High-Tech Plastics for Lightweight Solutions

High-Tech Plastics for Lightweight Solutions Julian Haspel, High Performance Materials, Global Application Development Mobility Days Prague, November 22nd 2012

Agenda Plastic / metal hybrid technology Composite technology CAE integrative simulation for thermoplastic composites Application fields 2

Plastic / metal hybrid technology (PMH) the principle Denting or buckling of lightweight structures due to the thin wall F 1 Strengthening the structure with small forces carried by plastic ribs F 1 Sheet metal F 2 F 2 Support F 1 >> F 2 High-tech plastics keep metal in shape 3

Plastic / metal hybrid technology (PMH) the principle Form fit between plastics and metal 4

The history 1. Generation System carrier 1997 Module carrier 2. Generation In-mold assembly 3. Generation Optical surfaces Structural part Proven technology 5

Today standard PMH for frontends Hybrid technology with steel insert Durethan BKV 30 H2.0 (PA 6 GF 30) Audi A6 1998 Mercedes Benz A 2004 Audi A4 2000 Ford Focus 1998 Ford Fiesta 2001 Renault Megane 2002 Chrysler 300C 2004 VW Polo 2001 Nissan Quest 2003 BMW X3 2003 Ford S-Max 2006 Audi TT 2006 Hyundai Avant 2006 Hyundai Veracruz 2006 Hyundai i30 2007 Hyundai Starex 2007 Audi A8 2010 Advantages against steel 10-50% weight reduction 10-40% cost reduction High function integration with reduced process steps Higher accuracy and quality Ford Galaxy 2006 Ford Mondeo 2007 Audi A5 2007 Audi A4-2007 Audi Q7 V12 2008 Audi A3 2008 Audi A7 2010 Audi A1 2010 BMW 1er 2004 Hyundai Santa Fe 2006 Audi Q5 2008 BMW 3er 2005 Higher load capacity KIA Carens 2006 More than 70 applications and 50 million manufactured parts 6

PMH wide application scope and evolution Pedal bracket Break pedal Mercedes C-Class mass production since 03/2007 Roof frame Structural inserts Audi A6 (2004) Hybrid technology with aluminum Audi TT (2006) x xxfiat Ducato mass production since 06/2006 Citroën C4 Picasso (2006) Great potential for future development 7 Source: Audi

Current developments cooperation across industries Current technology positive locking bond New technology adhesive bond Metal Metal Polymer Polymer Primer / glue Molded button Expectations: weight neutral performance increase resp. ~ 30% weight reduction compared to standard PMH 8

LANXESS product development for lightweight solutions Product characteristics development Highly reinforced PA or PBT compounds 250 Examples 200 - Durethan DP BKV 60EF (60% GF) % 150 100 50 0 BKV 30 GF30 BKV 30EF GF30 BKV 30XF GF30 DP BKV 60EF GF60 Flowability Tensile strength Stiffness - Pocan T3150 XF (55% GF) High modulus (HM) High strength Low viscosity resins allow incorporation of high fiber amounts Ideal for lightweight solutions 9

Example Audi A8 spare wheel well: HM grades with gas-injection-technology (GIT) Durethan DP BKV 60 H2.0 EF (PA 6 + GF60) Heat stabilized and easy flow PMH with aluminum and GIT Shot weight: 12 kg Part weight: 9 kg Advantages Cost and weight reduction compared to SMC* or metal design Enabling high function integration Glued into the BIW** contributing to the stiffness of the car Not feasible in pure metal design Superior to pure metal designs GIT Channel 10 *Sheet Mold Compound **Body in White

Agenda Plastic / metal hybrid technology Composite technology CAE integrative simulation for thermoplastic composites Application fields 11

Further development hybrid technology with composite sheet Composite sheet Thermoplastic (PA) matrix materials reinforced with woven fabrics Glass, carbon or aramid fibers (also hybrid) Continuous fibers (fiber length = part length) Advantages of hybrid composite parts Low weight (density e.g., 1.8 kg/dm³) High stiffness, strength and energy absorption No corrosion, simple recycling No investment for additional tools Frontend Audi A8 Full-plastic composite parts as alternative to plastic-metal structures 12

Integration of composite sheet into the hybrid composite part through in-mold forming. IR heater Heating up above melting point Shaping during the closing of injection molding tool Subsequent injection molding of rib pattern Demolding 13

Example in-mold formed hybrid composites Door impact beam (demonstrator) Steering column bracket Tepex + Durethan BMBF-Project SpriForm in cooperation with Tepex + Durethan Project in cooperation with 14

Simulation is mandatory for the development of new applications Hybrid composite parts New material (composite sheets) New process (one shot molding) Simulation required for - Mechanical component behavior - Processing (forming and molding) LANXESS contribution New technology in virtual reality Shortened development times Reduced development costs Parts designed to the limits No application without simulation 15

Agenda Plastic / metal hybrid technology Composite technology CAE integrative simulation for thermoplastic composites Application fields 16

Challenges encountered in composite sheet simulation Stress [MPa] Tensile tests in different directions* Strain [%] 0 7.5 15 22.5 30 37.5 45 Main mechanical characteristics Anisotropy Non-linearity Strain rate dependency Different tension / bending stiffness Failure / breakage Rotation of fiber directions / non-orthogonal fiber directions Temperature dependency Moisture dependency 17 * Tepex dynalite 102-RG600(x)/45%

Validation of benchmark material model developed by LANXESS Tensile tests 0 at different strain rates* Tensile tests 45 at different strain rates* Stress [MPa] Stress [MPa] Strain [%] M qs M 1 1/s M 10 1/s M 100 1/s S qs S 1 1/s S 10 1/s S 100 1/s Strain [%] M qs M 1 1/s M 10 1/s M 100 1/s S qs S 1 1/s S 10 1/s S 100 1/s 18 * Tepex dynalite 102-RG600(x)/45%

Processing of composite sheets via thermoforming Two composite sheet processing methods 1 Forming mechanisms metal vs. composite sheet Metal sheets Composite sheet 1 Folding Fiber orientation known Only simple geometries 2 Forming Fiber orientation not known Complex geometries possible 2 vs. Metal sheets Plastic deformation A deformed > A undeformed Wall thickness distribution Composite sheets Shear ( Trellis effect) A deformed A undeformed Fiber orientation distribution 19

Forming / draping simulation of composite sheet example: mouse bath tube Forming simulation Forming behavior Orientation of composite sheet 0 > 0.96 < 0.96 22.5 45 + 55 Change of fabric angle - 55 20

Integrative simulation of hybrid composite parts Material Development Forming properties Mechanical properties Computer Aided Engineering Forming simulation Fiber orientation Mapping Material model: Tepex 21

Fiber orientation of injection-molded parts Orientation due to flow Result: anisotropic layer V Core: to flow (fountain flow) Boundary: random V Flow Orientation Extensional perpendicular Shear parallel Shear layer: ll to flow 22

Mechanical behavior depending on fiber orientation 2500 Durethan BKV 30 H2.0 cross 2000 long 1500 Force [N] 1000 500 0 0 0.5 1.0 1.5 2.0 2.5 3.0 Displacement [mm] - 35ºC / dry / long 23ºC / dry / long 23ºC / ISO 1110 / long 85ºC / dry / long - 35ºC / dry / cross 23ºC / dry / cross 23ºC / ISO 1110 / cross 85ºC / dry / cross Alternative universal valid isotrop values do not exist 23

Workflow integrative simulation for injection-molded parts FE-model (rheology) Moldflow FE-model (mechanic) Micromecanical model Stiffness of fiber and matrix Geometry of fiber (L/D) Volumetric content of fiber ϕ Fiberorientation (rheology) Mapping Fiberorientation (mechanic) Unidirectional composite Orientation averaging Real composite Anisotropic material model with failure crit. Strength of Fiber Matrix Composite Non linear material FEA: stiffness and strength of IM part 24

Elastic-plastic matrix properties tension tests 0º / 45º / 90º to flow direction 1200 Durethan BKV 30 H2.0 1100 Room temperature (23ºC) Conditioned according ISO 1110 1000 900 800 700 Force [N] 600 500 400 300 200 100 Simulation 0º Simulation 90º Simulation 45º Tests 0º Tests 90º Tests 45º 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 Displacement [mm] 25

Integrative simulation of hybrid composite parts Material Development Forming properties Mechanical properties Mechanical properties Molding properties Computer Aided Engineering Forming simulation Fiber orientation Material model: Tepex Material model: Durethan Pocan Molding simulation Fiber orientation Mapping Mapping 26

Bonding strength of injection-molded part to composite sheet Injection-molded plates on composite sheet* Tensile test bonding strength Bonding strength depends on Preheating of composite sheet Injection-molded parameters Flow length Material 27 * LANXESS tool

Integrative simulation of hybrid composite parts Material Development Forming properties Mechanical properties Interface properties Mechanical properties Molding properties Computer Aided Engineering Forming simulation Fiber orientation Material model: Tepex Material model: Durethan Pocan Molding simulation Fiber orientation Mapping Mapping 28

Validation example 1 pole impact test of a door impact beam demonstrator Pole impact test b a Force [N] b a Displacement [mm] Measurement Simulation c c 29

Validation example 2 three point bending test of the upper beam of a frontend (1/2) Part Testing setup Three point bending test Tepex + Durethan Projekt in Cooperation with Faurecia Force [N] Two different LANXESS rib materials Durethan BKV 30 H2.0 Durethan DP BKV 60 H2.0 EF Simulation Durethan BKV 30 Simulation Durethan BKV 60 EF Displacement [mm] Measurement Durethan BKV 30 Measurement Durethan BKV 60 EF 30

Validation example 2 three point bending test of the upper beam of a frontend (2/2) Failure behavior Three point bending test Force [N] 1 Displacement [mm] 0 Simulation Durethan BKV 30 Simulation Durethan BKV 60 EF Measurement Durethan BKV 30 Measurement Durethan BKV 60 EF 31

Prototype in cooperation with ZF Friedrichshafen AG Test results of the prototype Static loads have been tested at room temperature passed Weight saving correlates with calculations Benefits Function integration Reduction of process steps Equally distributed loads Corrosion protection superfluous Weight saving Easy recycling Partnering for progress 32

Validation example 3 brake pedal (prototype) Part Testing setup Force [N] Measurement Simulation Tepex + Durethan Project in Cooperation with ZF Friedrichshafen a b c d Displacement [mm] Failure in the composite sheet ca. 0.97 ca. 1.02 (first crack) >> 1 Area of failure a b c d 33

Agenda Plastic / metal hybrid technology Composite technology CAE integrative simulation for thermoplastic composites Application fields 34

High-tech plastics for lightweight applications Gas tank carrier Roof frames Airbag housings Module carrier Selection Cross car beams Battery housing carrier Frontends Battery cell holder Steering rod Pedals / pedal brackets Brackets 35

LANXESS for innovative lightweight solutions LANXESS offers extensive know-how in lightweight solutions Self-developed top-notch simulation tools Contributing to innovations with new technologies and high-performance materials Ready to jointly work on new applications 36