What composites really mean – and why the term alone is not enough
The term "composite" is older than many think. It simply refers to the combination of two or more materials that together achieve properties that none of the individual materials possess alone. Reinforced concrete is a composite. A sandwich panel made of aluminum and foam core is also a composite. Therefore, the term initially says little about the actual performance a material brings.
In the industrial context – in aerospace, automotive engineering, and energy technology – the crucial question is not whether a material is a composite, but what type of reinforcement it has and how the matrix system is processed. This is precisely where the difference between thermosetting and thermoplastic composite materials lies – and this difference is fundamental.
Thermosetting composites: high-performance, but with a structural disadvantage
The history of fiber-reinforced plastics begins with thermosets. The reason is obvious: Liquid resin systems – such as epoxy or polyester resin – have a low viscosity and can be easily combined with fibers, introduced into molds, and cured under pressure or in an autoclave. The result is high-strength, precision components that have been used in aerospace and motorsport for decades.
The crucial disadvantage lies in the curing process itself: it is irreversible. Once cured, a thermosetting composite cannot be reshaped, repaired, or meaningfully recycled. The common disposal through incineration yields low energy recovery and can produce toxic emissions. In light of stricter EU regulations on circular economy and increasing pressure on OEMs to demonstrate end-of-life concepts, this disadvantage is increasingly becoming an economic risk – not just an ecological problem.
Thermoplastic Composites: the path to recyclable high-performance materials
The development of thermoplastic composite materials was technically more demanding. Thermoplastic polymers have a significantly higher viscosity in the molten state than liquid resin systems – this long hindered complete and uniform fiber impregnation. Modern manufacturing processes and the development of high-quality UD tapes (unidirectional tapes) have solved this problem.
A UD tape consists of endlessly aligned fibers – typically carbon or glass fibers – that are fully embedded in a thermoplastic matrix. Common matrix materials range from PA6 and PP for less demanding applications to high-performance polymers like PEEK, PEKK, or PAEK for extreme temperature and media resistance. These tapes can be slit into various widths and processed into complex structures in tape laying processes or winding methods – with deliberately adjustable fiber orientation depending on the load case.
What "endlessly fiber-reinforced" specifically means – and why it is crucial
Direct answer: Continuous fiber reinforced thermoplastics (CFR-TP) are composite materials in which continuous fibers – uninterrupted over the entire component length – are embedded in a thermoplastic matrix. Unlike short fiber or long fiber reinforced systems, continuous fibers allow for the full utilization of the mechanical fiber properties. The result: specific stiffnesses and strengths that compete with metals – at a fraction of the weight.
This difference is significant in practice. Short fiber reinforced injection molded parts typically achieve only 20–40% of the theoretical fiber strength. Continuous fiber reinforced laminates or wound bodies, on the other hand, utilize the fiber strength almost completely – provided that the fiber orientation is aligned with the load path. This is precisely what enables the processing of UD tape in tape laying or winding processes: Each layer can be laid down at a defined angle to specifically accommodate tensile, compressive, torsional, or bending loads.
Thermoplastics in the circular economy: no greenwashing, but material reality
A central advantage of thermoplastic matrices is their recyclability. Since the curing process is reversible – thermoplastic polymers soften with heat and can be reshaped – CFR-TP components can be melted, granulated, and reused as secondary material at the end of their life cycle. Manufacturing waste such as tape trimmings can be recycled internally, which increases material efficiency in the production process.
This property is not only ecologically relevant: In light of the EU Ecodesign Directive, the Corporate Sustainability Reporting Standard (CSRS), and the end-of-life requirements in the aviation and automotive industries, recyclability is increasingly becoming a market access condition. CFR-TP materials meet this requirement structurally – not through downstream processing, but through the material property itself.
Market Development: CFR-TP on a Growth Path
The global market for continuous fiber-reinforced thermoplastics is growing significantly. Current market data estimates the CFR-TP market at around 9.1 billion USD (2024) – with a projected annual growth rate (CAGR) of about 14% until 2032. Key drivers include the demand for lightweight structures in aerospace, the trend towards electric drivetrains in automotive manufacturing, and applications in energy technology – from rotor shafts to hydrogen tanks to structural pressure pipes.
Conclusion: The material alone does not decide – the processing does too
CFR-TP materials offer a compelling performance profile: high specific strength and stiffness, recyclability, no storage time, reparability, and suitability for automated manufacturing processes. However, the potential of these materials is only fully realized when the process and material are aligned.
At Alformet, we focus on Laser-Assisted Thermoplastic Winding (LATW) – an automated in-situ consolidation process that operates without an autoclave and directly transfers the advantages of thermoplastic UD tapes into series-compatible pipes and profiles. If you would like to learn more about how CFR-TP materials can be used in your application – please contact us.