Model-based development of a hybrid process for surface finishing using in-line coating and incremental recrystallization rolling

• Applicant: Professor Dr.-Ing. Sebastian Härtel
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 539450784

The increased use of recycled paper and cardboard is becoming increasingly important, particularly in the packaging, transport and logistics sectors, in order to reduce carbon emissions and achieve decarbonization targets. Thanks to advances in paper manufacturing, paper can now be recycled up to 25 times, which is particularly remarkable in the packaging industry. However, this increased recycling requires chemical additives during production to improve recyclability, which in turn places higher demands on the durability and resistance of paper rolls to wear and corrosion. Optimum thermal conductivity of the coating and a high heat transfer coefficient between coating and substrate are advantageous in this process. Material selection, coating process and post-processing are the central stages in the production chain for coated roll tools. A holistic process approach and continuous further development of the entire production chain are necessary in order to meet the increasing technical requirements for rolling tools and at the same time ensure cost-effectiveness. In order to improve the material and energy efficiency within the production chain of coated components, in particular rollers, and to increase the wear and corrosion resistance of these coatings, a new sustainable hybrid process is being developed as part of the "HeatCoatRoll" initiative. The overall aim of the "HeatCoatRoll" project is to develop a hybrid process that combines thermal spraying or laser cladding coating process with incremental recrystallization rolling. This innovation promises to improve the efficiency of current paper roll coating processes, potentially increasing material, energy and cost efficiency by up to 30%. In addition, it is expected that this advance could extend the life of the coated rolls by at least 30%. The knowledge gained should make it possible to transfer the process understanding developed to date as part of the DFG research project "HeatWeldForming" from welding to thermal spraying and laser cladding coating processes and to increase the technology maturity level achieved from TRL 4 to TRL 7. The scientific basis for the successful fulfillment of the overall objective and the design of the hybrid processes is the development of a basic understanding of process-structure-property correlations. The linking of the developed simulation-based process design with data from extensive experimental structure and property investigations is the central object of the research. This basic understanding will be used to develop a digital prediction model for targeted layer modeling and design in the final phase of the project and thus prepare the basis for the transfer to a broad industrial application of the hybrid process, which goes far beyond the coating of paper rolls addressed here.

• DFG Programme: Research Grants (Transfer Project)
• Application Partner: ECOROLL AG; Oerlikon Metco AG; Voith Austria GmbH
• Cooperation Partner: Professorin Dr.-Ing. Martina Zimmermann