JPH0358836A - Composite molded product - Google Patents

Abstract

PURPOSE:To enhance impact resistance by fixing fiber reinforced plastic based on a high strength fiber and containing a thermoplastic resin as a binder to the whole or part of the opposite surface to a side where flying matter impinges of a metal plate or a molded product thereof. CONSTITUTION:High strength fiber reinforced plastic 2 based on a high strength fiber and containing a thermoplastic resin as a binder is fixed to the whole or part of the rear of a metal plate 1 or a molded product thereof by bolts 3 to obtain a desired composite molded product. At this time, the thickness of the metal plate 1 is set to 1 - 30mm and that of the fiber reinforced plastic 2 is set to 0.4 - 25mm.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to a metal plate or a molded product having a thermoplastic material having a high-strength fiber as a base material on the opposite side (hereinafter referred to as the back side) of the side that is hit by flying objects. The present invention relates to a composite shaped article that is lightweight and has excellent impact resistance by fixing resin fiber reinforced plastics by a mechanical method or a chemical method such as adhesion.

[Conventional technology]

Impact-resistant bodies against flying objects such as objects falling from high places are
A single material such as iron or aluminum alloy, a multi-layered material thereof, or a composite material in which a layer of plastic or ceramic is provided between metal materials are effective. Such an impact-resistant body requires a certain thickness in order to maintain predetermined properties, and therefore weight cannot be reduced.

Research has also been done on inserting fiber-reinforced plastics based on high-strength fibers between metal bodies, but such composites are fixed with metal bodies from both sides, making it difficult to use fiber-reinforced plastics. The drawback was that it could not make full use of its energy absorption properties.

[Problem to be solved by the invention]

The present inventor has developed a high-strength fiber-reinforced plastic (hereinafter referred to as A
We found that CM) has excellent impact resistance, and after investigating various ways to combine it with a metal body, we found that A
By fixing CM to the back surface of a metal body, a composite shaped article with high impact resistance has been completed.

[Means to solve the problem]

The present invention is a composite molding characterized in that a high-strength fiber-reinforced plastic made of high-strength fiber as a base material and a thermoplastic resin as a binder is fixed to the entire back surface or a part of the back surface of a metal plate or a molded product thereof. It is a thing.

The high-strength fiber used in the present invention has a specific tensile strength (tensile strength divided by density) of IOXIO'cm or more, and a specific elastic modulus (modulus of elasticity divided by density) of 2.5XlO'C.
m or more. Specifically, high-strength glass fiber,
These include carbon fiber, aramid fiber, aromatic polyester fiber, high strength polyethylene fiber, and vinylon fiber.

General glass fibers, nylon fibers, polyester fibers, etc. are not applicable. If the specific tensile strength or specific modulus is less than the above value, the impact resistance of the composite molded product of ACM and the metal body is not necessarily sufficient.

Thermoplastic resins to be applied or impregnated into these high-strength fibers include polyolefins such as polyethylene and polypropylene, polyamides, polyesters, polyvinyl acetates, polyether sulfides, polyphenyl sulfides, polyether ether ketones, thermoplastic polyurethanes, synthetic rubbers, etc. It is.

To obtain ACM, a compression molding method is usually used, in which high-strength fibers are impregnated or coated with a thermoplastic resin solution, powder, or its dispersion solution to create a prepreg, and multiple sheets of this prepreg are stacked and heated and pressed. adopt. At this time, the resin content is 5 to 8
It is in the range of 0% (wt%, same below), but usually 5-
50%, preferably 10-30%. The smaller the resin content, the greater the energy absorption capacity against impact force, but if it is less than 5%, it is difficult to make a pre-reg, and even if it is more than 80%, it is difficult to make a pre-reg, and the impact resistance is less than 50%. There is a tendency to decrease.

In the present invention, the thickness of the metal plate is usually 1 to 30 mm. If the thickness is less than 1 mm, the effect of providing the metal plate is small, and 30
If it is more than mm, it is difficult to obtain the effect of weight reduction.

The preferred thickness is 1.5 to 5 mm.

On the other hand, the thickness of ACM is usually 0-4-25 mm. 0
．． If the thickness is 4 mm or less, the impact energy absorption effect is small, and even if the thickness is 25 mm or more, the impact energy absorption effect does not change much. The preferred thickness is 1.5 to 8 mm.

The ACM thus obtained can be fixed to the back surface of a metal plate or its molded product by a mechanical method using bolts, rivets, frame materials, etc., or by bonding with a rubber-based adhesive or the like. Fix by method. Note that when fixing, a space may be provided between the metal plate and the ACM.

Examples of the structure are shown in FIGS. 1 to 3. In either case, it is the metal plate side that is hit by the flying object. Figure 1 shows the metal plate and AC
M is fixed with bolts.

Figure 2 shows a metal plate that has been two-dimensionally processed and an ACM fixed with adhesive. In Figure 3, a metal plate is three-dimensionally processed into a hemispherical shape, and a similarly hemispherical ACM is fixed with bolts.

[Example] The present invention will be explained below with reference to Examples.

Example l Specific tensile strength 1 6 X l O'am, specific modulus 3
．． A woven fabric (thickness 0.45 mm, basis weight 500 g/m) made of high-strength glass fiber of 2 x 10"cm is impregnated with a 15% MEK solution of acrylic resin and dried to produce a prepreg (610 g) with a resin content of 18%. /mQ was produced.Four sheets of this brev leg were stacked and weighed 2 8 0 '0, 1 0 0 Kg.
/cm" to obtain a high-strength glass fiber reinforced acrylic resin ACM board.

Taps were cut in the four corners of a steel plate of size 300 x 300 x 3.5 mm, and the ACM plate was fixed with bolts from the back side of the steel plate to produce a composite plate as shown in Figure 1.
child.

Example 2 Specific tensile strength: 20 X l O'cm, specific modulus of elasticity: 4.
A prepreg (306
g/m”) was produced. Six sheets of this Bripreg were stacked and two
An aromatic polyester fiber reinforced nylon ACM board was obtained by heating and pressing at 20°Cs 70Kg/cm2.

Taps were cut in the four corners of a steel plate measuring 300 x 300 x 3.5 mm, and the ACM plate was fixed with bolts from the back side of the steel plate to produce a composite plate as shown in Figure 1.

Comparative Example I A 5 mm thick steel plate of the same quality as that used in Example I was used as it was.

Example 3 Specific tensile strength 2 1 × 1 0 'am, specific modulus 6.
A 4 x 10'cm woven fabric made of aramid fibers (thickness 0.
45mm, basis weight 500g/m, 18%M of ABS resin
It was impregnated with an EK solution and dried to produce a prepreg (625 g/m') with a resin content of 20%. 6 sheets of this prepreg were stacked and placed in a mold with a quadratic curved surface, 150'O, l
An aramid fiber-reinforced ABS resin ACM board was obtained by heating and pressing at a pressure of 0.0 kg/cm''.

This was adhered and fixed to the back side of a 5 mm thick aluminum alloy plate having the same curved surface using a synthetic rubber adhesive to produce a composite plate as shown in FIG. 2.

Comparative Example 2 An aluminum alloy plate having the same quality as that used in Example 3 and having a thickness of 8 mm was used as it was.

Comparative Example 3 Aramid fiber reinforced ABS resin ACM obtained in Example 3
The plate was adhesively fixed to the surface side of the aluminum alloy plate used in Example 3 using the adhesive described above.

Comparative Example 4 Aramid fiber reinforced ABS resin ACM obtained in Example 3
The plate was inserted between 2 mm and 3 mm thick aluminum alloy plates with the same curved surface and fixed with bolts and nuts. Note that the aluminum alloy plate on the front side was 2 mm thick.

Example 4 Fine powder of polybutylene terephthalate (PBT) resin was sprayed onto the high-strength glass fiber woven fabric used in Example 1 to produce a prepreg (625 g/m2) with a resin content of 20%. The sheets were stacked, placed in a hemispherical mold, and heated and pressed at l 5 0'OSI O OKg/cm'' to obtain a high-strength glass fiber reinforced PBT resin ACMtC shaped article.

Thickness 1. Put it into the inner surface of a 5 mm hemispherical steel shape, fix the spherical rib-like part with bolts and nuts,
A composite molded article as shown in FIG. 3 was obtained.

Comparative Example 5 Same material as that used in Example 4, thickness 2. 5mm
The hemispherical steel body was used as is.

For composite shapes in each example, JIS T 813
Impact resistance test results based on 3, thickness of molded product and lm2
The weight per unit was measured and the results are shown in Table 1. In the impact resistance test, an impact was applied to the front side of the molded product.

In Examples 1 and 2 of Table 1, 80M is provided only on the back side of the metal plate, so compared to the case of only the metal plate in Comparative Example 1,
Excellent impact resistance and weight reduction achieved - Example 3 also achieved excellent impact resistance and weight reduction compared to Comparative Example 2. In Comparative Examples 3 and 4, the metal plate in Example 3 was provided on the back side of the ACM or divided into the front side and the back side, so the impact resistance was inferior to that in Example 3. Example 4
Also in the case of Comparative Example 5, the impact resistance was excellent and the weight was reduced.

〔Effect of the invention〕

As is clear from the above examples, the composite molded product of the present invention can reduce the weight by 20 to 60% when the impact resistance is equal to or higher than that of a conventional impact-resistant metal body. can.

If the ACM is provided on the surface side of a metal body or inserted between metal bodies, the impact resistance effect of the ACM will be considerably reduced, and there will be little merit in using a composite plate.

When the ACM is provided only on the back side of the metal body, compared to the case where only the metal body is used or the case where the ACM does not use the metal body,
Impact resistance increases by 25-50% for the same weight.

[Brief explanation of drawings]

1 to 3 show examples of the structure of the ACM of the present invention, FIGS. 1 and 2 are perspective views, and FIG. 3 is a sectional view.

Claims (3)

[Claims] (1) A fiber-reinforced plastic made of high-strength fiber as a base material and a thermoplastic resin as a binder is fixed to the entire surface or a part of the opposite side of the metal plate or its molded material to the side that is hit by flying objects. Composite molded product with characteristics. (2) A fiber-reinforced plastic obtained by heating and press-molding a prepreg obtained by impregnating or coating a high-strength fiber base material with a thermoplastic resin solution, powder, or dispersion thereof, can be used as a metal plate or a molded product thereof. A composite molded article that is fixed to the entire surface or a part of the opposite side to the side that is hit by flying objects. (3) A composite molded article, wherein the metal plate has a thickness of 1 to 30 mm, and the fiber reinforced plastic has a thickness of 0.4 to 25 mm.