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Title: Structural and microstructural changes in monoclinic ZrO{sub 2} during the ball-milling with stainless steel assembly

Abstract

High-energy ball-milling of monoclinic ZrO{sub 2} was performed in air using the planetary ball mill with a stainless steel milling assembly. Structural and microstructural changes during the ball-milling were monitored using X-ray powder diffraction, Raman spectroscopy, Moessbauer spectroscopy, field emission scanning electron microscopy and energy dispersive X-ray spectrometry. The results of line broadening analysis indicated a decrease in the crystallite size and an increase in the microstrains with the ball-milling time increased up to {approx}150 min. The results of quantitative phase analysis indicated the presence of a very small amount of tetragonal ZrO{sub 2} phase in this early stage of ball-milling. The onset of m-ZrO{sub 2} {sup {yields}} t-ZrO{sub 2} transition occurred between 10 and 15 h of ball-milling, which resulted in a complete transition after 20 h of ball-milling. Further ball-milling caused a decrease of the t-ZrO{sub 2} lattice parameters followed by a probable transition into c-ZrO{sub 2}. It was concluded that the stabilization of t- and c-ZrO{sub 2} polymorphs at RT can be attributed to the incorporation of aliovalent cations (Fe{sup 2+}, Fe{sup 3+} and Cr{sup 3+}) introduced into the sample due to the wear and oxidation of the milling media.

Authors:
 [1];  [2];  [2]
  1. Ruder Boskovic Institute, P.O. Box 180, HR-10002 Zagreb (Croatia). E-mail: stefanic@irb.hr
  2. Ruder Boskovic Institute, P.O. Box 180, HR-10002 Zagreb (Croatia)
Publication Date:
OSTI Identifier:
20891661
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Research Bulletin; Journal Volume: 41; Journal Issue: 4; Other Information: DOI: 10.1016/j.materresbull.2005.10.006; PII: S0025-5408(05)00386-7; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CHROMIUM IONS; FIELD EMISSION; IRON IONS; LATTICE PARAMETERS; LINE BROADENING; MICROSTRUCTURE; MILLING; MOESSBAUER EFFECT; MONOCLINIC LATTICES; OXIDATION; PHASE STUDIES; RAMAN SPECTROSCOPY; SCANNING ELECTRON MICROSCOPY; STABILIZATION; STAINLESS STEELS; X-RAY DIFFRACTION; X-RAY SPECTROSCOPY; ZIRCONIUM OXIDES

Citation Formats

Stefanic, G., Music, S., and Gajovic, A. Structural and microstructural changes in monoclinic ZrO{sub 2} during the ball-milling with stainless steel assembly. United States: N. p., 2006. Web. doi:10.1016/j.materresbull.2005.10.006.
Stefanic, G., Music, S., & Gajovic, A. Structural and microstructural changes in monoclinic ZrO{sub 2} during the ball-milling with stainless steel assembly. United States. doi:10.1016/j.materresbull.2005.10.006.
Stefanic, G., Music, S., and Gajovic, A. Thu . "Structural and microstructural changes in monoclinic ZrO{sub 2} during the ball-milling with stainless steel assembly". United States. doi:10.1016/j.materresbull.2005.10.006.
@article{osti_20891661,
title = {Structural and microstructural changes in monoclinic ZrO{sub 2} during the ball-milling with stainless steel assembly},
author = {Stefanic, G. and Music, S. and Gajovic, A.},
abstractNote = {High-energy ball-milling of monoclinic ZrO{sub 2} was performed in air using the planetary ball mill with a stainless steel milling assembly. Structural and microstructural changes during the ball-milling were monitored using X-ray powder diffraction, Raman spectroscopy, Moessbauer spectroscopy, field emission scanning electron microscopy and energy dispersive X-ray spectrometry. The results of line broadening analysis indicated a decrease in the crystallite size and an increase in the microstrains with the ball-milling time increased up to {approx}150 min. The results of quantitative phase analysis indicated the presence of a very small amount of tetragonal ZrO{sub 2} phase in this early stage of ball-milling. The onset of m-ZrO{sub 2} {sup {yields}} t-ZrO{sub 2} transition occurred between 10 and 15 h of ball-milling, which resulted in a complete transition after 20 h of ball-milling. Further ball-milling caused a decrease of the t-ZrO{sub 2} lattice parameters followed by a probable transition into c-ZrO{sub 2}. It was concluded that the stabilization of t- and c-ZrO{sub 2} polymorphs at RT can be attributed to the incorporation of aliovalent cations (Fe{sup 2+}, Fe{sup 3+} and Cr{sup 3+}) introduced into the sample due to the wear and oxidation of the milling media.},
doi = {10.1016/j.materresbull.2005.10.006},
journal = {Materials Research Bulletin},
number = 4,
volume = 41,
place = {United States},
year = {Thu Apr 13 00:00:00 EDT 2006},
month = {Thu Apr 13 00:00:00 EDT 2006}
}
  • We report the first study of the effect of high-energy mechanical deformation on amorphous iron-based metallic alloys. The structural changes happening in amorphous iron-based materials containing Co or Ni during mechanical deformation show that the structural stability of an amorphous alloy against a thermal and a mechanical process are not related. Therefore, the concept of a high local effective temperature during the milling process cannot be singled out as the only reason for the observed structural transformations.
  • No abstract prepared.
  • The atomic-scale structure of nanocrystalline ZrO{sub 2} obtained by ball milling has been studied using high-energy x-ray diffraction and the atomic pair distribution function technique. The studies show that, upon relatively short milling times, the parent crystalline material, monoclinic ZrO{sub 2}, evolves into a nanocrystalline phase that is locally similar to monoclinic zirconia but shows a cubic-type ordering at nanometer-range distances. The result underlines the importance of local structural distortions in stabilizing the technologically important cubic zirconia at room temperature.
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  • The solid state reactions and the microstructural evolution during high-energy ball milling of Al-Ni powder mixtures in the composition rate 25--75 at.% Al have been investigated. Experimental observations have shown that the microscopic mechanism underlying the alloying process in this system is the diffusion of Ni atoms in the Al-rich layers and that an important role is played by the oxygen contamination. An amorphous Al-rich phase containing a few at.% oxygen and with a Ni content not exceeding approximately 50 at.% has been detected in the equiatomic and Ni-rich samples milled for a few hours. This phase upon further millingmore » transforms to a Ni-rich fcc solid solution thus allowing one to by-pass the nucleation of Al{sub 3}Ni in these samples. The self-sustaining high-temperature synthesis of the AlNi B2 phase has been found to occur over the 40--60 at.% range of Al concentration after about 3 h of milling. The same reaction has been observed in the Differential Scanning Calorimeter if equiatomic samples premilled for about 3 h (unreacted) are heated at a sufficiently high heating rate.« less