Abstract

Nowadays, manufacturing of composite parts using out-of-Autoclave (OoA) processes is gaining importance because it allows a reduction of initial investments and recurring costs. Among these technologies, the consolidation of out-of-autoclave prepregs using vacuum bag only technologies (VBO) is proven to provide high-quality composite structural parts without the need of autoclaves.  OoA prepregs are designed to be semi-impregnated creating engineered channels within the tows to evacuate internal air or volatiles generated during the cure cycle. The aim of this work is to understand and explain the void formation mechanisms, their spatial distribution and transport mechanisms during the consolidation of OoA prepregs using vacuum bag only methods. This work includes parallel studies carried out using X-ray computed tomography (XCT) to determine the most important factors for air removal process in laminated composites produced by hand lay-up (HLU) and automated fiber placement (AFP). A big challenge is the accurate monitoring of the evolution of porosity during composite curing, which has not been done so far and even less with a 3D visual technique. This combination of monitoring the dynamics of pore evolution by laboratory XCT and synchrotron tomography (SXCT) at different resolutions during a cure process will provide a profound understanding of the pore evacuation process which is strategic for the further development of OoA materials.

Abstract

The transport sector has exerted and continue to be the driving force for the development of new materials and lightweight solutions. The present study focuses on the work developed in a European project (CARBODIN https://carbodin.eu/) where one of the main objectives is to develop innovative and affordable solutions for advanced car body shells. Thus, contributing to the development of the next generation of passenger trains that will be lighter as well as more energy- and cost-efficient. Composite materials appear to be one of the most promising candidates to attain these ambitious targets. Therefore, new strategies to achieve greater automation are presented as novel manufacturing routes and offer a cost-effective industrial solution. 

This study has allowed the integration of unconventional technologies, such as AFP, within conventional production systems, such as VIP, which is the key to developing sustainable units, overcoming the common difficulties associated with processing and achieving the modularity of the manufacturing process and the reduction of the weight of the final rail structure. For this reason, a comparison of the manufacture of both monolithic composites and sandwich structures have been obtained through the VIP process, manufactured in an automated and manual way.

Several automated approaches have been studied, with the choice of the robotized lay up of bindered dry fibers. An out of autoclave manufacturing was assisted through different monitoring technologies such as resin arrival sensors and thermography in order to ensure high quality components.

Abstract

The transport sector has exerted and continue to be the driving force for the development of new materials and lightweigth solutions. The present study focuses on the work developed in a recently completed European project (CARBODIN https://carbodin.eu/) where one of the main objectives is to develop innovative and affordable solutions for advanced car body shells. Composite materials appear to be one of the most promising candidates to attain these ambitious targets. However, to overcome the cost barrier as well as meet additional railway requirements, new strategies such as process integration and novel manufacturing routes are needed, which will offer a cost-effective industrial solution. The case study corresponds to a C-Groove insert used as an anchoring point to hang passenger seats off the car body side walls, to fix Interior Panels or luggage racks. To improve this design, a trendsetting design was developed to integrate composite C-Grooves to Composite sidewalls. This work will display the details of such design as well as the optimal manufacturing strategy to achieve it. An out of autoclave (OoA) manufacturing process was assisted through different monitoring technologies such as resin arrival sensors and thermography to ensure high quality components. Additionally, a multi-material approach based on 3D printed technologies has been tackled. A thorough analysis of the joint has been performed and different integration approaches have been explored by designing co-cured and co-bonded manufacturing stages. Finally, several demonstrators have been made and tested to define the most promising integration approach and scaling up yet again to a larger demonstrator.

Abstract

The transport sector has exerted and continue to be the driving force for the development of new materials and lightweight solutions. The present study focuses on the work developed in a European project (CARBODIN https://carbodin.eu/) where one of the main objectives is to develop innovative and affordable solutions for advanced car body shells. Thus, contributing to the development of the next generation of passenger trains that will be lighter as well as more energy- and cost-efficient. Composite materials appear to be one of the most promising candidates to attain these ambitious targets. Therefore, new strategies to achieve greater automation are presented as novel manufacturing routes and offer a cost-effective industrial solution.

This study has allowed the integration of unconventional technologies, such as AFP, within conventional production systems, such as VIP, which is the key to developing sustainable units, overcoming the common difficulties associated with processing and achieving the modularity of the manufacturing process and the reduction of the weight of the final rail structure. For this reason, a comparison of the manufacture of both monolithic composites and sandwich structures have been obtained through the VIP process, manufactured in an automated and manual way. Several automated approaches have been studied, with the choice of the robotized lay up of bindered dry fibers. An out of autoclave manufacturing was assisted through different monitoring technologies such as resin arrival sensors and thermography in order to ensure high quality components.

Abstract

In the present study will show the concept of FOREST project which will contribute to the decarbonisation of the transport sector by developing and implementing innovative bio-based polymers & additives and recycled carbon fibres.

FOREST will develop novel lightweight multifunctional biocomposites as a competitive alternative to conventional composites. New chemistries will be developed based on bio-based materials (reactive and nonreactive polymeric systems and fire-retardant additives) in combination with fully recycled carbon fibre and EMI particles.

These biocomposite candidates will be obtained using one-shot manufacturing techniques, involving out-of-autoclave (OOA) processes to build and test prototypes (TRL5) with improved multifunctional properties (mechanical resistance, fire-retardant, EMI-shielding) for transport applications.