Etude du comportement dynamique couplé au vieillissement des composites totalement recyclés à renfort carbone : de la caractérisation à la modélisation

Abstract : In the automotive sector, integrating more and more recycled composite materials while improving the initial performance and decreasing the carried masses becomes a compromise that needs to be addressed. Moreover, structural parts made of composite materials intended for crash are often subjected to environmental conditions, including moderately high temperatures, capable of causing gradual physico-chemical degradation. Thus, to ensure better design and durability of parts, it is important to understand the influence of thermal aging on the dynamic properties of materials. To this end, this work aims to couple the physics of oxidative degradation kinetics and the multi-scales mechanical behavior of a new fully recycled composite based on a polypropylene matrix and carbon fibers. The first axis of the study is dedicated to the elaboration, the physicochemical, microstructural and mechanical characterization of several formulations of composites. Once the optimal composite is selected, a hybrid experimental and numerical methodology is s is developed in order to characterize the dynamic properties at high strain rates reaching 100 s-1. The second axis of this work is focused on the study of the influence of thermo-oxidation on the physicochemical and mechanical properties at different strain rates of the optimal composite and its matrix. The resulting experimental has allowed the identification of a kinetic model parameters based on a mechanistic scheme. Furthermore, a qualitative and quantitative study of the effect of aging on the damage mechanisms has been carried out at a microscopic scale in order to establish a damage law linking, for a given imposed strain, the local damage density to the concentration of the oxidation products. The results of this study highlight the possibility of developing behavioral laws affected by the parameters of kinetic models describing the evolution of the physicochemical state of the composite during aging.
Complete list of metadatas

https://pastel.archives-ouvertes.fr/tel-01768436
Contributor : Abes Star <>
Submitted on : Tuesday, April 17, 2018 - 11:39:06 AM
Last modification on : Wednesday, June 12, 2019 - 5:02:57 PM

File

MEFTAH.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01768436, version 1

Collections

Citation

Hassen Meftah. Etude du comportement dynamique couplé au vieillissement des composites totalement recyclés à renfort carbone : de la caractérisation à la modélisation. Mécanique des matériaux [physics.class-ph]. Ecole nationale supérieure d'arts et métiers - ENSAM; Ecole Nationale d'Ingénieurs de Sousse-ENISo (Tunisie), 2018. Français. ⟨NNT : 2018ENAM0014⟩. ⟨tel-01768436⟩

Share

Metrics

Record views

1430

Files downloads

232