Ongoing research projects
IMMC
Ongoing research projects in iMMC (March 2023)
This a short description of research projects which are presently under progress in iMMC.
Hereunder, you may select one research direction or choose to apply another filter:
List of projects related to: Processing and characterisation of materials
 | DeltaT Researcher: Valentin Marchal-Marchant Supervisor(s): Pascal Jacques obtained his degree in engineering in materials science from the Université catholique de Louvain in 2011. Then, he accomplished his PhD under the supervision of prof. Pascal Jacques, on the study of Physical Vapor Deposition of thick copper films on steel. His research is now focused on the development of thermoelectric materials and thermoelectric generators for energy harvesting and passive electromechanical systems. It aims at using common and non-toxic materials to generate electrical power from thermal gradients. Nowadays, attention is put on large scale applications owing to more than 7 years of research about thermoelectric materials leaded in IMAP. The big challenge of this topic is the development of new tools and equipments for material production and assembly, and specific characterization methods. Such a wide range of different tasks can only be achieved thanks to the versatility of technical and scientific expertises of the IMAP team members as well as Lacami support. |
 | Researcher: Laurine Choisez Supervisor(s): Pascal Jacques The association of different plastic deformation modes (TRIP, TWIP) induces unmatched levels of mechanical properties in a new beta metastables titanium alloys family. A hardening beyond the theoretical limit is especially noticed, together with a uniform deformation 3 to 4 times higher than the one in a classic TA6V alloy and a yield stress superior of 30 percent to the one in a TWIP alloy. A positive synergy is thought to exist between a high hardening and the damage resistance and toughness of such materials. My thesis will consist in the study of the damage resistance and the toughness of several beta metastables titanium alloys with different prevailing plastic deformation mechanisms in order to highlight the mechanism responsible of the post-necking deformation properties. |
 | Coupled mechanical-electrical effects in highly strained Ge thin films Researcher: Marie-Stéphane Colla Supervisor(s): Thomas Pardoen Graduated in chemical and materials science engineering at the Université catholique de Louvain in 2009 (Belgium). Then, under the supervision of Prof. Thomas Pardoen (iMMC) and Prof. Jean-Pierre Raskin (ICTEAM), she accomplished a PhD on the study of the mechanical properties of thin films, more specifically on the plasticity and creep of freestanding nanocrystalline Pd films. The lab-on-chip technique developed previously at the UCL was adapted to deform Pd thin films. After the PhD, she worked for more than two years at the CRM Group in Liège on the development of industrially viable thin film solar cells on steel. From June 2016 to September 2018, she is back at the UCL as a research engineer involved in projects dealing with the understanding of fracture behaviour of high strength steels under a wide range of strain rates. In 2018, she received a 'Chargée de recherches - FNRS grant' and is now working on coupled mechanical-electrical effects in highly strained germanium thin films. Germanium is a promising material for optoelectronic device owing to its compatibility with the standard complementary metal-oxyde-semiconductor (CMOS) technology and to the possibility to convert it into a direct bandgap semiconductor by straining it. |
 | Locoted Researcher: Geoffrey Roy Supervisor(s): Pascal Jacques Geoffrey holds a Master in Mechatronic Engineering (2010) and a PhD in Engineering (2015) from the Université catholique de Louvain where he works as a senior researcher at the Institute of Mechanics, Materials and Civil Engineering (iMMC). Within the Division of Materials and Process Engineering (IMAP), his research is focused on the development of new thermoelectric materials and systems for a range of applications going from industrial waste heat recovery to autonomous powering of smart sensors. In his research, he pays particular attention to the development of new solutions that present improved both technical and economical profiles in order to facilitate the emergence of these solutions out of the lab. This research is followed by several companies such as: Drever International, AGC Glass Europe, Carmeuse or Engie. |
 | LongLifeAM & MultiMat3D (additive manufacturing) Researcher: Camille van der Rest Supervisor(s): Pascal Jacques, Aude Simar Camille van der Rest completed her PhD thesis on the optimisation of Heusler Fe2VAl-based thermoelectric compounds through innovative metallurgical processing in 2015. It was under the joint supervision of Prof. Pascal Jacques and Prof. Aude Simar. Her research topics now concern additive manufacturing, friction stir processing and thermoelectric materials. Concerning additive manufacturing, the main contributions are on the characterisation and optimisation of the microstructures and the mechanical behaviour of Al parts obtained by Laser Powder Bed Fusion and the developpment of new materials for additive manufacturing. The link between the process parameters and the final microstructure/properties is a key issue. The optimisation of the post-treatments, both thermal treatments and Friction Stir Processing (FSP), is another of her research topics in order to reach improved mechanical properties. Finally, multi-material additive manufacturing is also studied, in order to understand the influence of both metallic alloys and their interactions (diffusion, reaction,...) on the final microstructures and properties. On another hand, Camille developed, together with Prof. Aude Simar and Prof. Pascal Jacques, a novel Friction Melt Bonding (FMB) process in order to weld aluminium alloys and steels. This process is still under development thanks to the collaboration with other researchers of IMAP. Concerning thermoelectrics, the main objective is the development of low-cost, non-toxic, and powerful materials that could be used in large-scale industrial applications of heat recovery. In addition, she studies some fundamental aspects in order to improve the performances of such materials, i.e. ordering phenomena in off-stoichiometric Fe2VAl-based Heusler compounds. It is essential to make the link between (innovative) manufacturing processes, microstructures and the functional properties of these TE materials. |
 | TECCOMA Researcher: Pierre Bollen Supervisor(s): Thomas Pardoen graduated as engineer in chemistry and materials science at Université catholique de Louvain (Belgium) in 2010. In 2015, he obtained at UCLouvain his PhD thesis entitled hierarchical hybrid materials combining wideband electromagnetic absorption and mechanical performance, funded by a FRIA grant. After working one year as a support engineer in the field of extended finite element modeling, he came back at the UCLouvain as a senior researcher involved in applied research projects in collaboration with industry. He is currently dealing with erosion coating on CFRP as well as thermal and electromagnetic management in electrical power converter. |
 | MACOBIO (MAtériaux COmposites BIOsourcés) Researcher: Vincent Destoop Supervisor(s): Thomas Pardoen made his PhD on the adhesion of tooth-filling materials to the dentine. He’s now working on composite materials to replace metals in aircraft applications. He takes part to projects studying the mechanical behavior of composite materials (mainly polymer matrix reinforced with long fibers) which are new candidate materials for modern planes. Recently, his research was oriented on biosourced composites. His investigations focus on the bulk, cracking, impact and adhesion properties. |
 | Researcher: Catherine Doneux Supervisor(s): Thomas Pardoen graduated as Civil Engineer at University of Liege in 1992. She began her career with a first experience on the assessment of an existing prestressed railway bridge. Thanks to several FNRS grants, she obtained a PhD degree in the domain of steel-concrete composite structures under seismic action in 2002 and was involved in several researches on paraseismic design at ULg until 2005. After some career break, she joined UCLouvain in December 2008 to take part to the development of new composite activities related to various applied research projects in collaboration with the industry (aeronautics) Her main fields of expertise are the mechanical characterization of composite materials by mechanical testing, the quality control of the standardised tests and the development of new tests. She has also some experience in fatigue testing, damage characterization and fracture mechanics. She is currently working on the preforming of composite thermoset prepreg fabrics. |
 | MONACO Researcher: Audrey Favache Supervisor(s): Thomas Pardoen obtained a PhD degree in the domain of process control in 2009 at Université catholique de Louvain (Belgium), after having graduated there as chemical engineer in 2005. Since then, she is working as a "senior" researcher on several applied research projects in collaboration with the industry in the domain of mechanics of materials. More particularly, she is interested in the link between the mechanical properties of the individual components of a complex system and the global mechanical response of this system. She applied this approach to the framework of tribology and contact mechanics for understanding the scratch resistance of coatings and multilayered systems. Her work covers both experimental aspects and finite element simulations. |
 | WAALU: wire arc additive manufacturing (WAAM) of high strength aluminium alloys Researcher: Matthieu Baudouin Lezaack Supervisor(s): Aude Simar The WAALU project aims at manufacturing structures in high strength aluminium alloys by wire arc additve manufacturing (WAAM). The WAAM application on aluminium alloys is currently limited to easy to weld alloys (Mg enriched 5xxx series). The WAALU project is investigating the feasability of deposing high strength alloys like 2xxx and 7xxx series by WAAM technique. The current challenges are the need of manufacturing aluminium wires in the targetted series and the identification of the WAAM working parameters to avoid deposition defects in the built pieces. Step by step, the project proposes a methodology for processing the high strenght alloys by WAAM, with extensive characterization of the obtained microstructures. Mechanical performances of printed parts are extracted in all configuration, in order to achieve excellence in WAAM manufacturing in Belgium. |
 | Influence of defects on the life of biomedical implants Researcher: Maïté Croonenborghs Supervisor(s): Pascal Jacques, Thomas Pardoen Implants are devices aiming to support, help, or even correct biological structures. However, with time, some of these implants show aging problems. The roots of these problems can have numerous explanations. In some cases, the body reacts to the presence of a foreign body, and this can lead to health risks. Sometimes, the material can show, with time, signs of weakness. Later on, these defects can lead to the failure of the implant. In the case of permanent stent implants, the presence of a foreign body in the blood vessels can lead to restenosis or late thrombosis. This is why bioresorbable stents are nowadays developed. These stents should support the vessels during their healing period and dissolve in an inoffensive way afterward. Iron-based alloys are investigated for their appropriate mechanical properties but their degradation rate is too low. One investigated solution is to increase surface roughness to dissolve faster the implant. The effect of this roughness on the expansion process has not been analyzed for now. The case of growth rods shows that the material itself can lead to implant failure. These rods are placed, during surgery, along the spine of scoliotic children. They aim to support the spine and help it to straighten back. However, fracture events occur in 36% of the patients. During the surgery, the rods are bent to fit the natural shape of the spine. The tools employed for this process can introduce some indentation marks on the surface of the rods and decrease their fatigue lifetime. From these case studies, it is observed that the completion of an implant (i.e. stent implantation process) or its lifetime (i.e. growth rod failure) can be affected by its surface state. This research will therefore focus on the imperfection sensitiveness of such devices. Various kinds of defects are introduced at the sample surface. To understand the influence of these defects on the mechanical properties, these samples are tested and compared. |
 | Multi-material 3d additive manufacturing Researcher: Antoine Hilhorst Supervisor(s): Pascal Jacques High entropy alloys (HEAs) are a new family of metallic alloys. In contrast to conventional alloys, HEAs have multiple principal elements e.g. the equiatomic "Cantor" alloy CrMnFeCoNi. Alloys in this range of chemical composition have gathered attention only recently. From what was observed in conventional alloys, it was expected that HEAs microstructure be composed of several intermetallic phases but some systems are surprisingly single phase solid solution. Moreover, such single-phase alloys have excellent mechanical properties. For instance, CrMnFeCoNi possess a large fracture toughness, which increases with decreasing temperature, putting this alloy on par with the current best alloys used for cryogenic applications. As such, the objective of the thesis is to understand the underlying mechanisms responsible for the observed macroscopic behavior of such alloys. The thesis aims to answer several questions such as: What are the mechanisms responsible for the increase in ductility, strength, and fracture toughness with decreasing temperature? What high-throughput methodology would be able to screen the vast range of possible chemical composition of HEAs for high performance alloys? To understand the deformation mechanisms, several HEAs will be fully characterized from casting to mechanical testing. For the fracture toughness measurements, the essential work of fracture method will be employed as it is best suited for ductile thin sheets than compact tests. Diffusion multiples will be explored as a possible high-throughput method, as the presence of composition gradients allows the simultaneous characterization of a range of composition by techniques such as EDX, EBSD and nano-indentation. |
 | A microCT-based approach for high-resolution characterization of biodegradable metallic intravascular stent materials Researcher: Lisa Leyssens Supervisor(s): Greet Kerckhofs, Pascal Jacques The goal of my research project is to assess different potential biodegradable metallic intravascular stent materials using high-resolution 3D microfocus X-ray computed tomography (microCT). In a first step, the optimization of microCT and contrast-enhanced microCT (CECT) for the characterization of the 3D microstructure of different blood vessels is performed (aorta, femoral artery, vena cava) in different species (rat, porcine, human). Then, this technique is applied to study the degradation behaviour of potential materials for biodegradable metallic intravascular stents. Structural properties are investigated. They are critical because they will influence the mechanical and in vivo behaviour of the stents. The materials (in the shape of wires) are screened to analyze the corrosion and surface changes, before and after immersion tests (in vitro part) and before and after implantation in rat arteries to additionally study interactions between the tissue (artery) and the metal (in vivo part). |
 | Improving the properties of glass fiber reinforced acrylic thermoplastic resin based composites Researcher: Sarah Gayot Supervisor(s): Thomas Pardoen For the manufacturing of continuous fiber reinforced thermoplastic composites (CFRTP), certain monomers can be infused through glass fabric and then polymerized in situ, in order to make a thermoplastic composite part. However, defects - e.g. porosity - can occur in the material, due to the thickness of the laminates and the shrinkage of the resin matrix during polymerization. Such phenomena must be understood, as well as their effects on the mechanical properties of the final composite part. The originality of this work lies in the very nature of the polymeric matrix used for manufacturing the composite parts, which is thermoplastic instead of thermoset. Little is known about the behaviour of such thermoplastic composites, especially at a microscopic scale. During this PhD, we will try to understand how defects occurring in the material can influence the structural properties of the CFRTP, and we will try to mitigate (or at least control) the incidence of such defects. This will imply a better knowledge of how usual characterisation techniques can be applied from thin to thick composite parts. In particular, digital simulation will be used so as to predict the properties of thick composite parts from those of thinner samples. |
 | Development of thermo-tensile nano devices operating ex situ or in situ in transmission electron microscopes (TEM) Researcher: Alex Pip Supervisor(s): Hosni Idrissi The main goal of my research project is to develop modern miniaturized devices dedicated to quantitative small-scale thermo-tensile testing in-situ inside a transmission electron microscope. These unique devices will be used to investigate the effect of T on the plasticity/failure mechanisms in selected materials, nanocrystalline palladium films and olivine. My project builds up on already existing MEMS devices, namely the commercial Push-to- Pull from Bruker.Inc and UCLouvain’s ‘lab-on-chip’ nano tensile testing devices. Currently, those devices are limited to room temperature experiments. My work will be dedicated to the integration of heating systems inside these two devices, in order to heat samples up to hundreds of °C. This will allow performing in-situ TEM thermo-tensile tests on Pd films and olivine samples where the coupling between tensile loading and heating could lead to unprecedented results regarding the effect of T on the mechanical response and the plasticity/failure mechanisms. This project has a direct application in the field of geology, as one of the selected material is olivine, the material that makes up most of the upper part of the Earth’s mantle. Thermo-tensile testing of olivine at the micro/nano scale will bring crucial data about its rheology under conditions similar to the Earth’s mantle. This part of the project involving olivine will be performed in close contact with prof. Patrick Cordier and his team at UMET (Université de Lille). The other selected material is Pd, a material that is well known by the UCLouvain’s IMMC researchers used here as a benchmark. I will mostly work within the WINFAB platform, where I will develop and build the new thermo-tensile devices using the nanofabrication equipment. As theses devices are expected to be used in-situ inside a TEM, I will also partly work at the EMAT research center (UAntwerpen). |
 | Impact of membrane characteristics on enzyme reactivity and co-crystallization Researcher: Sara Chergaoui Supervisor(s): Patricia Luis Alconero The project focuses on the enantioselective biocatalytic synthesis of high-value chiral amines. A combined reaction-purification process based on membrane technology and using enzymes will be developed. As opposed to classical batch and multi-step processes, such an integrated approach would allow (i) maintaining the enzyme in the reactor, (ii) intensifying the production of high added-value chemicals, and (iii) recover a highly pure co-product. Novel membranes will be developed and the effect of their composition and structure on the final performance will be studied. |
 | Analysis and understanding of the damage and fracture mechanisms in advanced high strength steels for automotive applications Researcher: Thibaut Heremans Supervisor(s): Pascal Jacques, Thomas Pardoen The environmental challenge the world is facing today is driving car manufacturers to limit their vehicule weight in order to reduce their fuel consumption. As a consequence, steels with higher specific strength performances are being constantly developed, while insuring that proper ductility and toughness levels are retained to allow for forming operations and passengers safety. Lately, the so-called "third generation" of advanced high strength steels (AHSS) has emerged, among which one finds the Quenching & Partioning (Q&P) steels. These Q&P steels demonstrate an excellent combination of ultimate tensile strength (UTS = 1500 MPa) and adequate ductility (TE = 18%). Nevertheless, their fracture properties and the underlying mechanisms are still not fully understood and start raising concerns as the strength levels of these steels increase. Indeed, recent studies have highlighted a shift in failure mechanism, from ductile to brittle, depending on the loading conditions. Although often left behind strength and elongation, toughness issues constitute essential stakes not only for ever more demanding applications but also for forming processes during which edge cracking is a key concern. The objective of my research project is to investigate the failure properties of these Q&P steels in order to understand how microstructural and micromechanical parameters influence the competition between three possible mechanisms : ductile flat, ductile slant and brittle intergranular. |
 | Advanced Characterization of the 3D Morphology of the Bone-Tendon Interface and the Relationship to the Functional Properties Researcher: Arne Maes Supervisor(s): Greet Kerckhofs Within my research project I aim to develop insights in the morphology and the structure-function relationships of the bone-tendon interface. To this end, contrast-enhanced microCT (CE-CT) will be applied for advanced structural characterization. A better understanding of this complex biological tissue is believed to greatly improve the probability of success of regenerative strategies aiming to treat injuries of the bone-tendon interface. |
 | Development and charactrisation of a Fe2VAl-based transverse thermoelectric module built by additive manufacturing Researcher: Mathieu Delcroix Supervisor(s): Pascal Jacques The aim of my thesis is to study and optimise an innovative alternative to classical thermoelectric generators according to different aspects : geometry, materials and manufacturing processes. More specifically, it consists in implementing and optimising a Fe2VAl-based transverse thermoelectric generator with an optimize internal topology built by multimaterial additive manufacturing. The main scientific issues that will dictate the experimental approaches and the modelling steps consist in : (i) understanding the transverse thermoelectric effect and its experimental study coupled with a topological optimisation (since existing studies are mainly theoretical only); (ii) the analyse of the microstructural characteristics resulting from the additive manufacturing on the electrical and thermal properties of the Fe2VAl compound (what has not been done so far), but also of the other compounds that are needed in case of multimaterial additive manufacturing; (iii) optimising the characteristics of a functional transverse thermoelectrical generator in function of the operating conditions. |
| Micromechanics of crystallization of thermoplastic matrices in the interfiber regions of high-toughness composites Researcher: Sophie Vanpée Supervisor(s): Thomas Pardoen A major effort is being made all over the world by industrial and research actors to lead the technological mutation of the field of advanced continuous fibers polymer composites from the current use of thermosetting matrices to thermoplastic ones which gather economic (increased production rates), environmental (recyclable) and performance advantages (tougher matrices). However, until recently, this transformation was strongly hindered by processing difficulties. Today, a precise prediction of the behavior of these materials based on the processing conditions becomes essential for many actors, such as the company Solvay, the industrial partner of the present thesis. It is in this context that the thesis will be carried out. The objective of the STOUGH project is to unravel the influence of the composite microstructure on the kinetics and morphology of crystallization within the matrix, particularly in the neighborhood of fibers, in order to evaluate their influence on mechanical properties of the matrix and, hence, of the composite. The project is thus intrinsically multi-scale, which necessitates a combination of analyses at the different levels of the composite system, from its constituents themselves to the unidirectional (UD) ply level and eventually to the macroscopic composite. The main questions are around the positive or negative impact of the conditions and the type of crystallization on the fracture toughness via local damage or decohesion of the fibers, as well as on the transfer of these effects to the macroscopic scale and the properties of use. To do so, it is necessary to understand what makes the behavior of the semi-crystalline polymer confined between fibers and the non-reinforced version of the same polymer different, and how factors related to transcrystallization condition the local mechanical behavior. Does the crystal morphology induce a local softening of the strength or the opposite? Are macroscopic constitutive models adaptable to this scale? Do the local internal stresses affect the first order strength of the interfaces? These are some of the major scientific questions that motivate the fundamental side of this project and justify the framework of a PhD thesis in collaboration with Solvay. The thesis will be based on an innovative methodology relying on the use of the appropriate experimental methods for each level of investigation. For instance, it will combine atomic probing and nanoindentation for the nano- and microscopic characterization of the matrix, fiber-matrix interface properties measurements, image correlation analyses at the scale of the representative volume of the UD ply as well as macroscopic tests at the coupon level. Additionally, the project will also include the specimens processing and manufacturing steps, as well as numerical aspects to incorporate the acquired knowledge in existing models. |