JP2579754B2 - Preform wire and method for producing preform sheet - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a method for producing a preform wire and a preform sheet for a fiber reinforced metal composite (FRM), and more particularly, to a method for producing fibers such as silicon carbide fibers in a melting tank. The present invention relates to a method for producing a preform wire and a preform sheet in which high-frequency electromagnetic vibration is applied from outside a melting tank when impregnating a metal or glass with a preform.

[Prior art and its problems] Conventionally, a fiber-reinforced metal composite material in which a fiber material such as silicon carbide fiber is impregnated with a metal such as aluminum is excellent in various properties such as toughness, light weight or flexibility, and , The advantages of both metals and textiles,
It is expected to be widely used for various materials such as aircraft, rockets, and spacecraft.

In order to produce such a fiber reinforced metal composite,
First, a preform material such as a wire or sheet of a composite material precursor (preform) is manufactured, and molded articles of various shapes are manufactured from the preform material. Various methods for producing such a preform material have been proposed. For example,
There is known a method of spraying metal fine particles or metal vapor onto a fiber bundle, such as plasma jet, metallikon or vacuum vapor deposition, to attach metal to the fiber surface to produce a fiber reinforced metal composite material or a preform material which is a precursor thereof. ing. However, in these methods, since metal fine particles or metal vapor is blown straight, the metal does not sufficiently penetrate into the inside of the fiber bundle, and a satisfactory strength and elasticity cannot be obtained. .

As another method, a method has been proposed in which a fiber bundle is immersed in a molten metal tank and a molten metal that applies ultrasonic vibrations to the molten metal tank penetrates into the fiber bundle. In this method, the fiber bundle is opened by the ultrasonic vibration, and the metal penetrates well into the inside of the fiber bundle in order to discharge the air inside. Therefore, it is difficult to impart desired strength and elasticity to the fiber-reinforced metal composite. In addition, when using the ultrasonic vibration device, cracks occur from the portion of the hole for the cooling water of the horn of the vibrator with use time,
There is a problem that vibration is not transmitted to the tip horn immersed in the molten metal bath.

To solve such a problem, Japanese Patent Application Laid-Open No.
The invention described in Japanese Patent Publication No. 167 is proposed. According to the present invention, a metal such as aluminum is sprayed or vapor-deposited on a silicon carbide fiber bundle prepared in advance, and then impregnated into a molten metal tank vibrated by an ultrasonic vibrator, To protect the ultrasonic vibrator from high temperatures, provide a hole for cooling water in the portion corresponding to the half-wavelength node of the ultrasonic wave above the vibrator horn that is not immersed in the molten metal bath, or use water cooling. It is characterized in that a jacket is provided, which prevents cracks from occurring in the horn, and provides a horn of stable quality for a long time. However, this method has the following disadvantages.

1. Since the ultrasonic vibrator is in the metal tank, the metal of the vibrator dissolves, whereby the matrix metal component of the preform material fluctuates, and a uniform preform material cannot be obtained.

2.Because the ultrasonic vibrator is melted, it must be constantly adjusted to optimize the vibration frequency (19-20KHz) to uniformly cover and fill the matrix metal of the preform material.

3. The type of matrix metal or the material of the ultrasonic vibrator is limited because the ultrasonic vibrator is melted and damaged.

4. Cooling water for cooling the ultrasonic vibrator may leak into the high-temperature bath, which is dangerous.

As described above, a method for producing a fiber-reinforced metal composite excellent in high quality, mass productivity, maintainability, and safety has not yet been obtained.

[Object of the Invention] The present invention has been made in view of the above problems, and is a fiber-reinforced metal composite material excellent in high quality, mass productivity, maintainability, and safety, particularly a metal such as aluminum and silicon carbide. It is an object of the present invention to provide a method for producing a preform wire or preform sheet for FRM comprising a fiber such as a system fiber.

[Means and Actions for Solving the Problems] In order to achieve the above object, in the method for producing a preform wire and a preform sheet of the present invention, metal or glass melted in a melting tank is continuously reduced. When impregnating the supplied fiber bundle, high frequency vibration is applied to the fibers in the molten metal without bringing the induction coil for applying high frequency vibration into contact with the molten metal or glass.

In this case, it is preferable that the high frequency vibration is an electromagnetic vibration of 10 kHz to 500 kHz.

In the present invention, the fiber is first immersed in a melting tank, and the fiber is impregnated with metal or glass. As the fibers used here, carbon fibers, boron fibers, silicon carbide fibers, silicon nitride fibers, alumina fibers, silica-alumina fibers and the like are used.

Further, in the present invention, before impregnating the fiber with the metal or glass, a step of spraying or vapor-depositing a metal on the fiber bundle may be provided in advance to prevent the fiber bundle from being disturbed by the high-frequency treatment. As this step, any means can be employed as long as it fixes each fiber in parallel.

As described above, in the present invention, fibers are impregnated with molten metal or glass in a melting tank. As the metal used here, aluminum, magnesium, titanium, antimony, zinc, tin, lead, copper, silicon and the like are appropriately selected, and an alloy thereof may be used. Glass having any composition is used.

Next, high-frequency electromagnetic vibration is applied to the fiber bundle immersed in the melting tank from outside the melting tank by a high-frequency electromagnetic induction device.
In addition, the vibration by the high-frequency electromagnetic induction device is controlled by appropriately setting the frequency, and generally, the frequency is 10 KHz.
A frequency of ~ 500 KHz is used.

The fiber bundle that has been subjected to the high-frequency electromagnetic induction treatment in a state where the fibers are aligned in advance in this manner has a small amount of voids due to sufficient penetration of metal or glass between the fibers.

In the present invention, it is necessary that the metal previously adhered to the surface of the fiber bundle be melted at a point immediately below the induction coil provided outside the melting tank. However, even if the high-frequency electromagnetic induction treatment is performed, metal or glass cannot be sufficiently penetrated into the fiber bundle. Taking this into consideration, the bath temperature of the melting tank is preferably about 20 to 100 ° C. higher than the melting temperature of the metal or glass. The degree is preferred.
The threading speed of the fiber bundle in the tank is preferably 0.5 to 20 m / min. If the speed is less than 0.5 m / min, the fiber strength is degraded due to the reaction between the metal or glass and the preform wire, and the productivity is undesirably lowered. On the other hand, if it is higher than 20 m / min, productivity is improved, but fiber opening becomes insufficient, so that impregnation failure of metal or glass occurs, which is not preferable.

The preform wire or preform sheet for FRM obtained in this manner is such that metal or glass sufficiently penetrates between the fibers, and that no void is obtained, and is lightweight,
In addition, properties such as strength and elasticity are excellent.

 Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a process schematic diagram showing one embodiment of the method for producing a preform wire for FRM of the present invention.

In FIG. 1, a molten fiber such as aluminum is sprayed by a metal spraying device 3 such as a plasma jet or a metallikon on a fiber bundle 2 which is expanded and aligned by a fiber bundle alignment device 1, and The parallelism of each fiber is fixed.

The fiber bundle 2 to which the metal adheres is introduced into a melting tank 6 filled with a molten metal such as aluminum or glass 5 via guide rolls 4a and 4b, and impregnated.

The molten metal or glass 5 is vibrated by a high-frequency electromagnetic induction device 7. This high-frequency electromagnetic induction device 7 includes a high-frequency oscillator 8 and an induction coil 9,
The induction coil 9 is provided on the outer upper surface of the molten metal or glass tank 6, and applies electromagnetic vibration to the molten metal or glass 5 through the induction coil 9 by a signal from the high-frequency oscillator 8. By this high frequency electromagnetic vibration, metal or glass can be sufficiently vibrated between the fibers.

The fiber bundle 2 impregnated with metal or glass is continuously drawn out through guide rolls 4c and 4d, a slit 10 or a die to give a desired shape, and excess metal or glass is squeezed out to obtain a predetermined fiber volume. The preform wire has a content (Vf) and is wound by, for example, the winding device 11. In the present invention, a preform wire has been described, but it goes without saying that the present invention is also applicable to a preform sheet or a preform tape.

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

Example 1 According to the process of FIG. 1, a silicon carbide fiber having a tensile strength of 300 kg / mm ² (trade name: Nicalon, made of 500 fiber bundles)
After aligning the bundle (manufactured by Nippon Carbon Co., Ltd.), aluminum was sprayed with a plasma jet to adhere the aluminum to the surface of the silicon carbide fiber bundle. Next, the silicon carbide fiber bundle to which aluminum was adhered was continuously passed through a guide roll in an aluminum bath at 700 ° C. and subjected to high-frequency electromagnetic dielectric treatment. At this time, the frequency of the high-frequency electromagnetic induction device is about 30 KHz, and the distance between the induction coil and the aluminum tank is 0.
~ 20 mm, preferably 5 mm or less, the immersion time of the silicon carbide fiber bundle in the tank is 50 seconds or less, preferably 10 seconds or less, and the threading speed through the slit is about 20 m / min, preferably 10 m / min or less. Performed in

This aluminum-containing silicon carbide fiber bundle was passed through a slit and a guide roll to obtain a desired shape, and excess aluminum was squeezed out and wound up by a winding device to obtain an aluminum preform wire for FRM. The fiber volume content of the aluminum preform wire for FRM was 30% by volume, the metal permeated sufficiently between the fibers, and no void was observed. In addition, the tensile strength was 90 kg / mm ^2, which was the same as the theoretical value, and it was demonstrated that there was no disorder in the fiber arrangement. In order to examine the strength of the silicon carbide fiber bundle of the aluminum preform wire for FRM, the tensile strength of the silicon carbide fiber bundle obtained by chemically dissolving and removing aluminum of the obtained wire was measured. No difference from the previous fiber strength was observed, and it was confirmed that carbonization of the fiber strength due to the reaction between the metal and the fiber did not occur.

Example 2 Alumina fiber having a tensile strength of 200 kg / mm ² (Al ₂
A preform wire for FRM was prepared in the same manner as in Example 1 except that O ₃ ) was used. As a result, the fiber volume content was 30% by volume, the metal permeated sufficiently between the fibers, and no void was observed. Further, the tensile strength was 60 kg / mm ² which was the same as the theoretical value.

Comparative Example 1 FRM was performed in the same manner as in Example 1 except that an ultrasonic oscillator was used instead of the high-frequency electromagnetic dielectric device.
A preform wire was prepared. As a result, the fiber volume content was 30% by volume, and the tensile strength was 60 kg / mm ² . However, with the lapse of time after the start of the production, the deterioration of the strength by 30% or more compared to Example 1 was observed due to the incorporation of Fe and the like, and the continuous operation was possible only for 2 to 3 hours due to the dissolution loss of the ultrasonic transducer. Did not.

Comparative Example 2 The same silicon carbide fiber as in Example 1 was impregnated with a metal by a pressure impregnation method (autoclave method) to prepare a preform wire for FRM. As a result, the fiber volume content is
The content was 30% by volume, and the tensile strength was 40 kg / mm ² . Since the contact time with the molten metal was long, the strength was deteriorated due to the reaction between the metal and the yarn, and the strength was less than half that of Example 1.

[Effects of the Invention] As described above, the present invention provides high-frequency vibration to a metal or glass bath when impregnating a continuously supplied fiber bundle with metal or glass melted in a melting tank. Since the high-frequency vibration is applied to the fibers in the bath without contacting the induction coil for application, the following effects are obtained.

Since the tank and the induction coil are not in contact, 1. A uniform preform material can be obtained without impurity metals melting.

2. Continuous operation is easy and high productivity.

3. Easy maintenance.

4. The type of the matrix metal or the material of the ultrasonic transducer is not limited.

5. High safety because the induction coil is covered with heat-resistant insulation such as Nicalon.

 In addition, since the high-frequency electromagnetic induction device is adopted, 6. the vibration frequency is not limited.

7. We can produce not only metal but also glass preform material. At this time, the glass matrix generates heat by itself and can prevent a drop in hot water temperature.

[Brief description of the drawings]

FIG. 1 is a process schematic diagram showing one embodiment of a method for producing an FRM preform wire according to the present invention. 1: Alignment device, 2: Silicon carbide fiber bundle, 3: Metal spraying device, 5: Molten metal or glass, 6: Melting tank 7: High frequency electromagnetic induction device, 8: High frequency oscillator, 9: Induction coil.

Claims (5)

(57) [Claims] When a metal or glass melted in a melting tank is impregnated into a continuously supplied fiber bundle, an induction coil for applying a high-frequency vibration is brought into contact with the molten metal or glass. A method for producing a preform wire and a preform sheet, wherein high-frequency vibration is applied to fibers in the molten metal. 2. The method according to claim 1, wherein said high frequency vibration is an electromagnetic vibration of 10 kHz to 500 kHz. 3. The method according to claim 1, wherein the fibers before impregnating with the metal or glass are spread and aligned, and then the metal is sprayed or vapor-deposited. 4. The method according to claim 1, wherein said fibers are carbon fibers, boron fibers, silicon carbide fibers, silicon nitride fibers, alumina fibers, silica fibers.
The method according to any one of claims 1 to 3, wherein the method is selected from alumina fibers. 5. The method according to claim 1, wherein the molten metal is aluminum, magnesium, silicon, titanium, antimony, zinc, tin, lead,
The method according to any one of claims 1 to 4, wherein the method is selected from copper or an alloy thereof.