JPH0347184B2 - - Google Patents

Description

Detailed Description of the Invention <Field of Industrial Application> The present invention is directed to a composite material having a matrix of synthetic resin and/or rubber and reinforced with at least one type of inorganic, organic or metal fiber, and alumina fiber. The present invention relates to a fiber-reinforced tubular or rod-shaped structure in which composite materials using as reinforcing materials are laminated and integrated, and a method for manufacturing the same.

<Conventional technology> In recent years, carbon fiber reinforced resins (CFRP) and glass fiber reinforced resins (GFRP ), fiber-reinforced resins (FRP) such as alumina fiber-reinforced resin (ALFRP) are widely used, and their fields of use are expanding further.

<Problems to be solved by the invention> In general, FRP has the following characteristics depending on the characteristics of its reinforcing fibers:
Each has its own unique strengths and weaknesses. for example
CFRP has the features of being lightweight, high strength, and high rigidity, but because it is electrically conductive, it cannot be used in applications that require insulation, and it also causes the problem of electrolytic corrosion when bonded with metal. Since it is black, it is impossible to color the FRP itself. GFRP
Compared to other FRPs, it is inexpensive, has insulating properties, and can be colored, but its rigidity is 1/3 that of CFRP, and its compressive strength and fatigue strength are also low. ALFRP is insulating, can be colored, has a stiffness comparable to CFRP, and has superior compressive strength, interlaminar shear strength, crushing strength, buckling strength, torsional strength, and impact strength, but is inferior to CFRP in tensile strength. , specific gravity is 2.5, CFRP
Bigger and heavier than 1.5. Aromatic polyamide fiber-reinforced resin is lightweight, has high tensile strength, and is insulating, but its rigidity is 1/2 to 2/3 that of CFRP and ALFRP, its compressive strength is low, and it cannot be colored.

In particular, CFRP is widely used in fishing rods and golf shafts due to its light weight, high strength, and high rigidity. However, such elongated objects have low strength against bending in the longitudinal direction, and it is not always possible to sufficiently effectively increase the crushing strength and torsional strength in the radial direction. Furthermore, GFRP and aromatic polyamide fiber-reinforced resins lack rigidity and cannot provide satisfactory performance.

An object of the present invention is to provide a fiber-reinforced structure and a method for producing the same, which improve the above-mentioned drawbacks.

<Means for solving the problems> The present invention consists of a fiber-reinforced composite material in which at least one type of fiber selected from organic, inorganic and metal fibers is used as a reinforcing material, and a synthetic resin and/or rubber is used as a matrix. In a rod-shaped or tubular structure, a composite material (hereinafter abbreviated as composite material A) made of reinforcing fibers containing at least 50% by volume of fibers with a fiber orientation angle of 0 to 20 degrees with respect to the longitudinal direction of the structure. ), and at least 72% by weight of Al ₂ O ₃ and 28% by weight of SiO ₂ on the inner and/or outer surfaces of the structure.
α-
A composite material reinforced with alumina fibers that does not substantially reflect Al ₂ O ₃ (hereinafter referred to as composite material B) has a structure in which the alumina fibers are A fiber-reinforced structure is provided, characterized in that composite materials arranged with fiber orientation angles of 90 degrees are laminated and integrated.

Furthermore, the second invention uses at least one type of fiber selected from organic, inorganic and metal fibers as a reinforcing material,
In the production of rod-shaped or tubular structures made of composite materials with a synthetic resin and/or rubber matrix, at least 50% by volume of fibers with a fiber orientation angle of 0 to 20 degrees with respect to the longitudinal direction of the structure are included. On the outer surface of the structure reinforced with fibers,
The reinforcing material is alumina fiber containing 72% by weight or more of Al ₂ O 3 and 28% by weight or less of SiO ₂ , _which does not substantially reflect α-Al ₂ O ₃ in its X-ray structure, and is reinforced with synthetic resin. and/or rubber impregnated width
A method for producing a fiber-reinforced structure is provided, which comprises wrapping a 0.5-10 mm tape-like prepreg at a fiber orientation angle of 20-90 degrees with respect to the length direction of the structure, and then heat-forming it.

The present invention was developed as a result of intensive studies to solve the above problems, by combining the reinforcing fibers in FRP with a specific orientation angle, and using the fibers with an orientation angle of 20 to 90 degrees with respect to the length direction as alumina fibers. Traditional
In addition, crushing strength is improved without impairing the physical properties of FRP.
It has been discovered that a structure with excellent properties such as buckling strength and torsional strength can be obtained.

The present invention will be explained in detail below.

The alumina fiber used in the present invention is
It is composed of 72% by weight or more of Al ₂ O ₃ and 28% by weight or less of SiO ₂ , and does not substantially show α-Al ₂ O ₃ reflection in its X-ray structure. Specifically, the composition has an alumina (Al ₂ O ₃ ) content of 72 to 100% by weight and a silica (SiO ₂ ) content of 0 to 28% by weight, preferably 2 to 25% by weight. In addition, the silica content may be lithium, beryllium, boron, sodium, magnesium, silicon, phosphorus, potassium, calcium, titanium, chromium, manganese, It may be replaced with one or more oxides of ytrium, zirconium, lanthanum, tungsten, and barium.

In addition, in the X-ray structure of the alumina fiber, α
- It is desirable that the alumina exhibits virtually no reflection, and the tensile strength and elastic modulus are each 200 kg/
It is preferable to have a value of mm ² , 25t/mm ² or more.

The above alumina fibers are, for example,
It can be produced by the methods described in JP-A No. 12736, JP-A No. 51-13768, and the like.

On the other hand, as the inorganic, organic, and metallic fibers (hereinafter abbreviated as fibers A) used in combination with the alumina fibers in the present invention, reinforcing fibers generally used for FRP can be used. Examples of inorganic fibers include carbon fiber, graphite fiber,
Boron fibers, silicon carbide fibers, alumina fibers, glass fibers, etc. Organic fibers include aromatic polyamide fibers, polyester fibers, nylon fibers, etc. Metal fibers include stainless steel fibers,
Examples include steel fibers. One or more of these may be used depending on the required performance.

Among the above-mentioned fibers, carbon fibers, glass fibers, polyamide fibers, polyester fibers, and nylon fibers are preferred from the viewpoint of improving effects, and carbon fibers are particularly preferred.

As these fibers, commercially available fibers can be used as they are. For example, carbon fibers such as Magnamite AS-4 and IM-6 (Sumika Harkinires Co., Ltd.)
microglass yarn (manufactured by Nippon Glass Fiber Co., Ltd.) as glass fiber, Kepler 49 (manufactured by DuPont) as aromatic polyamide fiber, Econol fiber (manufactured by Sumitomo Chemical Co., Ltd.) as polyester fiber, and Naslon (manufactured by Sumitomo Chemical Co., Ltd.) as stainless fiber. (manufactured by Nippon Seisen Co., Ltd.), etc.

The form of these fibers is preferably a continuous fiber sheet, strand, tow, or yarn, but it depends on the purpose as long as at least 50% by volume has an orientation angle of 0 to 20 degrees with respect to the length direction of the target structure. Short fibers such as chopped strands and whiskers, woven fabrics such as satin fabrics and plain weaves, and even three-dimensional woven fabrics may be used in combination.

The synthetic resins and rubbers used as the matrix in the present invention include epoxy resins, phenolic resins, alkyd resins, urea-formaldehyde resins, melamine-formaldehyde resins, unsaturated polyester resins, aromatic polyamide resins, polyamide-imide resins, and polyester-formaldehyde resins. Thermosetting resins such as imide resins, polyimide resins, polybenzothiazole resins, silicone resins, polyethylene, polypropylene, polymethyl methacrylate, polystyrene (including so-called high impact polyethylene), polyvinyl chloride,
ABS resin, styrene-acrylonitrile copolymer, polyamide (nylon 6, 6.6, 6.10,
6・11, 6・12, etc.), thermoplastic resins such as polyacetal, polysulfone, polycarbonate, polyphenylene oxide, polyethersulfone, polyetheretherketone, polybutadiene, polyisoprene, polychloroprene, styrene-butadiene copolymer ( SBR), acrylonitrile-butadiene copolymer (NBR) silicone rubber, and other synthetic rubbers and natural rubber.

Among these, epoxy resins, unsaturated polyesters, polysulfones, polyethersulfones, polyetheretherketones, and polyimides are preferred.

In the present invention, in order to maintain the bending strength and elastic modulus in the longitudinal direction of the fiber A in a tubular or rod-like structure,
It is necessary to make a composite material in which at least 50% by volume of the fibers are arranged at an angle of 0° to 20°.
Those with a fiber orientation angle of more than 20° and up to 90°
If it exceeds 50% by volume, the bending strength of the structure will be extremely poor and the deflection will be large, which will cause practical problems when used in fishing rods, golf shafts, etc.

On the other hand, composite material B is
Alumina fibers are arranged at an orientation angle of 20 to 90 degrees, preferably 45 to 90 degrees, and are laminated and integrated on the inner and/or outer surfaces of composite material A, but at least when laminated and integrated on the outer surface. This is preferable because it improves not only the various strengths of the structure but also the appearance and insulation properties.

The volume content of the fibers in the above structure may be determined depending on the purpose, but is usually 20 to 80% by volume, preferably 40 to 70% by volume, and the ratio of alumina fibers to fiber A is particularly limited. Although not, it is preferably 2:1 to 1:100, particularly preferably 1:1 to 1:10 in terms of volume.

The method for manufacturing the structure of the present invention will be described below.

Regarding the composite material part using the fiber 1 as a reinforcing material, a rod-shaped body or a tubular body can be manufactured by the known filament winding method, hand lay-up method, or resin transfer molding method, but it is preferably carried out by the following method. .

In the case of a tubular structure, a prepreg in which fibers B are impregnated with resin or rubber is wound around a tapered rod-shaped mandrel at an orientation angle of 0 to 20 degrees with respect to the length direction. In addition, in the case of a large structure, sheet-like prepregs may be attached so that the fiber orientation angle of 0 to 20 degrees with respect to the length direction accounts for 50% by volume or more. A continuous prepreg of alumina fibers is then twisted around the length at an orientation angle of 20 to 90 degrees, preferably 45 to 90 degrees.

This continuous prepreg may be a tape prepreg, tow prepreg, strand prepreg or yarn prepreg, but drawn tape prepreg and tow prepreg are particularly preferred. The width of the prepreg varies depending on the thickness and length of the intended structure, but is preferably in the range of 0.5 to 10 mm. In addition, the thickness of the prepreg is less than the width dimension, but in the case of tape-shaped prepreg, it is preferably 0.02 to 5.
mm, particularly preferably 0.02 to 0.3 mm. The number of windings is one to several layers, and is appropriately determined in consideration of the size, strength, etc. of the target structure.

After winding, it is heated and formed by a known method to obtain the desired structure. In addition to the tape wrapping method, heat forming methods include methods of directly heat forming, autoclave molding, etc., but the tape wrapping method is preferred.

In addition, the reinforced composite material portion of fiber A is preformed,
There is also a method of wrapping the prepreg of alumina fiber around it and then heat-forming it, but it is preferable to wrap the prepreg of alumina fiber around it before heat-forming the reinforced composite material portion of fiber B and then heat-forming it. Furthermore, by first winding an alumina fiber prepreg on a mandrel, a structure made of a composite material whose inner surface is reinforced with alumina fibers can be obtained.

In addition, for a rod-shaped structure, a reinforced composite of rod-shaped fibers A is prepared by a known method, and a prepreg of alumina fiber is wrapped around the outer surface of the reinforced composite, and the structure can be obtained in the same manner as for the tubular structure. I can do it.

In particular, the structure of the present invention has various strengths as mentioned above and can be colored, so it has a good appearance and is suitable for use in long objects such as fishing rods, golf shafts, and robot arms.

<Effects of the Invention> The structure of the present invention has excellent mechanical properties such as crushing strength, buckling strength, and torsional properties without impairing the properties of conventional FRP.

<Example> Next, the present invention will be explained in more detail.
The present invention is not limited thereto.

Example 1 A mandrel with a diameter of 15 mm, a length of 1200 mm, and a taper of 1.5/1000 was coated with prepreg (ALF fabric weight) of Sumika alumina fiber (diameter 15 μ) [manufactured by Sumitomo Chemical Co., Ltd.].
A narrow tape of 2 mm width (235 g/m ² , epoxy resin content 30 wt%) was spirally and closely spaced at one end in the longitudinal direction so that the fiber direction was 88° with respect to the length direction of the mandrel. It was continuously wrapped once over a length of 1000 mm from one end to the other end. On top of that, carbon fiber alignment prepreg sheet IM-6/J-1201
(CF fabric weight 130g/m ² , resin content 38wt%) [manufactured by Sumika Harkyuress Co., Ltd.] was wound three times so that the fiber direction coincided with the length direction of the mandrel, and a 20μ thick polyethylene terephthalate tape was wrapped on top of it. It was wound and heated at 80°C for 1 hour and then at 120°C for 2 hours to form a pipe with an outer diameter of 16 mm, a length of 1000 mm ² and a thickness of 0.5 mm.

The bending strength of this pipe is 105Kg/mm ² , the bending modulus is 18t/mm ² , the crushing strength is 30Kg/mm ² , and the buckling strength is
It was 150Kg/ ^mm2 .

Comparative Example 1 The carbon fiber aligned prepreg sheet used in Example 1 was made into a narrow tape with a width of 2 mm, and similarly wrapped once in a spiral shape around the same mandrel as in Example 1. Other than that, in the same manner as in Example 1, a carbon fiber aligned prepreg sheet was wrapped three times so that the fiber direction coincided with the length direction of the mandrel, and tape wrapping was performed to obtain an outer diameter of 16 mm and a length of 1000 mm. , thickness
A 0.5mm pipe was molded.

The bending strength of this pipe is 95Kg/mm ² , the bending modulus is 13t/mm ² , the crushing strength is 20Kg/mm ² , and the buckling strength is 125
It was Kg/ ^mm2 .

Example 2 In the outermost layer of the laminated structure wrapped in Comparative Example 1, 1000 Sumika alumina fibers (diameter 15μ) [manufactured by Sumitomo Chemical Co., Ltd.] were arranged in one direction.
Alumina fiber tow prepreg impregnated with about 30wt% epoxy resin was spread over a length of 1000mm from one end to the other end with a pitch of 35mm so that the fiber direction was ±45° with respect to the length direction of the mandrel. The tape wrapping was formed in the same manner as in Comparative Example 1, except that it was wound in a twill shape, and the outer diameter was 16 mm and the length was 1000 mm.
A pipe with a thickness of 0.5 mm and a thickness of 0.5 mm was formed.

The bending strength of this pipe is 125Kg/mm ² , the bending modulus is 13t/mm ² , the crushing strength is 25Kg/mm ² , and the buckling strength is
It was 150Kg/ ^mm2 .

Comparative Example 2 The outermost layer of the laminated structure wrapped in Comparative Example 1
3000 carbon fibers [IM- manufactured by Sumika Harkyuress Co., Ltd.]
Example 2 A carbon fiber tow prepreg prepared by impregnating approximately 30 wt% of epoxy resin with [6]
The comparison was made in the same manner as in 35mm pitch, except that the fiber direction was wound at ±45° with respect to the length direction of the mandrel over a length of 1000mm from one end of the length direction to the other end. Tape wrapping molded in the same way as Example 1, outer diameter 16 mm, length 1000 mm, thickness 0.5
mm pipe was formed.

The bending strength of this pipe is 100Kg/mm ² , the bending modulus is 13t/mm ² , the crushing strength is 22Kg/mm ² , and the buckling strength is
It was 130Kg/ ^mm2 .

Claims (1)

[Claims] 1. At least one type of fiber selected from organic, inorganic and metal fibers is used as a reinforcing material, and synthetic resin and/or
Or in a rod-shaped or tubular structure made of a fiber-reinforced composite material with a rubber matrix, reinforcing fibers containing at least 50% by volume of fibers with a fiber orientation angle of 0 to 20 degrees with respect to the longitudinal direction of the structure. 72% by weight or more of Al ₂ O ₃ on the inner and/or outer surface of the structure,
Alumina fibers containing 28% by weight or less of SiO ₂ and showing substantially no α-Al ₂ O ₃ reflection in the X-ray structure are used as reinforcing materials, and the alumina fibers extend in the longitudinal direction of the structure. A fiber-reinforced structure characterized in that composite materials are laminated and integrated with fiber orientation angles of 20 to 90 degrees. 2 At least one type of fiber selected from organic, inorganic and metal fibers is used as a reinforcing material, and synthetic resin and/or
Or, in the production of a rod-shaped or tubular structure made of a composite material with a rubber matrix, reinforcing fibers containing at least 50% by volume of said fibers with a fiber orientation angle of 0 to 20 degrees with respect to the longitudinal direction of the structure. 72% or more of Al ₂ O ₃ by weight on the outer surface of the structure made of material,
Width reinforced with alumina fibers containing 28% by weight or less of SiO ₂ and showing virtually no α-Al ₂ O ₃ reflection in the X-ray structure, and impregnated with synthetic resin and/or rubber. Continuous prepreg of 0.5 to 10 mm is applied 20 to 90 times along the length of the structure.
1. A method for producing a fiber-reinforced structure, which comprises winding the fibers at a certain fiber orientation angle and then heat-forming them.