Synthesis, structure and deformation behaviour of superhard and damage tolerant PVD thin films based on nano structured nitrides of high-entropy multicomponent alloys

• Applicants: Professor Dr.-Ing. Christoph Leyens; Professorin Dr.-Ing. Martina Zimmermann
• Subject Area: Coating and Surface Technology ; Mechanical Properties of Metallic Materials and their Microstructural Origins
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 443649646

Despite a great industrial demand for superhard (hardness > 40 GPa) yet tough thin films with high thermal stability (T > 1000°C) such films can currently not be synthesized. On the one hand side thin films which are typically used for the protection of tools and components only partly fulfill these criteria. On the other hand the deformation and damage behavior determining the mechanical properties of these thin films is not fully understood yet. Therefore the aim of the project proposal is the synthesis of new superhard yet tough thin film systems on the basis of high entropy alloy nitrides, the exploration of their mechanical properties and the determination of the underlying deformation and damage mechanisms. By combining the utilization of HEA nitrides with the design concepts of nanostructured thin films it is assumed that for the first time the three before mentioned criteria can be simultaneously achieved.To establish fundamental principles for the synthesis of new superhard yet tough thin film systems based on HEA nitrides the intended project combines the comprehensive expertise on the development of complex thin films and their resulting mechanical properties (Leyens) with the characterization of the mechanical behavior and damage mechanisms as well as their interrelationships (Zimmermann). In the intended project a comprehensive understanding of the correlation between structure and mechanical properties of the newly developed thin film systems will be established. The obtained results will be generalized and transferred to classical hard nitride systems with fcc structure. From a methodological perspective, techniques for quasi high throughput evalution of the mechanical properties for thin films will be developed and evaluated.

• DFG Programme: Research Grants