“We are transforming coating development from a trial-and-error principle into systematic screening. This allows complex material systems to be investigated in a fraction of the time previously required,” explains Dr. Martin Fenker, Head of the Plasma Surface Technology Department at the fem Research Institute.
At the core of the approach is Combinatorial Magnetron Sputtering (CMS), in which several magnetron sputtering sources are operated simultaneously. The arrangement of the sources creates defined lateral composition gradients on the substrate.
One Coating Sample Includes Multiple Variants
This principle turns a single sample into a material library: numerous different material variants are produced in one process run and can then be systematically analyzed. Properties such as hardness, corrosion behavior, or optical parameters can be assigned along these composition gradients.
Unlike conventional development methods based on iterative approximation, the approach enables structured screening of material systems. Experimental effort for coating deposition is reduced by at least a factor of 10 to 100, while correlations between composition, phase formation, and functional properties become apparent at the same time.
Spatially resolved characterization — for example through CIE Lab color measurements, instrumented hardness testing, or corrosion tests — generates structured datasets. These form the basis for data-driven materials development as well as materials informatics and artificial intelligence methods.
The performance of the process has already been demonstrated in several projects. In the EU-funded “Coloured Gold” project, combinatorial co-sputtering was used to create different color states in metallic coatings. Development cycles for coating deposition were reduced from many years to just a few months.
In the IGF project “Refmags,” the method was transferred to complex metal nitride systems. The researchers showed that mechanical and chemical properties can be adjusted through the magnesium content. At the same time, they identified systematic relationships between composition, microstructure, and material properties.
Development Times for New Coatings Reduced
For industrial users, this translates into a competitive advantage: companies can evaluate material systems more quickly, reduce development risks, and shorten time to market. The approach is particularly relevant for small and medium-sized enterprises. They can use combinatorial coating development as a screening platform to identify promising material systems before transferring them into production-relevant processes, helping to avoid costly misinvestments.
The combinatorial approach is scalable and can be applied across numerous applications — from wear- and corrosion-resistant protective coatings and decorative surfaces to optical and functional coatings as well as applications in the energy and medical technology sectors. For mid-sized industrial companies, the approach provides more efficient access to new materials and shortens the path from concept to industrial application.