JPH042423B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method of joining fiber-reinforced plastic (hereinafter abbreviated as FRP) and metal.
This article relates to adhesive bonding between FRP cylindrical objects and metal fittings such as roll headers and propeller shaft yokes.

[Conventional technology]

FRP is lightweight and highly rigid, and exhibits excellent performance when used in various structures. However, the joints with other structural members are generally complex in shape, and have poor wear resistance and scratch resistance. Since flexibility is also required, metal fittings are used by adhesively bonding them to FRP.
It is very important to increase the adhesive strength, improve the reliability of the adhesive, and improve the mechanical bonding precision of the adhesive. Conventionally, when bonding this FRP cylindrical object and metal fitting, the adhesive gap between the inner diameter of the cylinder and the outer diameter of the fitting is 70~
The conventional technique is to insert the metal fitting straightly as shown in Figure 2 while ensuring a radial gap of 200 μm, or to insert and bond the metal fitting with two tight fitting parts as shown in Figure 3. It is.

[Problem that the invention seeks to solve]

When bonding straight type metal fittings shown in Figure 2, the bonding gap is usually 70 to 200 μm (radial gap) to ensure bonding strength.
Glue within the range of . Therefore, when the adhesive heats and hardens, the viscosity of the adhesive decreases, and the metal fitting moves slightly within the bonding gap, resulting in misalignment or mounting angle between the center of the FRP cylindrical object and the center of the metal fitting. However, it is not possible to obtain highly accurate straightness. In addition, if the adhesive gap is made small in order to control delicate movement during adhesive heating, the adhesive gap disappears due to the thermal expansion of the metal fitting during heating, and the adhesive in the gap is pushed out, and after curing, the adhesive in the gap is forced out. At the same time, as the metal fitting shrinks, a gap is generated and the adhesive strength is reduced.

Therefore, it is currently very difficult to ensure mechanical bonding accuracy and adhesive strength.
In addition, the adhesive method shown in Figure 3 has better mechanical joining accuracy than the adhesive method described above, but since there are two tight fitting parts, insertion is extremely difficult, which not only takes time and effort for the adhesive work. During insertion, the adhesive applied to the inner circumference of the FRP cylinder is scraped off by the tightly fitted part of the fitting tip, which causes unevenness of the adhesive and reduces adhesive strength and reliability. There's a problem.

[Means for solving problems]

In order to solve the above-mentioned problems, the present inventors have arrived at the present invention as a result of intensive studies. The gist is that when a metal joint is adhesively bonded to the inner peripheral edge of a cylindrical object made of FRP, a ring-shaped part with a tight fit is provided at the end of the cylinder in the cylindrical insertion part of the metal joint. There is a method of joining FRP and metal joints. In this case, it is preferable that the ring-shaped tightly fitted portion has a fitting distance of 50 μm or less and a width of 6 mm or more.

The present invention is divided into a part whose purpose is to maintain mechanical bonding accuracy without expecting adhesive strength, and a part whose purpose is only to share adhesive strength without expecting accuracy, and both parts are separated. The object of the present invention is to provide an adhesive bonding method that combines functionality and facilitates bonding work.

The present invention will be explained below with reference to FIG.

By providing one tight fitting part on the shaft end side, the movement of the metal fitting due to the decrease in viscosity when the adhesive is heated and hardened is restricted, and the adhesive is prevented from flowing away due to thermal expansion of the metal. In this case, the tightly fitted part first contacts the inner diameter of the cylinder, so that the adhesive gap in the adhesive strength sharing part is maintained even during thermal expansion. or,
Since the tip of the metal fitting does not have a tight fitting part, it is very easy to insert, which not only improves the workability of gluing, but also prevents uneven adhesive from being scraped off by the tip of the metal fitting when inserted. There is no sticking, and on the contrary, the adhesive is compressed during insertion, improving adhesive strength and reliability.

〔Example〕 The present invention will be specifically explained below using Examples.

Example 1 Al headers with a length of 40 mm were attached to both ends of a carbon fiber reinforced plastic cylinder with an inner diameter of 85 mm and an outer diameter of 92 mm for the purpose of fitting with a bearing. The part with a length of 8 mm from the outer end face of the header is the tight fitting part to ensure adhesion accuracy, the remaining 32 mm is the main part to be joined, and the adhesion gap between the inner diameter of the cylinder and the outer diameter of the header is 150 μm (radial gap). The radial gap at the tight fitting part was 20 μm. The adhesive was applied to both the inner periphery of the cylinder and the outer diameter of the header, and then the header was inserted and heated at 110°C for 2 hours to harden the adhesive. The roundness of the obtained rolled cylinder was 5 μm, and the straightness was 7 μm as measured by the rotational runout of the outer diameter based on both center standards.

〔Effect of the invention〕

The method of joining FRP and metal of the present invention prevents a decrease in bond strength and bond reliability due to thermal expansion and contraction of metal during bond heating, improves bond strength, and provides a tight fit in some areas. Because of this, the mechanical joining precision in adhesion is high, and it is therefore very suitable for adhesion of parts that require a high degree of rotational balance, or parts that require polishing of the FRP cylindrical part on both center points of metal fittings. Advantageously applied.

[Brief explanation of drawings]

Figure 1 is an example of the bonding method of the present invention, Figures 2 and 3.
The figure illustrates a conventional bonding method. 1... FRP cylinder, 2... Adhesive, 3... Metal sweetening, 4, 5... Minute gap.

Claims (1)

[Claims] 1 FRP and metal joint characterized by providing a ring-shaped tight-fitting part at the cylindrical end in the cylindrical insertion part of the metal joint when adhesively joining the metal joint to the circumferential edge of an FRP cylindrical object How to join with.