JPS63218339A - Manufacture of composite girder material - Google Patents

Abstract

PURPOSE:To make it effective in manufacturing girder materials having various cross sections, exellent in productivity and profitable in cost by a method wherein a resin-impregnated fiber is wound round a mandrel and, after being semi- hardened, removed from the mandrel, deformed in an intended shape and finally the resin is hardened under the state that said intended shape is maintained. CONSTITUTION:Resin and fiber are selected and the winding angle is selected to be 5-30 deg. or 60-88 deg.. A resin-impregnated fiber is wound round a mandrel, to which Teflon coating is applied. When the predetermined winding is finished, the fiber is semi-hardened as wound up. When the predetermined viscosity or 10<3>-10<7> P is attained by the resin of the fiber, the fiber is removed from the mandrel. Firstly, the central parts of the fiber are joined by pressure to each other and, after that, the remaining loop-shaped parts are also joined by pressure for hardening. For industrial production, an intermediate stock 1, which is produced by FW (filament winding) method is joined by pressure with pressure-joining rollers 5 and bonded with pressure-joining heaters 6. If necessary, the fiber is finally hardened in a curing oven under the state that the shape of the fiber is kept with an auxiliary shape retaining tool.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a beam girder material made of fiber reinforced plastics (hereinafter referred to as FRP) and a method for manufacturing the same, in particular, a method for filling by the filament wine tongue method (hereinafter referred to as FW method).
It relates to a method of impregnating a strand with resin and winding it onto a mandrel.

[Prior Art and Problems Therewith] A beam girder material made of a composite material made of fibers and resin has already been devised as a lightweight and high-strength girder material, and its manufacturing method is well known.

For example, Japanese Patent Publication No. 61-12781 discloses beam girder materials made of composite materials using essentially the traditional prepreg method, while Japanese Patent Publication No. 61-179731 and the 4th Next Generation Industrial Infrastructure Technology Symposium - Metal/Composite Materials Technology -The so-called resin transfer Mortang method (hereinafter referred to as RTM) was used for the secondary manuscript collection.
Composite material beam and girder materials according to the method (abbreviated as "method") are described.

FRPWA beam materials made by these methods have a lower fiber content (hereinafter abbreviated as vl) than other methods, such as injection molding of resin containing short fibers such as milled fibers.
Although the fiber properties are well utilized, there are problems with productivity, etc., and it cannot be said that it is particularly suitable for continuous production, automated production, mass production, etc.

Similar to these methods, the filament winding method has a high vl and can make maximum use of the physical properties of fibers. Although it is used for various purposes such as pipes and cylinders, it is not suitable for use as a structural material for beams and girders. Almost limited to tubular objects.

As a result of various studies regarding the above-mentioned problems, the present inventors have completed the method of the present invention, which is effective in manufacturing girder members of various cross sections, has excellent productivity, and is relatively advantageous in terms of cost.

Composite beam girder materials were originally conceived using the prepreg method. In other words, a thermosetting resin raw material is infiltrated into a thin layer of aligned fiber rows, and this is semi-cured (referred to as a B-stage thorn) to form a semi-cured resin intermediate containing fibers. The material is cut to the desired size and shape, pasted together to form a structural material, and completely cured to form a composite beam girder material. The invention described in Japanese Patent Publication No. 61-12781 is also substantially based on this method. Since this method is time-consuming and not an easy manufacturing method, improvements are being considered, such as the so-called RTM method. In this method, fibers are formed in advance into the shape of a required composite material beam beam material, and this fiber-forming acid-forming resin is permeated into the fibers to form a resin molded product. Generally, the fiber formed product is placed in a mold, and an uncured thermosetting resin or a raw material is press-fitted and infiltrated into the mold. The invention described in JP-A-61-179731 is also substantially based on this method. Even with this method, there are challenges in assembling the reinforcing fiber product and injecting and permeating the resin into this structure.

[Means for Solving the Problem] In order to solve the above problem, the inventor considered the use of the FW method.

It is already known that composite beam girders can be made using the FW method. The FW method produces tubular moldings, and it is therefore often considered to produce tubular structural materials with this method.

The present inventor differs from these methods by taking up filament winding technology as a means of making intermediate materials for composite materials.
We investigated a method for rationally making non-circular tubular materials, such as 1-beam, not just circular tubular materials, using composite materials, and arrived at the present invention.

Therefore, the problems in this method are broadly divided into the production of intermediate materials and the production of beam girder materials from intermediate materials.

When making an intermediate material for a composite material of fiber and resin using the FW method, we consider what kind of properties the intermediate material should have, keeping in mind the final product, and what kind of m-fiber and resin to choose.
The most important issue is how to wind it up. However, when handling this FW method special product intermediate material,
How to skillfully remove it from the mandrel is also an extremely important issue.

When handled as an intermediate material, the resin has not completely cured, and therefore remains sticky and easily deformed. When handled as an intermediate material, it is often handled without removing it from the mandrel, but the inventor of the present invention considered removing it in consideration of convenience in molding the final product. Although it is possible to deform the mandrel, it is preferable to detach it from the mandrel in consideration of repeated use. When detached from the mandrel, it is preferable to wrap or coat the mandrel with some kind of polyester, Teflon, etc. However, this alone does not solve the problem and deforms when force is applied during removal.

It has been found that the viscosity of the resin at the time of removal is an important factor in keeping the amount of deformation within a predetermined range, and the winding angle of the fibers is also an important issue.

The viscosity of the resin at the time of removal is required to be at least 103 voids, and it is important that the fibers be rolled up at multiple angles, and it is preferable to use a combination of shallow angles and deep angles with respect to the winding axis. The formation of multiple layers with different winding angles has a great effect on the viscosity of the resin when it is removed, as well as on the ease with which deformation occurs when force is applied for removal. It is preferable to include the side along which the angle is closest.

Thus, the intermediate material of the cylindrical body is composed of flat and/or outwardly convex surfaces, i.e., where the cross section cut by a plane perpendicular to the axis is composed of straight lines and/or outwardly convex curves. A cylindrical intermediate material is obtained.

When forming an intermediate material into a product, it is deformed and hardened, but an important issue is how to crush the tubular intermediate material when forming an IT beam or the like. This may depend on the viscosity of the resin, the ratio of resin to fiber, etc.According to the study results of the present inventors, the local deformation is 1 mm or more for reinforcing fibers, glass fibers, or carbon fibers, and 0.5 mm for aramid fibers.
If it is not more than mm, the strength of the final product will be significantly reduced. In addition, the amount of resin is more than 0.4 times that of fiber, and the resin viscosity is 1
If it is less than 0.07 poise, the strength will similarly decrease. Regarding the fiber winding direction, it is preferable to wind the fiber at multiple angles due to the strength of the beam girder material, and there are layers at 5 to 30 degrees and layers at 60 to 88 degrees with respect to the axis, including the separation of the intermediate material from the mandrel. It is preferable.

During this transformation, it is possible, and sometimes preferable, to add new ensign resin to the interior of the intermediate material. This happens when the resin in the intermediate material hardens too much, reducing adhesive strength. Further, at this time, reinforcing fibers may be added, but they are basically not necessary if the fiber direction can be planned appropriately at the time of initial planning.

In this way, a cylindrical body or a rod-shaped body (round bar, square bar, L-, I- or T-shaped bar, etc.) having at least a flat or concave surface on the outside is obtained. That is, a cylindrical or rod-shaped body whose cross section taken along a plane perpendicular to the axis is formed of at least a straight line or an outwardly concave curve is obtained.

[Function] In the above method, a good composite beam girder material made of fibers and resin can be produced at low cost. Moreover, by adopting this method, a method close to automation and continuity can be adopted.

In other words, unlike the conventional prepreg method, it is not necessary to bond materials together, and products can be created by deforming and curing intermediate materials.It is also possible to create a fiber-reinforced structure as in the RTM method, and it is not possible to inject resin into this structure. Not necessary. In other words, it is relatively easy to obtain an intermediate material in which resin and reinforcing fibers are integrated, and this intermediate material can be similarly easily deformed and hardened into a product.

FIG. 1 shows an example of the modification of this intermediate material, taking as an example an I-beam. In other words, the intermediate material (cylindrical in this case) rolled up by the FW method is pressed and bonded by pressing the center portion, and then the annular portions remaining on the top and bottom are crushed to form an I-shape and the resin is cured. First, the center part of the intermediate material is pushed to one side while being crushed, and if only one annular part is left, it becomes a T-beam.

In the same way, it can also be converted into an L beam.

The resin and reinforcing fibers are determined as necessary and are not particularly limited. Depending on the purpose, reinforcing fibers are selected from carbon fiber, glass fiber, aramid fiber, and other reinforcing fibers.

It is also possible to use multiple 1Iffs together. Thermosetting resin is generally used as the resin. However, thermoplastic resin may also be used. A mixture of both is also possible. In the case of thermosetting resins, epoxy resins, unsaturated polyesters, vinyl ester resins, polyimides, and others are selected depending on the purpose. In the case of a thermoplastic resin, it can be used by dissolving it in a solvent, or the solvent can be used as a reaction suppressing solvent such as a lactam, or it can be used as a polymer or oligomer such as an epoxy resin.

Hereinafter, this invention will be specifically explained based on FIG. 1.

Resin and fiber are selected according to the general FW method, and the winding angle is selected from 5 to 30 degrees and 60 to 88 degrees. The fibers are impregnated with resin and wound onto a mandrel coated with Teflon. Once the prescribed winding is completed, it is semi-cured as it is.

When the viscosity reaches a predetermined value, that is, 10 3 to 10 7 poise, it is removed from the mandrel, and as shown in FIG. 1, the center portion is crimped as described above, and the remaining annular portion is crimped and cured.

FIG. 2 is an example of a method for industrially implementing the method of the present invention.

The intermediate material (1) made by the FW method as described above is crimped with a crimping roller (2), bonded with a crimping heater (3),
While passing through a guide (4), it is pressed by a pressure roller (5) and bonded by a pressure heater (6). If necessary, it is finally cured in a curing oven while maintaining its shape using auxiliary tools.

[Effects] Since the present invention is as described above, a composite material beam girder material made of FRP can be easily produced at low cost.

Unlike the method shown in Japanese Patent Publication No. 61-12781, there is no need for the trouble of gluing prepreg, and the method disclosed in Japanese Patent Publication No. 61-12781
Unlike the method disclosed in Japanese Patent No. 7973, there is no problem of making a beam girder material by assembling only one piece and infiltrating it with resin. This is an extremely rational method for manufacturing composite beam girder materials.

Also, according to the method of the present invention, beam girder materials other than T, L, and I beams can also be treated with W! It is possible to build A. For example, when crimping the center part of a tubular intermediate material rolled up using the FW method, if you insert a round bar made in advance using the pultrusion method or the like into the position corresponding to the annular part, you can connect the two round bars. Structural materials can be made, and if a tubular intermediate material is only crimped at the center and then cured, a structural material that connects two pipes can be obtained.

In other words, it is a highly valuable method that has excellent industrial productivity and can produce a variety of l materials.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows the procedure for making a single-shaped rod-shaped body from a cylindrical intermediate cable according to the method of the present invention. FIG. 2 shows an example of in-house manufacturing.

Claims (1)

[Scope of Claims] 1. Winding up fibers impregnated with resin onto a mandrel, and removing the resin from the mandrel after semi-curing,
A method for manufacturing a composite beam girder material, which comprises transforming the material into a desired shape and curing the resin while maintaining the desired shape. 2. A method for manufacturing a composite material beam girder material, in which the resin-impregnated fibers are rolled up at multiple angles with respect to the axis. 3. A method for manufacturing a composite material beam girder material, in which at least one of the winding angles of the fibers is 5 to 30 degrees with respect to the axis, and the other one is 60 to 88 degrees. 4. A method for producing a composite material beam girder material, in which, after the resin is semi-cured, when the resin is removed from the mandrel and deformed, all the curved portions in the cross section cut at right angles to the axis have a radius of 1 mm or more.