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Pupurs, A., Loukil, M., Marklund, E., Varna, J. & Mattsson, D. (2024). Transverse Crack Initiation in Thin-Ply Laminates Subjected to Tensile Loading at Low and Cryogenic Temperatures. Mechanics of composite materials, 59(6), 1049-1064
Åpne denne publikasjonen i ny fane eller vindu >>Transverse Crack Initiation in Thin-Ply Laminates Subjected to Tensile Loading at Low and Cryogenic Temperatures
Vise andre…
2024 (engelsk)Inngår i: Mechanics of composite materials, ISSN 0191-5665, E-ISSN 1573-8922, Vol. 59, nr 6, s. 1049-1064Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Laminates with ultra-thin plies is a promising new development for polymeric composite materials expected to provide superior resistance to intralaminar crack propagation. The ply thickness effect on the crack initiation stress that according to some theoretical studies on fiber/matrix debonding does not depend on the ply thickness was investigated. Ultra-thin ply carbon fiber/epoxy cross-ply laminates subjected to tensile loading at room, –50, and –150°C temperatures relevant for cryogenic fuel storage, aeronautical, and aerospace applications were studied. The stochastic nature of the crack initiation stress in the 90°-plies was analyzed using Weibull strength distribution. The results obtained show delayed transverse crack initiation only in the thinnest plies with a clear trend that the scale parameter is much larger. This thickness effect on initiation is different than that for crack propagation which is observable in much larger ply thickness range. Regarding crack propagation, it was found that in most cases even at very high applied strain levels (1.5%) only a few transverse cracks have propagated from the specimen edges to its middle. 

sted, utgiver, år, opplag, sider
Springer, 2024
Emneord
cryogenic temperatures, experimental testing, thin-ply laminates, transverse cracking, Aerospace applications, Carbon fibers, Crack propagation, Fuel storage, Laminated composites, Tensile stress, Weibull distribution, Cracks initiations, Cracks propagation, Ply laminates, Ply thickness, Tensile loading, Thin-ply laminate, Transverse crack, Stochastic systems
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-71964 (URN)10.1007/s11029-023-10156-0 (DOI)2-s2.0-85181248582 (Scopus ID)
Forskningsfinansiär
EU, FP7, Seventh Framework Programme, No.1.1.1.2/VIAA/3/19/408
Merknad

This work was supported by the European Regional Development Fund within the Activity 1.1.1.2 “Post-doctoral Research Aid” of the Specifc Aid Objective 1.1.1 “To increase the research and innovative capacity of scientifc institutions of Latvia and the ability to attract external fnancing, investing in human resources and infrastructure” of the Operational Programme “Growth and Employment” (No.1.1.1.2/VIAA/3/19/408). The authors would also like to acknowledge research project “Cryogenic Hypersonic Advanced Tank Technologies (CHATT)” coordinated by DLRSART and funded by the EU within the 7th Framework Programme Theme 7 Transport. Experimental work of Mr. Hugo Scaglia is greatly acknowledged.

Tilgjengelig fra: 2024-02-26 Laget: 2024-02-26 Sist oppdatert: 2024-02-26bibliografisk kontrollert
Singh, V., Larsson, R., Olsson, R. & Marklund, E. (2023). A micromechanics based model for rate dependent compression loaded unidirectional composites. Composites Science And Technology, 232, Article ID 109821.
Åpne denne publikasjonen i ny fane eller vindu >>A micromechanics based model for rate dependent compression loaded unidirectional composites
2023 (engelsk)Inngår i: Composites Science And Technology, ISSN 0266-3538, E-ISSN 1879-1050, Vol. 232, artikkel-id 109821Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Strain-rate effects in a unidirectional non-crimp fabric carbon/epoxy composite are addressed. To allow for kink-band formation including strain-rate effects and damage in such composites, the paper advances a recent model focused on compression loading at small off-axis angles. The model is based on computational homogenization with a subscale represented by matrix and fibre constituents at finite deformation. The fibre constituent is assumed to be elastic transversely isotropic and the matrix is viscoelastic–viscoplastic with damage degradation. Novel model improvements of special importance to small off-axis loading relate to the isostress formulation of the homogenized response in transverse shear. In this context, an enhanced homogenized elastic response is proposed based on Halpin–Tsai corrections to account for the nonuniform stress distribution on the microscale. The model captures the strongly rate sensitive kink-band formation due to localized matrix shearing and fibre rotation, confirming the experimentally observed increase in compressive strength for high strain rates. © 2022 The Author(s)

sted, utgiver, år, opplag, sider
Elsevier Ltd, 2023
Emneord
A. Structural composites, B. Non-linear behaviour, C. Damage mechanics, C. Material modelling, Viscoelasticity–viscoplasticity, Compressive strength, Strain rate, A structural composite, B non-linear behavior, C damage mechanic, C material modeling, Damage-mechanics, Material modeling, matrix, Nonlinear behaviours, Structural composites, Viscoelasticity
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-61350 (URN)10.1016/j.compscitech.2022.109821 (DOI)2-s2.0-85142492701 (Scopus ID)
Merknad

 Funding details: University of Patras; Funding details: H2020 Marie Skłodowska-Curie Actions, MSCA, 721256; Funding details: Stiftelsen för Strategisk Forskning, SSF, FID16-0041, P113521, SK-projects P108811; Funding text 1: The model development was funded by the Swedish Foundation for Strategic Research (SSF, dnr FID16-0041), with co-funding from RISE internal development funds, Sweden (SK-projects P108811 and P113521). The experiments were funded by the ICONIC project under the Marie Skłodowska-Curie, Sweden grant No 721256. G. Lampeas and B. Ravindran at University of Patras are acknowledged for assistance with experimental data, which allowed us to validate our model.; Funding text 2: The model development was funded by the Swedish Foundation for Strategic Research ( SSF, dnr FID16-0041 ), with co-funding from RISE internal development funds, Sweden (SK-projects P108811 and P113521). The experiments were funded by the ICONIC project under the Marie Skłodowska-Curie, Sweden grant No 721256 . G. Lampeas and B. Ravindran at University of Patras are acknowledged for assistance with experimental data, which allowed us to validate our model.

Tilgjengelig fra: 2022-12-09 Laget: 2022-12-09 Sist oppdatert: 2023-06-07bibliografisk kontrollert
Singh, V., Larsson, R., Olsson, R. & Marklund, E. (2023). Rate dependent compressive failure and delamination growth in multidirectional composite laminates. Journal of composite materials
Åpne denne publikasjonen i ny fane eller vindu >>Rate dependent compressive failure and delamination growth in multidirectional composite laminates
2023 (engelsk)Inngår i: Journal of composite materials, ISSN 0021-9983, E-ISSN 1530-793XArtikkel, forskningsoversikt (Fagfellevurdert) Epub ahead of print
Abstract [en]

A novel intralaminar model has, for the first time, been applied and validated for the rate-dependent failure of multidirectional carbon/epoxy laminates. Quasi-static compressive failure is evaluated by the growth of intralaminar rate-dependent damage combined with the interaction of cohesive zones for interlaminar delamination. A special feature of the intralaminar model is the homogenised ply response, allowing simultaneous damage-degradation of the polymer matrix combined with the fibres. To model the observed quasi-brittle failure response of the plies under finite deformation, we have used a viscoelastic-viscoplastic matrix combined with damage and isotropic hardening behaviour. Elastic transverse isotropy is used to model the fibre reinforcement of the plies. Standard cohesive surfaces are used to model the initiation and propagation of delamination. Numerical simulations using ABAQUS/Explicit are performed to predict the growth and delamination of intralaminar damage under compression in different laminates with 56 plies of IM7/8552 carbon/epoxy. Predictions of stress versus strain and damage growth are shown to agree well with experimental results for a range of strain rates and stacking sequences. 

sted, utgiver, år, opplag, sider
SAGE Publications Ltd, 2023
Emneord
Brittle fracture; Carbon; Ductile fracture; Hardening; Laminated composites; Strain rate; Viscoplasticity; Angle ply laminate; Cohesive surface; Composite laminate; Compressive failure; Continuum damage; Delamination growth; Dependent failure; Isotropic hardenings; Rate dependent; Viscoelasticity-viscoplasticity; Viscoelasticity
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-68794 (URN)10.1177/00219983231215688 (DOI)2-s2.0-85178417981 (Scopus ID)
Forskningsfinansiär
Swedish Foundation for Strategic Research, FID16-0041
Merknad

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the Swedish Foundation for Strategic Research (SSF) through the contract dnr FID16-0041 and by the internal SK-development funds of RISE.

Tilgjengelig fra: 2024-01-10 Laget: 2024-01-10 Sist oppdatert: 2024-01-15bibliografisk kontrollert
Larsson, R., Singh, V., Olsson, R. & Marklund, E. (2022). A micromechanically based model for dynamic damage evolution in unidirectional composites. International Journal of Solids and Structures, 238, Article ID 111368.
Åpne denne publikasjonen i ny fane eller vindu >>A micromechanically based model for dynamic damage evolution in unidirectional composites
2022 (engelsk)Inngår i: International Journal of Solids and Structures, ISSN 0020-7683, E-ISSN 1879-2146, Vol. 238, artikkel-id 111368Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

This article addresses the micromechanically motivated, quasistatic to dynamic, failure response of fibre reinforced unidirectional composites at finite deformation. The model draws from computational homogenization, with a subscale represented by matrix and fibre constituents. Undamaged matrix response assumes isotropic viscoelasticity–viscoplasticity, whereas the fibre is transversely isotropic hyperelastic. Major novelties involve damage degradation of the matrix response, due to shear in compression based on a rate dependent damage evolution model, and the large deformation homogenization approach. The homogenized quasi-brittle damage induced failure is described by elastically stored isochoric energy and plastic work of the undamaged polymer, driving the evolution of damage. The developed model is implemented in ABAQUS/Explicit. Finite element validation is carried out for a set of off-axis experimental compression tests in the literature. Considering the unidirectional carbon–epoxy (IM7/8552) composite at different strain rates, it appears that the homogenized damage degraded response can represent the expected ductile failure of the composite at compressive loading with different off-axes. Favourable comparisons are made for the strain and fibre rotation distribution involving localized shear and fibre kinking. © 2021 The Authors

sted, utgiver, år, opplag, sider
Elsevier Ltd, 2022
Emneord
Continuum damage, Homogenization, Off-axis compression loading, Unidirectional ply, Viscoplasticity, ABAQUS, Compression testing, Deformation, Plasticity, Strain rate, Compression loading, Damage evolution, Dynamic damage, matrix, Off-axis, Unidirectional composites, Fibers
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-57498 (URN)10.1016/j.ijsolstr.2021.111368 (DOI)2-s2.0-85121235543 (Scopus ID)
Merknad

Funding details: 721256; Funding details: Stiftelsen för Strategisk Forskning, SSF, 25201, FID16-0041; Funding details: VINNOVA, 2016-04239; Funding details: Horizon 2020; Funding text 1: The authors gratefully acknowledge the support of the ICONIC project under the Marie Skłodowska-Curie grant agreement No 721256 of the European Union Horizon 2020 research and innovation programme . Co-funding has also been provided from the Swedish FFI programme via VINNOVA (dnr 2016-04239 ), SSF, Sweden (dnr FID16-0041 ) and from the development funds of RISE, Sweden (RISE SICOMP SK-project 25201).

Tilgjengelig fra: 2021-12-30 Laget: 2021-12-30 Sist oppdatert: 2023-06-07bibliografisk kontrollert
Larsson, R., Singh, V., Olsson, R. & Marklund, E. (2020). A micromechanically based model for strain rate effects in unidirectional composites. Mechanics of materials, 148, Article ID 103491.
Åpne denne publikasjonen i ny fane eller vindu >>A micromechanically based model for strain rate effects in unidirectional composites
2020 (engelsk)Inngår i: Mechanics of materials, ISSN 0167-6636, E-ISSN 1872-7743, Vol. 148, artikkel-id 103491Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

This article addresses dynamic behaviour of fibre reinforced polymer composites in terms of a transversely isotropic viscoelastic-viscoplastic constitutive model established at the unidirectional ply level. The model captures the prelocalized response of the ply in terms of rate dependent elasticity and strength without damage. A major novelty is that the model draws from computational homogenization, with matrix and fibre materials as subscale constituents for a representative volume element of the ply. The micromechanics of the strain rate dependent polymer matrix is represented by an isotropic pressure sensitive viscoelastic-viscoplastic prototype model. For the fibre material, transverse elasticity is assumed. The constituents are homogenized via the fluctuating strain of the subscale, where a simple ansatz is applied to allow for constant stress in the plane transverse to the fibre orientation. Despite the relatively simple modelling assumptions for the constituents, the homogenized model compares favourably to experimental data for an epoxy/carbon fibre based composite, subjected to a variety of challenging uniaxial off-axis tests. The model response clearly reflects observed strain rate dependencies under both tensile and compressive loadings. 

sted, utgiver, år, opplag, sider
Elsevier B.V., 2020
Emneord
Micromechanics, Off-axis loading, Strain rate dependence, Unidirectional (UD) ply, Elasticity, Fiber reinforced plastics, Fibers, Viscoelasticity, Computational homogenization, Fibre-reinforced polymer composites, Representative volume element (RVE), Strain rate dependency, Tensile and compressive loading, Transversely isotropic, Unidirectional composites, Viscoplastic constitutive modeling, Strain rate
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-45150 (URN)10.1016/j.mechmat.2020.103491 (DOI)2-s2.0-85086576741 (Scopus ID)
Merknad

Funding details: Horizon 2020 Framework Programme, H2020; Funding details: H2020 Marie Skłodowska-Curie Actions, MSCA, 721256; Funding details: VINNOVA, 25173-1, 2016-04239; Funding text 1: The authors gratefully acknowledge the support of the ICONIC project under the Marie Skłodowska-Curie grant agreement No 721256 of the European Union Horizon 2020 research and innovation programme. Co-funding has also been provided from the Swedish FFI programme via VINNOVA (dnr 2016-04239) and from the development funds of RISE ( RISE SICOMP SK-project 25173-1).

Tilgjengelig fra: 2020-07-13 Laget: 2020-07-13 Sist oppdatert: 2024-01-17bibliografisk kontrollert
Pallon, L. K. H., Persson, O., Marklund, E., Malm, A. & Johansson, T. (2020). Condition monitoring of excavated CIPP-liners to ensure lifespan. In: 37th International NO-DIG Conference and Exhibition 2019: . Paper presented at 37th International NO-DIG Conference and Exhibition 2019, 30 September 2019 through 2 October 2019. International Society for Trenchless Technology
Åpne denne publikasjonen i ny fane eller vindu >>Condition monitoring of excavated CIPP-liners to ensure lifespan
Vise andre…
2020 (engelsk)Inngår i: 37th International NO-DIG Conference and Exhibition 2019, International Society for Trenchless Technology , 2020Konferansepaper, Publicerat paper (Fagfellevurdert)
Abstract [en]

In Sweden there is a lack of knowledge on the expected service life of installed CIPP-liners and a general aim to request CIPP-liners with a 100-year lifespan. In cooperation with Swedish water utilities a national project has been launched for condition monitoring of used CIPP-liners. A large number of CIPP-liners installed in sewage pipes will be excavated and analyzed in order to evaluate material degradation and estimating remaining service life. The CIPP-liners are all between 5-35 years old. The material performance of the CIPP-liners are either compared with the reference data provided from the installation, or in some case compared to pieces of corresponding CIPP-liners that have been kept in a storage. These pieces becomes especially valuable when looking at possible changes in mechanical properties that may have occurred during the time in use. The materials will be assessed by e.g. bending modulus to investigate material integrity and e.g. FT-IR for chemical stability in the environment of the sewage system. In total the results will give a valuable tool in assessing the expected lifetime of the installed CIPP-liners. The knowledge acquired will help Swedish water utilities to predict service life of installed CIPP-liners and to set sufficient quality demands on new installations for pipe renovation. At an initial stage two excavated CIPP-liners that have been in use for 12 and 16 years have been analyzed and compared with reference data from the time of installation.

sted, utgiver, år, opplag, sider
International Society for Trenchless Technology, 2020
Emneord
Chemical stability, Digital storage, Service life, Sewage, Bending moduli, Expected lifetime, Material degradation, Material integrity, Material performance, National projects, Pipe renovation, Quality demands, Condition monitoring
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-44914 (URN)2-s2.0-85081744780 (Scopus ID)
Konferanse
37th International NO-DIG Conference and Exhibition 2019, 30 September 2019 through 2 October 2019
Merknad

Funding details: VINNOVA; Funding details: Svenskt Vatten, SWWA; Funding details: Sri Venkateswara University, SVU; Funding text 1: This study is financed by InfraSweden 2030 (Vinnova), Development Fund of the Swedish Construction Industry (SBUF) and Swedish Water & Wastewater Association (SVU).

Tilgjengelig fra: 2020-05-20 Laget: 2020-05-20 Sist oppdatert: 2023-05-25bibliografisk kontrollert
Singh, V., Larsson, R., Marklund, E. & Olsson, R. (2019). Effect of strain rate at compressive and tensile loading of unidirectional plies in structural composites. In: Turon A, Maimí P, Fagerström M (Ed.), Proc. 7th ECCOMAS Thematic Conf. on the Mechanical Response of Composites.: . Paper presented at 7th ECCOMAS Thematic Conf. on the Mechanical Response of Composites. (pp. 177-183). European Community on Computational Methods in Applied Science (ECCOMAS)
Åpne denne publikasjonen i ny fane eller vindu >>Effect of strain rate at compressive and tensile loading of unidirectional plies in structural composites
2019 (engelsk)Inngår i: Proc. 7th ECCOMAS Thematic Conf. on the Mechanical Response of Composites. / [ed] Turon A, Maimí P, Fagerström M, European Community on Computational Methods in Applied Science (ECCOMAS) , 2019, s. 177-183Konferansepaper, Publicerat paper (Annet vitenskapelig)
Abstract [en]

Fibre-reinforced polymer composites are widely used in structural applications due to their high specific stiffness and strength. In some applications the response of dynamically loaded composite components must be analysed. For example, in crash analyses of structural components, where very high loading rates occurs, the composite behaviour is not fully understood. For this, we present a novel transversely isotropic viscoelasticviscoplastic constitutive model for a unidirectional carbon-epoxy composite. The model is micromechanically motivated so that the matrix and fibre materials of the composite are treated as micromechanical constituents at the ply scale. Based on the Hill-Mandel condition, the phases are homogenized via the macroscopic and fluctuating strain fields. To arrive at a simple but still representative model, a simplistic ansatz is applied to the structure of the fluctuating strains leading to a non-standard homogenized response of the composite. The model is applied to the non-linear rate dependent anisotropic ply behaviour under quasi-static and dynamic loading at different off-axis angles. For a simple viscoelastic-viscoplastic prototype for the rate dependent matrix response, there is a good correlation between measured and model response of the IM7-8552 material system in compression and tension.

sted, utgiver, år, opplag, sider
European Community on Computational Methods in Applied Science (ECCOMAS), 2019
Emneord
Constitutive model, Strain rate effects, Unidirectional composites
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-42513 (URN)
Konferanse
7th ECCOMAS Thematic Conf. on the Mechanical Response of Composites.
Prosjekter
ICONICFFI-Crash 2
Forskningsfinansiär
EU, Horizon 2020, Grant 721256Vinnova, Dnr 2016-04239
Tilgjengelig fra: 2020-01-09 Laget: 2020-01-09 Sist oppdatert: 2023-06-07bibliografisk kontrollert
Carlstedt, D., Marklund, E. & Asp, L. (2019). Effects of state of charge on elastic properties of 3D structural battery composites. Composites Science And Technology, 169, 26-33
Åpne denne publikasjonen i ny fane eller vindu >>Effects of state of charge on elastic properties of 3D structural battery composites
2019 (engelsk)Inngår i: Composites Science And Technology, ISSN 0266-3538, E-ISSN 1879-1050, Vol. 169, s. 26-33Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

The effects of state of charge (SOC) on the elastic properties of 3D structural battery composites are studied. An analytical model based on micromechanical models is developed to estimate the effective elastic properties of 3D structural battery composite laminae at different SOC. A parametric study is performed to evaluate how different design parameters such as volume fraction of active materials, stiffness of constituents, type of positive electrode material, etc. affect the moduli of the composite lamina for extremes in SOC. Critical parameters and configurations resulting in large variations in elastic properties due to change in SOC are identified. As the extreme cases are of primary interest in structural design, the effective elastic properties are only estimated for the electrochemical states corresponding to discharged (SOC = 0) and fully charged (SOC = 1) battery. The change in SOC is simulated by varying the volume and elastic properties of the constituents based on data from literature. Parametric finite element (FE) models for square and hexagonal fibre packing arrangements are also analysed in the commercial FE software COMSOL and used to validate the analytical model. The present study shows that the transverse elastic properties E2 and G23 and the in-plane shear modulus G12 are strongly affected by the SOC while the longitudinal stiffness E1 is not. Fibre volume fraction and the properties of the coating (such as stiffness and Poisson's ratio) are identified as critical parameters that have significant impact on the effect of SOC on the effective elastic properties of the composite lamina. For configurations with fibre volume fraction Vf ≥ 0.4 and Young's modulus of the coating of 1 GPa or higher, the transverse properties E2 and G23 change more than 30% between extremes in SOC. Furthermore, for configurations with high volume fractions of electrode materials and coating properties approaching those of rubber the predicted change in transverse stiffness E2 is as high as +43%. This shows that it is crucial to take effects of SOC on the elastic properties into account when designing 3D structural battery composite components. © 2018 Elsevier Ltd

Emneord
Carbon fibres, Functional composites, Electrical properties, Elastic properties, C. Modelling, Analytical models, Battery management systems, Charging (batteries), Coatings, Composite structures, Elastic moduli, Elasticity, Electrodes, Fibers, Stiffness, Structural design, Structural properties, Volume fraction, Effective elastic property, Elastic properties, Fibre volume fraction, Functional composites, In-plane shear modulus, Longitudinal stiffness, Parametric finite elements, Positive electrode materials, Secondary batteries
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-36398 (URN)10.1016/j.compscitech.2018.10.033 (DOI)2-s2.0-85056185119 (Scopus ID)
Merknad

 Funding details: Horizon 2020, 738085; Funding details: European Geosciences Union, EGU; Funding details: U.S. Air Force, USAF, FA9550-17-1-0338;

Tilgjengelig fra: 2018-11-22 Laget: 2018-11-22 Sist oppdatert: 2023-05-16bibliografisk kontrollert
Kopp, A., Stappert, S., Mattsson, D., Olofsson, K., Marklund, E., Kurth, G., . . . Roorda, E. (2018). The Aurora space launcher concept. CEAS Space Journal, 10(2), 167-187
Åpne denne publikasjonen i ny fane eller vindu >>The Aurora space launcher concept
Vise andre…
2018 (engelsk)Inngår i: CEAS Space Journal, ISSN 1868-2502, E-ISSN 1868-2510, Vol. 10, nr 2, s. 167-187Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

This paper gives an overview about the Aurora reusable space launcher concept study that was initiated in late-2015/early-2016. Within the Aurora study, several spaceplane-like vehicle configurations with different geometries, propulsion systems and mission profiles will be designed, investigated and evaluated with respect to their technical and economic feasibility. The first part of this paper will discuss the study logic and the current status of the Aurora studies and introduces the first vehicle configurations and their system design status. As the identification of highly efficient structural designs is of particular interest for Aurora, the structural design and analysis approach will be discussed in higher level of detail. A special design feature of the Aurora vehicle configurations is the utilization of the novel thin-ply composite material technology for structural mass reductions. Therefore, the second part of this paper will briefly discuss this technology and investigate the application and potential mass savings on vehicle level within simplified structural analysis studies. The results indicate that significant mass savings could be possible. Finally, an outlook on the next steps is provided.

Emneord
Hypersonics, Launcher, Reusable, Spaceplane, Thin-ply composites, Aerospace vehicles, Computer software reusability, Hypersonic aerodynamics, Launching, Structural design, Design and analysis, Economic feasibilities, Material technologies, Ply composites, Space plane, Vehicle configuration, Hypersonic vehicles
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-33973 (URN)10.1007/s12567-017-0184-2 (DOI)2-s2.0-85047252271 (Scopus ID)
Tilgjengelig fra: 2018-07-03 Laget: 2018-07-03 Sist oppdatert: 2023-05-16bibliografisk kontrollert
Bachinger, A., Marklund, E., André, A., Hellström, P., Rössler, J. & Asp, L. (2015). Materials with variable stiffness. In: ICCM International Conferences on Composite Materials: . Paper presented at 20th International Conference on Composite Materials, ICCM 2015, 19 July 2015 through 24 July 2015. International Committee on Composite Materials
Åpne denne publikasjonen i ny fane eller vindu >>Materials with variable stiffness
Vise andre…
2015 (engelsk)Inngår i: ICCM International Conferences on Composite Materials, International Committee on Composite Materials , 2015Konferansepaper, Publicerat paper (Fagfellevurdert)
Abstract [en]

In this study different concepts to attain a material that can reduce its stiffness upon external stimulation were evaluated regarding their suitability for traffic safety applications. All concepts rely on resistive heating of a carbon fibre reinforcement upon application of electric current through the fibres. The stiffness reduction is achieved by a phase transformation due to heating of the material. The phase transformation takes place either in a thermoplastic interphase, in a thermoplastic matrix or in a thermoset matrix, depending on the concept. The different concepts were studied regarding their thermomechanical and processing properties and their ability to reduce their stiffness upon application of an electric current was tested. Moreover, the materials were evaluated regarding their potential for fast activation, which is crucial for applications in traffic safety. Stiffness-reduction was achieved upon application of an electric current, where the activation temperature was between 60 and 120°C and the extent of stiffness-reduction varied between 50 and 90%, depending on the material. The response time was found to depend to a large extent on the amount of material, which leads to the conclusion that smart design solutions are required for larger parts. It is concluded that the concepts vary in their thermal, mechanical and processing properties as well as in their extent of stiffness-reduction upon activation. The results presented in this work prove the feasibility of the studied materials for traffic safety applications and the concepts allow further optimization of the materials for specific applications

sted, utgiver, år, opplag, sider
International Committee on Composite Materials, 2015
Emneord
Multifunctional composites, Traffic safety, Variable stiffness
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-42227 (URN)2-s2.0-84962755132 (Scopus ID)
Konferanse
20th International Conference on Composite Materials, ICCM 2015, 19 July 2015 through 24 July 2015
Merknad

Funding details: European Commission, 314567; Funding text 1: The authors like to express their gratitude to Runar Långström for manufacturing of composite materials. Moreover, the authors like to express their gratitude to COMFIL for providing material. The presented work was funded by the European Commission within the project ENLIGHT (Grant agreement No: 314567).

Tilgjengelig fra: 2019-12-17 Laget: 2019-12-17 Sist oppdatert: 2023-05-16bibliografisk kontrollert
Organisasjoner
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0003-3755-6419
v. 2.41.0