fulltext.study @t Gmail

Investigation of mechanically stimulated solid phase polymorphic transition of zirconia

Paper ID Volume ID Publish Year Pages File Format Full-Text
44272 46011 2006 7 PDF Available
Title
Investigation of mechanically stimulated solid phase polymorphic transition of zirconia
Abstract

The effect of mechanical treatment of monoclinic zirconia in a high-energy centrifugal planetary ball mill and in a vibrating ball mill, with much less mechanical impact, on its crystallographic characteristics and texture was investigated as a function of the applied mechanical load and the treatment medium. Mechanical treatment in a high-energy planetary ball mill was shown to result in particle desintegration into small crystallites of less than 20 nm in size, accumulation of strains, and fast solid phase transition to metastable nano-structured tetragonal form. The rate of the phase transition depended on the treatment medium. The transition completed during 15 min with dry-powdered ZrO2. The presence of water retarded the phase transition. Mechanical treatment in a vibrating mill resulted in particle desintegration into crystallites of 38–42 nm in size, accumulation of strains, and gradual amorphization of the crystalline structure; however, the transformation to the tetragonal form did not occur. The factors favored the solid phase polymorphic transition of a stable form of ZrO2 into metastable one are discussed. A high-temperature and a high pressure, which are developed in local sites of the solid under pulse mechanical impact of high-energy, provide thermodynamically favorable conditions and kinetic acceleration of the phase transition. The effect of the metastable form of ZrO2 stabilization originates from the small size of the crystallites as a result of particle desintegration.

Keywords
Zirconia; Mechanical activation; Milling; Solid phase transition
First Page Preview
Investigation of mechanically stimulated solid phase polymorphic transition of zirconia
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Applied Catalysis A: General - Volume 298, 10 January 2006, Pages 254–260
Authors
, , , , , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Catalysis
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us