Screw Dislocation Assisted Spontaneous Growth of HfB2 Tubes and Rods. Issue 7 (23rd April 2015)

• Record Type: Journal Article
• Authors: Venugopal, Saranya; Jayaseelan, Daniel Doni; Paul, Anish; Vaidhyanathan, Bala; Binner, Jon G. P.; Brown, Peter M.; Fahrenholtz, W.
• Is Part Of: Journal of the American Ceramic Society. Volume 98:Issue 7(2015)
• Page Start: 2060
• Page End: 2064
• Publication Date: 2015-04-23
• Subjects: Ceramics -- Periodicals; 620.1405
• DOI: 10.1111/jace.13615
• Languages: English
• ISSNs: 0002-7820

Abstract

<abstract abstract-type="main" id="jace13615-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p>The mechanism of anisotropic growth of HfB₂ rods has been discussed in this study. HfB₂ powder has been synthesized via a sol–gel‐based route using phenolic resin, hafnium chloride, and boric acid as the source of carbon, hafnium, and boron respectively, though a small number of comparative experiments involved amorphous boron as the boron source. The effects of calcination dwell time and Hf:C and Hf:B molar ratio on the purity and morphology of the final powder have been studied and the mechanism of anisotropic growth of HfB₂ has been investigated. It is hypothesized that imperfect oriented attachment of finer HfB₂ particles results in screw dislocations in the coarser particles. The screw dislocation facilitates dislocation‐driven growth of particles into anisotropic HfB₂ rods.</p> </abstract>