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Krzak, A., Al-Maqdasi, Z., Nowak, A. J. & Joffe, R. (2024). Effect of Thermomechanical Loading at Low Temperatures on Damage Development in Glass Fiber Epoxy Laminates. Materials, 17(1), Article ID 16.
Open this publication in new window or tab >>Effect of Thermomechanical Loading at Low Temperatures on Damage Development in Glass Fiber Epoxy Laminates
2024 (English)In: Materials, E-ISSN 1996-1944, Vol. 17, no 1, article id 16Article in journal (Refereed) Published
Abstract [en]

Due to the high interest in the use of glass/epoxy laminates in aerospace applications, aviation, and as cryogenic tanks, it is crucial to understand the behavior of composites under challenging environmental conditions. Polymer composites are exposed to low temperatures, including cryogenic temperatures, which can lead to the initiation of microdamage. This paper investigates damage initiation/accumulation and its influence on the properties of cross-ply woven glass fiber epoxy composites at low temperatures compared to room temperature conditions. To evaluate the influence of a low-temperature environment on the mechanical performance of glass fiber reinforced epoxy composite (GFRP) laminates, three types of test campaigns were carried out: quasi-static tensile tests and stepwise increasing loading/unloading cyclic tensile tests at room temperature and in a low-temperature environment (−50 °C). We demonstrated that the initial stiffness of the laminates increased at low temperatures. On the other hand, there were no observed changes in the type or mechanism of developed damage in the two test conditions. However, the reduction in stiffness due to the accumulated damage was more significant for the laminates tested at low temperatures (~17% vs. ~11%). Exceptions were noted in a few formulations where the extent of damage at low temperatures was insignificant (<1%) compared to that at room temperature. Since some of the studied laminates exhibited a relatively minor decrease in stiffness (~2–3%), we can also conclude that the formulation of matrix material plays an important role in delaying the initiation and formation of damage.

Place, publisher, year, edition, pages
Multidisciplinary Digital Publishing Institute (MDPI), 2024
Keywords
epoxy/glass, laminates, low temperature, mechanical test, stiffness degradation
National Category
Composite Science and Engineering
Research subject
Polymeric Composite Materials
Identifiers
urn:nbn:se:ltu:diva-103859 (URN)10.3390/ma17010016 (DOI)2-s2.0-85181973967 (Scopus ID)
Note

Validerad;2024;Nivå 2;2024-01-22 (joosat);

Funder: Polish Ministry of Education and Science (DWD/5/0435/2021);

Full text license: CC BY

Available from: 2024-01-22 Created: 2024-01-22 Last updated: 2024-01-22Bibliographically approved
Bianchi, O., Cruz, J. A., Paim, L., Lavoratti, A., Al-Maqdasi, Z., Amico, S. C., . . . Joffe, R. (2023). Rheology, curing and time-dependent behavior of epoxy/carbon nanoparticles systems. Journal of Applied Polymer Science, Article ID e54821.
Open this publication in new window or tab >>Rheology, curing and time-dependent behavior of epoxy/carbon nanoparticles systems
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2023 (English)In: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, article id e54821Article in journal (Refereed) Epub ahead of print
Place, publisher, year, edition, pages
John Wiley and Sons Inc, 2023
National Category
Composite Science and Engineering
Research subject
Polymeric Composite Materials
Identifiers
urn:nbn:se:ltu:diva-101958 (URN)10.1002/app.54821 (DOI)2-s2.0-85174582769 (Scopus ID)
Note

Funder: Conselho Nacional de Desenvolvimento Científico e Tecnológico (305814/2021-4); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (FinanceCode 001); STINT/CAPES (88881.304743/2018-01)

Available from: 2023-10-31 Created: 2023-10-31 Last updated: 2023-11-30
Al-Maqdasi, Z., Pupure, L., Emami, N. & Joffe, R. (2023). Time-dependent properties of high-density polyethylene with wood/graphene nanoplatelets reinforcement. Polymer Composites, 44(1), 465-479
Open this publication in new window or tab >>Time-dependent properties of high-density polyethylene with wood/graphene nanoplatelets reinforcement
2023 (English)In: Polymer Composites, ISSN 0272-8397, E-ISSN 1548-0569, Vol. 44, no 1, p. 465-479Article in journal (Refereed) Published
Abstract [en]

The effect of graphene nanoplatelets (GNPs) on the long-term performance of wood fiber/high-density polyethylene (HDPE) composite is investigated by using short-term creep tests with an efficient, faster data analysis approach. Previously, it was shown that the addition of GNPs at 15 wt% into HDPE reduces the viscoplastic (VP) strain developed during 2 h creep by ~50%. The current study shows that 25 and 40 wt% wood content in HDPE reduce the VP strains developed during 2 h creep time by >75% with no noticeable effect of the increased wood content. However, further addition of GNPs results in more than 90% total reduction in the VP strains. The current study shows that the development of the VP strains in the hybrid composites follows Zapas model. Viscoelastic (VE) response of these composites is nonlinear and thus is described by Schapery's model. Parameters for VP and VE models are obtained from the creep experiments and were validated in a separate loading-unloading test sequence. Results show a very good agreement between experiments and predictions for the studied materials as long as the micro-damage is not present.

Place, publisher, year, edition, pages
John Wiley & Sons, 2023
Keywords
creep, graphene nanoplatelets, multiscale composites, time-dependent properties, viscoelasticity, viscoplasticity, wood fibers
National Category
Composite Science and Engineering
Research subject
Polymeric Composite Materials; Machine Elements
Identifiers
urn:nbn:se:ltu:diva-90137 (URN)10.1002/pc.27110 (DOI)000877029700001 ()2-s2.0-85141407844 (Scopus ID)
Funder
European Regional Development Fund (ERDF), 1.1.1.2/VIAA/4/20/646EU, Horizon 2020, 777810 Nano2Day
Note

Validerad;2023;Nivå 2;2023-04-19 (hanlid);

Available from: 2022-04-08 Created: 2022-04-08 Last updated: 2023-04-19Bibliographically approved
Al-Maqdasi, Z., Pupure, L., Emami, N. & Joffe, R. (2022). Analysis of long-term performance of wood polymer composites with added multifunctionality. In: 80th International Scientific Conference of the University of Latvia - Advanced Composites and Applications: Book of Abstracts. Paper presented at 80th International Scientific Conference of the University of Latvia, February 15, 2022, Riga, Latvia (pp. 9). Riga: University of Latvia
Open this publication in new window or tab >>Analysis of long-term performance of wood polymer composites with added multifunctionality
2022 (English)In: 80th International Scientific Conference of the University of Latvia - Advanced Composites and Applications: Book of Abstracts, Riga: University of Latvia , 2022, p. 9-Conference paper, Oral presentation with published abstract (Other academic)
Place, publisher, year, edition, pages
Riga: University of Latvia, 2022
National Category
Composite Science and Engineering Polymer Technologies
Research subject
Polymeric Composite Materials; Machine Elements
Identifiers
urn:nbn:se:ltu:diva-96169 (URN)
Conference
80th International Scientific Conference of the University of Latvia, February 15, 2022, Riga, Latvia
Note

Funder: NANO2Day (777810)

Available from: 2023-03-16 Created: 2023-03-16 Last updated: 2024-01-08Bibliographically approved
Pupure, L., Varna, J., Gailitis, R., Al-Maqdasi, Z. & Pakrastins, L. (2022). Development of methodology for experimental parameter identification for inelastic 3D material model. In: Vassilopoulos, Anastasios; Michaud, Véronique, Lausanne (Ed.), ECCM 2022 - Proceedings of the 20th European Conference on Composite Materials: Composites Meet Sustainability. Paper presented at 20th European Conference on Composite Materials (ECCM20), June 26-30, 2022, Lausanne, Switzerland (pp. 282-289). Lausanne: EPFL Lausanne, Composite Construction Laboratory, 6
Open this publication in new window or tab >>Development of methodology for experimental parameter identification for inelastic 3D material model
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2022 (English)In: ECCM 2022 - Proceedings of the 20th European Conference on Composite Materials: Composites Meet Sustainability / [ed] Vassilopoulos, Anastasios; Michaud, Véronique, Lausanne, Lausanne: EPFL Lausanne, Composite Construction Laboratory , 2022, Vol. 6, p. 282-289Conference paper, Published paper (Other academic)
Abstract [en]

Lately due to advancement of materials, structures and modeling capacities demand for 3D nonlinear material models implemented in commercial software’s and codes have increased. In order to obtain such implemented model, firstly the model itself and the methodology for experimental parameter identification have to be established. The overall goal is to create a 3D material model, that could account for viscolpasticity, viscoelasticity and damage. Within this study the viscoplastic behavior in axial and lateral direction will be analyzed, thus obtaining the materials 3D viscoplastic behavior. Experimental data for various materials are analyzed. The results showed that viscoplastic strain has the same time and stress dependency in axial and lateral direction. The only difference is in the ration of axial and lateral strain, which is characterized by a single multiplication factor within viscoplastic material model. 

Place, publisher, year, edition, pages
Lausanne: EPFL Lausanne, Composite Construction Laboratory, 2022
Keywords
Nonlinearity, 3D, viscoplasticity, strain recovery, creep
National Category
Composite Science and Engineering
Research subject
Polymeric Composite Materials
Identifiers
urn:nbn:se:ltu:diva-96168 (URN)10.5075/epfl-298799_978-2-9701614-0-0 (DOI)2-s2.0-85149412735 (Scopus ID)978-2-9701614-0-0 (ISBN)
Conference
20th European Conference on Composite Materials (ECCM20), June 26-30, 2022, Lausanne, Switzerland
Funder
European Regional Development Fund (ERDF)
Available from: 2023-03-16 Created: 2023-03-16 Last updated: 2023-05-15Bibliographically approved
Nunes, S. G., Al-Maqdasi, Z., Fernberg, P., Amico, S. C. & Varna, J. (2022). Does the viscoelastic behavior of fully cured epoxy depend on the thermal history during curing?. Journal of composite materials, 56(22), 3439-3453
Open this publication in new window or tab >>Does the viscoelastic behavior of fully cured epoxy depend on the thermal history during curing?
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2022 (English)In: Journal of composite materials, ISSN 0021-9983, E-ISSN 1530-793X, Vol. 56, no 22, p. 3439-3453Article in journal (Refereed) Published
Abstract [en]

Residual strains and shape distortions in a polymer-based composite structure may depend on the cure schedule used for manufacture. Aiming to understand the cure history effects, the influence of the curing “path” (time tc and temperature Tc path during curing) on viscoelastic (VE) response of a fully cured (FC) (alpha = 0.992) epoxy was investigated. Five different “families” of the same epoxy were manufactured in constraint-free conditions using different sets of curing parameters. Then, tensile tests were performed at different temperatures (T = 30 to 110 °C), and the time-temperature superposition principle (TTSP) and Schapery’s type of linear viscoelastic (VE) model, accounting for physical aging of specimens tested at high temperature, were used. The results show that the VE properties of the studied epoxy are independent of the curing history provided that at the end all specimens are fully cured. Also, the physical aging rate at high temperatures of all “families” is the same and it can be described by a simple aging-temperature independent equation reported in Nunes et al1 It is expected that curing history of unconstrained and fully cured epoxy has an insignificant effect on final viscoelastic behavior, a knowledge which could assist in developing more time and cost-efficient cure cycles.

Place, publisher, year, edition, pages
Sage Publications, 2022
Keywords
epoxy, curing history, viscoelasticity, physical aging, shift factors, simulations
National Category
Other Materials Engineering
Research subject
Polymeric Composite Materials; Machine Elements
Identifiers
urn:nbn:se:ltu:diva-92323 (URN)10.1177/00219983221115850 (DOI)000826103600001 ()2-s2.0-85134535047 (Scopus ID)
Note

Validerad;2022;Nivå 2;2022-09-26 (hanlid);

Funder: European Regional Development Fund (1.1.1.2/VIAA/4/20/641); Swedish Foundation for International Cooperation in Research and Higher Education, STINT; Higher Education Improvement Coordination CAPES/Brazil

Available from: 2022-07-29 Created: 2022-07-29 Last updated: 2022-09-26Bibliographically approved
Viesturs, L., Alens, Š., Andrejs, P. & Al-Maqdasi, Z. (2022). Experimental and numerical analysis of heat dissipation in hybrid carbon/glass thin-ply composites for multifunctional applications. In: Vassilopoulos, Anastasios; Michaud, Véronique (Ed.), ECCM 2022 - Proceedings of the 20th European Conference on Composite Materials: Composites Meet Sustainability. Paper presented at 20th European Conference on Composite Materials (ECCM20), June 26-30, 2022, Lausanne, Switzerland (pp. 122-128). Lausanne: EPFL Lausanne, Composite Construction Laboratory, 3
Open this publication in new window or tab >>Experimental and numerical analysis of heat dissipation in hybrid carbon/glass thin-ply composites for multifunctional applications
2022 (English)In: ECCM 2022 - Proceedings of the 20th European Conference on Composite Materials: Composites Meet Sustainability / [ed] Vassilopoulos, Anastasios; Michaud, Véronique, Lausanne: EPFL Lausanne, Composite Construction Laboratory , 2022, Vol. 3, p. 122-128Conference paper, Published paper (Other academic)
Abstract [en]

Thermal behavior of hybrid carbon/glass thin-ply laminates with different layer thickness ratios were investigated experimentally. Two different approaches were used for applying thermal loads: in one experiment small-scale external heater was attached on the surface of laminate specimen; in the second approach cyclic mechanical loading with high frequency was applied to generate internal heating within materials. In both experiments transient temperature distribution along the thickness of specimens was measured and recorded using high performance thermal imaging camera. Obtained results demonstrate temperature distribution in reference and hybrid laminate layers during the transient and steady state thermal conditions. Relatively large differences between carbon/epoxy and glass/epoxy layers were found in terms of internal heat generation and heat transfer. Parametric analysis results on reference and various hybrid lay-ups from this study could aid the lay-up design for composites in multifunctional applications with various thermal processes.

Place, publisher, year, edition, pages
Lausanne: EPFL Lausanne, Composite Construction Laboratory, 2022
Keywords
heat dissipation, thermal imaging, thin-ply laminates
National Category
Composite Science and Engineering Energy Engineering
Research subject
Polymeric Composite Materials
Identifiers
urn:nbn:se:ltu:diva-95874 (URN)10.5075/epfl-298799_978-2-9701614-0-0 (DOI)2-s2.0-85149172804 (Scopus ID)978-2-9701614-0-0 (ISBN)
Conference
20th European Conference on Composite Materials (ECCM20), June 26-30, 2022, Lausanne, Switzerland
Funder
European Regional Development Fund (ERDF)
Available from: 2023-03-14 Created: 2023-03-14 Last updated: 2023-03-14Bibliographically approved
Al-Maqdasi, Z. (2022). Multifunctionality and Durability of Cellulosic Fiber Reinforced Polymer Composites. (Doctoral dissertation). Luleå University of Technology
Open this publication in new window or tab >>Multifunctionality and Durability of Cellulosic Fiber Reinforced Polymer Composites
2022 (English)Doctoral thesis, comprehensive summary (Other academic)
Alternative title[sv]
Multifunktionalitet och beständighet hos cellulosabaserade fiberkompositer
Abstract [en]

The overall objective of this thesis is to develop and evaluate cellulose-based fiber composites with added multifunctionality for advanced applications. In the strive towards sustainable societies and industries, materials as well as production processes need to be assessed against the sustainability criteria and selected accordingly. Cellulosic fibers reinforced polymer composites are being increasingly used in applications where weight saving, and environmental friendliness is as important as structural performance. Nonetheless, these materials have their limitations regarding durability and stability of the properties, but their potential in use for advanced applications can be expanded if functionalized and considered beyond their structural performance. Such multi-functionality of composites can be achieved by the coating of fibers and/or modifying the matrix with functional reinforcement, or by both of these routes combined. Coating of fibers and modifying the matrix with nano-reinforcement are two selected approaches for imparting functionality to the cellulosic fiber composites in the current study. 

Conductive Regenerated Cellulose Fibers (RCFs) were produced by coating commercial RCFs with copper via electroless plating process. Electrical conductivity and mechanical performance were evaluated, and the coated fibers were transformed into an embedded strains sensor-like assembly that could be used as structural health monitoring system in composites structures. A noticeable degradation in the mechanical strength of fibers was realized and it was attributed to the influence of the chemicals of the final plating step of process on the chains of cellulose as well as the loss of crystalline order in the RCF. 

In order to obtain modified matrix (nanocomposites) for multifunctional wood polymer composites (WPC), the commercial masterbatches based on Graphene Nanoplatelets (GNPs) were utilized by melt extrusion process. Effect of the processing parameters in terms of change in screw configurations and the change in composition of the constituents on the structure and mechanical performance of the nanocomposites was studied.  Results showed that there is insignificant effect of the change in the screw configuration in comparison with the effect of increasing the content of the GNPs. Stronger shear forces did not result in better dispersion of the nanoparticles. Addition of the compatibilizer, on the other hand, resulted in an adverse effect on the properties compared to the formulations where it is absent. The use of GNPs with larger aspect ratio resulted in much better improvement in the mechanical performance. Addition of the nanoparticles did not only improve mechanical performance but also resulted in increased thermal conductivity and diffusivity, especially when micro-scale reinforcement was added because of synergy between wood fibers and the GNPs. This synergy was reflected also in the significant 99% improved wear resistance and the >80% reduction in the creep strains of wood and graphene reinforced composites. 

During the design and selection of materials, quasi-static properties are often used as a selection criterion. However, in reality structures in use are often loaded during lengthy periods of time which are followed by multiple steps of unloading/reloading, depending on the service conditions.  In such cases their time-dependent response becomes more crucial than instantaneous mechanical response. Typically, characterization of these properties requires a lot of time, but it may be significantly shortened if proper modeling and analysis are employed. The effect of addition of GNPs to the polymer and wood composites has been studied experimentally by short term creep tests. The materials showed highly nonlinear response even at very low loading stresses, but the addition of the nanoparticles resulted in a decrease in the nonlinearity and in the irreversible strains due to plasticity. Modelling approaches have been used to extract parameters from experimental data that could be used in predicting long term performance using Zapas model for viscoplasticity and Schapery’s model for nonlinear viscoelasticity. 

Overall, the results of the performed work contribute to enriching the research field with the potential the bio-based composites have to offer in the advanced application and how nano-scale reinforcement can interact synergistically with the micro-sized fibers to improve the overall performance of WPC and under different loading scenarios.  

Place, publisher, year, edition, pages
Luleå University of Technology, 2022
Series
Doctoral thesis / Luleå University of Technology 1 jan 1997 → …, ISSN 1402-1544
National Category
Composite Science and Engineering
Research subject
Polymeric Composite Materials
Identifiers
urn:nbn:se:ltu:diva-90138 (URN)978-91-8048-057-4 (ISBN)978-91-8048-058-1 (ISBN)
Public defence
2022-06-09, E632, Universitetsområdet Porsön, Luleå, 12:30 (English)
Opponent
Supervisors
Available from: 2022-04-08 Created: 2022-04-08 Last updated: 2022-05-19Bibliographically approved
Al-Maqdasi, Z., Sott, R., Mattsson, C., André, A. & Joffe, R. (2022). Performance of recycled glass fibers from composite parts by different treatments. In: Vassilopoulos, Anastasios; Michaud, Véronique (Ed.), ECCM 2022 - Proceedings of the 20th European Conference on Composite Materials: Composites Meet Sustainability. Paper presented at 20th European Conference on Composite Materials (ECCM20), Lausanne, Switzerland, June 26-30, 2022 (pp. 77-84). Lausanne: EPFL Lausanne, Composite Construction Laboratory, 6
Open this publication in new window or tab >>Performance of recycled glass fibers from composite parts by different treatments
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2022 (English)In: ECCM 2022 - Proceedings of the 20th European Conference on Composite Materials: Composites Meet Sustainability / [ed] Vassilopoulos, Anastasios; Michaud, Véronique, Lausanne: EPFL Lausanne, Composite Construction Laboratory , 2022, Vol. 6, p. 77-84Conference paper, Published paper (Other academic)
Abstract [en]

In this work, glass fibers have been retrieved from decommissioned composite parts by three different methods. Namely, (i) pyrolysis, (ii) a novel solvolysis and (iii) a combination of solvolysis followed by pyrolysis. The techniques allowed successful recovering of sufficiently long fiber bundles (> 30 mm) that enabled separating single fibers for manual handling and testing. Single fiber tensile tests were performed to evaluate the efficiency of different recovery methods to preserve properties in comparison to the virgin fibers. The mechanical test results revealed that the stiffness of the recovered fibers has not been affected by the treatments. On the other hand, around 45% of the fiber’s strength was retained after the solvolysis process which is a comparable value to that found in literature. 

Place, publisher, year, edition, pages
Lausanne: EPFL Lausanne, Composite Construction Laboratory, 2022
Keywords
Glass fiber, recovery, solvolysis, pyrolysis, mechanical properties
National Category
Composite Science and Engineering
Research subject
Polymeric Composite Materials
Identifiers
urn:nbn:se:ltu:diva-96167 (URN)10.5075/epfl-298799_978-2-9701614-0-0 (DOI)2-s2.0-85149360317 (Scopus ID)978-2-9701614-0-0 (ISBN)
Conference
20th European Conference on Composite Materials (ECCM20), Lausanne, Switzerland, June 26-30, 2022
Funder
Vinnova, 2018-04132
Available from: 2023-03-16 Created: 2023-03-16 Last updated: 2023-05-15Bibliographically approved
Al-Maqdasi, Z., Joffe, R. & Emami, N. (2022). Synergistic Effect of Multiscale Reinforcement on Wear of Wood Polymer Composites. In: PolyTrib 2022: . Paper presented at 4th International Conference on Polymer Tribology, December 5-6 2022, Stockholm, Sweden (pp. 34-35).
Open this publication in new window or tab >>Synergistic Effect of Multiscale Reinforcement on Wear of Wood Polymer Composites
2022 (English)In: PolyTrib 2022, 2022, p. 34-35Conference paper, Oral presentation with published abstract (Other academic)
Keywords
nanocomposites, Tribology, parameters, mechanical performance
National Category
Composite Science and Engineering Tribology (Interacting Surfaces including Friction, Lubrication and Wear)
Research subject
Polymeric Composite Materials; Machine Elements
Identifiers
urn:nbn:se:ltu:diva-96170 (URN)
Conference
4th International Conference on Polymer Tribology, December 5-6 2022, Stockholm, Sweden
Available from: 2023-03-16 Created: 2023-03-16 Last updated: 2024-01-12Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-5550-2962

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