Magnetic properties of LaCo sub 13 -based systems

Journal Article · Tue May 01 04:00:00 EDT 1990 · Journal of Applied Physics; (USA)

DOI:https://doi.org/10.1063/1.344695· OSTI ID:6838225

Ido, H; Sohn, J C; Pourarian, F; Cheng, S F; Wallace, W E ^[1]

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1. MEMS Department, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (USA)

Four polycomponent systems based on LaCo{sub 13} have been studied: La(Co{sub 1{minus}{ital x}}Fe{sub {ital x}}){sub 13}, La(Co{sub 1{minus}{ital x}}Al{sub {ital x}}){sub 13}, La(Co{sub 1{minus}{ital x}{minus}{ital y}}Fe{sub {ital x}}Al{sub {ital y}}){sub 13}, and La{sub 0.7}Nd{sub 0.3}(Co{sub 0.7}Fe{sub 0.3}){sub 13}. These 1:13 systems were studied because of their potential for permanent magnet fabrication. LaCo{sub 13} has a high 3{ital d} metal content, the highest for any known rare-earth intermetallic, a 13 kG saturation induction, and a high {ital T}{sub {ital c}} (1318 K). Unfortunately, it is cubic and lacks anisotropy. The substituted systems were examined as a portion of a program to find LaCo{sub 13}-based systems of applications significance. Replacement of Co in LaCo{sub 13} by Fe and/or Al leads to a rapid decline in {ital T}{sub {ital c}} for all systems studied. Replacement of Co by Al results in a decline in moment, whereas replacement by Fe leads to a rise in moment to 2.39{mu}{sub {ital B}}/3{ital d} atom for La(Co{sub 0.4}Fe{sub 0.6}){sub 13}, as compared to 2.46{mu}{sub {ital B}}/3{ital d} atom for Fe{sub 0.7}Co{sub 0.3}. Analysis of the magnetic data shows that vacancies occur in both half-bands for LaCo{sub 13} (4.8 spin up and 3.24 spin down) but in only one half-band in La(Co{sub 1{minus}{ital x}}Al{sub {ital x}}){sub 13} for {ital x}{ge}0.2. Nd in these systems carries a moment of 3{mu}{sub {ital B}}, close to that of the free tripositive ion.

• OSTI ID: 6838225
• Journal Information: Journal of Applied Physics; (USA), Journal Name: Journal of Applied Physics; (USA) Vol. 67:9; ISSN 0021-8979; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
ALLOYS
ALUMINIUM ALLOYS
COBALT ALLOYS
COHERENT SCATTERING
CRYSTAL STRUCTURE
DIFFRACTION
IRON ALLOYS
LANTHANUM ALLOYS
MAGNETIC MOMENTS
MAGNETIC PROPERTIES
NEODYMIUM ALLOYS
PHYSICAL PROPERTIES
RARE EARTH ALLOYS
SAMPLE PREPARATION
SCATTERING
TEMPERATURE MEASUREMENT
X-RAY DIFFRACTION