TARGETING EARTH ABUNDANT SUPERHARD MATERIALS WITH BIG DATA

A majority of the known inorganic superhard materials contain expensive 4d or 5d transition metals, such as Ru, Rh, Os, Re, Ir, and boron. Although these materials show excellent mechanical properties, their widespread application is currently limited due to extreme conditions required to prepare the materials as well as the cost of the raw starting materials. In fact, specialized synthetic equipment is required because the starting materials are refractory metals with melting points often >2000°C. Thus, for any wide-scale application of superhard materials, the synthetic conditions and prohibitive cost need to be addressed.

In the Brgoch group, we are developing new superhard materials that require less challenging processing conditions and contain a larger percentage of earth-abundant starting materials. Specifically, our research is focusing on:

• Analyzing the mechanical properties of known compounds using techniques borrowed from our colleagues in data mining to identify correlations. First-principles (DFT) calculations will be employed to determine additional metrics that should correlate with hardness, e.g., total bond strength. This will allow us to develop a set of “design rules” that will direct our experimental preparation.

• New materials will be prepared using an innovative microwave-assisted preparation route. This method allows for rapid screening of new compositions utilizing a fraction of the power necessary for arc-melting. All of the materials will be characterized using micro-indentation, X-ray diffraction, solid-state NMR, and powder neutron diffraction