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Nanotube growth during annealing of mechanically milled Boron

journal contribution
posted on 01.01.2003, 00:00 authored by J D Fitz Gerald, Ying (Ian) ChenYing (Ian) Chen, M J Conway
Boron powder, finely ground in a tungsten carbide ball mill in an ammonia atmosphere, has been annealed at 1200°C in flowing nitrogen to produce small quantities of cylindrical BN nanotubes, both as isolated individuals and grouped into ropes. Thick-walled conical BN tubes are abundant in specimens annealed for longer times, and their growth was catalysed once WC debris was converted into W metal particles. Some catalytic effect of small W nanoparticles could be necessary for nanotube formation, though no tip particles have been imaged here. Given the low temperature of mechanical milling and annealing. BN growth must involve surface diffusion and solid-state reconfiguration. It could be possible to engineer desirable physical and chemical properties by exploiting the variation in cylindrical versus conical BN structures as a function of annealing time.

History

Journal

Applied physics A: materials science and processing

Volume

76

Issue

1

Pagination

107 - 110

Publisher

Springer

Location

Heidelberg, Germany

ISSN

0947-8396

eISSN

1432-0630

Language

eng

Publication classification

C1.1 Refereed article in a scholarly journal

Copyright notice

2002, Springer