Publication: First principles calculations and synthesis of multi-phase (HfTiWZr)B2 high entropy diboride ceramics: microstructural, mechanical and thermal characterization
Program
KU-Authors
KU Authors
Co-Authors
Kavak, S.
Bayrak, K. G.
Mansoor, M.
Kaba, M.
Ayas, E.
Derin, B.
Öveçoğlu, M.L.
Ağaoğulları, D.
Advisor
Publication Date
Language
English
Type
Journal Title
Journal ISSN
Volume Title
Abstract
First principles calculations were conducted on (HfTiWZr)B2 high entropy diboride (HEB) composition, which indicated a low formation energy and promising mechanical properties. The (HfTiWZr)B2 HEBs were synthesized from the constituent borides and elemental boron powders via high energy ball milling and spark plasma sintering. X-ray diffraction analyses revealed two main phases for the sintered samples: AlB2 structured HEB phase and W-rich secondary phase. To investigate the performance of multi-phase microstructures containing a significant percentage of the HEB phase was focused in this study. The highest microhardness, nanohardness, and lowest wear volume loss were obtained for the 10 h milled and 2050 °C sintered sample as 24.34 ± 1.99 GPa, 32.8 ± 1.9 GPa and 1.41 ± 0.07 × 10−4 mm3, respectively. Thermal conductivity measurements revealed that these multi-phase HEBs have low values varied between 15 and 23 W/mK. Thermal gravimetry measurements showed their mass gains below 2% at 1200 °C. © 2022 Elsevier Ltd
Description
Source:
Journal of the European Ceramic Society
Publisher:
Elsevier B.V.
Keywords:
Subject
Materials science, Ceramics