Quantum-mechanic design and evaluation of precious metal coatings for the reduction of glass adhesions during an isothermal molding process

• Applicants: Professor Dr.-Ing. Fritz Klocke; Professor Jochen M. Schneider, Ph.D.
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing ; Thermodynamics and Kinetics as well as Properties of Phases and Microstructure of Materials
• Term: from 2016 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 285743263

During the isothermal glass molding process of Precision Glass Molding, coated molding tools are exposed to a dynamic set of stress and frictional loads between glass and coating. As a result, precious metal coatings predominantly applied show characteristic glass adhesions, whose reasons for the formation are currently not understood. Hence, a knowledge-based approach for the reduction of wear phenomena by purposeful adjustment of the coating system is currently not available. The heuristic approaches currently applied are time, material and cost intensive and did not lead to successes regarding the reduction of glass adhesions. However, it is known, that the adjustment of adhesion and top layer of the coating system has a decisive influence on the stability of the coating, and on the standard life time of the molding tools, respectively. The quantum mechanics-based modeling of the interface between coating and polymers provided a promising approach for the assessment of the strength of glass adhesion on different coatings. The aim of the proposed project is therefore the fundamental investigation simulation-based modeling of the reasons for glass adhesions on precious metal coatings under typical process conditions. Within the project, fundamental mechanisms for glass adhesions for a commonly used glass (B270; distributor: Schott) are to be identified by by a quanum-mechanical description of the interactions on an atomic scale. Based on these interaction descriptions, coating composition alternatives are to be predicted. Coating alternatives, i.e. predictions of the model, are to be evaluated experimentally.

• DFG Programme: Research Grants