Synthesis of high-energy magnet materials: Coercivity mechanism, surface studies, and new alloys

Technical Report · Sun Jan 01 00:00:00 EST 1989

OSTI ID:6260874

Wallace, W E; Sankar, S G; Elbicki, J M; Cheng, S F

To date, in spite of extensive studies, only five energy permanent magnet materials have been discovered. Hence there is an ongoing search for new materials, One, SmTi(Fe,Co)11, is promising. One characteristic required on a material is high uniaxial magnetic anisotropy. This is supplied by the rare earth crystal field interaction. This interaction is now understood well enough to have predictive value. A new use of Auger spectroscopy has revealed that the grains in Nd-Fe-B magnets are covered by a neodymium-rich film about 30-50 A thick. This iron-deficient layer is proposed to be of crucial value for high coercivity. High energy magnets are in widespread use but mostly in high technology applications. Cheaper magnets are needed for normal uses, e.g., household appliances. Lowering cost and obtaining higher flux materials are the greatest technological challenges. Understanding coercivity is the greatest scientific challenge.

• Research Organization: Carnegie-Mellon Univ., Pittsburgh, PA (USA). Dept. of Metallurgical Engineering and Materials Science
• OSTI ID: 6260874
• Report Number(s): AD-A-226152/7/XAB; CNN: DAAL03-87-K-0150
• Resource Relation: Other Information: Pub. in Jnl. of Materials Science and Engineering, Vol. B3, 351-354(1989)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
PERMANENT MAGNETS
MAGNETIC MATERIALS
ANISOTROPY
AUGER ELECTRON SPECTROSCOPY
COBALT ALLOYS
COST
ENERGY
IRON ALLOYS
MAGNETIC FIELDS
MAGNETIC PROPERTIES
RARE EARTH ALLOYS
SAMARIUM ALLOYS
SYNTHESIS
TITANIUM ALLOYS
ALLOYS
ELECTRON SPECTROSCOPY
MAGNETS
MATERIALS
PHYSICAL PROPERTIES
SPECTROSCOPY
360104* - Metals & Alloys- Physical Properties