JPS60204862A - Rare earth element-iron type permanent magnet alloy - Google Patents

Abstract

PURPOSE:To obtain a rare earth element-iron type permanent magnet alloy having superior magnetic characteristics even when a bulk material is formed by a conventional sintering method, by adding a third element to a rare earth element-iron (R-Fe) type binary alloy to form a ternary alloy. CONSTITUTION:This rare earth element-iron type permanent magnet alloy is represented by the formula (where R is one or more among Ce, Y, Pr, Nd, Sm and misch metal, X is one or more among C, N, O, P, H, S, Al and Si, 0.001<= alpha<=0.5, 0.5<=beta<=0.95, and alpha+beta<1).

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a rare earth iron-based permanent magnet alloy that can be formed into a bulk material with excellent magnetic properties by a sintering method.

[Technical background of the invention and its problems]

Intermetallic compounds consisting of rare earth metals (R) and iron (Fs) have large magnetocrystalline anisotropy and high saturation magnetization, and are promising as permanent magnet alloys with high coercive force and high energy product. Compared to rare earth cobalt magnets, it has advantages such as cheaper raw materials and less dust.

Conventional rare earth iron-based permanent magnet alloys have been produced by appropriately annealing amorphous ribbons created by liquid quenching to obtain high coercive force (J, Magn
, Mater, 24 (1981) 125. J
.

Appl, Phys, 53 (1982) 316
1).

However, when conventional rare earth iron-based binary permanent magnet alloys are melted, crushed, and then sintered to form a bulk shape, even after optimal heat treatment, only a low coercive force can be obtained, making it practical for practical use. This was insufficient as a permanent magnet.

[Purpose of the invention]

The present invention has been made based on various researches in view of the above points, and has been developed as a rare earth material that has high magnetic flux density, high coercive force, and retains a high energy product even when a bulk material is formed by a sintering method that allows easy processing into arbitrary shapes. The purpose is to provide an iron-based permanent magnet alloy.

[Summary of the invention]

The present invention creates a ternary alloy by adding a third element to the R-Fe binary system of rare earth iron, which has excellent magnetic properties even if it is formed into a bulk material by a normal sintering method. It is an iron-based permanent magnet alloy.

That is, the present invention has the general formula R4-α-βXαFeβ [where R
are Y, Co, Pr, Nd, Sml M, M (
One or more types of Mitsushmetal), Xke C, N,
O, P, H.

one or more of S, At, 81], and the range of α and β is 0.001≦α≦0.5゜0.5≦β≦0゜95. It is characterized by being defined by α+β<1.0.

In the present invention, the third element X added to the R-Fe binary system is C, N, O, P, H, S, A/! ,, 8
1st prize is mentioned. By adding these third elements The coercive force is improved by imparting properties. As X, C is particularly effective, but if necessary,
B may be added in an atomic ratio of 0.001 to 0.05. This composite addition can improve the squareness of the 4πM-H curve. The amount of B added is 0.00
When it is less than 1, no improvement in squareness is observed, and when it exceeds 0.05, the magnetic flux density decreases and the maximum energy product becomes small.

In this case, if the atomic ratio of the addition amount α of If a large amount of X is added exceeding the above range, the magnetic flux density will decrease, so the amount α of X to be added is defined in the above range. Preferably 0.0
The range is 4≦α≦020.

Fa has an effective effect in improving the magnetic flux density in the magnet alloy of the present invention, and if the added amount β is less than 0.5, a sufficient ternary crystal structure cannot be obtained and the magnetic flux density also decreases. . Further, if the amount of Fe added exceeds 0.95 and the coercive force decreases, it is necessary to specify the above range, and the range of 0.6≦β≦0.86 is particularly preferable.

Rare earth elements R include Y, Ce, Pr, Nd+S
m.

These include M, M, etc., and these are essential elements for improving coercive force, and if the amount added is small, the coercive force is extremely reduced, so a range of O,OS to 0.30 is preferable.

After melting and pulverizing the alloy having the above composition, it is compacted, and the obtained powder compact is sintered and then heat-treated to form a permanent magnet.

[Embodiments of the invention]

(Example) Alloy samples A1 to A22 having the compositions shown in Tables 1 and 2 were high-frequency melted, coarsely pulverized using a jet crusher Brown mill, and then finely pulverized using a jet mill. In this case, a grinding medium and N2 gas are used, and the average particle size of the particles obtained is 5 μm. After orienting this fine powder in a magnetic field of 15 KOe, it was pressed at a pressure of 2 tons/cIIL3 perpendicular to the direction of magnetic field application and compression molded to form a shape of 10 cm vertically, 10 cm horizontally, and 8 cm thick.
A plate-shaped powder compact (2) was obtained.

Next, after sintering this powder compact, it is heat-treated to form a permanent magnet, and its residual magnetic flux density: Br, coercive crab IH
a, and the maximum energy product: (BH)mlLX were measured, and the results are shown in Tables 1 and 2.

As the sintering conditions and heat treatment conditions for the powder compact, any one of the following conditions A, B, and C was used.

A: After sintering the powder compact at 1100° C. for 1 hour in an argon atmosphere, an aging treatment is performed at 600° C. for 5 hours.

B: After sintering the compacted powder in an argon atmosphere at 1080°C for 1 hour, it is subjected to two-step aging treatment at 650°C for 3 hours and 550°C for lθ hours.

C: After sintering the powder compact in an argon atmosphere at 1050°C for 1 hour, aging treatment was performed at 550°C for 5 hours, and then controlled cooling was performed at a cooling rate of 1°C/min to room temperature.

[Effects of the Invention] As is clear from the results in the above table, the rare earth iron-based permanent magnet alloy according to the present invention can be easily processed into any shape by the sintering method. Even if a bulk material is formed by this method, it has remarkable effects such as high magnetic flux density, high coercive force, and high energy product.

Claims (1)

[Claims] General formula R, -a-/XaF11/ [where R is Y, Co5Pr, Nd, Sm, M,
One or more types of M (Mitsushmetal)
≦0.5 0.5≦β≦0.95 α+β<1.0 A rare earth iron-based permanent magnet alloy.