JPS60177936A - Thin strip consisting of fe-base amorphous alloy having large thickness - Google Patents

Abstract

PURPOSE:To manufacture a titled thin strip having a good surface of specific thickness and width or above by subjecting the unsolidified free surface side, on a cooling bare body, of the thin alloy strip drawn out of a paddle to pressurization by direct injection of gas, etc. thereby intensifying forced cooling and heat contact and increasing the solidifying rate. CONSTITUTION:A thin alloy strip drawn out of a paddle at a high speed is quickly cooled as it travels at an equal speed on a cooling bare body. The unsolidified free surface thereof is pressurized by the cooling gas injected directly thereto and the heat contact with the bare body is increased to increase the solidifying rate. The thickness of the thin strip consisting of the Fe amorphous alloy is made to >=45mum thinkness, >=20mm. width and <=0.5mum free surface Ra with respect to 0.8 cut-off value in surface roughness by such increase in the solidifying rate. The roll surface is also made to <=0.5mum Ra. The increase in the cooling method is executed by a method of increasing the pressure over the entire part of the atmosphere and exerting pressure to the paddle itself or superposing the 2nd paddle on the unsolidified thin strip emitted from the paddle and pressing the same.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a large Fe-based porous crystalline material produced by rapidly solidifying a metal (alloy) in a molten state on the surface of a moving cooling substrate. This relates to alloy ribbons.

(Prior Art) The basic methods for continuously producing thin ribbons by rapidly cooling metals (alloys) from a molten state include the centrifugal quenching method and the melt spinning method represented by the single roll method.

In this method, a jet of molten metal is ejected onto the inner or outer surface of a rotating metal drum to rapidly cool and solidify it, thereby creating a thin metal ribbon or wire.

According to this method, the cooling rate is extremely fast, so if the alloy composition is appropriately selected, an amorphous metal (alloy) having a structure similar to that of liquid metal can be obtained.

Amorphous metals (alloys) are metal materials that have attracted practical attention due to their unique properties, but the range of applications has been limited by the fact that only thin plates can be manufactured due to constraints on cooling rates.

Generally, the maximum thickness of an amorphous alloy depends on the alloy composition and the cooling capacity of the device. The composition dependence of the plate thickness that can be made amorphous has been investigated mainly for iron-based alloys, which are of practical importance, and Hagiw
Ara et al.'s report Sc1. Rep+ Re+.

Inat, Tohoku Univ, A-29(1
981), 351, the iron-based semimetallic alloys that are most likely to become amorphous are Fe-8I-B and Fe-P-
For C-based alloys, the maximum plate thickness is Fe75 for Fe-8i-B.
It is reported to be 250 μm for SljDB15.

However, this method takes special measures to reduce the rotation speed by suddenly applying a brake to the rotation of the cooling substrate (roll) in order to obtain a thick sample. It has also been revealed that thick amorphous ribbons can only be obtained under such unsteady conditions, without the ability to obtain solid materials. Therefore, Hagi
It is clear that the material obtained by the method of Wara et al. is not an industrially applicable material. Furthermore, there are disputes regarding the maximum plate thickness of 250 μm in this report. That is, the report of Luborsky et al. IEEE Trans, Magnatlcs+ MA
According to G-18 (1982) 1385, Fe-8i-B
The maximum plate thickness that can be obtained in a substantially completely amorphous alloy is 42 μm for Fe74Si1oB16, and it is stated that if the plate thickness becomes larger than this, an increase in coercive force is observed, which is thought to be due to the formation of fine crystals. Regarding the discrepancy in the results with Hagiwara et al., Luborsky et al. pointed out that Hagiwara I- used optical microscopy (100x magnification) to determine amorphization, and that microscopic microstructures that could not be detected with an optical microscope were used by Luborsky et al. It has been pointed out that even in crystals, it deteriorates properties such as magnetism.

If Luboraky et al.'s theory is correct, then Hag
The 250 μm thick amorphous material reported by Iwara et al. contains microcrystals that degrade the properties, although they are not observed with an optical microscope.

Also, even if Hagiwara et al.'s thick sample were completely amorphous, their experiments were conducted with a narrow sample, about 1 inch wide, and the same thickness cannot be guaranteed with a wider material. This is because in the case of a narrow material, the heat flow across the substrate is two-dimensional, whereas in the case of a wide material, the heat flow across the substrate is one-dimensional, and as a result, the cooling rate is significantly reduced.

By the way, among amorphous alloys, Fe-based alloys are inexpensive, have excellent properties, and are extremely useful materials from a practical standpoint. Even when used in transformer cores, which are considered useful, there are problems such as they can only be used in the form of wound cores. In any case, it has been difficult to industrially produce a thick and wide Fe-based amorphous alloy ribbon using current technology.

(Objective of the Invention) The present invention provides a thick and wide Fe-based amorphous alloy ribbon that could not be achieved with the prior art as described above.

(Structure and operation of the invention) The Fe-based amorphous alloy ribbon of the present invention is characterized by being wide and thicker than conventional ribbons. The plate thickness is at least 45 μm and the width is at least 20 μm.

The Fe-based amorphous alloy ribbon of the present invention further has a surface that is smoother than the roll surface, compared to a ribbon produced by the conventional single roll method.
Both free surfaces are smooth.

As shown in Table 1, the centerline average roughness Ra at a cutoff value of 0.8wn measured by the method prescribed in JIS BO2 old was (5) 0.5 μm or less for both the roll surface and the free surface. This value is the C-rule surface 0 of the conventional material.
．． This is a smaller and better value than 0.6 to 1.5 fim per surface of 6 to 1.3 μm.

Reflecting the large thickness and smooth surface, the amorphous alloy ribbon of the present invention has an extremely high space factor when laminated. While the space factor of the conventional material is 75-85, the amorphous alloy ribbon of the present invention has a space factor of 85-95.

Although the amorphous alloy ribbon of the present invention has a large thickness, its properties often deteriorate. The reason is that even if the material is thick, it remains substantially amorphous throughout the entire thickness and thus retains properties unique to amorphous materials. For example, regarding magnetism, Fe
ao, ss l b, 5Bi 2CI (at
%) of 25μm thick, 25mm wide amorphous alloy ribbon 50H
The magnetic flux density at z (hertz) and 10e (oersted) is 1.53 T (tesla), but the amorphous alloy ribbon of the present invention with the same composition and 65 μm thickness and 25 mm width is
It shows the same 1.53T at 50Hz and 10e, and it is clear that there is no deterioration.

Next, the method for producing the thick amorphous alloy ribbon of the present invention (6) Let's talk about.

The amorphous alloy ribbon of the present invention can be produced by the following means that essentially increase the cooling rate.

Molten metal ejected onto the surface of a moving cooling substrate as in the single roll method (or belt method) forms a puddle (hereinafter referred to as a puddle) on the substrate, and solidification progresses from the portion in contact with the substrate. A high solidification rate is required to obtain a large plate thickness. There is a limit to the thickness of the thin strip that can be produced using conventional methods such as increasing the ejection pressure, reducing the moving speed of the cooling substrate, and increasing the gap distance between the nozzle and the substrate (approximately 45 μm). Also, if you try to make the board thicker than that (if the width is more than 201 mm), the shape, surface quality, and characteristics will deteriorate. Therefore, in order to obtain a thick plate without impairing the shape or properties, it is necessary to take measures to essentially increase the solidification rate. In order to increase the solidification rate, the present inventors applied the following method to produce a thick and wide amorphous alloy ribbon.

The thick and wide amorphous alloy ribbon of the present invention is produced by a method that increases the cooling rate during solidification. ie by means of increasing the thermal contact between the alloy and the cooled substrate while the alloy drawn from the paddle is in an unsolidified state.

Specifically, gas pressure or the pressure of the molten metal flow jetted from the second and third nozzle openings is used.

There are two methods to use gas pressure. One is to apply pressure directly to the unsolidified free side of the alloy ribbon pulled out from the paddle by gas injection, and the other is to apply pressure directly to the unsolidified free side of the alloy ribbon pulled out from the paddle. This method increases the pressure of the atmosphere surrounding the entire unsolidified ribbon.

The former method appears to be similar to conventionally proposed methods, such as the method described in US Pat. No. 3,862,658, but is completely different in the following points. In the conventional method, a gas pressure or an auxiliary roll (or belt) is pressed against the completely solidified amorphous alloy ribbon pulled out from the paddle.

Therefore, it does not increase the solidification rate and it is not possible to produce a thick amorphous alloy ribbon.

The second method is to make the entire atmosphere high pressure, and since pressure is applied not only to the drawn amorphous alloy ribbon but also to the paddle itself, the solidification rate is even greater. Manufacture of the belt becomes easier.

As a method that does not utilize gas pressure, there is a method that utilizes the pressure of the molten metal flow according to the invention of the present inventor (Japanese Patent Application No. 1983).
-216287). In this method, a second nondle is superimposed on the amorphous alloy ribbon drawn from one nondle while it is still unsolidified, and the pressure applied by the second nondle allows the noncrystalline alloy ribbon to be bonded to the cooling substrate. The thermal contact increases and the solidification rate increases. By stacking paddles one after another in this manner, it is possible to produce a thick amorphous alloy ribbon corresponding to the amorphous critical thickness of the alloy under the increased cooling rate.

The amorphous alloy ribbon of the present invention is characterized not only by its large thickness but also by its excellent surface quality. As already mentioned, in order to obtain a thick plate, measures are taken to improve the thermal contact between the amorphous alloy ribbon and the cooling substrate (9), but this also reduces air bubbles that are drawn into the substrate surface. reduce the size and number of As a result, the substrate surface of the amorphous alloy ribbon has a smooth surface with fewer bubbles, which are characteristic of single-sided cooling methods such as a single roll method. The effect of improved thermal contact between the amorphous alloy ribbon and the cooling substrate is also reflected in the surface texture of the free surface side. - Since the non-uniformity of heat transfer within the grain is reduced, the solidification interface becomes flat, and as a result, the free surface of the drawn amorphous alloy ribbon also becomes smooth. When the surface of the thick and wide amorphous alloy ribbon of the present invention is measured using the JIS B12O3 method, the cutoff value is 0.8 mm, and the surface on the substrate side (in the case of the single roll method,
The Ra of the roll surface side is 02 to 0.5 μm, and the free surface is 0.
1 to 0.5 μm, and the substrate surface of the amorphous alloy ribbon produced by the conventional single-sided cooling method is 0.6 to 1.38 m1, and the free surface is 0.
．． It is clear that it is extremely smooth compared to 6-1.5 μm.

Since the amorphous alloy ribbon of the present invention is thick and has a smooth surface, it has an extremely high space factor when laminated. 750 g of the amorphous alloy ribbon of the present invention with an average thickness of 60 μm and a width of 25 mm (10 mm) was placed on a bobbin with an outer diameter of 40 mm.
The space factor was 91 when wound up with a tension of kQ. In contrast, the space factor of conventional material is 8 when the thickness is 30 μm.
0 to 85 is normal. When a material with a high space factor is used for a magnetic core or the like, it is practically advantageous because it can be miniaturized.

The amorphous alloy ribbon of the present invention has Fe as a main component, B,
One building for St, C, P, etc.'! l: An alloy containing two or more metals as metalloids, and Fe may be partially replaced with other metals depending on the required characteristics. In other words, when magnetic properties are required, Co
, may be replaced with one or two types of Ni. Mo and Nb to improve magnetic properties.

One or more types of Mn, Sn, one or more types of Mo, Cr, TilZr1VIHf, Ta, W to improve corrosion resistance, Mn+A to improve mechanical properties
t, Cu, Sn, etc. may be added. The content range for Fe is 40 to 82% (at4, the same applies hereinafter) (however, Fe
can be replaced with one or two of Co and Ni), B is 8 to 17 qb, Si is 1 to 15%, and C is 3%.
Hereinafter, other elements will be selected depending on the purpose within a total amount of 10 or less. Also, the total of all elements constituting the alloy is 1
00%.

When the amorphous alloy ribbon of the present invention is used, for example, as an iron core material, the preferred composition is FeaBbSicC4, and the range of each component is a-nea 7 to 82. b28～], 5, c
: 4~]-5, a: o~3.

Next, examples of the present invention will be shown.

Example I Using a single roll made of Cu, an alloy having the composition shown in Table 1 was rolled in a width of 2
A 5 mN amorphous alloy ribbon was cast. However, the nozzle has a triple slot-shaped opening (width d 0
．． 4 mm + length 7125 mm + spacing a1 mm)
The manufacturing conditions are: jet pressure 020~0,3
5 kg/cm2, roll peripheral speed 20-28 m/sec%
The test was carried out with a distance between the nozzle and the roll of 0.15 to 0.25 mm.

Table 1 shows the plate thickness, surface roughness, and space factor of the amorphous alloy ribbon of each composition.

Furthermore, Table 1 lists typical characteristics of conventional materials produced using the single roll method as comparative examples.

It is clear that the amorphous alloy ribbon of the present invention has a larger thickness, lower surface roughness, and higher space factor than conventional materials. Figure 2 (a) shows an example of the surface roughness profile of the amorphous alloy ribbon of the present invention (thickness: 62 μm) and the comparative material (thickness: 40 μm).
) to (d). (IL) is the free surface of the amorphous alloy ribbon of the present invention, (b) is the roll surface of the same as above, (C) is the free surface of the comparative material, and (d) is the roll surface of same as above.

Furthermore, the amorphous alloy of the present invention produced by the method of Example 1 has the following characteristics not found in conventional materials.

That is, the magnetic domain structure of the cast and unrolled amorphous alloy ribbon of alloy A1 in Table 1 is as shown in FIG. 3(a). Figure 3(b)
Compared to the as-cast magnetic domain structure of the conventional material shown in Figure 1, the amorphous alloy ribbon of the present invention has a completely different aspect. That is, while the conventional material exhibits a complicated labyrinth-like magnetic domain pattern, the amorphous alloy ribbon of the present invention consists of 180'ai sections already aligned in the length direction in the casting trench. This shows that the amount and distribution of strain inside the amorphous alloy ribbon are completely different.

The amorphous alloy ribbon of the present invention has a magnetic domain pattern (] as shown in FIG. 3(a).
As suggested by 3), various magnetic applications such as iron cores of high-frequency transformers can be considered even with casting.

FIGS. 4(a) and 4(b) compare the magnetic domain structures after annealing in a magnetic field. The amorphous alloy ribbon (a) of the present invention has a magnetic domain width several times larger than that of the conventional material (b). This is thought to be due to the smoothness of the surface, which has fewer surface defects that inhibit the movement of domain walls.

Example 2 Whistle 2 was produced using the same single roll, nozzle, and manufacturing conditions as Example 1.
An alloy having the composition shown in the table was cast into an amorphous alloy ribbon having a width of 25 mm. The plate thickness, surface roughness, and space factor of the amorphous alloy ribbon of each composition are shown in Table 2 along with comparative examples. It is clear that the amorphous alloy ribbon of the present invention has a larger thickness, smaller surface roughness, and higher space factor than conventional paulownia. Therefore, it can be used for various purposes.

(Effects of the Invention) As explained above, the Fe-based amorphous alloy ribbon of the present invention has a large plate thickness and a smooth surface, so that when it is used, for example, in the iron core of a transformer, it can be used as a conventional thin non-(14) quality alloy. Thin ribbon has many problems such as the efficiency of lamination work and the mechanical strength of the core, so it was thought that it was impossible to use it in the stacked core system, and it was impossible to use it in the form of a wound core. However, the amorphous alloy ribbon of the present invention It can be applied to laminated iron cores, and moreover, it can be applied to laminated iron cores [7
The space factor of the material can be greatly improved when the iron core is compacted.

Even when used for purposes other than cutting iron cores, the large plate thickness provides high mechanical strength, and the smooth -1 surface allows for use in a variety of applications, making it extremely effective.

(]5) -10ri- B: Magnetic flux density Ra at 50HzlOe: Cutoff value 0.8mi, measurement length 8m + space factor: outer diameter 40
The space factor when the width of 25+w+ is wrapped around the width of wφ. Calculated from the following formula R: Ring outer diameter r: Ring inner diameter W: Ribbon width ρ: Specific gravity (16) 1R1i- is approximately 700 gr O

[Brief explanation of the drawing]

FIG. 1 is a bottom view showing a nozzle for producing the amorphous alloy ribbon of the present invention, and FIGS. 2(a) to (d) are the amorphous alloy ribbon of the present invention ((a): free surface, (b) ): roll surface) and comparison material ((c
): free surface; (d): roll surface). The photographs showing the metal magnetic domain structure, FIGS. 4(a) and 4(b), are also photographs showing the metal magnetic domain structure of the free surface after annealing. (18) -1 and the a) (b) Figure 4 (a) (b) Procedural amendment (voluntary) ゛May 13, 1985 Mr. Manabu Shiga, Commissioner of the Patent Office■, Indication of the case Showa 1959 Patent Application No. 033335 2, Title of the invention: Fe-based amorphous alloy ribbon with large plate thickness 3, Relationship with the case of the person making the amendment 4th attorney for the patent applicant Address: 100 6, Description of the specification to be amended In Column 7 of the Detailed Description of the Invention, page 9, lines 9-10 of the Specification of Contents of the Amendment, ``while in the uncoagulated state'' is amended to ``before the coagulation is completed.'' (2)

Claims (2)

[Claims] (1) The plate thickness is 45 μm or more, the plate width is 20 mm or more,
A large Fe-based porous crystalline alloy ribbon manufactured by a single-sided cooling method. (2) The plate thickness is 45 μm or more, the plate width is 20 mm or more, and the surface roughness is measured according to the JIS-BO601 method and has a cutoff value of 0.8 mm.
is 0.5 μm or less, Ra of the roll surface is 0.5 μm or less, and a large Fe-based porous crystalline alloy ribbon is produced by a single-sided cooling method.