DIGIMAT FOR CONTINUOUS FIBER REINFORCED COMPOSITES

Transcription

1 DIGIMAT FOR CONTINUOUS FIBER REINFORCED COMPOSITES Roger Assaker, Pierre-Paul Jeunechamps, Jan Seyfarth, Laurent Adam May 2011

2 DIGIMAT FOR CONTINUOUS FIBER REINFORCED COMPOSITES The Challenge Continuous fiber reinforced composites in automotive industry Synergy between different industries Simulation technology for Continuous fiber reinforced composites e-xstream engineering DIGIMAT Software Application example: Wind Turbine Rotor Blade Simulation Approach Model Materials Results Courtesy of Summary Thursday, May 26, 2011 Copyright e-xstream engineering,

3 The Challenge Continuous fiber reinforced composites in automotive industry Glass fiber reinforcement (GFRP) Carbon fiber reinforcement (CFRP) PROS Strong, stiff and light CONS High material costs Long manufacturing cycle times Some applications already exist (sports cars, formula 1) Not yet used in mass production vehicles Seen as the technology for the future... Thursday, May 26, 2011 Copyright e-xstream engineering,

4 The Challenge Sources: Continuous fiber reinforced composites in automotive High-end sports cars Mercedes-Mclaren SLR Lamborghini Aventador Thursday, May 26, 2011 Copyright e-xstream engineering,

5 The Challenge Sources: Continuous fiber reinforced composites in automotive Future technology - CFRP passenger compartment BMW JEC Composites 2011 Hybrid concept car BMW i3 / BMW i8 Thursday, May 26, 2011 Copyright e-xstream engineering,

6 The Challenge Source: Can Carbon fibers compete? Continuous fiber reinforced composites in automotive First approaches towards mass production Production facility in Landshut, Germany Serves as both a laboratory and pilot plant Houses what BMW calls "the world's first highly automated production process for CFP body components." roofs produced for the M3 CSL coupe in 2003 Increasing demand can bring price down to some acceptable level BMW and VW fight over SGL Carbon Access to carbon fiber ressources is critical Thursday, May 26, 2011 Copyright e-xstream engineering,

7 The Challenge Investigation of design concepts Synergy between different industries Run on Carbon fiber material is ongoing Strongly growing market in automotive Strongly growing market in renewable energy Thursday, May 26, 2011 Copyright e-xstream engineering,

8 The Challenge Investigation of design concepts Synergy between different industries Automotive Mass production needed Cycle times & costs critical Strong focus on carbon fibers Aerospace Automated production Cycle times not critical Glass & Carbon fibers Renewable energy Automated & manual production Cycle times not critical Mainly glass fibers Thursday, May 26, 2011 Copyright e-xstream engineering,

9 DIGIMAT Technology Simulation is key to the investigation of future designs For all of these industries there is a lack of sufficient material models to describe composites This is especially true for the demands from the automotive industry Material modeling must cover Different matrix properties» Nonlinear effects» Temperature dependency» Strain rate dependency Different fiber properties» Isotropic as well as transversely isotropic» Anisotropy Failure» Complex failure» Fatigue failure Thursday, May 26, 2011 Copyright e-xstream engineering,

10 DIGIMAT Technology e-xstream engineering Founded in 2003 The Business: Simulation Software & Services 100% focused on material modeling The team Strong & highly motivated High level of education Belgium Luxembourg Germany U.S. The product Louvain-la-Neuve Bascharage Munich Thursday, May 26, 2011 Copyright e-xstream engineering,

11 DIGIMAT Technology DIGIMAT Thursday, May 26, 2011 Copyright e-xstream engineering,

12 DIGIMAT Technology Material modeling Setup the material model Thursday, May 26, 2011 Copyright e-xstream engineering,

13 DIGIMAT Technology Material modeling Reverse Engineer material parameters Thursday, May 26, 2011 Copyright e-xstream engineering,

14 DIGIMAT Technology Interface to Drapage simulation Thursday, May 26, 2011 Copyright e-xstream engineering,

15 DIGIMAT Technology Coupled solution FEA Drapage (4.2.1/4.3.1) Thursday, May 26, 2011 Copyright e-xstream engineering,

16 DIGIMAT Technology Multi-scale Simulation Thursday, May 26, 2011 Copyright e-xstream engineering,

17 Application Example Wind turbine rotor blade Virtual design of a wind turbine rotor blade Check the performance of (expensive) carbon fibers in the virtual environment Compare to the existing design based on glass fiber material Strategy Go from draping to FEA in a simple workflow Use one unique approach for the modeling of different composites Epoxy / Glass fiber Epoxy / Carbon fiber Define & use failure indicators on the microscopic level Max. Principle Stress in the fiber phase Max. Principle Strain in the matrix phase Thursday, May 26, 2011 Copyright e-xstream engineering,

18 Application Example Model Boundary conditions: The blade is fixed in displacement and rotation on the end where the blade is in real connected to the engine s rotor A pressure is uniformly applied on one side of the blade, in the opposite direction to acceleration s direction Loading: +Z linear acceleration applied on the blade Thursday, May 26, 2011 Copyright e-xstream engineering,

19 Application Example Model Shell sections 8 layers UD composite Composite properties exchanged by DIGIMAT material Thursday, May 26, 2011 Copyright e-xstream engineering,

20 Application Example Model Shell sections 18 layers 3 different materials Paint UD composite Foam Composite properties exchanged by DIGIMAT material Thursday, May 26, 2011 Copyright e-xstream engineering,

21 Application Example Materials UD composite / DIGIMAT model 1 Glass fiber reinforcement Epoxy matrix (Isotropic) Glass fibers (Isotropic) Density kg/m^3 E 3300 MPa PR 0.3 VF 0.4 Max Principal Strain (tens.) 5 % Max Principal Strain (comp.) 10 % Density kg/m^3 E MPa PR 0.22 VF 0.6 AR Max Principal Stress (tens.) 1500 MPa Max Principal Stress (comp.) 700 MPa Thursday, May 26, 2011 Copyright e-xstream engineering,

22 Application Example Materials UD composite / DIGIMAT model 2 Carbon fiber reinforcement Epoxy matrix (Isotropic) Carbon T300 fibers (Isotropic) Density kg/m^3 E 3300 MPa PR 0.3 VF 0.4 Max Principal Strain (tens.) 5 % Max Principal Strain (comp.) 10 % Density kg/m^3 E MPa PR 0.2 VF 0.6 AR Max Principal Stress (tens.) 2000 MPa Max Principal Stress (comp.) 1500 MPa Thursday, May 26, 2011 Copyright e-xstream engineering,

23 Application Example Materials UD composite / DIGIMAT model 3 Carbon fiber reinforcement Epoxy matrix (Isotropic) Carbon T300 fibers (Transversely isotropic) Density kg/m^3 E 3300 MPa PR 0.3 VF 0.4 Max Principal Strain (tens.) 5 % Max Principal Strain (comp.) 10 % Density kg/m^3 Axial E MPa In-plane E MPa In-plane PR 0.2 Transverse PR 0.2 Transverse shear 8963 MPa VF 0.6 AR Max Principal Stress (tens.) 2000 MPa Max Principal Stress (comp.) 1500 MPa Thursday, May 26, 2011 Copyright e-xstream engineering,

24 Application Example Failure analysis in Digimat-MF Principle behavior of failure in a RVE No significant difference between isotropic and transversely isotropic carbon fibers models Matrix begins to break for lower values of j for glass fibers: 30 vs. 50 for carbon fibers Values of failure are much higher for Carbon fibers Loading direction j Max. Princ. Stress in Fibers Max. Princ. Strain in Matrix Thursday, May 26, 2011 Copyright e-xstream engineering,

25 Application Example Result: von Mises stress In the Epoxy phase Layer 31 Layer 31 Min. 0 MPa Min. 0 MPa Max. 72 MPa (iso.) Max. 26 MPa (iso.) 25 MPa (trans.) Glass fibers (iso.) Carbon fibers (iso.) Thursday, May 26, 2011 Copyright e-xstream engineering,

26 Application Example Result: von Mises stress In the Fiber phase Layer 33 Layer 33 Min. 0 MPa Min. 0 MPa Max. 674 MPa (iso.) Max. 744 MPa (iso.) 793 MPa (trans.) Glass fibers (iso.) Carbon fibers (iso.) Thursday, May 26, 2011 Copyright e-xstream engineering,

27 Application Example Result: von Mises stress The value in the epoxy matrix is much more significant when using Glass fibers Danger of plasticity to occur in matrix Max. v.m. stress in epoxy matrix with Glass fibers Max. v.m. stress in epoxy matrix with Carbon fibers 71 MPa 25 MPa To be on the save side, for glass fiber reinforcement nonlinear elastoplastic modeling of the epoxy matrix can be performed with DIGIMAT Thursday, May 26, 2011 Copyright e-xstream engineering,

28 Application Example Result: Failure indicators (maximum values) Highest values are found In the epoxy matrix under tension In the fiber phase under compression Values are Critical for glass fibers under compression In general much lower for carbon fibers Isotropic Glass fibers Isotropic Carbon fibers Transversely isotropic Carbon fibers FI value Layer nr FI value Layer nr FI value Layer nr Max Epoxy tensile FI Max Epoxy compression FI Max fibers tensile FI Max fibers compression FI Thursday, May 26, 2011 Copyright e-xstream engineering,

29 Application Example Result: Maximum Principle Strain failure (tension) In the Epoxy phase Layer 31 (iso.) Layer 31 (iso.) f max =0.408 f max =0.129 Glass fibers (iso.) Carbon fibers (iso.) Thursday, May 26, 2011 Copyright e-xstream engineering,

30 Application Example Result: Maximum Principle Stress failure (compression) In the Fiber phase Layer 33 (iso.) Layer 33 (iso.) f max =0.835 f max =0.435 Glass fibers (iso.) Carbon fibers (iso.) Thursday, May 26, 2011 Copyright e-xstream engineering,

31 Application Example What happens upon switching from an isotropic to a transversely isotropic material model for the Carbon fibers? For compression failure in Epoxy and Fibers Maximum values are reached for the same layer for isotropic material model Maximum values are reached for different layers for transversely isotropic material model Values are ~30-40% higher for the transversely isotropic material model Isotropic Glass fibers Isotropic Carbon fibers Transversely isotropic Carbon fibers FI value Layer nr FI value Layer nr FI value Layer nr Max Epoxy tensile FI Max Epoxy compression FI Max fibers tensile FI Max fibers compression FI Thursday, May 26, 2011 Copyright e-xstream engineering,

32 Application Example Result: Maximum Principle Stress failure (compression) In the Carbon Fiber phase Layer 33 (iso.) Layer 1 (trans.) f max =0.435 f max =0.593 Layer 33 (trans.) f max =0.442 Thursday, May 26, 2011 Copyright e-xstream engineering,

33 DIGIMAT FOR CONTINUOUS FIBER REINFORCED COMPOSITES Summary DIGIMAT enables the coupling between processing and finite element simulation based on one unique approach to material modeling All major FEA codes accessible All major injection molding codes accessible Drapage added with version 4.2.1/4.3.1 The concept of multiscale modeling was successfully applied to design of a wind turbine blade ANSYS Composite Pre/Post was coupled with ANSYS implicit solver using DIGIMAT material description Failure was investigated on the phase level of the material It was shown that it is important to take into account transversely isotropic material models when describing carbon fibers Thursday, May 26, 2011 Copyright e-xstream engineering,

34 T h a n k y o u f o r y o u r a t t e n t i o n! w w w. e - X s t r e a m. c o m Thursday, May 26, 2011 Copyright e-xstream engineering,