JP3262939B2 - Method for producing irregular-shaped ribbon and nozzle for production - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin ribbon having a thickness distribution in the width direction of a thin ribbon by a rapid solidification method, that is, a thin metal or alloy having a so-called irregular cross section (hereinafter simply referred to as "metal"). The present invention relates to a band manufacturing method and a manufacturing nozzle.

[0002]

2. Description of the Related Art As one of the methods for producing a wide metal ribbon by a rapid solidification method, there is an invention described in Japanese Patent Application Laid-Open No. 53-133,531. In this method, a circular perforated nozzle is ejected and collided with the surface of a moving cooling substrate (usually, the outer circumference or inner circumference of a rotating roll or a drum), and the molten metal is spread on the substrate to integrate adjacent molten metals. , To manufacture wide metal ribbons.

[0003] Although not disclosed in the above-mentioned publication, this method is capable of forming not only a wide ribbon but also a thin wire depending on the control of the diameter and interval of the nozzle holes, the ejection pressure, the interval between the nozzle and the substrate, the substrate moving speed, and the like. It is also possible to manufacture many pieces. Therefore, the present inventors have tried various studies on the possibility of producing a deformed cross-section ribbon using this technique, but the overlap of the molten metal is insufficient and a part that is transparently formed or a width is formed. Only thin ribbons having no regularity in shape could be obtained due to poor synchronization of thickness in the direction.

The present inventors have already proposed a new casting method in Japanese Patent Application Laid-Open No. 63-149053 in order to eliminate such a conventional problem. This conventional method is a method of manufacturing a ribbon with a modified cross section using a nozzle 3 having a rectangular shape of each opening 2 as shown in FIG. 5, and a single-roll rapid solidification ribbon manufacturing apparatus shown in FIG. In the method, a nozzle 3 as shown in FIG. 5 is provided below the crucible 8, and the molten metal 6 melted by the heating device 7 is jetted onto the surface of the cooling roll 4 rotating at a high speed, thereby forming a ribbon with a deformed cross section. is there.
That is, this method uses a nozzle having a plurality of rectangular openings arranged in the width direction of the cooling substrate, and cools a pool of molten metal (hereinafter referred to as a “paddle”) formed between each opening and the cooling substrate. This is a method of obtaining an irregularly shaped cross-section ribbon by integrating it in a direction perpendicular to the substrate movement direction and forming a ribbon whose plate thickness is larger at a position corresponding to the nozzle opening than at a position corresponding to the space between the nozzle openings. .

[0005]

However, in order to stably produce a ribbon having an irregular cross-section by using the method described in JP-A-63-149053, it is necessary to further improve the following points. Was. In other words, a dent-like defect (hereinafter, referred to as “the defect”) along the cooling substrate moving direction
Occasionally, “streak defects” occurred. This streak defect is generated at a position corresponding to the space between the openings of the nozzles to be used, but is generated by preferentially involving the ambient gas at the joint of the individual paddles described above.

Hereinafter, a method of forming the streak defect will be described. FIG. 6 is a single-roll rapid solidification manufacturing apparatus, and FIG. 7 is a schematic diagram in which the behavior of a molten sample in the vicinity of a nozzle and a roll surface of this apparatus is enlarged. When the molten sample is jetted to the roll surface via the nozzle 3, the above-mentioned paddle 9 is formed between the nozzle opening and the roll surface. Immediately below this paddle, a ribbon 5 forms on the roll surface. FIG.
FIG. 3 is a schematic view of a state of casting as viewed from the side, where a paddle indicates one of a plurality of nozzle openings and a paddle formed on a roll surface.

[0007] Fig. 8 is a schematic view showing the state of the casting as seen through from above. In FIG. 8, the individual nozzle openings 2 are indicated by dotted lines. An integrated paddle 9 is formed around these openings, and the ribbon 5 is formed immediately below the paddle 9. The profile of the integrated paddle in the rear direction with respect to the roll rotation direction is almost straight, but sometimes it is not completely straight between the nozzle openings, and a slight dent is formed.
Is formed. When such a dent 10 is formed,
At this point, the atmosphere gas brought by the moving roll is preferentially entangled between the paddle and the roll surface, and the stripe defect 11 is formed on the thin roll surface. Such streak-like defects are not preferable because, for example, when they are formed into a magnetic shield material or a floor material, or further into a pipe shape and used as a heat dissipation or absorption material, the strength is deteriorated.

An object of the present invention is to provide a method and a nozzle for manufacturing a ribbon having a good cross section, which suppresses the occurrence of streak defects which have been an obstacle to the production of such a ribbon having a deformed cross section. The purpose is.

[0009]

SUMMARY OF THE INVENTION The present invention has the following constitution as its gist. (1) A plurality of openings provided with their long sides parallel to the direction of movement of the cooling substrate are arranged at right angles to the direction of movement of the cooling substrate. A nozzle provided with a depression having a constant depth over the entire opening and the opening interval is provided opposite to the cooling substrate, and the molten metal is jetted from the nozzle to the surface of the cooling substrate to be rapidly solidified. process for producing a modified cross-section ribbons (2) the depth d ₀ of the recess is provided on the side facing the cooling substrate of the nozzle 0.05
mm or more, from the length d ₁ and the rear end of the cooling substrate moving forward end of the plurality of openings of the nozzle upper length d ₂ are both less than 3mm, further the outermost ends of the plurality of openings of the nozzle upper opening length d ₃ and d ₄ from an outer end of a method for producing a modified cross-section ribbon according to the above (1), characterized in that both at 1mm or less, (3) the individual opening of the nozzle The length a in the cooling substrate movement direction is 1 to 20 mm, and the length b in the direction perpendicular to the cooling substrate movement direction is 0.2 to 5.0 m.
m, interval c between individual openings is 0.2 to 2.0 mm and a> b
Becomes a rectangular shape, and the depth d ₀ of the recess is provided only on the side of cooling the substrate and the counter is 0.05mm or more, the length of the cooling substrate moving forward end of the plurality of openings of the nozzle upper d ₁ and after The length d ₂ from the end is 3 mm or less, and the lengths d ₃ and d ₄ from the outer ends of the openings at the both ends of the plurality of openings at the top of the nozzle are all 1 mm or less. Nozzle for manufacturing specially shaped ribbons.

Hereinafter, the present invention will be described in detail. First,
FIG. 1 schematically shows the nozzle of the present invention. FIG. 1B is a view of the nozzle viewed from the side. When the nozzle is actually used for casting, the cooling substrate is placed below the nozzle in FIG. FIGS. 1A and 1C are views seen from above and below a nozzle, respectively. The nozzle of the present invention is characterized in that it has a depression 1 only on the side of the nozzle 3 facing the cooling substrate, as can be seen from FIG. By using a nozzle having such depressions to blow molten metal onto the surface of the moving cooling substrate and cast the molten metal, it is possible to produce a strip having a deformed cross section free from streak defects.

The reason why the use of the nozzle of the present invention prevents the generation of streak defects on the roll surface of the irregularly shaped ribbon is as follows.
It is considered as follows. That is, the molten sample ejected from the plurality of openings 2 in the upper part of the nozzle is connected to each other in the direction perpendicular to the cooling substrate movement direction at the depression 1 provided in the lower part of the nozzle, and the integration of the paddles easily occurs. Since the place where the ambient gas is preferentially caught in the integrated paddle no longer exists, streak defects are not generated. Although the reason will be described later, the plurality of upper openings and the lower depression need to be integrally provided as a nozzle member.

The reason why the size of the depression 1 is limited to the numerical value as described above will be described below. That is, the depth d _{0 of the} depression shown in FIG. 1B is set to 0.05 mm or more. When the value of d ₀ is less than 0.05 mm, almost no effect of suppressing the generation of streak defects is recognized. It depends. That is, as shown in FIG. 2, the value of _{d 0} is the incidence of streaky defects is higher than 10% even more than 20% is less than 0.05 mm. This is because the value is less than 0.05mm of d _0, the individual paddles forming the plurality of openings of the nozzle upper be provided a recess in the bottom nozzle are integrated, but preferentially at the connected parts of these individual paddles This is because the atmosphere gas is easily involved. Furthermore, as can be seen from FIG. 2, when the value of d ₀ is 0.5 mm or more, there is no streak defect. Therefore, the value of d ₀ is preferably 0.5 mm or more.

When the value of d ₀ reaches the thickness of the nozzle, it becomes impossible to manufacture a ribbon having an irregular cross section. Therefore, it is needless to say that the value of d ₀ is less than the thickness of the nozzle to be used. In the present invention, the thickness of the nozzle is not particularly defined, but if the thickness of the nozzle is too large, it takes time and effort to process the nozzle opening and preheat the nozzle before casting, so the thickness of the nozzle is made too thick. Is not preferred. The thickness of the nozzle is preferably about 20 mm or less. On the other hand, the value of d ₀ is preferably set to a value several mm smaller than the thickness of the nozzle at the maximum, taking into account the strength of the plurality of openings above the nozzle.

Next, the length d ₁ from the front end and the length d ₂ from the rear end of the plurality of openings above the nozzle in the direction of movement of the cooling substrate are each 3 mm or less as the length of the depression 1 in the direction of movement of the cooling substrate. The reason for limiting is as follows. First, Here, the "length from the length d ₁ and the rear end of the cooling substrate moving forward end of the plurality of openings of the nozzle upper d _2"
Is the length of d ₁ and d ₂ shown in FIG. 1 (c), respectively. The range of the values of d ₁ and d ₂ is 3 mm.
The reason for this is that, as shown in FIG. 3, when the length exceeds 3 mm, the incidence of streak defects increases to 20% or more.
Also, when the values of d ₁ and d ₂ are set to 3 mm or more, it is considered that this is the same as no longer providing a depression under the nozzle. That is, the ambient gas is preferentially involved at the joint of the individual paddles of the integrated paddle, so that streak defects are generated. Note that d
₁ and the value of d ₂ is also the same value as long as it is within this range, or may be different values.

Further, the length d ₃ , d from the outer end of the uppermost end of the plurality of openings in the upper portion of the nozzle is defined as the length of the depression 1 on the lower surface of the nozzle in the direction perpendicular to the direction of movement of the cooling substrate.
₄ was limited to 1 mm or less. The “differences d ₃ , d _{4 from} the outermost openings at the upper end of the plurality of openings at the top of the nozzle” are the lengths of d ₃ , d ₄ shown in FIG. Each of the values of d ₃ and d ₄ is set to 1
mm or less, if both are more than 1 mm,
This is because the plate thickness is reduced at both edges of the obtained ribbon. It is preferable that the values of d ₃ and d _{4 be} the same within this range.

The size of the recess 1 may be appropriately selected within the above range according to other casting conditions. It should be noted that optimal combinations of values regarding the dimensions of the nozzles actually used are specifically shown in the embodiments.

The nozzle of the present invention must not have an upper portion having a plurality of openings and a lower portion having a rectangular hole as shown in FIG. During actual casting, the nozzle is maintained at a high temperature, but at this time, the nozzle is easily deformed by thermal expansion. As shown in FIG. 4, when the two nozzles are overlapped with each other, the upper portion is hardly deformed due to thermal expansion, but the lower rectangular hole becomes narrower at the center in the longitudinal direction,
Or, it may become wider, which may hinder the connection with the upper openings.

The parameters defining the shape of the plurality of openings in the upper portion of the nozzle are the length a of each opening 2 in the direction of movement of the cooling substrate, the length b in the direction perpendicular to the direction of movement of the cooling substrate, and each opening shown in FIG. Is an interval c.

The range of the size of each parameter will be described. A is 1 to 20 mm, preferably 1 to 10 mm
Range. b is in the range of 0.2 to 5.0 mm, preferably in the range of 0.2 to 2.0 mm. C is in the range of 0.2 to 2.0 mm. What is important here is that the shape of the opening is a> b. By setting a> b, the molten metal ejected from the individual openings by overcoming the surface tension of the molten metal is integrated, and it becomes possible to produce irregularly shaped ribbons having different thicknesses regularly in the width direction of the sheet. .

The range of the magnitude of each parameter will be described below. When the value of a is less than 1 mm, it is difficult to stably integrate the molten metal from the individual openings even if a considerably large ejection pressure is used. On the other hand, the value of a is 20
If it exceeds mm, the cooling becomes insufficient with respect to the flow rate of the molten metal, and it becomes difficult to produce a ribbon having a good shape.

The value of b is set so that a> b by the value of a. However, if the value of b exceeds 5.0 mm, the molten metal can be stably supplied from each opening even if the value of a is increased. It was difficult to integrate. The lower limit of the range of the value of b is set because it is difficult to make the opening smaller than 0.2 mm in processing the opening. c is the above-mentioned a and b in order to integrate the molten metal spouted from each opening and form a thin ribbon of irregular cross section.
An important parameter as well. The value of c is 2.0 m
If it exceeds m, it is difficult to stably integrate the molten metal from the individual openings even if a considerably large ejection pressure is used. As in the case of b, the lower limit of the value of c is limited by the difficulty in processing the opening.

A basic manufacturing apparatus employed in the method of the present invention is a so-called liquid quenching apparatus which jets a molten metal onto a cooling substrate through a nozzle and rapidly solidifies the molten metal by thermal contact. It is a single roll device. Of course,
Centrifugal quenching devices using the inner wall of the drum, devices using endless belts, improved versions of these, e.g. with auxiliary rolls, roll surface temperature control, or under reduced pressure or in vacuum or in inert gas Includes casting.

Next, the casting conditions employed in the method of the present invention and specific casting operations will be described. The ejection pressure of the molten metal is 0.01 to 3 kg / cm ² , and the rotation speed (surface speed) of the roll is in the range of 5 to 60 m / sec. These conditions select optimal values in accordance with the target sheet pressure of the ribbon and other manufacturing conditions. As a casting operation, an optimal gap position between the nozzle and the roll is set in advance of the start of melting, assuming the time of casting, and then the crucible is once moved into a work coil for melting the metal, and then the metal is melted. Then, after the melting, the rotation of the roll and the ejection pressure are set, the crucible is returned to the preset optimum interval with the roll, and casting is started. For this reason, the position of the work coil is preferably set to a position slightly away from the roll surface.

[0024]

EXAMPLES The present invention will be further described below with reference to examples. Using the various nozzles shown in Table 1, a ribbon with an irregular cross section was produced by a single roll ribbon production apparatus in the atmosphere. Charge No. Nos. 1 to 14 represent the present invention, and charge Nos. 15 ~
Reference numeral 18 is a comparative example. The cooling roll used is made of copper,
The diameter is 300 mm and the width is 50 mm. The metal melting method is high frequency induction. Other casting conditions other than those shown in Table 1 are as follows. Melting component: Fe-Si _6.5 -B ₁₂ -C ₁ (amorphous alloy) Weight of molten metal: 100 g Crucible, nozzle material: transparent quartz Opening shape above nozzle: distance between both ends of opening (L in FIG. 5) ): About 25 mm Number of openings above the nozzle: 23 Roll surface speed: 22 m / s Nozzle gap: 0.3 mm Ejection pressure: charge NO. 14 is 0.5 kg / cm ² , other charges are 0.3 kg / cm ²

[0025]

[Table 1]

As a result, a strip having a width of about 25 mm was obtained for each charge. When the free surface of the obtained ribbon was observed well, it was found to have a modified cross-sectional area in which the thickness was regularly changed in the width direction. For all the ribbons, the roll surface of the ribbons was examined for the presence of streak defects using a magnifying projector. Regarding the ribbon where streak defects were observed,
Measure its length, find the ratio to the overall length of the ribbon,
It was arranged as the streak defect occurrence rate. Table 1 shows the results. When the streak defect occurred in the width direction of the ribbon, the total length of all the streak defects was defined as the length of the generated streak defect.

The length, the maximum thickness, the average thickness and the width of the ribbon were measured for all the ribbons, and these data are also shown in Table 1. The maximum plate thickness is a value obtained by a micrometer, and the average plate thickness is a value calculated from the alloy density (7.26 g / cm ³ ), the plate width and the length.

As can be seen from Table 1, the rate of occurrence of streak defects was as low as less than 10% in all of the charged ribbons of the present invention, and a good irregular cross-sectional area was obtained. On the other hand, when the casting was performed under the conditions as shown in the comparative example, the occurrence rate of streak defects was as high as 10% or more for each charge.

[0029]

As described above, according to the present invention,
In a continuous liquid quenching method such as a single-roll method, by using a nozzle having a specified shape and size, an irregularly shaped ribbon having an excellent shape can be obtained. The deformed cross-section ribbon can be used as a magnetic shield material, for example, because a magnetic material having irregularities on the surface is superior in magnetic sealability to a flat surface ribbon. An amorphous ribbon having a wavy shape on one side is hard and has corrosion resistance, so that when it is used for a floor material or the like, the object slides well and is convenient for moving heavy objects. Furthermore, if it is formed into a pipe shape, the surface area can be increased, which is advantageous for heat dissipation and absorption.

According to the present invention, the streak defect which has been generated in the deformed cross-section ribbon can be suppressed, so that the strength of the deformed cross-section ribbon can be improved. Also, it is possible to improve the production yield of the product.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a nozzle according to a method of the present invention.

FIG. 2 is a diagram showing the relationship between the depth (d ₀ ) of a rectangular depression under a nozzle and the incidence rate of streak defects on the surface of a ribbon roll according to the method of the present invention.

FIG. 3 is a diagram showing the relationship between the length (d ₁ , d ₂ ) of the rectangular recess below the nozzle in the cooling substrate movement direction and the incidence rate of streak defects on the surface of the ribbon roll by the method of the present invention.

FIG. 4 is a schematic view showing an example in which an upper nozzle having a plurality of openings and a lower nozzle having a rectangular opening are not applicable to the present invention.

FIG. 5 is a schematic view of a conventional perforated nozzle for producing a modified cross-section ribbon.

FIG. 6 is a schematic view showing a single-roll rapid solidification ribbon manufacturing apparatus.

FIG. 7 is an enlarged schematic diagram illustrating a state of casting using a single-roll rapid solidification ribbon manufacturing apparatus, particularly formation of a paddle.

FIG. 8 is a schematic diagram illustrating the generation of streak-like defects when a conventional multi-aperture nozzle for awe-inspiring cross section is used.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Depression provided in the lower part of the nozzle 2 Opening provided in the upper part of the nozzle 3 Nozzle 4 Cooling roll 5 Thin strip 6 Molten metal 7 Heating device 8 Crucible 9 Integrated paddle 10 Indentation behind the paddle 11 Streak defect a Cooling of opening substrate moving direction length b cooling the substrate moving direction in a direction perpendicular between the length c of each opening interval L opening both outermost ends of the distance d ₀ of the nozzle bottom of the rectangular recess depth d ₁ multiple of nozzles upper The length of the opening from the front end in the cooling substrate movement direction d ₂ The length of the plurality of openings above the nozzle from the rear end in the cooling substrate movement direction d ₃ , d ₄ The outer end of the opening at the both ends of the plurality of openings above the nozzle ₄ Length from

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-149053 (JP, A) JP-A-6-269912 (JP, A) JP-A-63-112052 (JP, A) JP-A-58-1983 77746 (JP, A) JP-A-63-112053 (JP, A) JP-A-63-130248 (JP, A) JP-A-4-41056 (JP, A) JP-A-7-303945 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) B22D 11/06 360 B22D 11/06 380

Claims (3)

(57) [Claims] A plurality of openings provided so that long sides thereof are parallel to the direction of movement of the cooling substrate are arranged at right angles to the direction of movement of the cooling substrate.
A nozzle provided with a recess having a constant depth over at least the entire opening and the opening interval is provided to face the cooling substrate, and the molten metal is ejected from the nozzle onto the surface of the cooling substrate to be rapidly solidified. A method for producing an irregularly shaped ribbon. Wherein the depth d ₀ of the recess is provided on the side facing the cooling substrate of the nozzle, 0.05 mm or more, the length d ₁ and the rear end of the cooling substrate moving forward end of the plurality of openings of the nozzle upper length d ₂ from both 3mm or less, further, the length d ₃ and d ₄ from an outer end of the opening of the top ends of the plurality of openings of the nozzle upper, characterized in that both at 1mm or less The method for producing a ribbon having a modified cross section according to claim 1. 3. The length a of the individual opening of the nozzle in the cooling substrate movement direction is 1 to 20 mm, the length b in the direction perpendicular to the cooling substrate movement direction is 0.2 to 5.0 mm, and the individual opening is Is a rectangular shape in which the interval c is 0.2 to 2.0 mm and a> b, and the depth d _{0 of the} recess provided only on the side facing the cooling substrate.
Is 0.05 mm or more, the length d ₁ from the front end of the plurality of openings above the nozzle in the cooling substrate moving direction and the length d from the rear end in the cooling substrate movement direction.
₂ is 3 mm or less, and the lengths d ₃ and d ₄ from the outer ends of the openings at the both ends of the plurality of openings on the nozzle are all 1 mm or less. Nozzle for manufacturing ribbon.