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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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Data-driven discovery of a formation prediction rule on high-entropy ceramics

The interest in high entropy ceramics (HECs) has increased steadily due to their superior properties. However, the prediction of their formation still poses challenges for the discovery of new systems. Here, we discover a rational rule for designing single-phase high entropy metal diborides (HEBs) using data-driven approach. The machine learning (ML) model is trained on data collected via high-throughput experiments (HTEs). K nearest neighbor (KNN) model shows an experimental validation accuracy of 93.75%. By implementing interpretable ML method, we demonstrate that a mismatch of the bonds between boron and transition metals (δ B-TM ) dominates the formation of HEBs. We propose an empirical rule that HEBs favor forming a single phase when δ B-TM < 3.66; otherwise, multiphase. The rule has a high accuracy of 93.33% for new HEBs predictions. In addition, we contribute 165 high quality HEBs data in total, which can promote the development of materials informatics in HEBs. Furthermore, this data-driven strategy can be expanded to accelerate the search for new HECs, paving a pathway to design novel HECs with superior properties rapidly.

36 MATERIALS SCIENCE↗

Materials Data on TmB6 by Materials Project

TmB6 is Calcium hexaboride structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Tm is bonded in a 1-coordinate geometry to twenty-four equivalent B atoms. All Tm–B bond lengths are 3.00 Å. B is bonded in a 1-coordinate geometry to four equivalent Tm and five equivalent B atoms. There is one shorter (1.62 Å) and four longer (1.74 Å) B–B bond length.

36 MATERIALS SCIENCE↗

Materials Data on TmB2 by Materials Project

TmB2 is hexagonal omega structure structured and crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Tm is bonded to twelve equivalent B atoms to form a mixture of face and edge-sharing TmB12 cuboctahedra. All Tm–B bond lengths are 2.66 Å. B is bonded in a 9-coordinate geometry to six equivalent Tm and three equivalent B atoms. All B–B bond lengths are 1.88 Å.

36 MATERIALS SCIENCE↗

Materials Data on TmB12 by Materials Project

TmB12 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Tm is bonded in a 1-coordinate geometry to twenty-four equivalent B atoms. All Tm–B bond lengths are 2.78 Å. B is bonded in a 7-coordinate geometry to two equivalent Tm and five equivalent B atoms. There is one shorter (1.71 Å) and four longer (1.79 Å) B–B bond length.

36 MATERIALS SCIENCE↗