Wyniki wyszukiwania - Biblioteka Nauki

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Study of the Effect of Heat Stress on the Damage of the Fibre Matrix Interface of a Composite Material (T300/914) by Means of a Genetic Algorithm

100%

Mokaddem A. , Allami M. , Temimi L. , Boutaous A.

Fibres & Textiles in Eastern Europe

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2012

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tom Vol. 20, no. 6A (95)

108--111

EN

The aim of this paper is to develop an analytical model to evaluate the influence of thermal stress on damage to the fiber-matrix interface of a composite T300/914 from the properties of the fibre, as well as from the matrix and characteristics of the interfacial binding. The model developed by a genetic algorithm takes into account the temperature effects that result in the progressive degradation of the fibre-matrix. This work shows the influence of thermal stress beyond the critical threshold of damage to the interface, and that the matrix damage has an important influence on the damage to the interface compared to that of the fiber.

PL

Celem badań było opracowanie modelu analitycznego do oceny wpływu stresu termicznego na uszkodzenia warstwy międzyfazowej kompozytu T300/914 na podstawie właściwości włókien i matrycy oraz charakterystyki połączenia. Model opracowany przez algorytm genetyczny uwzględnia wpływ temperatury, który prowadzi do degradacji matrycy. Artykuł opisuje również wpływ stresu termicznego w warunkach krytycznych.

2

Investigation and simulation by a metaheuristic algorithm of the effect of carbon nanotubes fibers on the improvement of the properties of nanocomposite material

75%

Oukkas M. , Mokaddem A. , Doumi B. , Boutaleb M. , Temimi L. , Boutaous A.

Mechanics and Mechanical Engineering

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2017

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tom Vol. 21, nr 4

1009--1020

EN

In this article, we investigated and studied the effect of carbon Nanotubes fibers on the improvement of the mechanical and thermal properties of our epoxy matrix composite material. Our calculations were based on a heuristic optimization algorithm. The results show that the level of the damage is related to the concentration of the mechanical and thermal stresses, for the three materials studied carbon/epoxy, Graphite-epoxy and carbon nanotubes/epoxy, the calculations also show that carbon nanotubes have greatly improved the mechanical and physical properties of our material, and that this material is more resistant than the other carbon/epoxy composite materials and graphite-epoxy nanocomposite. The numerical simulation shows a good agreement with the real behavior of the three materials studied. This means that the mechanical and physical properties have been greatly improved after the use of carbon nanotubes fibers. Finally, we can say that our model has worked well in relation to the phenomenon of damage of composites and nanocomposites materials. It would be interesting to see, thereafter, the effect of carbon nanotubes fibers on the damage of the fiber-matrix interface of a bio-nanocomposite.

3

Comparative Studies by a Genetic Algorithm on the Mechanical Properties of PLA and Expoxy Biocomposite Materials Reinforced with Alfa Natural Fiber

75%

Tadjedit S. , Temimi L. , Boutaous A. , Mokadem A. , Doumi B. , Beldjoudi N.

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2016

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tom Vol. 20, nr 3

331--345

EN

The natural bers are indeed a renewable resource, biodegradable and naturally with technical qualities and very high mechanical properties. The mechanical properties of reinforcement biocomposites as alfa / polylactic acid (PLA) are largely conditioned by the interfacial bond between the two materials (ber and matrix). To characterize this link and locate damage to the ber-matrix interface, we used a genetic approach based on the Cox model and formalism of Weibull. This model taking into account the micromechanical behavior of the three composite and biocomposites materials: Glass/epoxy, alfa / epoxy and alfa / PLA. The results of this simulation show that the damage level of the interface is related to the nature of the materials used and the applied mechanical stress, and has shown that the green material alfa / PLA is stronger than the biomaterial alfa / epoxy. The results of this modeling are in agreement with those obtained experimentally by Antoine et al. So the natural bers have a very important role in enhancing the mechanical strength of composite and biocomposites materials.

4

Study and localization by the nonlinear acoustic technique of the damage to the fiber-matrix interface of a bio-composite

75%

Attemane A. , Mokaddem A. , Doumi B. , Boutaleb M. , Temimi L. , Boutaous A.

Mechanics and Mechanical Engineering

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2017

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tom Vol. 21, nr 3

453--465

EN

The objective of this paper is to study the effect of dissipated energy on the damage to the fiber-matrix interface of a Hemp/Pla bio-composite, localized by the non-linear acoustic technique. For this purpose, we used the model defining energy dissipation during a charge/discharge cycle in our numerical simulation based on the Weibull probabilistic model and Cox model. We found that the energy dissipated is directly related to the damage; and when the damage increases the dissipated energy increases rapidly in the first cycles (1, 2,3 and 4) and very quickly for the last charge/discharge cycles (5,6 and 7). We concluded that the energy dissipated showed the state of degradation of Biocomposite prior to its start-up, and that the non-linear acoustic technique also indicates and confirms the same results found.