High coercivity Nd-Fe-B magnets with lower dysprosium content

Journal Article · Fri Apr 15 04:00:00 EDT 1988 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.340728· OSTI ID:5328783

Kim, A S

The elements Dy and Al play very important roles in the magnetic properties of Nd-Fe-B base compounds. The proper combination of Dy and Al may provide a significant improvement in the magnetic properties. With this in mind, close examinations have been made of the magnetic properties of several (Nd,Dy)-(Fe,Al)-B alloys. As a result, (Nd,Dy)-(Fe,Al)-B alloys containing equal atomic amounts of Dy and Al have been found to provide superior permanent magnetic properties. When compared to Nd-Dy-Fe-B or Nd-Fe-Al-B alloy of equivalent Dy or Al content, they have a much higher H/sub c//sub i/ . The reduction in B/sub r/ associated with the addition is markedly less. The H/sub c//sub i/ of the alloys increases linearly with Dy content at a rate of about 7.5 kOe/at. % Dy, when the alloys contain equal atomic amounts of Dy and Al; or, approximately 1.4 x the rate of (Nd,Dy)-Fe-B alloys. When Al is present, much less Dy is required to reach a given coercivity level. Thus, a magnet with high (BH)/sub max/ and H/sub c//sub i/ can be more economically produced with Nd-Dy-Fe-Al-B alloys. The small Al additions, as described above, result in higher coercivities and lower irreversible losses at elevated temperatures without increasing temperature coefficients, and thus extend the application temperature range.

• Research Organization: I G Technologies, Inc., 405 Elm Street, Valparaiso, Indiana 46383
• OSTI ID: 5328783
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 63:8; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
ALLOYS
ALUMINIUM ADDITIONS
ALUMINIUM ALLOYS
BORON ALLOYS
COERCIVE FORCE
CURIE POINT
DYSPROSIUM ADDITIONS
DYSPROSIUM ALLOYS
HIGH TEMPERATURE
IRON ALLOYS
IRON BASE ALLOYS
MAGNETIC PROPERTIES
MAGNETS
MATERIALS
MEDIUM TEMPERATURE
NEODYMIUM ALLOYS
PERFORMANCE
PERMANENT MAGNETS
PHYSICAL PROPERTIES
RARE EARTH ADDITIONS
RARE EARTH ALLOYS
SINTERED MATERIALS
TEMPERATURE EFFECTS
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE