Chapter 45. Synthesis and Characterisation of TiB2 Whiskers

  1. Todd Jessen and
  2. Ersan Ustundag
  1. Mats Carlsson and
  2. Mats Johnsson

Published Online: 28 MAR 2008

DOI: 10.1002/9780470294635.ch45

24th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures: B: Ceramic Engineering and Science Proceedings, Volume 21, Issue 4

24th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures: B: Ceramic Engineering and Science Proceedings, Volume 21, Issue 4

How to Cite

Carlsson, M. and Johnsson, M. (2000) Synthesis and Characterisation of TiB2 Whiskers, in 24th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures: B: Ceramic Engineering and Science Proceedings, Volume 21, Issue 4 (eds T. Jessen and E. Ustundag), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470294635.ch45

Author Information

  1. Department of Inorganic Chemistry, Stockholm University, S-106 91 Stockholm. Sweden

Publication History

  1. Published Online: 28 MAR 2008
  2. Published Print: 1 JAN 2000

ISBN Information

Print ISBN: 9780470375693

Online ISBN: 9780470294635

SEARCH

Keywords:

  • vapour liquid solid (VLS);
  • oxochloride species;
  • liquid metal catalyst;
  • amorphous carbon;
  • carbonitride phases

Summary

Whiskers of TiB2 have been synthesised via a carbotheimal vapour-liquid- solid (VLS) growth mechanism. In this VLS mechanism Ti and B in the form of gaseous chloride and oxochloride species are transported to a liquid-metal catalyst droplet that becomes supersaturated, resulting in the precipitation of TiB2 as whiskers. The reaction terminates when the levels of reaction gases near the catalyst droplets have dropped below a certain limit. The synthesis was tested and optimised in the temperature region 1100–1800°C in argon. TiO2 was used as precursor material for titanium, and both B2O3 and Na2B4O7 were tested as sources of boron. Amorphous carbon was added to reduce the oxides. NaCl was used as Cl source for the gas-phase transportation. As metal catalysts Ni, Fe, Co, and Cu were evaluated. The best result was obtained with a mixture of TiO2: B2O3 : C : NaCl : Ni in the molar ratios 1 : 1 : 6 : 0.25 : 0.1, at 1500°C. The obtained TiB2. whiskers are −1 μm in diameter and −20 μm in length.