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Currently, worldwide, many nations are paying close attention to the improvement and optimization of the usage of recycled materials in the building sector. The increase in the raw materials and the increased environmental awareness have gained considerable importance on a global scale. In road engineering, the waste material is used for the design and construction of pavements. Ecology, energy efficiency, profitability and significant reduction of the construction time are the primary drivers of this proposal. However, social and legislative aspects have prevented these types of procedures are implemented successfully in most developing countries. In this article, we analyze some of the main trends in the use of waste materials for the design and construction of pavements.

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Due to the environmental challenges the aeronautical industry is facing, the development of recyclable aeronautical chemistries have recently raised huge interest. Within this context, different alternatives are being considered with the aim of obtaining new resins with current thermoset resin chemical and mechanical performance, while showing reprocessing, repairability and recyclability capabilities, like thermoplastics.

New vitrimer resins, based on dynamic covalent chemistry, become a very attractive alternative to combine the main advantages of aeronautical thermosets (processing conditions / temperature, means, properties…) and thermoplastics (recycling, welding…). Therefore, they can be the solution to overcome the current limitations of thermoset epoxy resin, which is widely used in composite airframe.

This project, framed within the national funding PTA (Plan Tecnológico Aeronáutico), was focused on the preliminary development of aeronautical vitrimer resin for composite airframe. It was proposed as continuation of the EU Horizon 2020 consortium AIRPOXY led by CIDETEC, where a first generation of aeronautical RTM vitrimer was developed and characterised, while a second generation vitrimer development was only started. This chemistry is based on the use of dynamic aromatic disulfides as hardener.

In the first 2021 project phase, following key activities were performed:

• Definition of targets or reference values for aeronautical infusion resin

• Second generation of infusion vitrimer: development completion and characterization

• Flat CFRP laminates with second generation vitrimer: production and thermoforming trials.

Next steps of the project in 2022 and 2023, will be focused on developing, evaluating and demonstrating an aeronautical prepreg based on vitrimer resin with higher Tg in line with current aeronautical resin values.

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The railway industry seeks to increase the capacity of the railway system, providing flexibility to align capacity and demand, increasing availability, reliability and energy efficiency by reducing the life cycle cost (LCC), improving passenger comfort and increasing the attractiveness of rail transport.

One of the lines of action to tackle the aforementioned challenges is the introduction of new lighter bodies and/or running gear structures, as both of these are among the heaviest components of the train. The potential weight savings (approximately 30 % and 50 %, respectively), and the use of new materials and processes in structures will result in reduced energy consumption, lower inertias, reduced track wear, and increased capacity to carry higher payloads.

This article will present the development of a carbon fiber single axle running gear frame including design, calculation and testing, achieving a 50% reduction in weight while maintaining the performance of current steel structures.

This project is within the Shift2Rail initiative, it is part of PIVOT and PIVOT2 Project. It has received funding from the European Union's Horizon 2020 program under grant agreements 777629 and 881807.

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Our latest generation aircraft are more efficient by design, lighter and emit on average 25% less CO2 than previous generation aircrafts. Lightweight materials like composites have contributed significantly to reach the current emissions levels, like the A350 with more than 50% of structural weight made of composites. However, composites drive also the environmental footprint of the aircraft life-cycle without considering the operational phase, involving currently important drawbacks in terms of energy consumption and waste recycling. The transition towards a composite circular economy needs to be anticipated due to the aviation sector de-carbonization challenge as well as the regulation evolution. This transition will be leveraged by several elements, being the composite recycling one of the most important, due to the need to transform the composite waste from production and end of life into new added value materials. For this, the development of efficient composite recycling technologies to not only recover energy during incineration but also high value recycled carbon fibers and semi-products are needed. This project was focused on the recycling of dry carbon fiber scrap, which can proceed from part production by infusion technologies (e.g. RTM) or from pyrolysis of end of life composite part. The approach was to obtain a non-woven mat from the dry fiber scrap, following a mechanical process, which was, then, fully characterized to identify potential applications in aeronautical field. Different approaches of hybridization of the recycled non-woven fabric with virgin fabric were also evaluated.

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It is estimated that the aeronautic industry in the European Union produces annually around 10 tn of uncured prepreg scraps, generated mainly from manual and automated lamination processes of composites, and that the treatment cost for these residues is between 3 and 12 € per kilogram.

This work presents a technology for the reuse of the unidirectional prepreg scrap using a machine that allows the manufacturing companies, mainly form aeronautic sector, the reuse and valorisation of the leftovers of PREPREG in the workshop, involving a reduction in the economic and environmental impact.

The developed solution consists in a machine able to perform the needed processes to reuse the prepreg scrap leftovers in an automatic and efficient way, maintaining the quality and the material properties for the manufacturing of non-critical components. The equipment integrates different technologies that include computer vision to identify the shape of the leftovers and the fibre direction, cutting technology to generate regular rectangular chips aligned with the fibre direction, and a robotic system to pick and place the chips generating an ordered pattern.

The result of the process is a material sheet aiming to control the mechanical properties by using homogeneous chips with controlled fibre orientation following a predefined pattern.