JP2551287B2 - Multiaxially reinforced three-dimensional molding substrate for high energy absorption and high energy absorption composite material using the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used as a reinforcing material in, for example, a fiber reinforced composite material which is a structural member .
High energy absorption multiaxial reinforcing three-dimensional molding substrate having an orientation structure fibers (filament) in the multi-axial to and this
The present invention relates to the high energy absorbing composite material used .

[0002]

2. Description of the Related Art A fiber-reinforced composite material is a matrix in which plastics, ceramics, metals and the like are reinforced by fibers which are reinforcing materials, and exhibits excellent characteristics of specific rigidity and specific strength. However, the conventional fiber-reinforced composite material exhibits a fracture behavior that is fragile against external load, and thus it is very difficult to apply it to a structural member that requires energy absorption.

In the prior art, rubber or a resin having rubber-like elasticity has been widely applied, and in the case of composite materials,
For example, as shown in Japanese Patent Publication No. 57-20900, a three-dimensional composite material in which a reinforcing material is three-dimensionally oriented and a porous material having voids inside has been proposed. FIG. 4 is a perspective view of the conventional lattice-like porous structural member disclosed in the above publication, in which 11 is a reinforcing material and 2 is a matrix. In this lattice-shaped porous structural member, the matrix 2 is impregnated and solidified only in the reinforcing material 11 and the intersections thereof, and has voids between the reinforcing materials. Due to the high rigidity of the reinforcing material against the external load and the easy deformation of the voids, energy is absorbed and a buffering effect is exhibited.

[0004]

The rubber or the resin having rubber-like elasticity and the porous three-dimensional composite material having voids inside have hitherto been proposed, but the rigidity and strength required as a structure are low, and the application range is low. There was a problem that was limited.

The present invention has been made in order to solve the above problems, and it is a multiaxial reinforced tertiary for high energy absorption capable of obtaining a composite material which is applicable to a wide range of structural members and is excellent in specific rigidity and specific strength. The purpose is to obtain an original molded substrate.

[0006]

Means for Solving the Problems] high energy absorption multiaxial reinforcing three-dimensional molding substrate of the present invention, with respect to one external load shaft, the striatum obliquely crossing direction in a range of ± 15 to 60 ° ,
It is a three-dimensional combination. Another of this invention
The high energy absorbing composite material of the invention has a single external load shaft.
With respect to, the filaments obliquely oriented in the range of ± 15 to 60 °
Is a three-dimensional combination of three axes for high energy absorption
The reinforced three-dimensional molding base material is vacuum impregnated with matrix resin.
It is hardened.

[0007]

When an external load is applied to the composite material using the molding base material of the present invention, elastic deformation of the entire material occurs first,
Next, non-linear deformation occurs due to the large deformation of the molding substrate. At this time, the obliquely oriented filaments are deformed while sliding without interfering with each other, so that the forming base material itself is not damaged, and the external load is further increased until the material as a whole is finally destroyed. It absorbs energy. If a matrix having elasticity such as rubber is used as the matrix, the matrix deforms following the molding base material, so that the deformation becomes reversible and it is possible to handle repeated loads.

[0008]

DETAILED DESCRIPTION FIG. 1 is in the multi-axis reinforcing three-dimensional molding substrate for a high energy absorption of one embodiment of the present invention, the outer one filar
4 directions (many
Of the above-mentioned molded substrate obtained by three-dimensionally obliquely orienting in the axial direction)
FIG. 2 is a conceptual diagram of the orientation of the filaments showing the orientation direction of the filaments , and FIG. 2 is a partially enlarged cross-sectional view of the filaments used for the molding substrate. In the figure, 1 is a filament, 2 is a matrix, 3 is carbon fiber,
4 is an epoxy resin and 5 is an external load direction. That is, the figure
As shown in 1, by connecting the opposite vertices of the cube, 4
Determine the axial direction. Next, parallel to each axis,
Of high energy of one embodiment of the present invention
-Obtain a multiaxially reinforced three-dimensional molded substrate for absorption. As described above
Then, the filament 1 is diagonally crossed at 45 ° with respect to the external load direction 5.
It is possible to obtain an oriented four-axis reinforced three-dimensional molding substrate. What
As the filament 1, is carbon fiber 3 and epoxy resin 4?
Was used. Then above
For example, epoxy resin is used as the matrix 2 on the molding substrate.
It is vacuum impregnated and heat-cured to obtain a high-efficiency product of another invention.
An energy absorbing composite material was prepared.

FIG. 3 is a displacement curve diagram showing a displacement change due to a load of a four-axis reinforced three-dimensional composite material when a test piece is cut out from the composite material produced as described above and a compression test is performed. In the figure, X indicates a region in which the entire composite material is deformed, and Z indicates a very large energy absorption behavior until the ultimate fracture point A is reached by compressive deformation while the obliquely oriented filaments slide with each other. At this time, the rigidity and strength of the material can be controlled by changing the orientation angle of the filament in the molding substrate. However, when the reinforcing material orientation angle is within ± 15 ° with respect to the external load axis, the micro-pattering of the molding base material abruptly increases and the sufficient energy absorption function cannot be exhibited, and the orientation angle is ± 60 to 90 °. Within the range, the deformation of the molding substrate is not sufficiently performed against an external load, and the sufficient energy absorbing function cannot be exerted.
That is, in order to achieve high energy absorption, one external negative
The filaments are three-dimensional within the range of ± 15 to 60 ° with respect to the load axis.
Must be obliquely oriented. In this case, the number of orientation axes of the filaments may be 3 to 9 as the molding substrate in which the filaments are three-dimensionally assembled, but 4 axes are required to increase the volume density of the molding substrate, and Considering isotropicity, 7 axes are desirable. Further, although carbon fibers were used as the reinforcing fibers in the above examples, other inorganic fibers or organic fibers may be used,
It goes without saying that a thermoplastic resin can also be used as the matrix. Table 1 shows the conventional two-dimensional reinforced composite material (laminate) and

[0010]

[Table 1]

The absorbed energy per unit volume of the 4-axis reinforced composite material (4A3D) is shown. For comparison, the direction connecting the opposite face centers of the cube (0 ° and 90 ° to the load axis)
Triaxially reinforced three-dimensional composite materials (3A3D) and 3A3D and 4A3D using molded substrates with filaments oriented in the (° direction)
The values of the 7-axis reinforced three-dimensional composite material (7A3D) using the molding base material in which the filaments are oriented in the combined direction are also shown. The energy absorption amount in this table is obtained by dividing the work amount corresponding to the area surrounded by the curve up to the maximum load point and the displacement axis in the load-displacement curve of FIG. 3 by the volume of the test piece, and the material Shows the energy absorption characteristics of. As can be seen from the table, the four-axis reinforced three-dimensional composite material exhibits high energy absorption characteristics, and a characteristic improvement of about 10 times is seen as compared with the conventional two-dimensional reinforced composite material.

Table 2 shows the vibration characteristic results of the four-axis reinforced three-dimensional composite material. 4 axis reinforcement used here

[0013]

[Table 2]

The three-dimensional composite material (4A3D) is obtained by vacuum-impregnating the molding substrate prepared in Example 1 with an epoxy resin having rubber elasticity. In the table, neoprene rubber and butyl rubber in the table are values of rubber materials that are generally used as damping materials. As can be seen from the results, 4A3D exceeds the rubber material in both damping characteristics and strength.

Table 3 shows a lattice-like porous material and a uniaxially reinforced composite material disclosed in the prior art publications.

[0016]

[Table 3]

It is a comparison of the load-bearing capacity with respect to the compressive force, and from the table it is possible to prove the superiority of the absolute strength required as a structural material for the composite material using the molding substrate of one embodiment of the present invention.

As described above, the present invention uses three-dimensionally combined filaments obliquely oriented within a range of ± 15 to 60 ° with respect to one external load axis. It is possible to obtain a multiaxially reinforced three-dimensionally molded base material for high energy absorption, which can obtain a composite material excellent in specific rigidity and specific strength applicable to a wide range of structural members. Also,
Invention Another invention is ± 15 with respect to one external load shaft.
Three-dimensionally combined lines that are obliquely oriented in the range of -60 °
Multi-axis reinforced three-dimensional molding substrate for high energy absorption
In addition, since the matrix resin is vacuum impregnated and cured,
High energy absorption composite material with excellent specific rigidity and specific strength
You can get it easily.

[Brief description of drawings]

FIG. 1 is a perspective view showing a multi-axially reinforced three-dimensionally shaped substrate for high energy absorption according to one embodiment of the present invention.
4 directions (multi-axis direction) while maintaining a predetermined angle with respect to 5 directions
The above-mentioned filaments of the above-mentioned molded substrate obtained by three-dimensionally obliquely orienting
FIG. 3 is a conceptual diagram of orientation of filaments showing the orientation direction of .

FIG. 2 is a partially enlarged sectional view of a filament according to an embodiment of the present invention.

FIG. 3 is a displacement curve diagram of a composite material using an embodiment of the present invention.

FIG. 4 is a perspective view of a conventional lattice-like porous structural member.

[Explanation of symbols]

 1 Line 2 Matrix 3 External load direction

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Atsushi Yoshizaki 8-1-1 Tsukaguchihonmachi, Amagasaki City Mitsubishi Electric Corp. Material and Device Research Laboratory (56) Reference JP-A-2-263835 (JP, A)

Claims (2)

(57) [Claims] 1. ± 15 to 6 with respect to one external load shaft
A multiaxially reinforced three-dimensional forming base material for high energy absorption, which is a three-dimensional combination of filaments obliquely oriented in the range of 0 °. 2. A range from ± 15 to 6 with respect to one external load shaft.
Three-dimensionally combined lines that are obliquely oriented in the range of 0 °
Multi-axis reinforced three-dimensional molding base material for high energy absorption
High energy produced by vacuum impregnation of matrix resin and curing
-Absorptive composite material.