JP2588450B2 - Amorphous alloy ribbon with improved crystallization resistance of surface layer and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an amorphous alloy used for applications utilizing the properties of an amorphous alloy such as soft magnetic properties, high corrosion resistance and high strength, wherein the surface layer has a high crystallization resistance. The present invention relates to an amorphous alloy ribbon having resistance and a method for producing the same.

[0002]

2. Description of the Related Art An amorphous alloy is an alloy having a structure in which the arrangement of atoms is irregular, and can be produced by rapidly cooling an alloy having a specific composition from a liquid phase or a gas phase. The method of quenching from the liquid phase is generally called liquid quenching, which is a single-roll quenching method for forming ribbons, a centrifugal quenching method, a twin-roll method, a submerged spinning method for forming a wire,
The atomizing method and cavitation method for producing powder are known as typical production methods of the liquid quenching method.

[0003] Amorphous alloys have characteristic properties that cannot be obtained with conventional crystalline alloys due to irregularities in the atomic arrangement. Soft magnetic properties, high corrosion resistance and high strength are properties of an amorphous alloy that are excellent from a practical viewpoint. Many applications utilizing the properties of such amorphous alloys have been proposed and put to practical use. Magnetic cores, magnetic filters, magnetic shields, sensors, strength materials, and composite materials are typical examples.

On the other hand, amorphous alloys also have disadvantages. Particularly problematic in practice is thermal stability. Since an amorphous alloy is a non-equilibrium phase obtained by freezing a high-temperature stable phase, it is crystallized when the temperature is increased, and the excellent properties of the amorphous alloy are lost. The means conventionally taken to increase the thermal stability have been the proper selection of the alloy composition and the addition of elements that have the effect of increasing the crystallization temperature. Although these methods are effective for increasing the thermal stability, the compositions were balanced at the expense of the desired properties. For this reason, the excellent properties inherent in amorphous alloys have not been fully utilized.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an amorphous alloy ribbon which retains both excellent characteristics and thermal stability of an amorphous alloy, and a method for producing the same.

[0006]

The gist of the present invention is as follows. (1) a _{M a X b Si c B d} C e as a main component, and contains 0.01 to 1.0 wt% of Sn to main component,
Fabricated by single-sided cooling method, the thickness direction of the ribbon is measured from the surface of the ribbon.
In the surface layer whose distance measured in the direction is within 0.1μm or less
The Sn concentration whose width measured in the thickness direction is 0.03 μm or less
A segregation layer is formed, and the Sn peak concentration of the segregation layer is
An amorphous alloy ribbon having an Sn concentration of 5 times or more in luc and having improved crystallization resistance. Here, M is at least one of Fe, Co, and Ni, and X is Mo, Nb,
At least one of Ta, W, Cr, V, Mn, and Cu;
a: 60 to 90 (atomic%, the same applies hereinafter), b: more than 0 to 6,
c: 1 to 19, d: 7 to 20, e: more than 0 to 4, a + b +
c + d + e = 100. (2) a M _a X _b Si _{c B d} as a main component, the main component
On the other hand, it contains 0.01 to 1.0% by weight of Sn,
Made by cooling method, from the surface of the ribbon in the thickness direction of the ribbon
In the surface layer where the measured distance is in the range of 0.1 μm or less,
Sn concentration segregation whose width measured in the thickness direction is 0.03 μm or less
And the peak concentration of Sn in the segregation layer is
5 times higher than the Sn concentration in the
Amorphous alloy ribbon. Where M is F
e, at least one of Co, Ni, and X is Mo, Nb, T
a, W, Cr, V, Mn, at least one of Cu,
a: 60 to 90 (atomic%, the same applies hereinafter), b: more than 0 to 6,
c: 1 to 19, d: 7 to 20, a + b + c + d = 100
It is.

(3) The amorphous alloy ribbon after quenching is 100
3. The method for producing an amorphous alloy ribbon according to the above 1 or 2 , wherein the amorphous alloy ribbon is maintained at a temperature of 300 to 300 [deg.] C. for 0.5 to 1000 hours . That is, the amorphous alloy ribbon of the present invention is characterized in that a thin Sn segregation layer for suppressing crystallization is provided on the surface of the ribbon. Amorphous alloys crystallize when heated above the crystallization temperature. However, crystallization does not proceed simultaneously throughout the alloy, but rather starts at the surface of the ribbon. This case is described in General Electr by Fiedler.
ic Report No. 81, 81 CRD199
(Issued in 1981). In the case of a ribbon formed by the single-sided cooling method, crystallization is performed from a free surface (a surface opposite to a surface in contact with a cooling substrate). This is probably because the free surface has a lower cooling rate than the surface on the substrate side. The temperature at which crystallization begins, whether on the free surface or the substrate surface, is significantly lower than the crystallization temperature of the amorphous alloy. Analyzed the crystallization behavior of an Fe-Si-BC amorphous alloy using Moessbauer analysis, and found that the crystallization of the surface layer was lower than the normal bulk crystallization temperature determined by differential thermal analysis. Starting at a temperature as low as 50 ° C. (Journal o
f Non-Crystalline Solids
Vol. 69, P361 (issued in 1985).

[0008] As a result of the surface layer crystallizing at a lower temperature than the interior, amorphous alloys lose their intrinsic properties at temperatures much lower than the crystallization temperature. In order to prevent this, conventionally, a method of adding a few percent of an element for improving the thermal stability or changing the composition of the main component has been used. However, this method impairs required characteristics other than thermal stability, as described in the section of the prior art.

The amorphous alloy of the present invention has a Sn segregation layer formed on the surface to improve the thermal stability without impairing the required characteristics. A specific method for forming the surface segregation layer of Sn is to add a small amount of Sn to the main component. The necessary addition amount of Sn is as small as 0.01 to 1.0% by weight, preferably 0.1 to 0.5% by weight, so that the required characteristics of the main component are hardly impaired. Rather, it produces a secondary effect of significantly improving magnetic properties and corrosion resistance.

Next, the constitution of the amorphous alloy of the present invention will be described in detail. Main component also _{M a X b Si c B d} C e
It is displayed in _{M a X b Si c B d} . Where M is F
e, at least one of Co, Ni, and X is Mo, Nb, T
a, W, Cr, V, Mn, at least one of Cu,
a: 60 to 90 (atomic% or less), b: more than 0 to 6,
c: 1 to 19, d: 7 to 20, e: more than 0 to 4, a + b +
c + d (+ e) = 100.

[0011] Fe, Co, and Ni are 6 in accordance with required characteristics.
It is selected in the range of 0 to 90 atomic%. For example, in the case of a magnetic material requiring a high magnetic flux density, Fe is a main component, and if necessary, Co and Ni are added in a range of 1 to 15 atomic%.
Replace with When high magnetic permeability is required, Co is used as a main component, and Fe and Ni are substituted with Co in a range of 1 to 10 atomic%.

[0012] The element X is added for the purpose of improving characteristics and secondary effects. For example, increasing the bulk crystallization temperature,
The purpose is to improve corrosion resistance and mechanical properties. In the present invention, the X element is limited to a range of more than 0 to 6 atomic%. The upper limit is specified mainly from the viewpoint of improvement effect and economy. The metalloid elements Si and B are constituent elements indispensable for forming an amorphous phase. Depending on the type and amount of the above metal element, S
i: 1 to 19 (at.%), B: 7 to 20 (at.%). When Si and B are out of this range,
Amorphization becomes extremely difficult. C is for cooling board material
Improves the wettability between the commonly used Cu etc. and the molten metal,
It is added to form a ribbon having good properties. C to 0.
Effective even by containing as little as 01 atomic%
Appears. However, when the content exceeds 4 atomic%, thermal stability is low.
And the saturation magnetic flux density decreases. Therefore,
C: Specified in the range of more than 0 to 4 (atomic%).

The present invention features Sn having high crystallization resistance.
The segregation layer is 0.1 μm measured from the ribbon surface in the depth direction.
It is formed on the following surface layer. If formed inside, the excellent properties inherent to the alloy are impaired. The thickness of the segregation layer is set to 0.03 μm or less. If the thickness is larger than this, the excellent properties inherent in the alloy are also lost. Further, the amount of Sn segregation has a peak value at least 5 times, preferably at least 10 times, that of the bulk (inside the ribbon). If the peak value of the Sn segregation is less than 5 times the bulk (inside the ribbon), the resistance to crystallization will not be sufficiently exhibited. The state of the Sn segregation layer can be measured by various surface analysis methods. For example, it can be detected using glow discharge emission spectroscopy (GDS), Auger spectroscopy (AES), or secondary ion mass spectrometry (SIMS).

FIG. 1 shows the results of surface analysis in the thickness direction of the amorphous alloy of the present invention measured by GDS. FIG. 1 shows the free surface of an amorphous ribbon having a composition of Fe ₇₈ Si ₁₂ B ₁₀ (atomic%). There are two types of Sn segregation layers, (a) shows an example of a single type of Sn peak, and (b) shows an example of a plurality of types. (C) is a surface layer of a conventional material without Sn segregation. It can be seen that the distribution of the basic composition changes in response to the segregation of Sn. Especially Si
Shifts inward, the distribution of Fe becomes two steps. The mechanism by which the presence of the Sn segregation layer enhances the crystallization resistance is not clear at present, but it is presumed that not only the Sn segregation layer itself but also the existence state of the main component as described above contributes. .

The method of forming a Sn concentration segregation layer according to the present invention comprises the steps of:
It consists of quenching using a single-sided cooling method. The reason for defining the amount of Sn added as described above is as follows. Sn
If less than 0.01% by weight, a segregation layer sufficient to have crystallization resistance will not be formed, and if more than 1.0% by weight, the Sn concentration in the bulk will be too high, and the excellent properties inherent in the basic component will be obtained. Is lost. Sn in the above composition range
, The production of ribbons by the single-sided cooling method, one lot
, The concentration of Sn varies, and as a result, S
Area where the n concentration segregation layer is not specified in the present invention
There may be areas. In this case, 100
Hold at a temperature of ~ 300 ° C for 0.5-1000 hours
(Aging treatment) forms an effective Sn segregation layer
It is.

The single-side cooling method used in the present invention is a known single-roll quenching method, but a belt method, a centrifugal quenching method, or the like can also be used. An alloy having a predetermined basic composition to which Sn in the above range is heated to a temperature equal to or higher than the melting point, is melted, and is ejected onto a cooling substrate moving through a nozzle. As the nozzle, a slit nozzle, a multi-slit nozzle or a wrapped multi-hole nozzle can be used. The multi-slit nozzle is effective for producing a thick material having a thickness of 50 μm or more. The atmosphere for casting may be any of air, inert gas, and vacuum. The manufacturing method described above is applied to a ribbon or a foil-like fiber having a wide shape with respect to the plate thickness, but the present invention relates to a flake obtained by causing sprayed droplets to collide with a cooling substrate. It can also be applied to flakes or powders.

The quenched amorphous alloy of the present invention is heat-treated for some applications. The conventional heat treatment is performed at a temperature considerably lower than the crystallization temperature of the bulk of the alloy, but a higher temperature can be employed in the material of the present invention having excellent surface crystallization resistance. As a result, the residual strain is sufficiently released by the rapid cooling, so that the magnetic characteristics are significantly improved.

[0018]

Embodiments will be described below with reference to embodiments. Example 1 After subjecting a mother alloy obtained by adding Sn, 0.05, 0.1, 0.3 and 0.5% by weight to an alloy having a basic composition of Fe ₈₄ Si ₂ B ₁₄ (atomic%) to high frequency melting, Then, it was quenched with a Cu roll through a slit nozzle having a width of 0.6 mm to produce a long ribbon having a width of 25 mm. It was confirmed by X-ray diffraction that all of the prepared ribbons exhibited halo peculiar to amorphous. The surface of each ribbon was analyzed using the GDS method. Table 1 shows the state of segregation on the free surface of Sn. In any of the alloys, Sn segregates from the surface into a shallow layer of 0.02 μm or less, and the concentration of the peak is at least 10 times higher than that of the inside. The half width of the peak, that is, the thickness of the segregation layer is 0.003 μm to 0.01 μm in the case of a single peak, and the sum of the half widths is 0.01 μm to 0.02 μm in the case of two peaks.
m.

The above-mentioned amorphous ribbon of the present invention is prepared at 320 ° C. for 6 hours.
After magnetic field annealing in nitrogen for 0 minutes, the film was again examined by the X-ray diffraction method. The sample after annealing was subjected to magnetic measurement using a single plate tester. The results are also shown in Table 1. Both the core loss (W _13/50 ) at 50 Hz and 1.3 T and the magnetic permeability (Bl) at 10 e are excellent characteristics that can be used for the core of a power transformer.

On the other hand, for alloys prepared for comparison and having the same basic composition and to which Sn is not added, and alloys having Sn less than the range specified by the present invention, no Sn segregation layer was observed or the segregation was confirmed by GDS measurement. The amount was very small.
Further, crystallization of the free surface was observed by X-ray diffraction after annealing at 320 ° C. for 60 minutes. As shown in the comparative example of Table 1, the magnetic properties are also significantly inferior to the amorphous ribbon of the present invention having a Sn segregation layer.

Example 2 A ribbon was produced in the same manner as in Example 1 by using a mother alloy obtained by adding a predetermined amount of Sn to an alloy having the basic composition shown in Table 2.
Table 2 shows the state of the Sn segregation layer on the free surface of the as-cast ribbon. The aging treatment was performed on some alloys. The presence or absence of aging is described in the remarks column of Table 3 (continued from Table 2). These ribbons were heat-treated in a nitrogen atmosphere at a temperature 60 ° C. lower than the respective crystallization start temperatures (Tx) for 60 minutes. Table 3 shows the results. After annealing, the free surface of the ribbon was examined by X-ray, and it was found that each had a halo pattern and was not crystallized.

On the other hand, it was confirmed that the comparative material having the same basic composition and having no Sn segregation layer crystallized by annealing under the same conditions.

[0023]

[Table 1]

[0024]

[Table 2]

[0025]

[Table 3]

[0026]

As described above, the amorphous alloy ribbon having a surface segregation layer of Sn of the present invention has high resistance to crystallization. Due to this feature, a magnetic material can be heat-treated at a high temperature, and excellent magnetic properties can be obtained.
Further, since the generation of rust is suppressed, handling becomes easy, and the practical effect is extremely large.

[Brief description of the drawings]

FIG. 1 is a view showing a concentration distribution of a main element in a surface depth direction of an amorphous alloy ribbon of the present invention. However, (c) is a comparative example.

Continuation of the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical indication location C22C 45/04 C22C 45/04 C C22F 1/00 C22F 1/00 B H01F 1/153 H01F 1/14 C ( 72) Inventor Wataru Ohashi 1618 Ida, Nakahara-ku, Kawasaki-shi, Kanagawa Prefecture Nippon Steel Corporation Advanced Technology Research Laboratories (56) References JP-A-59-182938 (JP, A)

Claims (3)

(57) [Claims] [Claim 1] as a main component _{M a X b Si c B d} C e,
It contains 0.01 to 1.0% by weight of Sn with respect to the main component, and is produced by a single-sided cooling method .
Tables where the distance measured in the thickness direction is within 0.1 μm
In the surface layer, S having a width measured in the thickness direction of 0.03 μm or less
An n concentration segregation layer is formed, and the Sn peak concentration of the segregation layer is
An amorphous alloy ribbon having a degree of at least five times the Sn concentration in the bulk and having enhanced crystallization resistance. Here, M is at least one of Fe, Co and Ni, and X is M
at least one of o, Nb, Ta, W, Cr, V, Mn and Cu, a: 60 to 90 (atomic%, the same applies hereinafter), b:
Over 0 to 6, c: 1 to 19, d: 7 to 20, e: Over 0 to
4, a + b + c + d + e = 100. Wherein the main component _{M a X b Si c B d} , main
0.01 to 1.0% by weight of Sn
And produced by a single-sided cooling method.
Surface whose distance measured in the viewing direction is within 0.1 μm or less
In the layer, Sn whose width measured in the thickness direction is 0.03 μm or less is used.
Forming a concentration segregation layer, and Sn peak concentration of the segregation layer
Is at least 5 times the Sn concentration in the bulk,
Amorphous alloy ribbon characterized by enhanced properties. However,
M is at least one of Fe, Co, and Ni, and X is Mo, N
at least one of b, Ta, W, Cr, V, Mn, and Cu
A: 60 to 90 (atomic%, the same applies hereinafter), b: over 0 to
6, c: 1 to 19, d: 7 to 20, a + b + c + d = 1
00. 3. The quenched amorphous alloy ribbon is 100 to 30%.
0 claim 1 or 2 method for producing an amorphous alloy ribbon, wherein the holding 0.5 to 1000 hours at a temperature of ° C..