JPH0242894B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to improvements in Al--Ni permanent magnet alloys with good magnetic properties.

[Conventional technology]

Alnico magnets whose main component is Al―Ni―Co are
It has been used as a permanent magnet for generators and motors for a long time because it has many advantages such as excellent magnetic properties, little change in magnetic properties due to temperature, and good manufacturability. However, Co
Alnico magnets containing Co at a high proportion of 20% or more are disadvantageous in terms of material costs because Co is an expensive material and its price fluctuates rapidly. Therefore, magnetic alloys that reduce the amount of Co used or, if possible, do not use Co, are being reconsidered. A typical example is Al-Ni magnet, which has Al-Ni as its main component, but it cannot be said to have high magnetic properties.
Furthermore, there were problems such as large variations in magnetic properties due to differences in cooling rates after solution treatment, and there was room for improvement.

[Problem to be solved by the invention]

An object of the present invention is to solve the above-mentioned problems inherent in Alni magnets, and to provide a magnet alloy with improved magnetic properties and reduced variation.

[Means to solve the problem]

The Alni-based magnetic alloy of the present invention basically has the following characteristics:
Ni: 15.0-28.0%, Al: 9.0-15.0% and V:
It is a permanent magnet alloy containing 0.1 to 0.5% Fe, with the remainder essentially consisting of Fe. In addition to the above basic composition, this alloy also has
Co: 13.0% or less, Cu: 8.0% or less and Ti: 5.0%
The composition may include one or more selected from the following. In both of the above cases, the melted permanent magnet alloy is subjected to solution treatment at a temperature of 1100 to 1200°C to adjust the structure to a single α phase, and then the temperature range from 1150 to 600°C is 20°C/sec or less. The magnetic properties are improved by lowering the temperature at a cooling rate of . If it is desired to particularly increase the residual magnetic flux density among the magnetic properties, it is preferable to perform an aging treatment at a temperature of 600 to 700° C. after the solution treatment.

[Effect]

The reason why the composition of the permanent magnet alloy of the present invention was selected as described above is as follows. Ni: 15.0 to 28.0% Ni is a main element constituting the Alni magnet along with Al, and if its amount is small, the coercive force H _c cannot be ensured. On the other hand, if it is too large, the residual magnetic flux density B _r
becomes lower. Appropriate range is 15.0-28.0% above
It is. Al: 9.0 to 15.0% Al is also a major constituent element, and as with Ni, if it is too low, the coercive force will be low, and if it is high, the residual magnetic flux density will be low. 9.0~15.0 above
A range of % is suitable for matching properties. V: 0.10-5.0% Magnetic properties are improved by using V in place of Co. At the same time, the heat treatment sensitivity is improved, that is, the optimum cooling rate range during solution treatment is widened, and manufacturing becomes easier. These effects can be obtained by adding 0.10% or more;
%, the residual magnetic flux density decreases. The following elements to be optionally added are as follows:
Further improves magnetic properties. Co: 13.0% or less The presence of Co brings about reliable improvements in various magnetic properties. However, adding a large amount goes against the original purpose of the invention, which is to reduce cobalt content.
The upper limit was set at 13.0%, where the effect growth slows down. Cu: 8.0% or less Coercive force increases by containing Cu. on the other hand,
Adding a large amount will also result in a decrease in the residual magnetic flux density, so it should be limited to 8.0% or less. Ti: 5.0% or less Addition of Ti improves coercive force. However, if added in a large amount, the residual magnetic flux density decreases, so it was set at 5.0% or less. As mentioned above, the magnetic properties of conventional Alni magnet alloys tend to vary depending on the cooling rate after solution treatment, so cooling must be controlled within a narrow range of about 5 to 10°C/sec. However, with the permanent magnet alloy of the present invention, even when cooled at a wide cooling rate of 20°C/sec or less, as described above,
A product with stable quality can be obtained.

【Example】

An Alni-based magnet alloy having the alloy composition shown in the table was melted and poured into a shell mold to form a cylindrical body. After solution treatment by heating at 1150°C for 30 min, the temperature was lowered to room temperature at various cooling rates ranging from 0.5 to 100°C/sec, and then at 650°C for 3 hours.
Aging treatment was applied. Magnetic properties after solution treatment and aging treatment,
They are also shown in the table. From a comparison of the data of the Examples and Comparative Examples, it is clear that the permanent magnet alloys of the present invention have improved magnetic properties than conventional Alni magnet alloys. In addition, the data of Example Nos. 4 to 10 are optionally added elements.
This shows the effects of Co, Cu, and Ti. When we investigated the influence of the cooling rate after solution treatment on various magnetic properties, we found that Comparative Example No. 1 had a
While it was clear that the characteristics deteriorated at temperatures below ℃/min and above 10℃/min, in Example No.
Almost unchanged results were obtained within the range of 20°C/sec.

【table】

【table】

【Effect of the invention】

The permanent magnet alloy of the present invention is cheaper than Alnico magnets, but is an improvement over Alnico magnets, which have inferior magnetic properties and unstable quality. In other words, by not using expensive Co at all or using only a small amount, we have achieved good magnetic properties while keeping the price low. Furthermore, since the preferred range of cooling rates after solution treatment has been expanded, productivity has increased and products with stable quality can now be easily obtained. Therefore, the permanent magnet alloy of the present invention can be used not only for conventional Alni magnets but also for a wide range of other uses.

Claims (1)

[Scope of Claims] 1. A permanent magnet alloy containing 15.0 to 28.0% Ni, 9.0 to 15.0% Al, and 0.1 to 5.0% V, with the balance substantially consisting of Fe. 2 In addition to Ni: 15.0-28.0%, Al: 9.0-15.0% and V: 0.1-5.0%, Co: 13.0% or less, Cu:
Permanent magnetic alloy containing one or more selected from 8.0% or less and Ti: 5.0% or less, with the remainder substantially consisting of Fe.