Permanent magnet superior in resistance to oxidation
Abstract
Abstract PURPOSE:To obtain a superior magnet having extremely high energy products, high residual flux density, high coercive force, and high resistance to oxidation at a low cost by preliminarily using light rare earth elements full of resources with Nd and Pr as leading elements for R and using Fe, B, and R as main components. CONSTITUTION:It is assumed that at least one kind among rare earth elements including Y is in the range 8-30atom%, B 2-28atom%, and Fe 42-90atom%. The fact that the main phase of a crystal is tetragonal one is essential to make sintered permanent magnet having superior magnetic characteristics. It is shown that the maximum energy products (BH)max is not less than 10MGOe in the most desirable composing range. The maximum value amounts up to 25MGOe or more. For example, ingot fine powder is inserted into a mold and oriented in a magnetic field, and the obtained molded body is sintered and then cooled, and moreover, it is given age-treating, thereby to obtain the permanent magnet.
Inventors
- 👤 Hideya Sakurai
- 👤 桜井 秀也
- 👤 Masato Sagawa
- 👤 佐川 真人
- 👤 Tetsuharu Hayakawa
- 👤 早川 徹治
Bibliographic Details
Claims Analysis
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