High-throughput material characterization using laser deposition additive manufacturing combined with high-flux in situ X-Ray analysis enhanced by further instrumentation

• Subject Area: Metallurgical, Thermal and Thermomechanical Treatment of Materials ; Mechanical Properties of Metallic Materials and their Microstructural Origins
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 434506338

Material screening in bulk is still a challenge for researchers in materials science and engineering and production technology. Traditionally, for metal alloy design small ingots are cast, heattreated and characterized by conventional techniques, such as optical microscopy and mechanical testing. In parallel simulations, e.g. based on thermodynamic considerations, assist alloy design. In plastics technology the process chain for design of novel materials is compounding, granulating and injection molding followed by subsequent conventional analysis. Following these established procedures, all experimental steps are highly time consuming. Furthermore, characteristics for materials processed by additive manufacturing (AM) can hardly be established following these approaches, since microstructures and related properties of AM materials, at least for metals, are far from equilibrium.Thus, novel facilities allowing for rapid alloy screening in bulk have to be realized, taking into account the relevant material conditions (AM). Laser deposition, combined with in situ X-Ray analysis using a high-flux XRD source will allow for tackling prevailing gaps in this field. In principle, the proposed system is inspired by two state-of-the-art approaches used for alloy screening in the field of metals: deposition of thin-film materials libraries followed by high-throughput characterization, and in situ analysis of microstructure evolution by means of synchrotron radiation. It is important to note that both approaches have inherent drawbacks. Thin films are not able to capture microstructures of rapidly solidified (AM) materials and properties of thin films can differ from those of their bulk counterparts. In situ synchrotron analysis is a very powerful tool; however, beam time is strictly limited.The proposed system allows overcoming these issues and, thus, enables high-throughput characterization of complex AM bulk materials libraries at high availability. Laser deposition using different wires and powders will allow for manufacturing bulk samples, where chemical composition can vary sample by sample and/or layer by layer, respectively. Thereby, monolithic materials as well as composite materials and materials composites can be considered using metals, ceramics and polymers as basis (elementary materials and/or pre-alloys). In situ X-Ray diffraction and X-Ray radiography will allow for analysis of melt pool dynamics and evolution of internal defects as well as in-depth characterization of crystalline phases in real-time. Furthermore, additional instrumentation, which will be further detailed in the proposal, will assist screening of microstructures and related properties in real time. The principal investigators will cover all relevant aspects (from laser-based processing to final property evaluation including measurement and control, data analysis and application in numerous fields) for realization and efficient use of the proposed system.

• DFG Programme: Major Instrumentation Initiatives
• Major Instrumentation: System for Laser Deposition
• Instrumentation Group: 4050 Meßelektronik und Zubehör für Röntgengeräte
• Applicant Institution: Universität Kassel
• Leader: Professor Dr.-Ing. Thomas Niendorf
• Co-Investigators: Professor Dr.-Ing. Stefan Böhm; Professor Dr.-Ing. Hans-Peter Heim