News Coatings Technologies

PFAS-free seals enable use of water-based lubricants

Researchers at Fraunhofer have developed an innovative sealing system that eliminates the use of PFAS and supports water-based lubrication. The combination of diamond-like carbon coatings and laser-based microstructuring offers a sustainable alternative for demanding industrial applications.

PFAS
The combination of PFAS-free coating and laser-based microstructuring (right) enables the use of water-based lubricants. Source: Fraunhofer ILT

In the pureWaterSeal project, scientists at the Fraunhofer Institutes for Laser Technology ILT and for Mechanics of Materials IWM have developed environmentally friendly sealing elements that function entirely without per- and polyfluorinated alkyl substances (PFAS) and are compatible with water-based lubricants. The new solution addresses two major industrial challenges: reducing persistent pollutants and replacing petroleum-based lubricants.

Conventional sealing systems often rely on PFAS to increase durability and chemical resistance, while mineral oil-based lubricants pose environmental risks due to potential soil and groundwater contamination. The new development avoids both categories of critical substances while maintaining high performance in applications such as wind turbines, ship propellers and industrial pumps.

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DLC coatings and laser microstructures for robust sealing

The key innovation lies in a diamond-like carbon (DLC) coating tailored to PFAS-free polymer components, developed at Fraunhofer IWM. Combined with localised laser microstructuring by the ILT team, the system reduces mechanical stress, improves coating adhesion and enhances wear and friction performance.

This approach significantly extends the service life of seals and enables, for the first time, the use of water-based lubricants in dynamic applications. The result is a sealing system that minimises environmental impact without compromising technical functionality.

Towards industrial-scale implementation

First prototypes have already been deployed in geothermal pump systems. The next steps include scaling the technology for large-scale use and preparing for industrial series production. Fraunhofer researchers are also working to tailor the system to different customer requirements and load scenarios. A dedicated spin-off company is currently in planning to support commercialisation.

Source: Fraunhofer ILT / Fraunhofer IWM, 2025