Ab-initio molecular modeling of interfaces in tantalum-carbon system

作者:Balani Kantesh; Bakshi Srinivasa Rao; Mungole Tarang; Agarwal Arvind*
来源:Journal of Applied Physics, 2012, 111(6): 063521.
DOI:10.1063/1.3695368

摘要

Processing of ultrahigh temperature TaC ceramic material with sintering additives of B4C and reinforcement of carbon nanotubes (CNTs) gives rise to possible formation of several interfaces (Ta2C-TaC, TaC-CNT, Ta2C-CNT, TaB2-TaC, and TaB2-CNT) that could influence the resultant properties. Current work focuses on interfaces developed during spark plasma sintering of TaC-system and performing ab initio molecular modeling of the interfaces generated during processing of TaC-B4C and TaC-CNT composites. The energy of the various interfaces has been evaluated and compared with TaC-Ta2C interface. The iso-surface electronic contours are extracted from the calculations eliciting the enhanced stability of TaC-CNT interface by 72.2%. CNTs form stable interfaces with Ta2C and TaB2 phases with a reduction in the energy by 35.8% and 40.4%, respectively. The computed Ta-C-B interfaces are also compared with experimentally observed interfaces in high resolution TEM images.

  • 出版日期2012-3-15