Please use this identifier to cite or link to this item: https://doi.org/10.1016/j.intermet.2011.04.006
Title: Atomistic mechanism of cyclic phase transitions in Nd-Fe-B based intermetallics
Authors: Shukla, S.
Banas, A. 
Ramanujan, R.V.
Keywords: A. Nanostructured intermetallics (including preparation methods)
B. Phase transformation (crystallographic aspects kinetics and mechanisms)
C. Mechanical alloying and milling
D. Defects: point defects
F. Spectroscopic methods, various
Issue Date: Aug-2011
Citation: Shukla, S., Banas, A., Ramanujan, R.V. (2011-08). Atomistic mechanism of cyclic phase transitions in Nd-Fe-B based intermetallics. Intermetallics 19 (8) : 1265-1273. ScholarBank@NUS Repository. https://doi.org/10.1016/j.intermet.2011.04.006
Abstract: Mechanical milling induced atomic disorder and the mechanism of the cyclic crystal → amorphous → crystal phase transitions in a Nd 2Fe14B intermetallic - based Nd10Fe 85B5 alloy were investigated. Least square first shell fitting of Extended X-ray Absorption Fine-Structure (EXAFS) data of mechanically milled samples revealed that phase evolution during mechanical milling of Nd10Fe85B5 alloy occurred in two stages as a result of two dynamical effects: milling induced forced atomic mixing and enhanced diffusion due to continuous production of point defects. In the first stage of milling, atomic mixing of Nd and Fe atoms dominated, resulting in extensive chemical and structural disorder in the initially ordered intermetallic, followed by amorphization. The second stage of milling was characterized by a remarkable increase in point defect density. Enhanced diffusion resulted in redistribution of alloy atoms and annihilation of these point defects leading to the precipitation of α-Fe nanocrystals in the amorphous matrix. Thus the time evolution of defect structures formed during mechanical milling and their atomic scale interactions led to the cyclic phase transitions in the Nd10Fe85B5 alloy. These milling induced changes in atomic order were found to strongly influence magnetic properties. Crystallization of mechanically milled alloy and effect of annealing parameters on magnetic properties was also analyzed. © 2011 Elsevier Ltd. All rights reserved.
Source Title: Intermetallics
URI: http://scholarbank.nus.edu.sg/handle/10635/113009
ISSN: 09669795
DOI: 10.1016/j.intermet.2011.04.006
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.

SCOPUSTM   
Citations

13
checked on May 29, 2020

WEB OF SCIENCETM
Citations

13
checked on May 22, 2020

Page view(s)

82
checked on May 30, 2020

Google ScholarTM

Check

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.