Magnetic and microstructure properties of iron-rare earth-boron magnets

Thesis/Dissertation · Wed Jan 01 00:00:00 EST 1986

OSTI ID:5256472

Tao, Y F

The new generation of cobalt-free Fe-Nd-B permanent magnets have excellent hard magnetic properties attributed to a tetragonal Fe/sub 14/Nd/sub 2/B phase that has a high anisotropy and a high magnetic moment. The purpose of this work was to study the magnetic and microstructure properties of the iron-rare earth-boron based systems. The magnets were mostly made from heat-treated melt-spun samples. The addition of Co and Tb (Dy) in the Fe-Nd-B compounds enhances the relatively low Curie temperature and the coercivity, respectively. These outstanding hard magnetic properties find wide applications in industry. Partial substitution of boron by other metalloids (Si, C, P) leads to a substantial decrease in properties of hard magnetic materials and to a substantial decrease in Curie temperature. The spin-reorientation temperature in Fe-Nd-B alloys was found to drop drastically with partial substitution of Fe by Ni, Mn and B by C, Si. The origin of high coercivity was examined by correlating the hard magnetic properties with the microstructure. The high coercivities can be explained by domain wall pinning at grain boundaries.

• Research Organization: Kansas State Univ., Manhattan (USA)
• OSTI ID: 5256472
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BORON ALLOYS
MAGNETIC PROPERTIES
MICROSTRUCTURE
IRON ALLOYS
NEODYMIUM ALLOYS
PERMANENT MAGNETS
MATERIAL SUBSTITUTION
COBALT ADDITIONS
COERCIVE FORCE
SEMIMETALS
ALLOYS
COBALT ALLOYS
CRYSTAL STRUCTURE
ELEMENTS
MAGNETS
PHYSICAL PROPERTIES
RARE EARTH ALLOYS
360104* - Metals & Alloys- Physical Properties
360102 - Metals & Alloys- Structure & Phase Studies