Magnetic properties of icosahedral Al-Cr-Mn-Ge alloys

Journal Article · Sun Apr 01 00:00:00 EST 1990 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.41.6933· OSTI ID:6949920

McHenry, M E ^[1]; Dunlap, R A; Srinivas, V ^[2]; Bahadur, D ^[3]; O'Handley, R C ^[4]

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1. Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (USA) Department of Metallurgical Engineering Materials Science, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (USA)
2. Department of Physics, Dalhousie University, Halifax, Nova Scotia, Canada B3H3J5 (CA)
3. Advanced Centre for Materials Science, Indian Institute of Technology, Kanpur, India 208016 (IN)
4. Department of Materials Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (USA) Department of Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (USA)

Alloys in the series Al{sub 65}Cr{sub 20{minus}{ital x}}Mn{sub {ital x}}Ge{sub 15} (0{le}{ital x}{le}20) have been produced by melt spinning. These rapidly solidified alloys have been found to be single phase and of the icosahedral structure. Magnetic-susceptibility measurements reveal a moment of 0.45{mu}{sub {ital B}} for Cr in the Al{sub 65}Cr{sub 20}Ge{sub 15} alloy. This is the first observation of a local moment on Cr in a quasicrystal. In the Al{sub 65}Mn{sub 20}Ge{sub 15} alloy a moment of 2.10{mu}{sub {ital B}} for Mn is observed, which is the largest moment observed in Al-Mn-metalloid quasicrystal alloys. The compositional dependence of the magnetic moment is consistent with at least two classes of magnetic sites. Spin-glass behavior is observed below 8 K in the Al{sub 65}Mn{sub 20}Ge{sub 15} alloy. Measurements of the time dependence of the magnetization, in a field of 1 T, and from the zero-field-cooled state have been made for the Al{sub 65}Mn{sub 20}Ge{sub 15} alloy, revealing logarithmic relaxation. Analysis of this data using a first-order rate equation and a distribution of energy barriers reveals an average energy barrier of 6.8 meV.

• OSTI ID: 6949920
• Journal Information: Physical Review, B: Condensed Matter; (USA), Vol. 41:10; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
MAGNETIC MOMENTS
CHROMIUM ALLOYS
GERMANIUM ALLOYS
MANGANESE ALLOYS
CURIE POINT
LOW TEMPERATURE
MAGNETIC SUSCEPTIBILITY
MEDIUM TEMPERATURE
QUANTITY RATIO
RELAXATION
SPIN GLASS STATE
ULTRALOW TEMPERATURE
VERY LOW TEMPERATURE
ALLOYS
MAGNETIC PROPERTIES
PHYSICAL PROPERTIES
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE
360104* - Metals & Alloys- Physical Properties