Thermal and electrical properties of spark plasma sintered (Ti,Cr)B2 ceramics |
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| Authors: | Steven M. Smith II Lun Feng William G. Fahrenholtz Gregory E. Hilmas Laura Silvestroni |
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| Affiliation: | 1. Materials Science and Engineering Department, Missouri University of Science and Technology, Rolla, Missouri, USA;2. CNR-ISTEC, Institute of Science and Technology for Ceramic Materials, Faenza, Ravenna, Italy |
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| Abstract: | Thermal and electrical properties were measured for TiB2 ceramics containing varying CrB2 contents up to 33 mol%. The room-temperature thermal diffusivity decreased with increasing Cr content from 0.330 ± 0.003 cm2/s for pure TiB2 to 0.060 ± 0.003 cm2/s for (Ti0.66Cr0.33)B2. The amount of anisotropy in the coefficients of thermal expansion increased with increasing Cr content and the c-axis had the greatest dependence on Cr addition, with an increase of more than 25% in the thermal expansion for 33 mol% CrB2 compared to TiB2, whereas the a-axis only increased by about 8%. The electrical conductivity was the lowest for (Ti0.66Cr0.33)B2 at ∼8.5 × 103 S/cm compared to ∼106.1 × 103 S/cm for nominally pure TiB2. Overall, the addition of CrB2 as a sintering aid for TiB2 was shown to have a significant effect on the thermal and electrical properties of TiB2 for additions as small as 5 mol% CrB2. |
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| Keywords: | electrical conductivity titanium diboride thermal conductivity thermal expansion |
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