 D4 D5 Single part reduction and integration of functions are realized due to an integral design . Preassembly of several components parallel to assembly line. Carbon Rear Wall - Maximizing Anisotropy 1 Minimum use of Carbon Fiber due to highly anisotropic layup with localized load paths. Highlights 6-19 optimized layers high variety in part thickness: / / / / mm 30% of static torsional stiffness are related to the Carbon rear wall Materials - Efficient Composite Solution Package 2 Carbon Fiber Zoltek Panex PX35 Zoltek PX35 50k large tow Fiber Optimized balance of performance and costs for high Volume applications Long term price commitment up to 7 years Textile Type PAN based precursor Stability of Supply Resin & Internal Mould Release VORAFORCETM 5300 - Epoxy RTM Curing time 90-120s @120 C Open - Cure time ratio 1.

5 2 Processing viscosity <20mPas Latent reaction behavior Effective mold release Excellent Fiber adhesion No post cure required high machine compatibility Adhesive BETAFORCETM 9050M Used for metal inserts and assembly Compatible with VORAFORCETM & IMR Pretreatment-free adhesion heat accelerated cure and ambient temperature latency Multi material mix Da management ( high elongation and stiffness) price-performance ratio for tensile properties Composite stiffness GPa/ Composite strength MPa/ performance automotive fibre low-cost automotive fibre Source: Dow Automotive Systems Source: Dow Automotive Systems Large Parts Low Pressure Fast Injection Technology and Process - ultra-RTM D5 Prototype 2 Standard-HP-RTM: pick only two Main challenge: Infiltration of complex parts with ultra-fast-cure resins and very low cavity pressure could be solved by innovative process controlled injection and press step.

6 Ultra-RTM Fibre clamping resin stops at clamping, no resin sealing needed Resin Shot weight: kg Sprue: point injection, no resin channel Mass flow: 130 g/s Time press open to open: <180 s RTM-tool bottom side RTM-tool with dry preform Cured part before demoulding Dry fibers outside clamping ultra-RTM technology can produce the same quality with smaller, efficient hydraulic presses and a very robust process also for high Fiber Volume content (50-55%). Technology and Process - ultra-RTM D5 Prototype 2 0500010000150002000025000005101520253035force [KN] time [s] 0,00,20,40,60,81,0005101520253035gap height [mm] time [s] 020406080100120140005101520253035pressure [bar] time [s] Injection Compression Curing In Mould Pressure During Injection Press Force During Process Gap Height During Process 130 g/s 65 g/s >130 g/s End of injection End of compression HP-RTM classic Advanced RTM ultra-RTM 2500t Press Force 350t Press Force Technology Transfer to Serial Production Breakthrough technologies are developed at the Audi lightweight Center and transferred with Voith Composite to serial production.

7 Voith Composites From Fiber Straight to Component .. manual processing Yesterday .. Today .. automated processing Elimination of expensive semi-finished products, reduction of cycle time due to elimination of process steps, completely digitalized production based on Carbon Production 16 Voith Composites | Bad Nauheim Materialien des Karosseriebaus | 16. Mai 2017 | confidential 17 Industrialized Process Chain CFRP Rear Wall Audi A8 Materials Assembly Semi finished Preforming Consolidation Milling Mostly industrialized Mostly industrialized Manufacture Standard Materials Preforming Consolidation Industrialized Production Assembly Milling Lean Fiber Placement (VRA) 3D Forming 3D Cutting Ultra RTM Process CNC Milling Surface Cleaning Riveting & Bonding Fiber & Binder Resin Metallic Attachment Parts Details Voith Composites | Bad Nauheim Materialien des Karosseriebaus | 16.

8 Mai 2017 | confidential 18 Process Chain Step: Voith Roving Applicator (VRA) Fiber Placement 3D Forming 3D Cutting Ultra RTM CNC Milling Cleaning Assembly Industrialized production line Near net shape Fiber placement Automated quality control Fully digitalized Flexible 2D Fiber layup Variable Fiber angle Voith Composites | Bad Nauheim Materialien des Karosseriebaus | 16. Mai 2017 | confidential 19 Fiber Placement 3D Forming 3D Cutting Ultra RTM CNC Milling Cleaning Assembly Process Chain Step: 3D Forming Segmented stamp forming Complete automated handling Forming process 2D 3D Activation of binder Tailored Preforms Stabil in RTM process Voith Composites | Bad Nauheim Materialien des Karosseriebaus | 16.

9 Mai 2017 | confidential 20 Process Chain Step: Injection & Consolidation Ultra RTM Fiber Placement 3D Forming 3D Cutting Ultra RTM CNC Milling Cleaning Assembly Fully industrialized process high production rate Curing time < 120 s. Low injection pressure Optimal surface quality No Fiber washing Voith Composites | Bad Nauheim Materialien des Karosseriebaus | 16. Mai 2017 | confidential 21 Process Chain Step: Riveting and Bonding of Metallic Parts Fiber Placement 3D Forming 3D Cutting Ultra RTM CNC Milling Cleaning Assembly Surface cleaning with water No mechanical treatment for bonding necessary Fully automated bonding Fast curing 2k PU System Automated riveting Riveting force documentation The new A8 CFRP Rear Wall has a weight reduction of 50% compared to the current A8.

10 Breakthrough technologies have been developed at the Audi lightweight Center and together with Voith Composites transferred to serial production. Due to the new developed technologies it is possible for the first time to use the full potential of CFRP within high Volume . Lean production: Voith Roving Applicator for elimination of semi finished products Industrialization: mechanization and automation of processes Conclusion TechDay Body Structure Thank you