“Composite can compete with aluminium”, Frédéric Sicard, JLR

The Sustainably Optimised Composite Automotive (Soca) project, developed by JLR, aims to decarbonise the manufacture of composite components for automotive applications. By combining recycled carbon fibre and custom manufacturing technology, it initially focuses on carbon fibre parts for low-volume automotive application. The main challenge is to reduce the carbon footprint of these parts while maintaining their performance and lightness. Here are the details of this project, which won a JEC Innovation Award in the Automotive and Road Transport Parts category.

JEC Composites Magazine: Can you describe the Soca project?

Frédéric Sicard: The Soca project contributes to JLR’s Reimagine strategy aimed at achieving carbon net zero across our supply chain, products, and operations by 2039, with all brands offering pure electric options by 2030. With Battery Electric Vehicles, batteries add weight, so we need to develop lightweight innovative alternatives combining sustainability and compliance with the category B driving licence 3.5 tonnes limit.

Soca is based on our previous Tucana lightweight automotive structure design and enables a 55% reduction of its environmental footprint. It also demonstrates that composites can compete with aluminium, including in terms of CO2 emissions. However, today 98% of JLR emissions fall into scope 3 with a major part due to tailpipe emission. Materials production comes second but will become the largest contributor in 2036 (no tailpipe). So, if we have to use carbon fibre to replace aluminium, but if carbon fibre has higher emissions to manufacture than aluminium, it makes no sense. Hence our decision to focus on high-performance recycled fibre products.

To save time and to be able to propose a prototype demonstrator within a year, we started from a previous project, Tucana, whose design we used. In this previous project, we used a lot of virgin fibres to deliver a 30% lighter structure, which substantially reduced emissions during the use phase, but unfortunately these emissions increased during the materials manufacturing phase. Soca has enabled us to remedy this.

What applications are you recommending it for?

F.S.: Most of JLR’s carbon parts are for our ‘Special Vehicle Operations’ division, with limited series of vehicles that do not exceed 5,000 vehicles per year. Some vehicle series take personalisation as far as the smallest details, with bonnets, rims, interior and exterior finishers in carbon, for example. Today, this type of parts is manufactured with virgin carbon fibre conventionally used by the automotive suppliers (T700, T300 for example).

Usual material made from recycled carbon fibres are lighter and less expensive, but generally less effective mechanically and more difficult to process compared to those from virgin fibre. We have therefore developed a demonstrator using the Tucana project design, recycled carbon fibres fabrics (V-Carbon, BlackFabric) and unidirectional tapes (Lineat), and Icomat’s RTS technology. Achieving the required level of quality from the original Tucana design is impossible with conventional AFP technology because of the tight radii of curvature of our design. Icomat RTS technology enables the desired level of curvature and has obtained similar results with Lineat’s tapes.

We are currently looking into technologies capable of aligning recycled short fibres. In Soca, with the support of Far-UK, we identified a number of companies working in this field, including Lineat and V-Carbon in the UK and Black Fabric in Spain. They use three different technologies offering different types of woven fabrics and products. The principle remains the same as they realign and refabricate a continuous roving or a unidirectional tape from discontinuous fibre achieving between 50 and 90% of the mechanical properties of a virgin fibre, but with approximately 10% of the CO2. And that’s what allows us to reduce the footprint of the prototype assembled by CCP-Gransden. In this way, we can create parts that are as light as aluminium, with a lower global warming potential (GWP), but which are still a little more expensive because the supply chain is still in its infancy.

How can the price of these parts be reduced?

F.S.: The cost is higher at the moment, but it depends on volumes. By demonstrating the feasibility of our project, the aim is to highlight the producers of high-performance recycled carbon fibre products so that more customers can work with them and ultimately creating a higher demand. The quantities will then be available when we will need them on a larger scale. We now have ready-to-use materials, so we need to work with our suppliers to validate their integration in future products.

What are the next steps to ensure the conclusions of the Soca project can be implemented on an industrial scale?

F.S.: To begin with, we will introduce the Soca learnings where we currently use carbon fibre, in Special Vehicle Operations (SVO) range, with the goal to reduce the CO2 footprint. Longer term, we will need to work collaboratively with the supply-chain to achieve the required scale-up, i.e. the volumes we need to push these technologies into large volume application outside of SVO.

We also have an interest in working with producers of virgin carbon fibre to optimise their processes and reduce their impact, because there are still applications such as wheels for which we do not yet know whether we will be able to substitute virgin fibre because of the mechanical constraints. We can also envisage combining virgin and recycled fibre to achieve the required aesthetic or performance.

Have you already carried out tests using bio-based materials?

F.S.: In Soca, we have in fact already used biobased epoxy resins, which we have been able to test. We’ve also investigated bamboo fibre from Cobratex and flax fibre from SHD Composites. We have moulded these materials, characterised them mechanically and integrated them into our models so that we can extrapolate them using data from our demonstrator, which will be on display at the JEC show.

Natural fibres are better from a CO2 point of view, but with lower mechanical properties. So, a part with the same level of performance is therefore likely to be thicker, heavier, and in some case more expensive, which don’t position them as a natural contender for direct replacement of virgin carbon fibre in our opinion. Obviously, there are other applications where the use of this type of material makes sense.