JPS6111441B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is a 3D material mainly containing rare earth elements and cobalt.
This invention relates to the improvement of R--Co--Cu--Fe based permanent magnet alloys that are mainly composed of R ₂ Co ₁₇ type intermetallic compounds made of transition metals. In general, R ₂ Co ₁₇ -based magnet alloys have an extremely large theoretical maximum energy product compared to RCo ₅ alloys, making them promising magnet materials, but the maximum energy product currently obtained is considerably lower than the theoretical value. In addition, it has low magnetocrystalline anisotropy and low coercive force, making it unsuitable for thin magnet materials. However, the saturation magnetic flux density of R ₂ Co ₁₇ alloy,
Therefore, since Br itself is superior to RCo ₅ alloys, it can be expected to have an excellent maximum energy product by improving coercive force (IHc). From this perspective, the present inventors used the R-Co-Cu-Fe system, which is a typical alloy of the R ₂ Co ₁₇ system, as the basic composition, and investigated in detail the effects of various component elements on the coercive force. As a result, we found that adding a small amount of boron was extremely effective. Furthermore, it has been found that by adding titanium and vanadium together within a limited range together with boron, the effect of improving coercive force is more pronounced. That is, the present invention has (1) weight percentages of R (one or more of Y and rare earth elements): 20-35%, Cu: 5-15%, Fe: 3-35%;
20%, B: 0.002 to 0.5% R ₂ Co ₁₇ type permanent magnet material with the balance essentially consisting of Co. (2) Weight percentage R (Y and one or more rare earth elements): 20-35%, Cu: 5-15%, Fe: 3-35%
20%, B: 0.002 to 0.5%, and 20% each of one or more elements selected from Ti and V.
and contains B/Ti+V in a range of 0.1 or more, with the remainder substantially consisting of Co.
R ₂ Co ₁₇ type permanent magnet material. Next, the reason for limiting the component range of the magnet material of the present invention will be described below. R: 20 to 35% In order to ensure an excellent (BH)max in the basic composition of the R-Co-Cu-Fe system, it is necessary to add 20% or more of R. On the other hand, if added in a large amount, Br will be low and the maximum energy product will not only decrease, but it will also be economically disadvantageous, so it was limited to 35% or less. In addition to Sm, R includes La, Ce, Pr, Nd,
En, Gd, Tb, Dy, Ho, Er, Pm, Tm, Yb,
Either Lu or Y may be used. Cu: 5-15% Excellent in basic composition of R-Co-Cu-Fe system
In order to ensure IHc, it is necessary to add 5.0% or more of Cu. However, adding a large amount lowers Br and reduces the maximum energy product, so it was limited to 15% or less. Fe: 3-20% Excellent in basic composition of R-Co-Cu-Fe system
In order to secure Br, it is necessary to add 3.0% or more of Fe. However, since IHc decreases rapidly if added in large amounts, it was limited to 20% or less. B: 0.002 to 0.5% B is a main element in the magnet material of the present invention, and adding a small amount can significantly improve IHc.
In the case of the R-Co-Cu-Fe system, the effect is observed at additions of 0.002% or more, at which point boride begins to be extracted.
On the other hand, if a large amount is added, the non-magnetic boride occupancy becomes extremely large and Br and IHc decrease.
Limited to 0.5% or less. Also, when adding B, when using liquid phase sintering by low melting point eutectic formation with Co, Cu, Fe, etc.
Within the composition range of these components, the more the powder has a eutectic composition, the more liquid phase will be produced, and higher density of the sintered body can be expected. In addition, B acts as a deoxidizing agent during melting, and in the production of sintered magnets, it makes it easier to crush the powder during pulverization, resulting in a uniform and fine powder. At the same time, it promotes sintering, so it is also effective in improving the material properties for magnetism, etc. Therefore, the effect of adding B is significant in the case of the magnet material of the present invention. Ti, V: 1 type or 2 or more types, each 2.0% or less, and B/Ti + V: 0.1 or more The above elements form intermetallic compounds with B, have the effect of promoting the effect of B, and are effective in improving IHc. It is a valid element. However, if added in a large amount, Br decreases and the maximum energy product decreases, so it is desirable that each element be added individually in an amount of 1.5% or less, and that the total amount be 10 times or less than the B content. Next, the characteristics of the magnet material of the present invention will be explained in detail using examples. Example 1 Using a button arc melting furnace adjusted to an argon atmosphere, the basic components were 27% Sm-10% Cu-7% Fe-Co, and further B was 0.005%, 0.03%, 0.15%,
Six types of alloys with additions of 0.27%, 0.041% and 0.70% were produced. This was coarsely pulverized in a mortar and then pulverized in a jet mill to an average particle size of about 4 μm. In this case, the alloy containing more B was ground to a predetermined particle size in a shorter time. The above powder was press-molded under a pressure of about 5 t/cm ² in a magnetic field with 10 KOe applied. This compact was sintered at 1200°C for 1 hour in an argon atmosphere, followed by solution treatment, and then aged at 800°C. The magnetic properties of each sintered body produced by the above method were investigated. The results are shown in Figure 1, organized by B content. As seen in the same figure, as the B content increases
There is a tendency for Br to gradually decrease. On the other hand, IHc increases rapidly, indicating that (BH)max also improves markedly. However, if the B content is 0.3% or more, IHc,
Both Br begins to decrease, and at 0.5% or more, (BH)max becomes lower than that without B. As above, 27Sm―10Cu―
Adding a small amount of B to 7Fe-Co alloy (BH)
This shows that it is extremely effective in improving max. Example 2 29Sm-10.8Cu remaining by the same procedure as Example 1
An alloy made of Co was produced. In addition, the above alloy was mixed with 7% by weight of pure Fe prepared separately, and the same alloy was mixed with 3.8% B of Fe-
A mixture of 7% by weight of lump B was separately coarsely ground and then finely ground using a jet mill. The above two types namely 27Sm-10Cu-7Fe-Co and 27Sm-
A mixed powder of 10Cu-7Fe-0.26B-Co was molded in a magnetic field (10KOe applied) with a press pressure of 5t/ ^cm2 , and this was sintered at 1180℃ for 1 hour in an argon atmosphere. After solution treatment, it was aged at 800℃. Next, the magnetic properties of the above sintered body were investigated. The results are also shown in Figure 1 with an x mark. As seen in the figure, the 27Sm―10Cu― used in this example
The 7Fe--Co alloy exhibits almost the same magnetic properties as the alloy system of Example 1. On the other hand, the 27Sm-10Cu-7Fe-0.26B-Co alloy of this example has a higher sintered density, IHc, and
It shows that both (BH) max are significantly superior. In addition, the B-containing alloy of this example has a higher sintered density, Br, (BH) than the B-containing alloy of Example 1.
Both max are excellent. This is because the melting point of the Fe-B powder itself is low (approximately 1150℃), so the Fe-B powder becomes a liquid phase during sintering, which improves the density of the sintered body. This seems to have contributed greatly to the improvement. In addition to Fe-B, Co-B (melting point: 1100
℃), Cu-B (melting point: 1060℃), etc. Example 3 27Sm-10Cu-7Fe was prepared using the same procedure as in Example 1.
-0.12B-Co was the basic composition, and 8 types of alloys were made by adding Ti, V, and Zr singly or in combination to this, and after coarsely pulverizing them, they were finely pulverized using a jet mill. A molded body was produced from the above powder at a pressing pressure of 5t/ ^cm2 in a magnetic field (10KOe applied), and this was molded at 1200 m2 in an argon atmosphere.
Sintering was performed for 1 hour at ℃, followed by solution treatment and aging treatment at 800℃. Next, the magnetic properties of the above sintered body were investigated. The results are shown in Table 1.

[Table] As seen in the same table, each with B is 2.0.
Sample materials No. 2 and 4 with Ti and V added below % have a lower resistance than No. 1 to which these elements are not added.
IHc and (BH)max have clearly improved. However, as in No. 3, if the amount of Ti is too large relative to the amount of B, IHc and (BH)max are shown to actually decrease. In addition, as a result of detailed investigation into the effective range of Ti and V amounts, we found that each
It was confirmed that the B content is preferably 2.0% or less, and the total amount is preferably 10 times or less than the B content. As described above, the magnet material of the present invention contains a small amount of B or Ti and V added to it alone or in combination.
R ₂ Co ₁₇ type magnet alloy, which significantly improves the coercive force (IHc) of conventional magnet alloys of this type and therefore has an excellent maximum energy product.
It is a Cu-Fe based magnet material.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the relationship between boron content and magnetic properties.

Claims (1)

[Claims] 1 Weight percentage: R (Y and one or more rare earth elements): 20 to 35%, Cu: 5 to 15%, Fe: 3 to 20
%, B: 0.002 to 0.5%, R ₂ Co ₁₇ type permanent magnet material with the remainder substantially consisting of Co. 2 Weight percentage R (Y and one or more rare earth elements): 20-35%, Cu: 5-15%, Fe: 3-20
%, B: 0.002 to 0.5%, and further contains 20% or less of one or two elements selected from TiV, and in a range of B/Ti + V = 0.1 or more, with the remainder substantially consisting of Co. Becomes R ₂ Co ₁₇ type permanent magnet material.