Mylène Deléglise Lagardère

• PhD in Material Sciences
• Professor (Assistant) at IMT Nord Europe

This study evaluates multimodal imaging for characterizing microstructures in partially impregnated thermoplastic matrix composites made of woven glass fiber and polypropylene. The research quantifies the impregnation degree of fiber bundles within composite plates manufactured through a simplified compression resin transfer molding process. For co...

This experimental study evaluates multi-modal imaging techniques for characterizing microstructures in partially impregnated thermoplastic matrix composites made from woven glass fibre (WGF) and polypropylene (PP). The research focuses on the impregnation quality of composite plates manufactured through a displacement-controlled thermo-compression...

This experimental study investigates impregnation mechanisms and porosity localization in thermoplastic composite plates using a displacement-controlled thermo-compression technique, representing the impregnation phase as a variant of a CRTM process with through-thickness matrix flow [1]. Plates were manufactured using varied compaction ratios (Cr)...

The current work, suggests combination of different imagery techniques to observe the same structure for higher fidelity porosity quantification

This work sheds light on the first steps towards using glass fiber waste for semi-structural applications. This work aims to improve the properties of random flax fiber composites by incorporating waste glass fibers (WGF) obtained from the fiber production line. The waste glass fibers were incorporated as a core structure between the flax layers to...

A new type of flax fiber-reinforced bio-sourced thermoset composites is investigated to explore their usage in hot and humid conditions and is compared with flax fiber reinforced epoxy composites. Hygrothermal aging of composites is carried out for 40 days at 50 °C and 90%RH. The influence of moisture uptake of composites during aging is evaluated...

In this work, manufacturing tools for thermoplastic (TP) composites have been developed. The chosen process involves the stacking alternately of oriented dry fabrics and TP films and does not use semi-products in order to reduce material costs. This study was specifically directed towards optimizing the impregnation of continuous glass and carbon f...

Absorption-based microcomputed tomography (µCT) scans using polychromatic X-ray sources are frequently used to analyse the microstructure of polymer-matrix composites. Assuming the proportionality between linear X-ray attenuation coefficients and gray levels in the reconstructed µCT images, segmentation techniques can be used to conduct qualitative...

This study sheds light on the effect of resin cure cycle on the tensile properties of unidirectional flax fibers, which are assessed by the impregnated fiber bundle test (IFBT). The experimental protocol combines hand-layup and isothermal compression molding processes to fabricate unidirectional flax composites according to four different curing cy...

We propose an efficient simulation method of three-dimensional (3D) resin flow in laminated preform composed of multiple layers with different permeabilities at each layer. Because of the small thickness of each layer, a huge number of nodes are needed for 3D flow simulation if solid elements are adopted and full 3D simulation takes extremely long...

Laser Transmission Welding process (LTW) is a well know technic for polymer welding. This technic can also be applied to thermoplastic glass fiber composite (polymer + continuous glass fibers). But in this case two phenomenon occur and are able to make the welding in a poor quality: light absorption and light scattering. The two phenomenon occurrin...

An efficient experimental method is proposed to measure very low permeability of composite laminated preform fabricated by automated dry fiber tape placement. A new computer program is also presented for the numerical simulation of three dimensional resin flow which is generally impossible by conventional commercial packages due to an extremely hea...

We propose a new experimental method using a Hassler cell and air injection to measure the permeability of fiber preform while avoiding a race tracking effect. This method was proven to be particularly efficient to measure very low through-thickness permeability of preform fabricated by automated dry fiber placement. To validate the reliability of...

The construction of mesoscopic models of fiber washing effects during the high pressure resin transfer molding (RTM) process with thermoplastic polymers requires the knowledge of the limit of adhesion coefficients between dry and impregnated fabric reinforcement plies and the mold. To measure these coefficients, a new method is described. During RT...

A new analytical formulation of governing equations for hydro-mechanical coupled problem during single sided molding processes such as vacuum infusion (VI) is presented in this study. The main complexities of VI modeling are the non-linear pressure profile and thickness evolution during filling. The research is focused on the relationship between f...

Thermoplastic composites have an increasing demand in the automotive industry. However, their relatively high viscosity poses manufacturing challenges. Especially in the RTM process lower viscosities or process changes are required to overcome bundle deformation or preform washing. To improve the cycle time and the part quality CETIM is developing...

We investigate the influence of liquid type on the saturated permeability of natural fabrics in liquid composite molding processes. The permeability of flax woven fabric was characterized with two different liquids which have different viscosity, wettability, and sorption characteristics with flax fiber. From the experimental data, it was observed...

Recently, natural fibers are attracting great interest from automotive industry by virtue of their environmental friendliness as well as high specific stiffness. Liquid composite molding (LCM) processes have a high potential as a manufacturing process of natural fiber reinforced composite structures by dint of high fiber volume fraction to enhan...