Tiny air bubbles can determine how reliable, durable, and sustainable carbon- and glass-fiber-reinforced plastics are – materials used primarily as lightweight components in aircraft manufacturing. Dr. Benedikt Neitzel, a senior research scientist at Technische Universität Ilmenau and managing director of the research association “Materials from Sustainable Raw Materials,” has investigated how such voids can be avoided during manufacturing. He was awarded the 2026 Peter Dornier Foundation Prize for his dissertation and the process control system he developed.
Fiber-reinforced composites are true masters of lightweight construction: They are strong yet significantly lighter than many conventional materials. That is why they are used in the aerospace industry, among other fields. To ensure they can deliver their unique properties, their fine fibers must be as completely and evenly impregnated with synthetic resin as possible during manufacturing and bonded together.
However, this is precisely what poses a particular challenge: In a process known as resin transfer molding (RTM), liquid resin is pressed into a mold containing a dry fiber mat. In this process, the resin must flow through a dense network of tiny gaps. If it does not flow evenly throughout, air can become trapped. This results in voids – barely visible to the naked eye, but with potentially significant consequences.
Because it is not yet possible to predict exactly how much such voids weaken a component, designers must factor in potential manufacturing defects. As a result, they often design components with additional safety margins – making them heavier than necessary. If a component contains too many voids, it may no longer meet quality requirements and must be rejected. This can be particularly costly for high-quality carbon components.
Void content in fiber-reinforced composites reduced by up to 87.5 percent
To save resources and reduce costly scrap in the future, Benedikt Neitzel investigated the permeability of fiber fabric – that is, how quickly and uniformly resin flows through different textile fiber structures – in his dissertation at Plastics Technology Group at TU Ilmenau under the supervision of Prof. Florian Puch.
Based on his research, the Ilmenau-based scientist developed a method that allows for more accurate calculation of resin flow and thus better prediction of void formation. In addition, he developed an automated process control system that can specifically influence the manufacturing process. In experiments, this made it possible to reduce the porosity of test specimens by up to 87.5 percent.
“Especially in aviation, every kilogram saved matters,” says Neitzel:
Lighter aircraft require less energy and can therefore contribute to lower resource consumption and reduced emissions in the long term.
However, more precise production could also help other sectors – such as mechanical and automotive engineering or medical technology – to fully leverage the power of fiber-reinforced composites, avoid scrap, and make better use of available raw materials. According to Neitzel, this is particularly interesting for industry:
My method can be applied without the need for complex additional measurements. This would allow companies to directly incorporate these findings into their manufacturing processes.
Award for Early-Career Researchers
For this work, Neitzel received the Peter Dornier Foundation Award in mid-July 2026. The award ceremony took place at DORNIER GmbH in Lindau on Lake Constance. The prize, which has been awarded since 2021, honors outstanding work by young researchers in the fields of textile, film, and fiber composite technology, as well as aerospace, and is endowed with 5,000 euros.
In 2026, the prize was awarded not only to Neitzel but also to Johanna Buschmann of the German Aerospace Center (DLR). In her master’s thesis, she examined the damage tolerance of three-dimensionally woven fiber-reinforced composite structures.
Original publication
Neitzel, Benedikt: Analyse der Permeabilität textiler Halbzeuge zur Porenminimierung im RTM-Verfahren. Ilmenau, 2025.
Contact
Dr. Benedikt Neitzel
Senior Research Scientist Plastics Technology Group