https://popups.uliege.be/esaform21/index.php?id=2337 Index terms fr 0 https://popups.uliege.be/esaform21/index.php?id=3844 Hybrid structures made of fiber-reinforced plastics (FRP) and metals are currently in focus of research and industry to develop weight reduced and functional optimized components for lightweight solutions. Manufacturing processes were adapted and developed to produce components based on hybrid materials with high economic efficiency. The cutting process is used to pre-assemble the semi-finished products or to post-process the edges of consolidated parts. The mechanisms of damage edge behavior and possible cutting qualities on these parts are not investigated jet. To close this knowledge gap and to support the future application of hybrid FRP-Metal-Laminates different cutting procedures were studied. This paper shows the process related dependences on the failure behavior of two dimensional specimens. The failure modes are described via quality characteristics like surface roughness, trueness and precision of the cut as well as influences of aging processes. In the end optimized parameter for each process are shown and compared under technical and economic criteria for large scale production. In the scope of this work an experimental study of piercing of glass and carbon fiber reinforced thermoplastic with different steel and bonding agents at different cutting sequences were performed. It was shown that the cutting edge geometry significantly differs. Possible mechanical explanations of the dependencies were formulated. Also the accuracy of the cuts was evaluated which showed a higher accuracy for the steel component. The measurements on the surface roughness could not show any dependencies and relations. Mon, 29 Mar 2021 14:49:59 +0200 Fri, 07 May 2021 11:32:38 +0200 https://popups.uliege.be/esaform21/index.php?id=3844 https://popups.uliege.be/esaform21/index.php?id=1580 Composite materials can be produced by several technologies, such as Liquid Composite Manufacturing (LCM). In this technology, a fabric can be formed by highly double curved punch geometries. During its forming, the fabric is submitted to several deformations and mechanical stresses, like biaxial tensile stress, shear, bending, compaction and friction. The cumulative effect of these stresses leads to the appearance of different types of defects such as wrinkles, buckles, sliding, etc. These defects may have a significant influence on the mechanical properties of the final composite materials. In order to understand the forming mechanisms of these defects, as well as their effect on the behavior of composite materials, an experimental machine was designed and built. The aim of this machine is to generate different types of defects with controlled and adjusted amplitudes (calibrated defects), in samples of a fabric. These samples are then used to manufacture composite samples with calibrated defects, by an LCM process. The defected composite samples are then tested and compared with composite samples without defects. The obtained results have identified the experimental parameters corresponding to the appearance of different types of defects. Mon, 22 Mar 2021 20:14:18 +0100 Mon, 05 Apr 2021 18:16:57 +0200 https://popups.uliege.be/esaform21/index.php?id=1580 https://popups.uliege.be/esaform21/index.php?id=4017 Polymer-based AM methods are the most mature additive technologies for their versatility and variety of products obtainable. The addition of fibre reinforcement can also confer to the manufactures produced good mechanical properties. Unfortunately, several applications are still precluded because polymers cannot guarantee appropriate electrical conductivity, erosion resistance and operating temperature. Aiming to overcome these issues, the metallization of the surfaces emerges as a possible solution. Unfortunately, thermoplastic polymers exhibit thermosensitive behaviour and run the risk of being damaged when traditional metallization techniques, which require the melting of metal powders which will act as a protective coating. For this reason, studies have focused on Cold Gas Dynamic Spray, an additive manufacturing technology, which exploits kinetic energy to favour the adhesion of metal particles rather than the increase in temperature. In this work, a first attempt is made to verify the feasibility of cold spray coatings on 3D printed composite substrates, produced by means of Fused Filament Fabrication (FFF) technique. FFF technology allows the deposition of two different types of filaments by using a double extruder. These composite fibres within 3D printed parts manage to give the object a resistance comparable to that of a metal part with lower production cost and a high degree of automation. These structures, made of ONYX, a Nylon matrix in which short carbon fibres are dispersed, and reinforced with long carbon fibres, are designed to better fit the CS deposition. Aluminium coatings have been produced and a characterization campaign has been carried on. Tue, 30 Mar 2021 10:01:16 +0200 Tue, 30 Mar 2021 10:26:30 +0200 https://popups.uliege.be/esaform21/index.php?id=4017 https://popups.uliege.be/esaform21/index.php?id=2335 Automated fiber placement processes could be combined with additive manufacturing to produce more functionally complex composite structures with more flexibility. The challenge is to add functions or reinforcements to PEEK/carbon composite parts manufactured by automated fiber placement process, with additive manufacturing by fused filament fabrication. This consists of extruding a molten polymer through a nozzle to create a 3D part. Bonding between polymer filaments is a thermally driven phenomenon and determines the integrity and the final mechanical strength of the printed part. 3d-printing high performance polymers is still very challenging because they involve high thermal gradients during the process. The purpose of this work is to find a process window where the bonding strength is maximized between the composite laminate and the first layer of printed polymer, and inside the printed function as well. Experimental measurements of the temperature profiles at the interface between a composite substrate and 3d-printed PEI under different processing conditions were carried out. The interface was observed using microscopic sections. The methodology for studying the impact of printing parameters on the cohesion and adhesion of printed parts with a composite laminate is described. This work provides insights about the influence of processing conditions on the bond formation between high-performance polymer surfaces. It highlights the importance of controlling the thermal history of the materials all along the process. Tue, 23 Mar 2021 16:58:33 +0100 Tue, 30 Mar 2021 10:21:28 +0200 https://popups.uliege.be/esaform21/index.php?id=2335