In recent years, new revolutionary paradigms generally indicated using the term Industry 40, have been conceived and are progressively applied in several manufacturing systems to achieve a smarter

Advanced robotics and additive manufacturing of composites: towards a new era in Industry 4.0

3D printing provides a new technical means for the preparation of functionally controlled continuous fiber reinforced composites (CFRCs) with variable fiber content. The constitutive model of 3D printed CFRCs with different fiber contents are the basis for establishing mechanical analysis models and design methods of functionally regulated CFRCs based on 3D printing. In this paper, stiffness and strength properties of 3D printed CFRCs with different fiber contents were systematically studied, and the mapping relationship between material properties and fiber content was obtained. The failure processes of 3D printed CFRCs under different loads were studied by microstructural morphology and interfacial performance analysis, revealing the formation mechanisms of the material properties. The constitutive model and finite element analysis method of 3D printed CFRCs were established by using the material properties of 3D printed CFRCs with different fiber contents. The mechanical analysis mode was used to predict and analyze the performance of functionally graded CFRCs with variable fiber content. The results show that the mechanical analysis mode can be used for the optimization design and mechanical analysis of functionally controlled CFRCs.

A constitutive model for 3D printed continuous fiber reinforced composite structures with variable fiber content

https://repository.tudelft.nl/islandora/object/uuid%3Abe719f17-ef0e-41a4-8fcd-ee7d641a59ae/datastream/OBJ/download

Using passive and active acoustic methods for impact damage assessment of composite structures

Thank you for reading composite airframe structures practical design information and data. Maybe you have knowledge that, people have search numerous times for their chosen readings like this composite airframe structures practical design information and data, but end up in malicious downloads. Rather than reading a good book with a cup of tea in the afternoon, instead they cope with some infectious virus inside their laptop.

Composite Airframe Structures Practical Design Information And Data

Guided wave SHM system for damage detection in complex composite structure

The paper proposes a mixed strain- and stress-based topology optimization method for designing the ideal geometry of carbon fibers in composite laminates subjected to either applied tractions or prescribed displacements. On the basis of standard micromechanical approaches, analytical elastic solutions for a single cell, assumed to be a Representative Volume Element (RVE), are ad hoc constructed by involving anisotropy induced by fiber orientation and volume fraction, also taking into account inter-laminar stresses and strains. The analytical solutions are then implemented in a Finite Element (FE) custom-made topology optimization-based procedure rewritten to have as output the best curves the reinforcing fibers have to draw in any composite laminate layer to maximize the overall panel stiffness or to minimize the elastic energy. To verify the effectiveness of the proposed strategy, different structures undergoing either in-plane or out-plane boundary conditions have been selected and theoretically investigated, determining the optimal fibers' maps and showing the related results in comparison to standard sequences of alternate fibers disposition for the same composites. Two optimized panels were at the end actually produced using an innovative Automated Fiber Placement (AFP) machine and consolidating the materials by means of autoclave curing processes, in this way replicating the fiber paths obtained from theoretical outcomes. As a control, two corresponding composite structures were also built without employing the fiber optimization strategy. The panels have been tested in laboratory and the theoretical results have been compared with the experimental findings, showing a very good agreement with our predictions and confirming the capability of the proposed algorithm in suggesting the arrangement of the fibers to obtain enhanced mechanical performances. It is felt that the hybrid analytical-FE topology optimization strategy, in conjunction with the possibilities offered by AFP devices, could pave the way for a new generation of ultra-lightweight composites for aerospace, automotive and many industrial applications.

Topology optimization-guided stiffening of composites realized through Automated Fiber Placement

Post-impact damage detection on a winglet structure realized in composite material

Composites world is in continuous evolution and there has been a progressive change in terms of manufacturing processes, passing from standard wet or prepreg manual layup to automated (preforming) technologies, with the objective to increase production rates and make cheaper manufacturing processes. This chapter deals with most recent advancements and applications of thermoplastic composites, focusing on the reasons why for aerospace sector, they are increasingly representing a more viable manufacturing solution for structural components. Starting from thermoplastic polymer structures and difference with respect to thermoset matrix based composites, the standard consolidation processes (autoclave/thermoforming) together with most promising automated and continuous out-of- autoclave manufacturing concepts and processes (Automated Fiber Placement/Automated Tape Laying, In Situ Consolidation, Continuous Compression Molding, Pultrusion), including assembling methods (Fusion/Welding), are illustrated. Furthermore, an overview on different recycling concepts related to thermoplastics and thermosets composites is provided. At last, an overview on the European thermoplastic development roadmap, supported by the EU’s Horizon 2020 Research and Innovation program (2014–2021) for the next generation of aircrafts, is illustrated.

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Thermoplastic Composites for Aerospace Applications

This work deals with the eectiveness of a multi-body approach for the study of the dynamic behavior of a fixed landing gear, especially the research project concerns the drop tests of the AP.68 TP-300 aircraft. First, the Digital Mock-up of the of landing gear system in a C.A.D. software has been created, then the experimental structural stiness of the leaf spring has been validated using the FEM tools MSC.Patran/Nastran. Finally, the entire model has been imported in MSC.ADAMS environment and, according to the certifying regulations, several multi-body simulations have been performed varying the heights of fall and the weights of the system. The results have shown a good correlation between numerical and experimental tests, thus demonstrating the potential of a multi-body approach. Future development of the present activity will probably be an application of the methodology, herein validated, to other cases for a more extensive validation of its predictive power and development of virtual certification procedures.

/pdf/drop-test-simulation-for-an-aircraft-landing-gear-via-multi-1y0dwokoux.pdf

Drop Test Simulation for An Aircraft Landing Gear Via Multi-Body Approach

An innovative hybrid thermoplastic manufacturing process has been investigated, which consists in carbon fibres reinforced poly(ether-ether-ketone) (PEEK) prepreg sandwiched between two amorphous polyetherimide (PEI) films. By using a laser-assisted automated fibre placement (AFP), a laminate is produced by the deposition of hybrid prepreg tapes, layer-by-layer without using autoclave. The temperature history control is required to ensure good consolidation throughout the part. This depends on the optical behaviour of the hybrid material, which is also subjected to the influence of process parameters. Before determining the optical properties of the new hybrid material, the correlation between these process parameters has been established based on the interaction of laser spot with PEI film and PEEK/carbon fibres tape. Then, the thermal distribution in the laminate is obtained via an optico-thermal model and validated with experimental results. Finally, a heating law for the AFP process is established using iterative numerical simulations.

Marco Barile

Papers

Topology optimization-guided stiffening of composites realized through Automated Fiber Placement

Post-impact damage detection on a winglet structure realized in composite material

Thermoplastic Composites for Aerospace Applications

Drop Test Simulation for An Aircraft Landing Gear Via Multi-Body Approach

Automated fibre placement process for a new hybrid material: A numerical tool for predicting an efficient heating law