Alloy for bonded magnets, isotropic magnet powder and anisotropic magnet powder and their production method, and bonded magnet
AssigneeAichi Steel Corporation
InventorsYoshinobu Honkura, Norihiko Hamada, Chisato Mishima
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Abstract
An alloy for bonded magnets of the present invention includes at least a main component of iron (Fe), 12-16 atomic % (at %) of rare-earth elements (R) including yttrium (Y), and 10.8-15 at % of boron (B), and is subjected to a hydrogen treatment method as HDDR process or d-HDDR process. Using the magnet powder obtained from carrying out d-HDDR processing, etc. on this magnet alloy, pellets with superior insertion characteristics into bonded magnet molding dies can be obtained, and bonded magnets with superior magnetic properties and showing low cost can be obtained.
Claims17
An alloy for bonded magnets including at least a main component of iron (Fe) and
- 12-16 atomic % (at %) of a rare-earth element including yttrium (Y) (hereafter referred to as “R”), and
- boron (B) of 10.8-15 at %.
An isotropic magnet powder made from HDDR process having
- a hydrogenation step where an alloy ingot including at least a main composition of Fe, 12-16 at % of R including Y and 10.8-15 at % of B is maintained in a hydrogen gas atmosphere at 1023-1173 K, and
- after said hydrogenation step, an desorption step where hydrogen is removed.
An anisotropic magnet powder made from d-HDDR process having
- a low-temperature hydrogenation step where an alloy ingot including at least a main composition of Fe, 12-16 at % of R including Y and 10.8-15 at % of B is maintained in a hydrogen gas atmosphere at not more than 873 K, and
- after said low-temperature hydrogenation step, a high-temperature hydrogenation step where it is maintained in a hydrogen gas atmosphere at 20-100 kPa and 1023-1173 K, and
- after said high-temperature hydrogenation step, a first evacuation step where it is maintained in a hydrogen gas atmosphere at 0.1-20 kPa and 1023-1173 K, and
- after said first evacuation step, a second evacuation step where the hydrogen is removed.
A bonded magnet made by compression molding of a mixture of a binder and an isotropic magnet powder obtained by HDDR processing comprising a hydrogenation step where an alloy ingot including at least a main component of Fe, 12-16 at % of R including Y, and 10.8-15 at % of B is maintained in a hydrogen gas atmosphere at 1023-1173 K, and after said hydrogenation step, an desorption step where hydrogen is removed.
A bonded magnet made by compression molding of a mixture of a binder and an anisotropic manget powder obtained by d-HDDR process comprising a low-temperature hydrogenation step where an alloy ingot including at least a main component of Fe, 12-16 at % of R including Y, and 10.8-15 at % of B is maintained in a hydrogen gas atmosphere at not more than 873 K, and after said low-temperature hydrogenation step, a high-temperature hydrogenation step where it is maintained under a hydrogen gas atmosphere at 20-100 kPa and 1023-1173 K, and after said high-temperature hydrogenation step, a first evacuation step where it is maintained under a hydrogen gas atmosphere at 0.1-20 kPa and 1023-1173 K, and after said first evacuation step, a second evacuation step where the hydrogen is removed.
A production method of an isotropic magnet powder obtained by HDDR processing comprising a hydrogenation step where an alloy ingot including at least a main component of Fe, 12-16 at % of R including Y, and 10.8-15 at % of B is maintained in a hydrogen gas atmosphere at 1023-1173 K, and after said hydrogenation step, an desorption step where hydrogen is removed.
A production method of an anisotropic magnet powder obtained by d-HDDR process having
- a low-temperature hydrogenation step where an alloy ingot including at least a main composition of Fe, 12-16 at % of R including Y and 10.8-15 at % of B is maintained in a hydrogen gas atmosphere at not more than 873 K, and
- after said low-temperature hydrogenation step, a high-temperature hydrogenation step where it is maintained in a hydrogen gas atmosphere at 20-100 kPa and 1023-1173 K, and
- after said high-temperature hydrogenation step, a first evacuation step where it is maintained in a hydrogen gas atmosphere at 0.1-20 kPa and 1023-1173 K, and
- after said first evacuation step, a second evacuation step where the hydrogen is removed.
Dependencies are inferred from the claim text.