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Title: Evolution of structural and magnetic properties in La xCe 2-xCo 16 Ti for $$0 \leq x \leq 2$$

Abstract

Here we examine the intrinsic magnetic and structural properties of the title alloys, permanent magnet materials based on the abundant rare-earth elements lanthanum and cerium, since these properties (T C, M sH a(K 1, K 2)) will set the upper limits on the quality of permanent magnet that can be fabricated from said alloys. Ce 2Co 16Ti has a high magnetic anisotropy (H a = 65 kOe) but a relatively low saturation magnetization (M s = 7.3 kG), and La 2Co 16Ti has a high Ms(9.5 kG) but Ha too low for most applications (16 kOe). Though these two end-members have previously well-known properties, changing economic conditions have made re-examination of systems containing cerium and lanthanum necessary as the economic viability of rare earth mining becomes dependent on extraction of products beyond what is currently considered useful and profitable within the rare earth elements. We find that replacing some lanthanum with cerium in La 2Co 16Ti increases H a by a factor of more than two, while decreasing M s by less than 5%. The measured Ms indicate maximum possible energy products in excess of 20 MG·Oe in these materials, which have Curie temperatures near 600 °C. Real energy productsmore » are expected to be greatest near x = 1. In conclusion, these findings identify La xCe 2-xCo 16Ti as a promising system for development of so-called gap magnets that fill the energy product gap between expensive rare-earth magnets and current non-rare earth alternatives.« less

Authors:
 [1];  [1];  [1];  [1];  [1]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science & Technology Division
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Critical Materials Institute (CMI)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)
OSTI Identifier:
1337487
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Alloys and Compounds
Additional Journal Information:
Journal Volume: 695; Journal ID: ISSN 0925-8388
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Permanent magnet; Magnetic anisotropy; Critical materials; La2Co16Ti; Ce2Co16Ti; Ce2Co17; Th2Ni17; Th2Zn17

Citation Formats

Conner, Benjamin S., McGuire, Michael A., Veedu, Shanavas Kavungal, Parker, David S., and Sales, Brian C. Evolution of structural and magnetic properties in LaxCe2-xCo16 Ti for $0 \leq x \leq 2$. United States: N. p., 2016. Web. doi:10.1016/j.jallcom.2016.11.078.
Conner, Benjamin S., McGuire, Michael A., Veedu, Shanavas Kavungal, Parker, David S., & Sales, Brian C. Evolution of structural and magnetic properties in LaxCe2-xCo16 Ti for $0 \leq x \leq 2$. United States. doi:10.1016/j.jallcom.2016.11.078.
Conner, Benjamin S., McGuire, Michael A., Veedu, Shanavas Kavungal, Parker, David S., and Sales, Brian C. 2016. "Evolution of structural and magnetic properties in LaxCe2-xCo16 Ti for $0 \leq x \leq 2$". United States. doi:10.1016/j.jallcom.2016.11.078. https://www.osti.gov/servlets/purl/1337487.
@article{osti_1337487,
title = {Evolution of structural and magnetic properties in LaxCe2-xCo16 Ti for $0 \leq x \leq 2$},
author = {Conner, Benjamin S. and McGuire, Michael A. and Veedu, Shanavas Kavungal and Parker, David S. and Sales, Brian C.},
abstractNote = {Here we examine the intrinsic magnetic and structural properties of the title alloys, permanent magnet materials based on the abundant rare-earth elements lanthanum and cerium, since these properties (TC, MsHa(K1, K2)) will set the upper limits on the quality of permanent magnet that can be fabricated from said alloys. Ce2Co16Ti has a high magnetic anisotropy (Ha = 65 kOe) but a relatively low saturation magnetization (Ms = 7.3 kG), and La2Co16Ti has a high Ms(9.5 kG) but Ha too low for most applications (16 kOe). Though these two end-members have previously well-known properties, changing economic conditions have made re-examination of systems containing cerium and lanthanum necessary as the economic viability of rare earth mining becomes dependent on extraction of products beyond what is currently considered useful and profitable within the rare earth elements. We find that replacing some lanthanum with cerium in La2Co16Ti increases Ha by a factor of more than two, while decreasing Ms by less than 5%. The measured Ms indicate maximum possible energy products in excess of 20 MG·Oe in these materials, which have Curie temperatures near 600 °C. Real energy products are expected to be greatest near x = 1. In conclusion, these findings identify LaxCe2-xCo16Ti as a promising system for development of so-called gap magnets that fill the energy product gap between expensive rare-earth magnets and current non-rare earth alternatives.},
doi = {10.1016/j.jallcom.2016.11.078},
journal = {Journal of Alloys and Compounds},
number = ,
volume = 695,
place = {United States},
year = 2016,
month =
}

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