24.2.1-R1 FUNCTIONALLY GRADED BOND-LINES FOR METAL/COMPOSITE JOINTS

R.BRETO (ARAGON INSTITUTE OF TECHNOLOGY), A.CHIMINELLI, E.DUVIVIER, M.LIZARANZU, MA.JIMÉNEZ

The present work is focused on ‘functionally graded adhesive joints’ for aluminium/composite substrates. A bondline with a variation of the adhesive properties is optimized and tested in order to improve the strength of a single lap joint under shear loads.

24.2.1-R2 QUANTIFICATION OF LOCAL FIBER DISTRIBUTION FOR OPTIMIZATION OF TAPE LAYING TECHNIQUES

T.GUGLHOER (UNIVERSITY OF AUGSBRUG), F.MANGER, M.SAUSE

An image processing method is proposed to quantify local fiber volume fractions on different length scales in unidirectional fiber reinforced composites. Applying the method to micrographs indicates a correlation between fiber reinforced Polyamide-6 tapes and corresponding laminates.

24.2.1-R3 TENSILE BEHAVIORS AND FRACTURE CHARACTERISTICS OF LAMINATED TI6AL4V-TIBW/TI6AL4V COMPOSITES ALONG TRANSVERSE AND LONGITUDINAL DIRECTIONS

B.LIU (HARBIN INSTITUTE OF TECHNOLOGY), L.HUANG, B.WANG, L.GENG

laminated Ti6Al4V-TiBw/Ti6Al4V composites was successfully fabricated by reaction hot pressing,TiB whiskers and their network distribution change matrix microstructure, The longitudinal elongation and the ultimate strength increased to 12.5% and 1120MPa, whereas the transverse properties reach to 7.8% and 1020MPa, respectively.

24.2.1-R4 THERMAL CONDUCTIVITY OF GNP/EPOXY NANOCOMPOSITES AND THEIR APPLICATION AS THERMAL INTERFACE MATERIALS

R.MORICHE TIRADO (UNIVERSITY REY JUAN CARLOS), SG.PROLONGO, M.SÁNCHEZ, A.JIMÉNEZ-SUÁREZ, A.UREÑA

Graphene is known to have a high thermal conductivity (5000 W/mK) constituting a potential material applicable in heat dissipation as thermal interface material (TIM). Thermal diffusivity in GNP/epoxy nanocomposites is amplified a 210% with an 8 wt%.

24.2.1-R5 THE INFLUENCE OF AUTOCLAVING PROCESS PARAMETERS ON LOAD CARRYING-CAPACITY OF THIN-WALLED CHANNEL SECTION COLUMNS

J.BIENIAŚ, P.JAKUBCZAK, T.KUBIAK (LODZ UNIVERSITY OF TECHNOLOGY), K.MAJERSKI

The material properties of laminates depends on the parameters of autoclaving process. The authors have decided to check and show the influence of time and temperature of the process of production the thin-walled composite C shape beam-columns on carrying-capacity load.

24.2.1-R6 FABRICATION AND PROPERTIES OF POLYMER NANOCOMPOSITES BASED ON CARBON NANOTUBES PREPREGS

G.TRAKAKIS (INSTITUTE OF CHEMICAL ENGINEERING SCIENCES (ICE-HT), GREECE), D.TASIS, J.PARTHENIOS, C.GALIOTIS, K.PAPAGELIS

Polymer nanocomposites have been produced by carbon nanotube prepregs. Firstly, buckypapers have been produced, characterized and optimized for prepreg production, and then nanocomposites were produced by autoclave processing. The mechanical, thermal and electrical properties of the nanocomposites were studied.

24.2.1-R7 VERIFICATION OF FLOWTEX SOLVER USING ANSYS CFX - EXAMINING THE PERMEABILITY PREDICTION METHOD ON A RANGE OF TEXTILE ARCHITECTURE MODELS

E.SWERY (THE UNIVERSITY OF AUCKLAND), R.MEIER, SV.LOMOV, C.HAHN, P.KELLY et al.

This paper compares the predicted permeability values of the same textile models obtained using FlowTex and Ansys CFX solvers. A study was also conducted on textile models based on the second permeability benchmark exercise comparing to experimental results.

24.2.2-R1 NUMERICAL INVESTIGATION ON THE STRUCTURAL MECHANICS OF A JOINING TECHNIQUE FOR COMPOSITE MATERIALS: THE REDUNDANT HIGH EFFICIENCY ASSEMBLY

H.LANG (FRAUNHOFER ICT), AC.NOGUEIRA, M.JÜRGENS, E.HOMBERGSMEIER, K.DRECHSLER

This paper deals with an interlaminar reinforcement for bonded composite structures, which is based on the implementation of metallic three-dimensionally bent elements on meso-scale. The influence of design parameters on the mechanics of the joint is analyzed with numerical investigations.

24.2.2-R2 MECHANICAL PROPERTY AND FLOWABILITY OF QUASI-ISOTROPIC UACS LAMINATES

Y.FUJITA (TORAY INDUSTRIES, INC), H.MATSUTANI, S.KAWAMOTO, T.TAKEHARA, I.TAKETA

UACS is a sheet-like molding material made by regularly introducing slits into a conventional prepreg.UACS achieves both distinguished mechanical properties and excellent flowablity during molding.In this study, several mechanical tests were carried out to determine distinct characteristics of UACS.

24.2.2-R3 MICROSTRUCTURE AND MECHANICAL PROPERTIES OF MULTI-WALLED CARBON NANOTUBE/ALUMINA COMPOSITES PREPARED BY A NOVEL FLOCCULATION METHOD

W.WANG (TOHOKU UNIVERSITY), G.YAMAMOTO, K.SHIRASU, Y.NOZAKA, T.HASHIDA

The MWCNT/alumina composites with a high volume fraction of nanotubes were prepared. A novel flocculation method combined with acid treatment and SPS avoided the MWCNT segregation and degradation, realizing the maintenance and increase of bending strength and fracture toughness successfully.

24.2.2-R4 COMPOSITE HYDROGELS BASED ON SILK FIBROIN REINFORCED WITH CARBON NANOTUBES AND/OR GRAPHENES FOR TISSUE ENGINEERING APPLICATIONS

C.ZAHARIA (UNIVERSITY POLITEHNICA OF BUCHAREST), PO.STANESCU, B.GALATEANU, E.VASILE, MA.PANDELE et al.

This paper focuses on the development of silkworm fibroin/polyacrylamide/carboxylated MWCNTs hydrogels as biomimetic materials to support the biomineralization process. Hydrogels were obtained by free radical polymerization of acrylamide and methylenebisacrylamide in silk fibroin solutions containing dispersed carboxylated multiwall carbon nanotubes.

24.2.2-R5 BUCKLING ANALYSIS OF COMPOSITE PLATES UNDER COMBINED LOADING, WITH ACCOUNT OF BENDING-TWISTING COUPLING

S.SELYUGIN (AIRBUS-GERMANY)

Buckling of composite flexurally-anisotropic plates under combined loading is considered. Regularities inherent in the phenomenon are explored and described. Several approaches to buckling eigen value calculation are proposed. The approaches are based on use of buckling results for separate loadings.

24.2.2-R6 CARBON NANOTUBES/NANOFIBERS COMPOSITES FROM CELLULOSE FOR SUPERCAPACITORS

V.KUZMENKO, AM.SALEEM, O.NABOKA, H.STAAF, P.ENOKSSON (WALLENBERG WOOD SCIENCE CENTER, CHALMERS UNIVERSITY OF TECHNOLOGY) et al.

Cellulose-based carbon nanofibers with high mechanical strength and electrochemical stability were nitrogen-doped and functionalized with carbon nanotubes via two different methods. As a result, the composite materials with capacitance values up to 241 F/g were obtained.

24.2.2-R7 MULTI-SCALE MODELING AND ESTIMATION OF DAMAGE DEVELOPMENT FOR TEXTILE COMPOSITES CONSIDERING MESO/MICRO SCALE STRUCTURES

T.KURASHIKI (OSAKA UNIVERSITY), Y.MATSUSHIMA, K.IKUTA, H.KIKUCHI, S.HIROSAWA et al.

An individual modeling method for meso-scale structure of textile composites has been developed. In the case of 3D woven composites, the models of matrix and fabric parts are generated independently. The damage development under static loading has been investigated.

24.2.3-R1 EXPERIMENTAL AND NUMERICAL STUDY OF THE MOISTURE DIFFUSION IN ADHESIVE COMPOSITE JOINTS

L.CANAL, R.SARFARAZ, G.VIOLAKIS, V.MICHAUD (EPFL), J.BOTSIS et al.

We measured water diffusion into adhesively bonded composite joints, pure adhesive and monolithic composite. FBG sensors were used to detect the swelling strain. A Finite Element model simulated water diffusion into the joint and the strain response with good agreement.

24.2.3-R2 REINFORCEMENT OF PARTIALLY CURED AEROSPACE STRUCTURES WITH B-STAGED PATCHES

J.STUDER, K.MASANIA (UNIVERSITY OF APPLIED SCIENCES AND ARTS NORTHWESTERN SWITZERLAND), C.DRANSFELD

This research implements analytical models to create partially cured CFRP structures that can be locally reinforced for bearing loads. Failure could be delayed using the B-stage reinforcement co-cure solution that is proposed, and double with the use of steel interlayers.

24.2.3-R3 DAMAGE OF AA2124/SIC METAL MATRIX COMPOSITE UNDER FATIGUE CONDITIONS

A.RUTECKA (INSTITUTE OF FUNDAMENTAL TECHNOLOGICAL RESEARCH OF THE POLISH ACADEMY OF SCIENCES), P.GUTKIEWICZ, P.GRZYWNA, L.DIETRICH

Fatigue tests of AA2124 based metal matrix composites (MMCs) with SiC particles reinforcement were carried out. Hysteresis loops were observed during subsequent cycles. Cyclic plasticity and ratcheting were identified as main fatigue damage mechanisms.

24.2.3-R4 EFFECTS OF GRAPHENE OXIDE ON MOLECULAR DYNAMICS, THERMAL AND MECHANICAL PROPERTIES OF POLY(L-LACTIC ACID)

P.KLONOS (NATIONAL TECHNICAL UNIVERSITY OF ATHENS, GREECE), G.PAPAGEORGIOU, Z.TERZOPOULOU, K.TRIANTAFYLLIDIS, D.GOURNIS et al.

A variety of experimental techniques were employed to study structure and morphology, thermal transitions, molecular mobility, mechanical properties, and biodegradation in poly(l-lactic acid)/ graphene oxide nanocomposites. The results suggest strong polymer-filler interactions.

24.2.3-R5 A NEW DESIGN CONCEPT FOR CYLINDRICAL COMPOSITE SHELLS UNDER AXIAL COMPRESSION

R.WAGNER (GERMAN AEROSPACE CENTER), C.HÜHNE

In this Paper, the advanced Single-Perturbation Load approach for the design of thin-walled unstiffened composite cylindrical shells is proposed. The new apporach delivers on average 40 % larger knock-down factors compared to existing guidelines like the NASA SP-8007.

24.2.3-R6 MOLECULAR SIMULATION FOR PREDICTING MECHANICAL STRENGTH OF 3-D JUNCTIONED CARBON NANOSTRUCTURES

S.SIHN (UNIVERSITY OF DAYTON RESEARCH INSTITUTE), V.VARSHNEY, AK.ROY, BL.FARMER

We have predicted the mechanical strength of various carbon nanostructures including carbon nanotubes (CNTs), graphene, CNT with defects and CNT-graphene junctioned nanostructures under various loading modes based on combined molecular mechanics and molecular dynamics simulations.

24.2.3-R7 OPTIMISATION OF THE PROCESS PARAMETERS TO PREVENT THE APPEARANCE OF DEFECTS DURING THE COMPLEX SHAPE FORMING OF FLAX BASED REINFORCEMENTS

E.CAPELLE, P.OUAGNE (UNIVERSITÉ ORLEANS), D.SOULAT, S.GUERET

Solutions to preform complex shapes such as a tetrahedron without any defect from flax based woven fabrics are investigated in this work. Particularly the ones based on the optimisation of the process parameters gave successful results.

24.2.4-R1 BONDING OF CFRP PRIMARY AEROSPACE STRUCTURES - DISCUSSION OF THE CERTIFICATION BOUNDARY CONDITIONS AND RELATED TECHNOLOGY FIELDS ADRESSING THE NEEDS FOR DEVELOPMENT

TA.SCHMID-FUERTES (AIRBUS OPERATIONS), T.KÖRWIEN, M.GEISTBECK, T.KRUSE

An overview of the state of the art certification for bonded Aerospace CFRP primary structures is given and the role of different technologys like surface preparation, process capability, material development, design concepts to enable a roadmap to certification is discussed.

24.2.4-R2 THE ECONOMICS OF THROUGH-THICKNESS FIBRE REINFORCEMENT USING SINGLE SIDED ROBOTIC TUFTING

D.HARMAN, S.GROVE (PLYMOUTH UNIVERSITY), J.SUMMERSCALES

Manufacturing cost, performance and weight are studied for tufted and non-tufted NCF and prepreg for a generic T-post. The through-life cost benefit of a lower mass solution is almost 17% lower than the current prepreg solution.

24.2.4-R3 COMPOSITE OXIDE FIBRES

S.MILEIKO (INSTITUTE OF SOLID STATE PHYSICS OF RAS), A.KOLCHIN, N.NOVOKHATSKAYA, V.KIIKO, I.NOVIKOV

A method to produce oxide fibres composed of sapphire matrix and calcium hexaaluminate inclusions, which serve as a “weak” substance to arrest the microcrack in a brittle matrix. The fibre can be used to make non-brittle composites containing brittle components.

24.2.4-R4 FUNCTIONALIZATION OF GRAPHITE OXIDE SHEETS AS A TOOL FOR THE PREPARATION OF ELECTRICAL CONDUCTIVE POLYMER/GRAPHITE OXIDE COMPOSITES

E.BEYOU (UNIVERSITE LYON1), G.ALINE, P.CASSAGNAU, M.GREGORY, P.SONNTAG

The preparation of polymer/GO composites exhibiting rheological and electrical percolation thresholds has been done through covalent functionalization of polymer-decorated graphite oxide (GO) sheets. This chemical functionalization also influences solubility behaviour of the formed polymer grafted GO sheets in various solvents

24.2.4-R6 THREE-DIMENSIONAL PERMEABILITY DETERMINATION OF REINFORCED COMPOSITES STRUCTURES WITH VERTICALLY ALIGNED CARBON NANOTUBE FORESTS

L.CHEVALLIER (UNIVERSITÉ DE TOULOUSE, MINES ALBI), Q.GOVIGNON, P.OLIVIER, G.BERNHART, J.BOUILLONNEC et al.

By processing aligned carbon nanotube-reinforced composites, Clément Ader Institute intends to exploit their oustanding mechanical properties for ballistic applications. Vaccum Assisted Transfer Molding (VARTM) process requires a preliminary three-dimensionnal permeability determination to provide optimal operating conditions.

24.2.4-R7 NEW APPROACH FOR THE CONSTRUCTION OF MESO-SCALE FINITE ELEMENT MODELS OF TEXTILE COMPOSITES WITH PERIODIC BOUNDARY CONDITIONS

S.JACQUES (GHENT UNIVERSITY), I.DE BAERE, W.VAN PAEPEGEM

The new ORAS software allows non-identical meshes at opposite faces and multiple part meshes for implementing PBC. The homogenized results of the meso-scale FE analysis of the RUC obtained with ORAS correlate with those of conventional techniques and experimental data.