Dynamic magnetic data storage on thermal spray coatings

• Applicants: Professor Dr.-Ing. Kai Möhwald; Professor Dr.-Ing. Marc Christopher Wurz
• Subject Area: Coating and Surface Technology
• Term: since 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 326244920

The overarching goal of this research project is the further development and research of magnetic thermal spray coatings for data storage. In the context of Industry 4.0 and the associated digitalization of production, there is more demand than ever for suitable data storage on components in order to be able to automatically record and process products. The advantages of the spray layers, which result from their resistance to the harsh environmental conditions of the components, make them a promising alternative compared to other solutions for dynamic data storage such as the RFID chip already available on the market.This area of application results in the requirement for a high stability of the written data against external influences such as temperature or interference fields. These requirements can be achieved mainly by the choice of materials and a magnetic anisotropy of the sprayed coatings. In a previous research project (DFG project number 326244920), the basic suitability of the applied WC-Co coatings with regard to their magnetic characteristics and thermal stability was demonstrated. Now, further hard magnetic materials (Fe2O3, FeCr13) are to be produced as spray coatings and investigated in the following. The suitable materials will be included in the further experimental program.The influence of the spraying process on the formation of the magnetic material properties in the applied layer is to be discussed with the aim of being able to change and optimise them in a targeted manner. For this purpose, the relevant process parameters will be varied on the basis of a design of experiment (DOE) and their influence on the formation of the coating will be analysed. The characterization of the produced samples is done by structural and magnetic analysis methods. In order to be able to determine the influence of magnetic field assisted deposition on the microstructure formation, the process chamber in which the spray coatings are produced is also extended by an electromagnet. This includes its simulation supported design and manufacture. In order to ensure optimum writing and reading of data on the thermally sprayed layers, a memory head is also being developed, which will be designed for the previously optimized layer system. The aim is to analyse the achievable data stability and density. In a further work package at the end of this research project, a thermally sprayed layer system that can be written perpendicularly will be developed. This requires an additional soft magnetic layer below the hard magnetic recording medium.

• DFG Programme: Research Grants