Discovery and optimization of new materials using combinatorial materials science
Alfred Ludwig, Ruhr-Universität Bochum, Bochum, Germany
The directed and efficient discovery and optimization of materials is a key challenge in materials science. New materials for actuation in MEMS as well as new materials for the sustainable production/storage/conversion of energy carriers are necessary to improve existing and enable future products. By implementing and optimizing the combinatorial materials science approach in our group during the last ten years, we are trying to contribute to this development. It comprises the fabrication and processing of thin film materials libraries by several combinatorial sputter deposition processes (40 elements available) and optional post-deposition treatments (e.g. annealing, thermal oxidation) followed by the high-throughput characterization of the different thin film samples contained in these libraries, and in a last step the up-scaling of findings from materials libraries to larger sizes.
Our high-throughput material characterization methods are automated, fast, and mostly non-destructive: examples are EDX and RBS for composition, XRD for crystal structure, temperature-dependent resistance for phase transformation, high-throughput test stands for optical properties and mechanical properties (stress, hardness, elastic modulus). The obtained results for ternary and quaternary systems are visualized in the form of composition-processing-structure-function diagrams, interlinking compositional data with structural and functional properties.
The talk will cover combinatorial exploration of intermetallic systems with regard to identifying unknown phases as well as to explore the compositional ranges of the observed phases. Examples of the combinatorial exploration of intermetallic material systems for shape memory (Ti-Ni-X-Y, Ti-Ta-X) and thermoelectric (Ti-Ni-Sn) applications as well as results on the investigation of ternary subsystems of Ni- and Co-based superalloys (Ni-Al-X, Co-Al-X, Co-Ni-Al, Co-Ti-W, …) will be discussed.