24.1.1-R2 IMPACT OF AIR EVACUATION IN OUT-OF-AUTOCLAVE FLOW & COMPACTION MODELING

T.KOURKOUTSAKI (TECHNISCHE UNIVERSITÄT MÜNCHEN), S.COMAS, C.BINETRUY, R.UPADHYAY, R.HINTERHÖLZL

Due to partial impregnation and limited pressure available for curing Out-of-Autoclave prepregs, the air transport through the tows becomes applicable. Focus is given on predicting the tow fill time for through thickness resin flow taking into account the air evacuation.

24.1.1-R4 COMPRESSION FAILURE OF GRAPHENE SHEETS IN POLYMER NANOCOMPOSITES

C.ANDROULIDAKIS (UNIVERSITY OF PATRAS), E.KOUKARAS, F.OTAKAR, G.TSOUKLERI, D.SFYRIS et al.

Exfoliated graphene flakes were embedded into polymer matrices and subjected to compressive loads. By monitoring the shift of the 2D Raman band with strain, the critical strain to buckling was estimated, as well as the failure process.

24.1.1-R5 OPTIMIZATION OF PRESSURE HULLS OF COMPOSITE MATERIALS

J.FRANCO, A.CORZ (UNIVERSIDAD DE CADIZ), A.PEÑA

The pressure hull of a submarine is considered in steel and in composite. Linear buckling analysis is used to predict the feasibility of CFRP submarine pressure hull. Replacing steel by CFRP results saves up to 60% in the structural weight.

24.1.1-R6 A POWDER BASED PROCESSING ROUTE TO PRODUCE NANO AND HIERARCHICAL COMPOSITES WITH HIGH NANOFILLER LOADINGS

T.HERCEG (IMPERIAL COLLEGE LONDON), MS.ZAINOL ABIDIN, E.GREENHALGH, M.SHAFFER, A.BISMARCK

A route to manufacture hierarchical composites (HCs) based on wet powder impregnation was adapted to accommodate thermosetting matrices.

24.1.1-R7 MESO-SCALE DAMAGE MODELLING OF TEXTILE COMPOSITE USING THE EMBEDDED ELEMENT TECHNIQUE AND CONTACT ALGORITHM

S.TABATABAEI (KULEUVEN), E.BEDOGNI, D.IVANOV, SV.LOMOV

The embedded element technique was used in meso-FEM of textile composites. The effectiveness of the EE method was evaluated vs. full model in calculation of the homogenized stiffness properties and damage modelling.

24.1.2-R2 DIRECT ELECTRICAL CURE OF CARBON FIBRE COMPOSITES

S.HAYES (THE UNIVERSITY OF SHEFFIELD), P.WILSON, AD.LAFFERTY, G.ALTINKURT, M.COLLINSON et al.

Direct application of electrical current has been used to cure panels of composite in the form of flat panels or L-shaped beams. Components cured in this way are shown to have properties that are similar to conventionally cured specimens.

24.1.2-R4 EXCEPTIONAL DIELECTRIC PROPERTIES OF SELF-ALLIGNED IN-SITU REDUCED GRAPHENE OXIDE/EPOXY NANOCOMPOSITES

N.YOUSEFI, X.LIN, X.SHEN, J.JIA, JK.KIM (HONG KONG UNIVERSITY OF SCIENCE & TECHNOLOGY)

Fully-exfoliated graphene oxide sheets are uniformly dispersed to produce highly-aligned graphene/epoxy nanocomposites. The composites possess exceptional electrical conductivities and dielectric constants due to charge accumulation at the conductive filler/insulating polymer interface, which can function as excellent electromagnetic interference shielding materials

24.1.2-R5 SHEAR - COMPRESSION BUCKLING TEST METHOD ON CURVED STIFFENED COMPOSITE PANELS

F.ODERMANN (GERMAN AEROSPACE CENTER (DLR)), A.KLING

A test method is described to experimentally investigate curved stiffened composite panels with respect to their buckling and post-buckling behavior. The test method utilizes a new test rig. Results will be presented for different stiffened composite panel designs.

24.1.2-R6 CHARACTERIZATION OF MWNT/TPU SYSTEMS USING LARGE AMPLITUDE OSCILLATION

CA.GRACIA (TA INSTRUMENTS)

Interest in polymeric materials with dispersed nanotubes has increased. Rheology is used to characterize this kind of dispersions. We propose the use of large amplitude oscillation shear to characterize the dispersion/structure of a TPU matrix filled with MWCNT .

24.1.2-R7 THE EFFECT OF TECHNOLOGICAL DEFECTS ON PERFORMANCE OF FABRIC-REINFORCED COMPOSITES

AN.ANOSHKIN, DS.LOBANOV, V.MATVEENKO, A.ROY, M.TASHKINOV (PERM NATIONAL RESEARCH POLYTECHNIC UNIVERSITY) et al.

Textile composites with manufacturing and exploitation defects were studied. Analysis of deformation and damage at microscopic scale was performed to characterize the effect of such defects on materials’ response. Experimental characterization under various loading regimes was conducted using non-destructive testing.

24.1.3-R2 SIMULATION-DRIVEN TOOLING SHAPE OPTIMIZATION FOR AN EASIER ASSEMBLING PROCESS OF COMPOSITE PARTS

B.WUCHER (CENAERO), F.LANI, T.PARDOEN, C.BAILLY, D.DUMAS et al.

In this study, a generic tooling shape optimization strategy is developed. Curing simulations enable to assess the cure-induced distortions. Within an optimization loop, the mold shape is altered to reduce the discrepancy between the original design and the produced part.

24.1.3-R4 INTERFACIAL STRESS TRANSFER IN GRAPHENE-BASED NANOCOMPOSITES

R.YOUNG (UNIVERSITY OF MANCHESTER), L.GONG, I.KINLOCH, K.NOVOSELOV

The deformation of graphene nanocomposites has been investigated through the use of Raman spectroscopy. The change in the 2D Raman band shape and width during deformation has been interpreted as being due to a reversible loss of Bernal stacking.

24.1.3-R5 ASYMPTOTIC POST-BUCKLING FEM ANALYSIS OF LAMINATED COMPOSITE FOLDED PLATES

EJ.BARBERO, A.MADEO (UNIVERSITY OF CALABRIA), G.ZAGARI, R.ZINNO, G.ZUCCO

The recent developments of Koiter analysis in the context of laminated composite plates are discussed. Using a linear element within the corotational formulation the energy variations have been evaluated. The accuracy have been tested in the post-buckling analysis of clamped-box.

24.1.3-R6 COMPARATIVE STUDIES ON THE PROCESSING AND PERFORMANCE OF CARBON NANOTUBE AND NANOFIBRE BASED MULTI-SCALE COMPOSITES

S.RANA (UNIVERSITY OF MINHO), A.BIENIAŚ, S.PARVEEN, R.FANGUEIRO, R.ALAGIRUSAMY et al.

In this research, multi-scale composites based on carbon nanofibre and nanotube were fabricated and compared in terms of processing as well as in-plane mechanical, dynamic mechanical, thermal transmission, and abrasion and wear performances.

24.1.3-R7 NUMERICAL SIMULATIONS OF WOVEN COMPOSITE MATERIALS WITH VOXEL-FE MODELS

G.HELLO (UNIVERSITE D'EVRY VAL D'ESSONNE), J.SCHNEIDER, Z.ABOURA

A procedure is presented for the determination of homogenized elastic moduli from a voxel-FE description of the material architecture. The convergence of voxel-FE results and the influence of boundary conditions are studied for two typical problems.

24.1.4-R2 FACTORS OF PROCESS ROBUSTNESS IN MULTILAYER PREFORMING OF CARBON FIBRE REINFORCEMENTS

F.NOSRAT NEZAMI (MERCEDES-BENZ, SINDELFINGEN), T.GEREKE, M.HÜBNER, O.DÖBRICH, C.CHERIF

Farbod Nezami

24.1.4-R4 450% THERMAL-CONDUCTIVITY INCREASE IN SILVER-FILLED EPOXY RESINS LOADED WITH CARBON NANOTUBES AND GRAPHENE

E.MESSINA (CNR - ISTITUTO PER I PROCESSI CHIMICO FISICI), N.LEONE, C.D'ANDREA, B.FAZIO, O.MARAGO et al.

We report a simple method for dispersion of carbon Nanotubes and Graphene into a silver-filled epoxy resin, that exhibit greatly improved thermal (up to 340%) and electrical conductivity (up to 164%) without compromising the other performance aspects of the polymers.

24.1.4-R5 FAILURE ANALYSIS OF SKIN-STRINGER INTERFACES

J.REINOSO (LEIBNIZ UNIVERSITÄT HANNOVER), B.GÓMEZ, J.JUSTO, A.BLÁZQUEZ

This work addresses the analysis of a set of composite specimens that locally reproduce a blade-stiffened panel. Two different typologies were manufactured and tested following a pull-test scheme, which aimed to recreate the loading conditions corresponding to typical postbuckling patterns.

24.1.4-R6 PROTECTIVE EFFECT OF THIN ALUMINA LAYER ON CARBON FIBRE TO PRESERVE TENSILE STRENGTH DURING CNT GROWTH BY CVD

S.VOGEL (UNIVERSITY OF APPLIED SCIENCES AND ARTS NORTHWESTERN SWITZERLAND), C.DRANSFELD, B.FIEDLER, J.GOBRECHT

Carbon fibres are covered with a thin alumina layer prior to grow radially aligned carbon nano tubes on their surface, to produce hierarchical composites. The protection layer preserves the fibre tensile strength during the harsh chemical vapour deposition processing.

24.1.4-R7 SIMULATION OF THE PREFORMING STEP FOR FLAX DRY WOVEN FABRICS

C.TEPHANY (LABORATOIRE PRISME, UNIVERSITÉ D’ORLÉANS), P.OUAGNE, D.SOULAT, J.GILLIBERT

The preforming of flax dry woven fabrics, characterized by strong non linearites in tension and in-plane shear, is simulated on hemispheric shape with simple model built from elastic isotropic shells coupled to axial connectors and compared with experimental tests.