Institute for Carbon Composites
Fundamental research on material behavior, processing technology and simulation of high performance composite materials
Prof. Dr.-Ing.
n The focus of the Institute for Carbon Composites in 2014-15 was to establish and strengthen its research program within the four research groups. The main goal was to explore new ways and possibilities to reduce the process cycle time and the raw material costs to be able to implement high performance composite structures in high volume appli- cations. Different process technologies using e.g. tailored textiles and advanced matrix systems have been patented. New material models and process simulation methods have been developed and these were imple- mented in conventional software tools to enable advanced composites part and process design solutions.
Klaus Drechsler Process Technology for Fibers and Textiles
Contact
www.lcc.mw.tum.de Phone +49.89.289.15092
The Process Technology for Fibers and Textiles group focuses on improving manufacturing technologies that arrange the fibers in their desired orientation within a composite component.
The group’s three research teams cover the fields of braiding technology, automa- ted fiber placement and tailored textiles. With highly developed processing equip- ment, the fibers can be brought into shape in an automated and reproducible way.
Fiber Placement Center
Many activities in 2015 focused on the setting up of a new Fiber Placement Center at the institute’s laboratory site on the Ludwig Bölkow Campus in Taufkirchen. Three different types of fiber placement machines have been installed there to
form a unique machine park.
Machine Park
Besides a machine for the direct proces- sing of fiber tapes with thermoplastic mat- rices, an additional machine for the use
of thermoset resin tapes has been set up. This machine was moved from Garching to Taufkirchen in summer. In the course
of this relocating process it was equipped with an additional linear axis to increase the production space. Both machines are now capable of manufacturing composite parts with a length of up to 5 m. Furthermore, the Institute’s fiber patch placement system will be relocated
to Taufkirchen as well. Thus, all these
different manufacturing processes can be
Newly set up automated fiber placement cell in
Taufkirchen
usefully combined e.g. to locally reinforce big composite structures.
Collaborations
The full potential of the Fiber Placement Center for the future development of composite processing technologies
will leverage through direct interaction with research and industry partners on the campus. Especially promising are collaborations with the institute’s spin-off
companies that are also located in Taufkir- chen. These will greatly help to accelerate transferring research results into industrial applications
Public Funded Projects
n AIF project ‘3D-formbare Nassvliese’
n AIF project ‘FullCycle’ n AIF project ‘Accurat3’ n EU project ‘INSCAPE’
n BMBF project ‘MAIplast’
n BMBF project ‘MAIprofil’
n BMBF project ‘AIRCARBON II’
n BMBF project ‘MAItank’
Process Technology for Matrix Systems
The Process Technology for Matrix Systems group addresses the robust and efficient processing of matrix systems for the production of continuous fiber reinforced composite parts. On the one hand, the basic understanding of matrix systems,
the characterization of impregnation properties of the fiber material for optimized processing, and process engineering are central for the group. On the other hand, associated issues such as tool technology, surface sealing, and process integration
are key activities of the group.
Hybrid Materials and Structures –
First Prize for LCC at the AVK Innovation
Award Ceremony
The LCC won the AVK innovation award in the category ‘Research and Science’
The aim of the team is to expand the span of applications of composites. One example for this is the EU-funded project MATISSE with the main partners Autoliv, Daimler, Virtual Vehicle, TU Graz, Airborne and
TU Munich where a shape adaptive fiber-
reinforced crash structure was designed and investigated. The AVK Industrievereini- gung Verstärkte Kunststoffe e.V. honored the project with their innovation award
on 21st of september in Stuttgart in the category ‘Research and Science’.
Team Processes and Production Systems – New equipment for energy efficient processing
An industrialized microwave oven was installed in the lab of the LCC. The aim
is to develop energy-efficient processing
of fiber reinforced composites. Direct, volumetric heating and indirect heating with absorber materials is investigated to reach more optimized conditions within the production chain.
Team Tooling Systems – Successful
Project Finalization
The EU-funded project LeeTorb tested the application of self-heating tools out of CFRP for aerospace RTM processing. The consortium (Fraunhofer ICT-FIL, qpoint composite and TU Munich) was able to convince the industrial partner Airbus Helicopter of the energy efficient tool design with a full-scale tool and demonstrator part of a helicopter rotor blade.
New industrialized microwave oven at the LCC
Full-scale demonstrator tool for a helicopter rotor blade developed by the project ‘Leetorb’
Braiding process simulation of a generic structure
Simulation
Forming and Flow Process Simulation This research team works on the simulation of composite manufacturing processes. This comprises the simulation of forming technologies like draping, braiding and automated fiber placement as well as infiltration methods. Last year’s activities focused on the characterization of different materials. The goal of these investigations is to determine material properties and hence, simulation input. Finite element simulation models for draping and braiding processes were also
Public Funded Projects
n AIF project ‘HoMehr’
n BMBF project ‘FLAME’
n BMBF project ‘InFo’
n BMBF project ‘MAIplast’
n BMBF project ‘MAIfo’
n BFS project ‘FORCiM3A’
n BFS project ‘TIP’
n EU project ‘Disacop’
n EU project ‘LeeTorb’
developed and validated. The validation consisted of comparing simulation to experimental results.
Compaction, Curing and
Consolidation Simulation
Research efforts in this team are dedica- ted to modeling of cure induced effects on the final part’s properties and appearance with a focus on compaction behavior and porosity content, thermal management
and process induced deformations. In
2015, implementation and validation has been concluded for modeling the thermal management of large scale resin transfer molded aerospace structures as well as the consolidation of out-of-autoclave prepregs. Magnitude and shape of global deformation modes identified experi- mentally for a spar structure (featuring a
material with engineered vacuum channels and manufactured with a caul) were
found to significantly differ from simulated deformations, demanding more detailed process modeling of complex structures. To tackle this issue and gain further
insight in the importance of compaction and resin flow related phenomena on the part’s quality, future activities will focus
on transferring modeling capabilities from lamina level to arbitrary three-dimensional
manufacturing setups.
Out-of-autoclave consolidation - validation of a stochastic approach for initial degree of impregnation modeling
Material Modeling and Structural
Analysis
The Material Modeling and Structural Analysis research team focuses on the structural analysis of fiber reinforced plastics as well as mechanical and bonded joints at different length scales.
One research focus is the prediction of the constitutive behavior of textile-reinforced composites using unit cells. A framework
is proposed predicting the non-linear mechanical response of triaxial braided composites using mesoscopic finite element unit cells. In order to capture the predominant failure modes observed in braided composites, the model comprises a physically based damage model inside the yarns, plasticity in the resin pockets, and delamination at the yarn-matrix interfaces.
Another research area consists of the
non-linear behavior of angle-ply laminates. A constitutive model for composite lami- nates is developed with the focus on the distinction between inducing mechanisms. It is shown, that the effect of fiber rotation and damage is essential in consideration of large deformations. To ensure the appli- cability to structural parts, the numerical model is validated by a large number of
various angle-ply tension and off-axis compression tests, fabricated of the same carbon/epoxy IM7-8552 material.
Public Funded Projects
n DFG project ‘DR 204/5-1, G8’
n STMWIVT project ‘ComBo’ n BMBF project ‘MAIdesign’ n BMBF project ‘transhybrid’ n BMBF project ‘MAIprofil’
n BMBF project ‘MAIform’
n BMBF project ‘MAITAI’
n BMBF project ‘MAIhiras+handle’
n BFS project ‘FORCiM3A’
n EU project ‘LeeTorb’
Roadmap and data flow for gene- rating a realistic unit cell model for braided composite materials
Material Behavior and Testing
The Material Behavior and Testing group focuses on the investigation of the material response of fiber-reinforced polymer
matrix composites.
At the testing laboratories of the LCC a broad spectrum of state-of-the-art test methods and equipment is available, covering thermo-analytical methods,
rheology and microscopy, experimental methods to measure permeability and drapability of UD and textile preforms, as well as static and high strain rate mecha- nical testing.
An important focus of the group is on the area of high strain rate testing, where split Hopkinson bars for compression, tension
Four-point bending test (left) and double-cantilever-beam (DCB) mode I fracture toughness test (right) performed at static loading.
High strain rate UD glass-epoxy tension specimen installed in split-Hopkinson tension bar (SHTB).
and torsional loading, installed in 2012 and 2013, are used to reach strain rates of up to 1000 s-1.
In 2014 and 2015 various aerospace com- posite materials were investigated under tension and compression loads at impact rates of strain (bird strike scenario). Recently the focus is on the development and testing of high strength tension specimens (e.g. UD glass-fiber composite and fiber-metal laminates) as well as the investigation of the fracture toughness properties of composite materials.
Research Focus
n Process technology for fibers and
textiles
n Process technology for matrix systems
n Simulation
n Material behavior and testing
Competence
The LCC takes an interdisciplinary approach to research, extending from raw materials through implementation of manufacturing technologies to complete composite components. With specially developed simulation methods, the composite manufacturing process chain can be represented virtually.
Infrastructure
n Composite technical lab ‘Preforming and Thermoset Injection Technology’
n Composite technical lab ‘Thermoplastic
Technology’
n Composite test labor
n Computing cluster
Failure envelope for combined compression-shear loading of 5-harness-satin weave carbon-epoxy at static loading (qs) and high strain rates of 200 s-1 (ir) and 1000 s-1 (hr) [Koerber et al. Int J Solids Struct 54,
2015].
Courses
n Materials and Process Technologies for
Carbon Composites
n Composite Materials and Structure- property Relationship
n Analysis and Design of Composite
Structures
n Production Technologies for Composite
Parts
n Process Simulation and Material
Modeling of Composites
n Carbon and Graphite – High Perfor- mance Materials for Key Industries
n Supply Chain and Value Creation
Composites
Management
Prof. Dr.-Ing. Klaus Drechsler, Director
Dr. mont. Elisabeth Ladstätter
Adjunct Professors
Dr.-Ing. Oswin Öttinger
Dr.-Ing. Christian Weimer
Administrative and Technical Staff
Cigdem Filker Diana Zinke Gabriele Uruk
Daniel Amrein, B.Sc.
Helmut Josef Dick Georg Lerchl Thomas Witteczek Reiner Rauch
Research Scientists
Dipl.-Ing. Andreas Altmann Luciano Avila Gray, M.Sc. Dipl.-Ing. Paul Bockelmann Dipl.-Ing. Philipp Bruckbauer Dipl.-Ing. Christoph Ebel
Dipl.-Ing. Ludwig Eberl Dipl.-Ing. Stefan Ehard Dipl.-Ing. Ralf Engelhardt Dipl.-Ing. Philipp Fahr Dipl.-Ing. Petra Fröhlich Thorsten Gröne, MBA Dipl.-Ing. Thorsten Hans
Dipl.-Des. Benjamin Hansbauer
Dipl.-Ing. Tobias Harbers Dipl.-Ing. Mathias Hartmann Rhena Helmus, M.Sc
Dr. techn. Roland Hinterhölzl Dipl.-Ing. Philipp Hörmann Dipl.-Ing. Bernhard Horn
Dipl.-Ing. Philipp Kammerhofer
Dipl.-Ing. Kalle Kind
Dipl.-Ing. Andreas Kollmannsberger
Dr. Hannes Körber
Theodosia Kourkoutsaki, M.Sc.
Dipl.-Ing. Jan Krollmann Peter Kuhn, M.Sc. Christian Lemke, M.Sc.
Dipl.-Ing. Roland Lichtinger Dipl.-Ing. Dr. Neven Majic Dipl.-Ing. Ulrich Mandel Alexane Margossian, M.Sc.
Dipl.-Tech. Math. Natalie Mayer
Dipl.-Ing. Reinhold Meier
Dipl.-Ing. Felix Michl
Dipl.-Ing. Andreas Mierzwa Dipl.-Ing. Maximilian Mitwalsky Dipl.-Ing. Johannes Neumayer Jonathan Oelhafen, M.Sc.
Dipl.-Ing. Philipp Picard
Marina Plöckl, M.Sc.
Dipl.-Ing. Veronika Radlmaier
Dipl.-Ing. Maximilian Schäfer
Dipl.-Ing. Philipp Maximilian Schäfer
Dipl.-Ing. David Schultheiß
Dipl.-Ing. Alexander Schwingenschlögl
Dipl.-Ing. Robin Taubert
Dipl.-Ing. Daniel Teufl
Dipl.-Ing. Tobias Wehrkamp-Richter
Dipl.-Ing. Jakob Weiland
Dipl.-Ing. Thomas Wettemann
Dipl.-Ing. Swen Zaremba
Publications 2015
n Altmann, A.; Gesell, P.; Drechsler, K.: Strength prediction of ply waviness in composite materials considering matrix dominated effects. Composite Structures 127, 2015, 51-59
n Altmann, A.; Taubert, R.; Mandel, U.; Hinterhölzl, R.;
Drechsler, K.: A continuum damage model to pre- dict the influence of ply waviness on stiffness and strength in ultra-thick unidirectional fiber-reinforced plastics. Journal of Composite Materials, 2015
n Arnold, M.; Henne, M.; Bender, K.; Drechsler, K.:
Polyamide 12 modified with nanoparticles: effect on impact behaviour and on the electrical conductivity of carbon fibre-reinforced epoxy composites. Journal of Composite Materials, 2015
n Fischer, B.; Horn, B.; Bartelt, C.; Blößl, Y.: Method
for an Automated Optimization of Fiber Patch Placement Layup Designs. International Journal of Composite Materials Vol. 5 (No. 2), 2015, pp. 37-46
n Hans, T.; Cichosz, J.; Brand, M.; Hinterhölzl, R.:
Finite element simulation of the braiding process for arbitrary mandrel shapes. Composites Part A: Applied Science and Manufacturing, 2015
n Helmus, R.; Centea, T.; Hubert, P.; Hinterholzl, R.:
Out-of-autoclave prepreg consolidation: Coupled air evacuation and prepreg impregnation modeling. Journal of Composite Materials, 2015
n Helmus, R.; Hinterhölzl, R.; Hubert, P.: A Stochastic
Approach to Model Material Variation Determining Tow Impregnation in Out-of-Autoclave Prepreg Consolidation. Composites Part A: Applied Science and Manufacturing, 2015
n Kourkoutsaki, T.; Comas-Cardona, S.; Binetruy, C.;
Upadhyay, R.K.; Hinterhoelzl, R.: The impact of air evacuation on the impregnation time of out-of- autoclave prepregs. Composites Part A: Applied Science and Manufacturing 79, 2015, 30-42
n Körber, H.; Xavier, J.; Camanho, P.P.; Essa, Y.E.;
Martín de la Escalera, F.: High strain rate behaviour of 5-harness-satin weave fabric carbon-epoxy composite under compression and combined compression-shear loading. International Journal of Solids and Structures, 2015