Patricia Krawczak

Ecole Nationale Supérieure Mines-Télécom Lille Douai (IMT Nord Europe), Institut Mines-Télécom (IMT)

Structural composite manufacturing in automotive industry tends towards short cycle times for being competitive with other material solutions. Development towards resin transfer molding process can be considered when highly reactive resin with short curing cycle is used. Mixing of the resin system components is then held at the mold inlet to reduce...

Polymer composite materials are being increasingly used in primary load-bearing structures in several advanced industrial fields such as aerospace vessels, railway wagons and mega-scaled wind turbines where detection of subcritical damage initiation can significantly reduce safety issues and maintenance costs. It is therefore crucial to inspect the...

The demand for thermoplastic composites is continuously increasing because these materials offer many advantages over their thermoset counterparts, such as high toughness, long storage time, easy repairing and recycling, and ability to be thermoformed and heat-welded. However, the manufacturing of thermoplastic composite parts using liquid composit...

Non-destructive testing (NDT) techniques are usually used for the characterisation of defects arising in polymer composites during manufacturing or in-service use. However, each of these NDT techniques cannot always allow a full diagnosis of the material’s or component’s structural health. Thus, several techniques have to be combined in order to im...

Environmental and energy concerns and digitalization are currently profoundly reshaping the plastics and composites industry. Manufacturing processes and systems evolve accordingly in order to cost-effectively produce high-performance, high-quality, lightweight, and multifunctional parts with a reduced carbon footprint. All composites manufacturing...

Non-destructive testing techniques (NDT) are usually used for characterization of defects arising in composite materials during manufacturing or during in-service use. NDT techniques such as ultrasonic waves, X-ray radiography, X-ray tomography, infrared thermography, acoustic emission are the most commonly used in various industrial applications....

Environmental imperatives are increasingly steering industrial focus toward sustainable materials, positioning fiber-reinforced thermoplastic (FRT) composites as pivotal solutions. These composites confront significant developmental and optimization challenges for structural applications, primarily due to their complex multi-scale reinforcement str...

This Special Issue explores significant research on fiber-reinforced thermoplastic composites, including advancements in material development, process optimization, sustainability, and multimodal characterization techniques. Featured topics include low-density, high-performance composite foams, flame-retardant panels, and eco-friendly bio-composite...

The 3rd volume of the "Women in Science : Materials" collection in "Frontiers in Materials" showcases the standout research of female researchers across the breadth of the materials science and engineering. It gathers a selection of articles with the lead author and/or corresponding author being a woman. Manuscripts span several sections of the jou...

SFIP – the French Society of Plastics Engineers – and IMT Nord Europe – an engineering graduate school of the Institut Mines-Télécom – are launching the second edition of the Plastics Industry & Environment congress to be held in Douai (France) on 22 & 23 May, 2024. The current concerns related to sustainability and environmental footprint drive i...

Polymeric and composite materials are ubiquitous today. However, to improve their sustainability, it is of paramount importance to make sure that their waste does not end up in landfill or in the environment, and to to find ways to recover and reuse these materials in useful and profitable applications. To contribute to building a resource-efficien...

The recovery and recycling/upcycling of plastics and polymer-based materials is needed in order to reduce plastic waste accumulated over decades. Mechanical recycling processes have made a great contribution to the circularity of plastic materials, contributing to 99% of recycled thermoplastics. Challenges facing this family of processes limit its...

The search for eco-responsible solutions is attracting the interest of end-use industries toward fiber-reinforced thermoplastic composites (FRT). However, numerous challenges are still limiting the development of efficient optimization approaches of FRT composites for structural parts. Such challenges emanate from complexities related to (i) the mu...

This Special Issue reprint focuses on the latest advances and development of fusion bonding/welding of polymer composites. It contains research articles addressing materials, processing, modeling, monitoring, or performance issues with experimental or numerical approaches. Whatever the process, e.g., resistance, induction, ultrasonic, laser or cond...

Most of everyday products and industrial structures are made by the assembly of several parts and therefore contain joints. This is the case for example in the aeronautics, railway or automotive industry where polymer composites become more and more popular as lightweight substitutes of metallic materials. Joining of polymer composites may be achie...

The present study investigated the influence of temperature on molecular interdiffusion at the interface during the laser transmission welding of 3D-printed continuous carbon-fiber-reinforced thermoplastic composites. In order to accurately measure the temperature at the weld interface, a series of thermocouples were embedded in the laser-absorbent...

This article highlights how composite laminates embedding functionalised glass fibre fabrics (ply with tracks made of the patented EOPROM® copper-based formulation) can be endowed with electronic functions without compromising their mechanical behaviour.

According to UNESCO Institute for Statistics data (UIS, 2020), female scientists account for a minority of the world’s researchers. Only 30% of researchers worldwide are women. Long-standing biases and gender stereotypes are discouraging girls and women away from science-related fields. In particular, STEM (science, technology, engineering, and mat...

The 2nd volume of the "Women in Science : Materials" collection in "Frontiers in Materials" showcases the standout research of female researchers across the breadth of the materials science and engineering. It gathers a selection of 7 articles with the lead author and/or corresponding author being a woman. Manuscripts span several sections of the j...

The ‘ReShaping Plastics’ (https://www.systemiq.earth/reshaping-plastics/) report issued in April 2022 aims at helping leaders and decision-makers to find effective pathways to a highly circular, climate-neutral plastics system in Europe, focusing on the most important plastic-using sectors (packaging, household goods, automotive, and construction)....

SFIP – the French Society of Plastics Engineers - and IMT Nord Europe – an engineering graduate school of the Institut Mines-Télécom – launch a new congress entirely dedicated to polymeric materials and environment *** A plastics industry’s key event : Organised on 18 and 19 May 2022 on the Douai campus of IMT Nord Europe (France) with the support...

The Frontiers in Materials Editorial Office team are delighted to present the inaugural “Women in Science: Materials” article collection, showcasing the high-quality work of women in science across the breadth of materials science and engineering. All researchers featured within this collection were individually nominated by the Topic Editors in re...

According to UNESCO Institute for Statistics (UIS) data (UIS fact sheet, 2019), less than 30% of researchers worldwide are women. Long-standing biases and gender stereotypes are discouraging girls and women away from science related fields. In particular, STEM (science, technology, engineering and mathematics) research is traditionally male dominat...

Polymers have become one of the key materials to manufacture high-performing, lightweight, fuel-efficient , safe, and affordable cars. Accounting for roughly one third of the parts in a vehicle, plastics meet traditional automotive requirements rather well: high specific mechanical properties, impact, thermal and chemical resistance, customization...

The inaugural "Women in Science : Materials" collection in "Frontiers in Materials" showcases the standout research of female researchers across the breadth of the materials science and engineering. It gathers a selection of 32 articles with the lead author and/or corresponding author being a woman. Manuscripts span all sections of the journal, the...

An inverse method for determining the in-plane effective thermal conductivity of porous thermoplastics was implemented by coupling infrared thermography experiments and numerical simulation of heat transfer in straight fins having temperature-dependent convective heat transfer coefficient. The microstructure heterogeneity of extruded polyethylene f...

The growing concerns about the environment and energy have driven the widespread adoption of new lightweight materials such as polymer composites in many industrial sectors, crucial issues being performance, cost efficiency, and multifunctionality (Krawczak, 2019). Among them, thermosetting matrix composites offer not only many advantages such as h...

Les matériaux aussi ont des problèmes de santé. Même les plus résistants comme les composites ne sont pas épargnés ! A leur naissance, lors de leur élaboration, ou plus tard au cours de leur vie en service, les composites organiques (plastiques renforcés par des fibres continues ou discontinues) peuvent être affectés de pathologies plus ou moins gr...

In bubble assisted vacuum thermoforming, measuring pressure-induced mechanical strains through the stereo-digital image correlation (stereo-DIC) technique while shaping thermoplastic sheet requires consideration of an appropriate reference state of surface deformations. However, when the stereoscopic measurements can be only performed after the hea...

Biobased aromatic polyamide/organoclay (Cloisite30B, C30B) nanocomposites were melt‐compounded with reactive and nonreactive styrene–ethylene–butylene–styrene (SEBS) rubbers at different weight contents to form ternary and quaternary blends. The mechanical properties were investigated as a function of the blend composition. The elongation at break...

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...

Au cœur des thématiques de l’Industrie du Futur, l’Intelligence Artificielle (IA) est un domaine de R&D en pleine expansion dans tous les secteurs, et notamment dans celui du monitoring de l’état de santé des matériaux et de la maintenance prédictive des structures et installations industrielles in-situ. Dans ce domaine d’application, le parallèle...

Full-field measurement of principal mechanical strains via the stereo-digital images correlation technique (stereo-DIC) during thermoforming of thin thermoplastic sheets was recently reported as a potential method to control the wall-thicknesses under the assumption of material’s incompressibility. The accuracy of mechanical strains during forming...

Polymer composites were initially adopted and became popular in transportation sectors (primarily and massively in aerospace, then automotive and in a lesser extent railway industry) to manufacture structural and semi-structural parts driven by their superior strength and stiffness-to-weight ratio. Such market segments, where the lighter is the bet...

La présente invention a pour objet un matériau composite comprenant une phase fibrillaire et une matrice, la phase fibrillaire étant formée in-situ dans ladite matrice. De manière caractéristique, ladite matrice comprend un polymère de (co)polycarbonate A comprenant au moins des unités de répétition dérivées du 1,4:3,6-dianhydrohexitol, et ladite p...

At the request of the plastics industry (Federation of Plastics and Composites) as well as the Ministry of Industry and Research, this Centre was the first one established in France in 1983 for technological research and graduate students (MEng, MSc and PhD) training in the field of plastics processing and composites manufacturing. - Lab activity s...

This paper aims at checking the possibility of substitute metal by filled thermoplastic materials for making finned-tube Heat Exchangers (for HVAC applications, heat recovery …). The influence of low thermal conductivity of a filled polymer on the overall thermal performance of a compact finned-tube Heat Exchanger was numerically analyzed, via Comp...

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...

This work aims to analyse the influence of the fibre/matrix interface on the acoustic response of commingled yarn thermoplastic composites submitted to transverse tension and mode I fracture mechanics loading. For this purpose, different interfacial qualities were obtained by modification of the fibre reinforcement sizing and the matrix coupling. T...

The formulation of unsaturated polyester Bulk Moulding Compounds (BMC) or Continuously Impregnated Compounds (CIC) induces a variation of their reactivity or viscosity, which reflects the heterogeneity of the material batches produced. This experimental study has pointed out the benefits brought by an advanced process control of the injection mould...

De plus en plus présents, les composites doivent répondre à l'exigence de recyclage imposée par la réglementation. Mais le retraitement de ces produits en fin de vie constitue un véritable casse-tête puisqu'ils sont composés de matières aux propriétés différentes. Que ce soit pour séparer les fibres de la matrice polymères, préserver les caractéris...

Fabriquer des pièces plastiques allégées en grande cadence tout en maintenant un niveau de qualité élevé et une excellente reproductibilité de structure alvéolaire permet de limiter les coûts de production en abaissant les tonnages des presses utilisées mais aussi de réduire les quantités de matière tout en améliorant le bilan carbone par l’origine...

Acoustic emission (AE) is a passive non-destructive testing (NDT) technique, which can detect evolving damage in materials or structures submitted to mechanical loading. Therefore, free stress structures cannot be monitored by AE. Moreover, there are numerous applications where mechanical loading stimulation is not desirable as it may induce damage...

Bio-based poly(L-lactide)/poly(amide-11) blends (PLA/PA11, 80/20 w/w) and poly(L-lactide)/poly(amide-6) blends (PLA/PA6, 80/20 w/w) are processed by twin-screw extrusion followed by injection-moulding and key rheological parameters controlling their morphologie are investigated. The same work is done using the same PLA modified by a multi-step reac...

Bio-based polyamide 11 (PA11)–graphene nanoplatelets (GNP) nanocomposites with different filler concentrations were prepared by melt extrusion using a masterbatch dilution process. Graphene platelets are uniformly distributed into the polymer matrix as revealed by scanning electron microscopy. The incorporation of graphene significantly improves th...

Design of structural parts made of 3D textile reinforced materials demands deep understanding of different physical phenomena that must be accounted at the separate steps from manufacturing to exploitation. Complete process relies on numerical methods to resolve multi-scale material modeling and includes quantification of various manufacturing effe...

This paper focuses on the potential use of stereo-DIC in thermoforming conditions to monitor large deformations of softened thermoplastic sheets posteriori to the sagging phenomenon. The study concerns HIPS sheets which are softened by the radiative heat-transfer mode then stretched by inflation of compressed-air for 1.5 s to form a large and quasi...

This article focuses on the preparation of isolated soy protein plasticized by a glycerol and water mixture/poly[(butylene succinate)‐co‐adipate] blends by an original single step extrusion process. Prepared blends were injection‐molded and characterized for their molecular interaction, morphology, rheological, thermal, dynamic mechanical, and mech...

L’identification des lois de comportements des matériaux utilisés en thermoformage et, à terme, le développement de modèles prédictifs de ce procédé requièrent l’analyse fine des effets thermiques et mécaniques induits par les différentes phases de la mise en forme. Les techniques d’imagerie rapide s’avèrent particulièrement intéressantes.

A hybrid non-destructive testing (NDT) approach has been developed for structural composites damage monitoring using several NDT techniques. Three nondestructive techniques (acoustic emission, infrared thermography and digital image correlation) were used simultaneously, in-situ and in real time to assess damage in an aeronautical carbon/epoxy comp...

L’identification des lois de comportements des matériaux utilisés en thermoformage et, à terme, le développement de modèles prédictifs de ce procédé requièrent l’analyse fine des effets thermiques et mécaniques induits par les différentes phases de la mise en forme. Les techniques d’imagerie rapide s’avèrent particulièrement intéressantes.

An inverse method for determining the in-plane effective thermal conductivity of porous thermoplastics was implemented by coupling infrared thermography experiments and numerical solution of heat transfer in straight fins having temperature-dependent convective heat transfer coefficient. The obtained effective thermal conductivity values were compa...

Key relationships between foam morphologies and melt-state rheological parameters are here exposed for biobased poly(butylene-succinate) (PBS) and standard petrobased polyethylene (PE) foams processed by single-screw extrusion. Scanning electron microscopy followed by image analysis revealed cell diameters and densities in the range of 250–700 µm a...

La fabrication additive est un concept apparu il y a plus de 30 ans. A l’origine utilisée pour la fabrication de prototypes permettant de valider un concept ou un design, son usage a été étendu à la fabrication rapide d’outils (moules, outillages). Aujourd’hui, le terme regroupe un ensemble de technologies de fabrication, présentant un potentiel, p...

With the advent of the Internet of Things (IoT), smart connected objects implementing numerous sensors and complex diagnosis / communication accessories are multiplying. Their power supply requires renewable electrical power generation systems adapted to miniaturized low-amperage batteries of wearable electronic devices. Thus, new energy sources ar...

In the field of experimental mechanics, interest is more and more attributed to designing original single multiaxial tests which can exhibit heterogeneous mechanical responses for parameters identification. In fact, classical identification procedures of biaxial thermoplastic properties which rely on simple isotropic behavior obtained from uniaxial...

Développement d’outils expérimentaux et de méthodologies pour optimiser l’identification des paramètres matériaux in-situ.

The contribution of bioengineering to innovative applications: Materials of biological origin Founded in 2012, IFMAS (Institut Français des Matériaux Agro-Sourcés) is a private R&D firm with expertise in the chemistry of plant life and materials of biological origin. Its vocation is to carry out R&D programs oriented toward applications and perform...

Les polymères thermoplastiques peuvent, moyennant compoundage avec des charges conductrices adéquates et optimisation du design et de la compacité des échangeurs thermiques, se révéler des matériaux de construction intéressants, non seulement en termes d’efficacité thermique et de rendement énergétique, mais également d’allègement, de coût, de faci...

Un nouveau procédé d’imprégnation directe de renforts textiles en fibres de lin par une matrice thermoplastique permet de fabriquer à bas coût et avec des temps de cycles courts des composites biosourcés à hautes performances mécaniques.

L'invention concerne un procédé de transformation d'un polymère thermoplastique élastomère polycondensé, comprenant une étape d'extrusion du polymère thermoplastique élastomère polycondensé en présence d'eau. Le polymère thermoplastique élastomère polycondensé est notamment choisi parmi les copolyéther bloc amides, les copolyéther ou copolyester bl...

Les polymères à structure cellulaire obtenus par extrusion-moussage peuvent présenter des propriétés électroactives, ajustables via la microstructure induite par le procédé, intéressantes pour des applications dans le domaine des objets connectés, capteurs tactiles ou récupérateurs d'énergie.

Microfibrillar polymer / polymer composites constitute a particular kind of multiphase polymeric materials in which the minor phase is in the form of filaments dispersed in the continuous phase and behave like fibrillar meltable solid particles. Compared to traditional composites, the polymer/polymer composites are light weight recyclable materials...

This article aims to investigate the flexural creep behaviour as a function of temperature of long glass fibre polyamide 6.6 taking into account the thermal-oxidative degradation occurring during the test. The mould geometry has been chosen so as to reproduce some geometrical accidents (e.g. sharp frontal and tangential steps) occurring on industri...

This study is dedicated to the development of a numerical finite-element solution to determine the effective thermal conductivity of extruded polymeric foam with different levels of open and closed porosity. The implemented numerical method is derived from periodic homogenization techniques used for the simulation of laser welding of composite mate...

A novel static and fatigue modeling of composite structures has been developed by progressive damage simulation at the level of the equivalent (or homogenized) ply and direct post-treatment analysis respectively. The progressive damage mechanisms can be successfully modeled by taking into account the degradation of material properties at mesoscopic...

The energy harvesting efficiency of melt processed polyamide 11(PA11) films and its nanocomposites have been investigated as a function of filler type and content. In the present work, nanoclays have been used as structural modifiers in PA 11 matrix. Nanocomposites were prepared using layered clays namely Cloisite 20A, 10A and Na⁺by extrusion proce...

A hybrid non-destructive testing (NDT) approach has been developed to characterize composites damage using simultaneously bulk and guided ultrasonic waves, acoustic emission, and passive and active infrared thermography. Combining multiple NDT techniques makes it possible to optimize the diagnosis of a material's structural health.

Plastiques & Caoutchoucs Magazine, N°929, pp 46-48, 2016 Résumé Connaître le comportement rhéologique des mélanges de polymères et maîtriser leur mise en oeuvre améliore efficacement leurs performances mécaniques, sans pénaliser la masse et l'aptitude au recyclage. Contexte industriel - Méthodes d’élaboration des composites microfibrillaires -...

This paper focuses on the development and the validation of flexural modulus and flexural strength predictive models of long glass fibre reinforced polyamide 6.6 (PA66). Based on previous injection moulding optimization of 40 wt% long glass fibre PA66, a microstructure analysis was investigated on glass fibre reinforced PA66 by varying the paramete...

This paper aims at improving the mechanical behavior of biobased brittle amorphous polylactide (PLA) by extrusion melt-blending with biobased semi-crystalline polyamide 11 (PA 11) and addition of natural halloysite nanotubes (HNT). The structure and properties of PLA/PA11/HNT blends were studied in terms of morphological, thermal and mechanical pro...

Factories of the Future (FoF) are expected to implement new integrated design-manufacturing approaches to go towards so-called 'advanced manufacturing'. Actually, combination of additive manufacturing (AM, or 3D-printing) and topological optimization offer new opportunities to produce lighter products with lower environmental footprint. Fused Depos...