A super-hard high entropy boride containing Hf, Mo, Ti, V, and W

Suzana Filipovic, Nina Obradovic, Greg E. Hilmas, William G. Fahrenholtz, Donald W. Brenner, Jon Paul Maria, Douglas E. Wolfe, Eva Zurek, Xiomara Campilongo, Stefano Curtarolo

Research output: Contribution to journalArticlepeer-review


Super-hard (Hf,Mo,Ti,V,W)B2 was synthesized by boro-carbothermal reduction and densified by spark plasma sintering. This composition was produced for the first time as a single-phase ceramic in the present research. The optimized ceramic had a single hexagonal AlB2-type crystalline phase with a grain size of 3.8 µm and homogeneous distribution of the constituent metals. The Vickers hardness exhibited the indentation size effect, increasing from 27 GPa at a load of 9.8 N to as high as 66 GPa at a load of 0.49 N. This is the highest hardness reported to date for high entropy boride ceramics.

Original languageEnglish (US)
Pages (from-to)4430-4435
Number of pages6
JournalJournal of the American Ceramic Society
Issue number7
StatePublished - Jul 2024

All Science Journal Classification (ASJC) codes

  • Ceramics and Composites
  • Materials Chemistry

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