skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: {open_quotes}Exchange-spring{close_quotes} Nd{endash}Fe{endash}B alloys: Investigations into reversal mechanisms and their temperature dependence

Abstract

In order to investigate factors affecting coercivity a series of two-phase Nd{sub 2}Fe{sub 14}B-based nanocomposite alloys with different excess iron concentrations were produced by melt-spinning methods. The constituent grain size was estimated by diffraction methods to be in the range of 150{endash}500 {Angstrom}, and room-temperature demagnetization curves verify that the alloys studied exhibit a modest remanence enhancement. Isothermal remanence magnetization (IRM) and dc demagnetization (DCD) measurements performed at temperatures in the range 275K{le}T{le}350K illustrate that the coercivity and irreversible magnetization develop in a bimodal, incoherent manner from a demagnetized state but upon demagnetization from a saturated state the system evinces collective, exchange-coupled behavior as illustrated by the reversible magnetization M{sub rev}. The temperature dependencies and values of the irreversible susceptibility {chi}{sub irr} (DCD) suggest that a moderating phase with a magnetic anisotropy intermediate to the two constituent main phases may be present in the alloys. {copyright} {ital 1997 American Institute of Physics.}

Authors:
;  [1];  [2]
  1. Department of Applied Science, Brookhaven National Laboratory, Upton, New York 11973-5000 (United States)
  2. Magnequench International (MQI), Incorporated, 6435 Scatterfield Road, Anderson, Indiana 46013 (United States)
Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States)
OSTI Identifier:
496478
Report Number(s):
CONF-961141-
Journal ID: JAPIAU; ISSN 0021-8979; TRN: 97:016175
DOE Contract Number:  
AC02-76CH00016
Resource Type:
Journal Article
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 81; Journal Issue: 8; Conference: 41. annual conference on magnetism and magnetic materials, Atlanta, GA (United States), 12-15 Nov 1996; Other Information: PBD: Apr 1997
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; NEODYMIUM ALLOYS; MAGNETIZATION; IRON ALLOYS; BORON ALLOYS; PERMANENT MAGNETS; X-RAY DIFFRACTION; TEMPERATURE DEPENDENCE; COERCIVE FORCE; MAGNETIC SUSCEPTIBILITY; TEMPERATURE RANGE 0273-0400 K

Citation Formats

Lewis, L H, Welch, D O, and Panchanathan, V. {open_quotes}Exchange-spring{close_quotes} Nd{endash}Fe{endash}B alloys: Investigations into reversal mechanisms and their temperature dependence. United States: N. p., 1997. Web. doi:10.1063/1.364789.
Lewis, L H, Welch, D O, & Panchanathan, V. {open_quotes}Exchange-spring{close_quotes} Nd{endash}Fe{endash}B alloys: Investigations into reversal mechanisms and their temperature dependence. United States. https://doi.org/10.1063/1.364789
Lewis, L H, Welch, D O, and Panchanathan, V. 1997. "{open_quotes}Exchange-spring{close_quotes} Nd{endash}Fe{endash}B alloys: Investigations into reversal mechanisms and their temperature dependence". United States. https://doi.org/10.1063/1.364789.
@article{osti_496478,
title = {{open_quotes}Exchange-spring{close_quotes} Nd{endash}Fe{endash}B alloys: Investigations into reversal mechanisms and their temperature dependence},
author = {Lewis, L H and Welch, D O and Panchanathan, V},
abstractNote = {In order to investigate factors affecting coercivity a series of two-phase Nd{sub 2}Fe{sub 14}B-based nanocomposite alloys with different excess iron concentrations were produced by melt-spinning methods. The constituent grain size was estimated by diffraction methods to be in the range of 150{endash}500 {Angstrom}, and room-temperature demagnetization curves verify that the alloys studied exhibit a modest remanence enhancement. Isothermal remanence magnetization (IRM) and dc demagnetization (DCD) measurements performed at temperatures in the range 275K{le}T{le}350K illustrate that the coercivity and irreversible magnetization develop in a bimodal, incoherent manner from a demagnetized state but upon demagnetization from a saturated state the system evinces collective, exchange-coupled behavior as illustrated by the reversible magnetization M{sub rev}. The temperature dependencies and values of the irreversible susceptibility {chi}{sub irr} (DCD) suggest that a moderating phase with a magnetic anisotropy intermediate to the two constituent main phases may be present in the alloys. {copyright} {ital 1997 American Institute of Physics.}},
doi = {10.1063/1.364789},
url = {https://www.osti.gov/biblio/496478}, journal = {Journal of Applied Physics},
number = 8,
volume = 81,
place = {United States},
year = {Tue Apr 01 00:00:00 EST 1997},
month = {Tue Apr 01 00:00:00 EST 1997}
}