Neutron diffraction studies of some rare earth-transition metal deuterides. Final report, 15 November 1983-1 December 1985

Technical Report · Thu May 01 04:00:00 EDT 1986

OSTI ID:5163558

James, W J

Neutron diffraction experiments were performed on Ho/sub 6/Mn/sub 23/. At 77K it is found to have a face-centered cubic crystal structure and a noncollinear magnetic structure, with the Ho moments tilted at an angle of 33.4 to the Mn moments. The Ho atom carries a moment of 3.8 mu sub B, while the Mn moments at the b, d, f/sub 1/ and f/sub 2/ sites are 2.1, 2.0, 2.2 and 1.9 ..mu../sub B/ respectively, comparable to those found in Y/sub 6/Mn/sub 23/. The very low moment on the Ho atom is rationalized as resulting from the fanning of the weakly coupled rare earth moments around the net Ho moment direction, giving a low spatially averaged value. Neutron-diffraction studies of three Y/sub 6/(Fe/sub 1-x/Al/sub x/)/sub 23/ compounds (x=0.05, 0.10, 0.15) at 523K and 77K reveal substantial preferential atomic ordering of Fe and Al atoms on the four transition crystallographic sites. The Fe atoms exhibit different magnetic moments on the four sites. The ternary alloys, Y/sub 6/(Fe/sub x/Mn/sub 1-x/)/sub 23/, exhibit interesting magnetic behavior over a range of solid solutions of iron and manganese. The effects of the substitution of Fe by Al in the R/sub 2/ (Fe/sub 1-x/Al/sub x/)/sub 14/B compounds (R = Y, rare earths) on their magnetic properties were investigated. The present experimental data indicate that intermetallic compounds based on Nd/sub 2/(Fe/sub 1-x/-yAl/sub x/CoY)/sub 14/B have both high Curie temperatures and high coercive fields. The magnetocrystalline anisotropy of (Nd/sub 1-x/Sm/sub x/)2Fe/sub 14/B and (Nd/sub 1-x/Pr/sub x/)/sub 2/Fe/sub 14/B was studied by x-ray and magnetic measurements.

• Research Organization: Missouri Univ., Rolla (USA). Materials Research Center
• OSTI ID: 5163558
• Report Number(s): AD-A-168995/9/XAB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104 -- Metals & Alloys-- Physical Properties
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
ALLOYS
ALUMINIUM ALLOYS
ANISOTROPY
ATOMS
BORON ALLOYS
COERCIVE FORCE
COHERENT SCATTERING
CRYSTAL STRUCTURE
CRYSTALS
DEUTERIDES
DEUTERIUM COMPOUNDS
DIFFRACTION
DISPERSIONS
ELEMENTS
HIGH TEMPERATURE
HOLMIUM ALLOYS
HYDRIDES
HYDROGEN COMPOUNDS
INTERMETALLIC COMPOUNDS
IRON ALLOYS
MAGNETIC FIELDS
MAGNETIC MOMENTS
MAGNETIC PROPERTIES
MAGNETS
MANGANESE ALLOYS
METALS
MIXTURES
NEODYMIUM ALLOYS
NEUTRON DIFFRACTION
PERMANENT MAGNETS
PHYSICAL PROPERTIES
RARE EARTH ALLOYS
SCATTERING
SOLID SOLUTIONS
SOLUTIONS
YTTRIUM ALLOYS