JPS6277928A - Cylindrical member made of fiber-reinforced composite material and its manufacture - Google Patents

Abstract

PURPOSE:To enable improvements is specific strength and specific rigidity, by setting up an oblique angle of a direction of a reinforcing fiber to be formed with a bus bar of a cylindrical member less than a specific angle. CONSTITUTION:A reinforcing fiber 3 is arranged by slanting a direction of the same at an angle theta of less than 20 degrees with a bus bar L of a cylindrical member and a slanting direction of the reinforcing fiber 3 is set up so that the slanting direction in a layer becomes opposite mutually to the other adjoining layer, in each of layers in the cylindrical member made of a fiber-reinforced composite material having a plurality of layers laminated from the inside to the outside. A prering 4 is formed by winding the reinforcing fiber 3 cylindrical round a matrix, in a manufacturing method. The oblique angle theta of a cutting line 5 of the prering to be formed with the bus bar L becomes that of the reinforcing fiber 3 in each of the layer of the cylindrical member. therefore, it becomes possible to set up the oblique angle of the reinforcing fiber at an arbitrary one of less than 20 degrees and specific strength and specific rigidity can be improved than those in the past.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a cylindrical member made of a fiber-reinforced composite material such as fiber-reinforced metal (FRM) or fiber-reinforced plastic (FRP), and a method for manufacturing the same.

(Prior Art) Cylindrical members made of fiber-reinforced composite materials are known, for example, as described in [Journal of the Japan Society for Composite Materials, Vol. 9, No. 3 J (published March 1983). Composite materials are used in this cylindrical member in order to improve the specific rigidity and specific strength of the member, but in order to reduce the anisotropy of the composite material, the following structure is used. has been adopted. That is, the cylindrical member is constructed by laminating a plurality of layers, and the inclination angles of the reinforcing fibers with respect to the generatrix are opposite to each other between each layer.

(Problems to be Solved by the Invention) Incidentally, the inclination angle of each reinforcing fiber with respect to the generatrix in the above-mentioned cylindrical member is set to be large, such as 45 degrees or more with respect to the generatrix of the member.

This is because the cylindrical member is manufactured by winding reinforcing fibers around the cylindrical member while rotating the member, and therefore the inclination angle cannot be made small. As a result of such a large inclination angle of each reinforcing fiber with respect to the generatrix, the conventional cylindrical member described above has the disadvantage that it is not possible to obtain the large specific strength and specific stiffness characteristic of fiber-reinforced composite materials.

The present invention was made to solve the above-mentioned conventional drawbacks, and its purpose is to provide a cylindrical member made of fiber reinforced composite material having sufficient specific strength and specific stiffness, and a method for manufacturing the same. It's about doing.

(Means for Solving the Problems) ・) In the cylindrical member made of fiber reinforced composite material of the present invention, the cylindrical member made of fiber reinforced composite material has a plurality of layers laminated from the inside to the outside. In each layer of the shaped member,
The direction of the reinforcing fibers is arranged at an angle of 20 degrees or less with respect to the generatrix of the cylindrical member, and the direction of inclination of the reinforcing fibers in one layer is opposite to that of other adjacent layers. is set to be.

In addition, in the method for manufacturing a cylindrical member made of fiber-reinforced composite material of the present invention, reinforcing fibers are wound around a matrix in a cylindrical shape to form a pre-ring, and this pre-ring is tilted at an angle of 20 degrees or less with respect to the generatrix. A substantially parallelogram preform material is formed by cutting along a cutting line having The reinforcing fibers are wound in a cylindrical shape in the direction in which the fibers are formed, and on top of that, a preform material having reinforcing fibers inclined in the opposite direction to the above and formed approximately 1q as above is wrapped, and a diffusion treatment is applied to this. That's how it is.

(Function) In the above manufacturing method, the angle of inclination of the cutting line of the pre-ring with respect to the generatrix line becomes the angle of inclination of the reinforcing fibers in each layer of the cylindrical member. Therefore, according to this method, it is possible to set the inclination angle of the reinforcing fibers to any angle of 20 degrees or less. According to the cylindrical member having a small fiber inclination angle, the specific strength and specific stiffness can be improved more than before.
It is possible to do so.

(Example) Next, a cylindrical member made of fiber-reinforced composite material of the present invention and a method for manufacturing the same will be described in detail with reference to the drawings.

First, an example of the manufacturing method will be explained. As shown in FIG. Apply resin to the surface. For this resin, methyl methacrylate and butyl methacrylate are used to prevent contamination when the matrix metal foil becomes a reducing gas during thermal decomposition and exposes clean metal under pressure as described later. Preference is given to using copolymers. While the resin is not drying and solidifying, reinforcing fibers 3, such as silicon carbide fibers, are wound around the surface of the resin at a predetermined pitch over a predetermined width B to create a pre-ring 4. After solidification of the resin, the pre-ring 4 is removed from the mandrel 1, and as shown in FIG. , a parallelogram-shaped preform 6 as shown in FIG. 3 is formed.

Next, as shown in FIG. 4, this preform material 6 is wound around a mandrel 7 having a diameter Df=B/(π·D −cos θ). In this case, the preform material 6 has a pair of side edges 8, 8 parallel to the reinforcing fibers butted against each other, and a pair of side edges 9, 9 formed by the cutting line 5 is connected to the formed cylindrical body. Be sure to position it at both ends of the As a result of wrapping the preform material 6 in this way, the reinforcing fibers 3 are
It is arranged to be inclined by the same angle θ as the cutting angle θ with respect to the generatrix of the cylindrical body to be formed.

Then, another preform material IO is manufactured in which the inclination angle θ of the cutting line 5 with respect to the generatrix line is opposite, that is, the inclination angle −θ with respect to the generatrix line is opposite to the above, and this is
As shown in the figure, it is wrapped from above the preform material 6.

Next, another preform material 11 having an angle of inclination θ in the same direction as the first preform material 6 is wrapped around the second preform material 10, thereby forming a cylinder. While alternating the inclination angle of the reinforcing fibers with respect to the generatrix of the shaped body as +θ, -θ, +θ...
A predetermined number of layers are laminated to produce a cylindrical substrate 12 (FIG. 6). Next, as shown in FIG. 6, desired metal fittings 13 are attached to both ends of the cylindrical base 12, and in this state the entire body is hermetically covered with metal foil. Next, the pressure inside each layer is reduced to a substantially vacuum state, and a diffusion treatment such as hot isostatic pressure treatment is applied to this to produce a cylindrical member.

Next, the reason why the inclination angle θ of the reinforcing fibers 3 with respect to the generatrix of the cylindrical member is set to 20 degrees or less in the above will be explained. First, Figure 7 shows a fiber-reinforced composite material (fiber content: 5
0%), the relationship between stress σ and strain ε is shown when the reinforcing fiber direction is inclined at various angles with respect to the direction of stress application.

Note that the broken line in the figure indicates the breaking point of the reinforcing fiber. It is clear from the figure that as the inclination angle of the reinforcing fibers with respect to the direction of stress application increases, particularly when it exceeds 20 degrees, the strain ε increases rapidly. In particular, when the inclination angle θ = 20 degrees, the strength decreases by about 15% at the breaking point of the reinforcing fibers, but the strain decreases by about It has increased 10 times. Since this level of strength and elongation is sufficient for practical use, the inclination angle θ of the reinforcing fibers is set to 20 degrees or less. Note that in order to ensure sufficient elongation, it is preferable to set the above-mentioned inclination angle θ to be larger than 10 degrees.

By setting the inclination angle of the reinforcing fibers in the cylindrical member to 20 degrees or less as described above, the member has excellent strength, rigidity, and appropriate elongation. It becomes possible to improve strength and specific stiffness. Furthermore, when manufacturing a cylindrical member using the above method, the cylindrical member can be easily manufactured while arbitrarily changing the inclination angle of the reinforcing fibers, and furthermore, there is no waste during the above manufacturing process. Since there is no material required, it is possible to manufacture the above-mentioned cylindrical member at low cost.

In the above example, an example was shown in which an aluminum alloy was used as the matrix of the composite material, but the matrix could also be other metals (Mg, Ti, Ni, Cu, etc.), ceramics (Sin, 81,0. The□
etc.), amorphous, plastic, concrete, rubber, etc. can be used. In addition, as reinforcing fibers, ceramic fibers other than the above-mentioned silicon carbide (B, C
, Sin, , AI, 03, ZrO2, etc.), fully bent fibers (
W, Mo, stainless steel, etc.), whiskers, glass fibers, polymer fibers, etc. can be used.

In the above example, the cylindrical member is made of fiber-reinforced composite material, but it may also have a rectangular cross section.

(Effects of the Invention) In the cylindrical member made of fiber-reinforced composite material of the present invention, the inclination angle of the reinforcing fibers with respect to the generatrix of the member is set to 20 degrees or less as described above, so that the inclination angle of the conventional inclination angle is set to 20 degrees or less. It becomes possible to significantly improve specific strength and specific rigidity compared to larger ones.

Further, in the method for manufacturing a cylindrical member of the present invention, the cylindrical member is manufactured by a simple operation of manufacturing a pre-ring by wrapping reinforcing fibers, cutting the pre-ring, and wrapping the preform material thus created. Therefore, the cylindrical member can be manufactured with high efficiency.

[Brief explanation of drawings]

Figures 1 to 6 are explanatory diagrams illustrating an example of the manufacturing method of a cylindrical member made of fiber-reinforced composite material over time according to the present invention, and Figure 7 is the relationship between stress and strain of the fiber-reinforced composite material. This is a graph showing. 3... Reinforcing fiber, 4... Pre-ring, 5... Cutting line, 6.10.11... Preform material, 8.8...
・Side edge, 9.9...Side edge.

Claims (1)

[Claims] 1. In a cylindrical member made of fiber-reinforced composite material having a plurality of layers laminated from the inside to the outside, in each layer, the direction of the reinforcing fibers is relative to the generatrix of the cylindrical member. The reinforcing fibers are arranged at an angle of 20 degrees or less, and the direction of inclination of the reinforcing fibers is set to be opposite to that of the other adjacent layers in one layer. A cylindrical member made of fiber-reinforced composite material. 2. A pre-ring is formed by winding the reinforcing fibers around a matrix in a cylindrical shape, and a substantially parallelogram-shaped preform material is formed by cutting this pre-ring along a cutting line having an inclination of 20 degrees or less with respect to the generatrix. Then, this preform material is wound into a cylinder shape in a direction in which a pair of side edges parallel to the reinforcing fibers are brought close to each other, and the above cutting line becomes the side end, and then wrapped on top of it in a direction opposite to the above. A method for producing a cylindrical member made of a fiber reinforced composite material, characterized in that reinforcing fibers are inclined, a preform material formed in substantially the same manner as described above is wrapped, and a diffusion treatment is applied to the preform material.