JPH0453736A - Honeycomb sandwich board and its manufacturing method - Google Patents

Abstract

PURPOSE:To improve total thermal conductivity, make both the thermal expansion coefficients of skin and of honeycomb core equal to each other and consequently prevent product from deforming and contrive to stabilize its dimensions by a method wherein both the skin and the honeycomb core consisting of continuous carbon fiber reinforced carbon are made into an integral body by being bonded together. CONSTITUTION:Preform, which is prepared by thermosetting thermosetting resin- impregnated continuous carbon fiber cloth 2 under pressure and heat, is fired and carbonized. After carbon is filled in respective hollows of the carbonized preform, the carbonized preform is fired graphitized so as to produce ultra-thin skin. On the other hand, respective core parts 8, each of which is prepared by setting thermosetting resin-impregnated continuous carbon fiber cloth 4 under pressure and heat, are successively arranged so as to be symmetrically adjacent to one another in order to form preform by bonding the parallel parts of respective matching parts 10 with adhesive 7. Then, the preform is fired and carbonized. After the carbon 5 is filled in respective hollows of the carbonized perform, the carbonized preform is fired and graphitized so as to produce honeycomb core 6. Next, respective skins 1a and 1b are bonded onto and beneath the honeycomb 6 with adhesive 7 so as to be made into an integral body.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a honeycomb sandwich plate used in the construction of space equipment, etc., and a method for manufacturing the same.

[Conventional technology]

FIG. 5 shows a sectional view of an example of a conventional honeycomb sandwich plate of this type. lla and llb are respective skins made of continuous carbon fiber reinforced plastic, 12 is an aluminum honeycomb core, and 13 is an adhesive for bonding each skin 11a, llb and the core 12.

As for the manufacturing method of these, each skin 118° 11b is manufactured by impregnating a continuous carbon fiber cloth with epoxy resin and then heat-curing it by applying pressure and heat to produce an ultra-thin skin, and then forming an ultra-thin skin with an aluminum core. Adhesive 13 above and below 12
This type of honeycomb sandwich was manufactured by coating the adhesive and adhering it by applying pressure and heating.

[Invention tries to solve! ! Title]

This type of honeycomb sandwich board is used for the structures of artificial satellites, solar battery paddles, etc. During operation, it is affected by radiant heat from sunlight and heat generation from equipment, so it has poor heat dissipation. However, the honeycomb core of the conventional honeycomb sandwich board is made of aluminum with good thermal conductivity, but the skin is made of a thermosetting resin matrix. It is made of wood and has a thermal conductivity of 50 to 8.
It is relatively low at 0w/m and has a heat resistance of 100 to 15
Because the temperature was relatively low at 0°C, heat countermeasures such as heat sinks were required. In addition, since resin is used as a matrix during the honeycomb sandwich plate forming process,
The skin has a relatively low rigidity, and after being heat-cured and bonded, there is a problem that the skin may be bent or deformed due to the thermal contraction force of the aluminum honeycomb, which has a large coefficient of thermal expansion.

This invention was made in order to solve the problems of the conventional example as described above, and the skin and the Nicum core are made of the same material with high thermal conductivity to improve the overall thermal conductivity. The object of the present invention is to prevent deformation of the product and stabilize its dimensions by making the coefficient of thermal expansion the same, and to provide a method for manufacturing the same.

[Means for solving the problem] Therefore, the honeycomb sandwich board according to the present invention has the following features:
The above object is achieved by constructing the skin and the honeycomb core from continuous carbon fiber-reinforced carbon and integrating them by adhesion.

In addition, the manufacturing method for the skin of this type of honeycomb sandwich board involves a process of weaving continuous carbon fibers into a cloth, impregnating this cloth with a thermosetting resin and pressurizing it.

A step of thermosetting and molding the preform by heating, and a step of molding the preform at 1,000 to 2,000°C.
Carbonization is achieved through carbonization by embedding carbon in each cavity, followed by firing and graphitizing this process until the cavities are virtually eliminated, creating a continuous carbon fiber reinforced carbon pole. On the other hand, as a manufacturing method for the honeycomb core of this No. 1 honeycomb sandwich board, a continuous carbon fiber cloth is impregnated with a thermosetting resin, and the tips of these irregularities are formed by impregnating a continuous carbon fiber cloth with a thermosetting resin. A step of molding a core part having a continuous uneven part and a parallel part at the tip by bringing it into contact with a mold having parallel parts on the part, pressurizing it, heating it and hardening it. forming a preform by sequentially arranging the parallel parts of the uneven parts so as to be adjacent to each other, and carbonizing the preform by firing the preform at 1,000 to 2,000 °C; A process of manufacturing a honeycomb core of continuous carbon fiber reinforced carbon by embedding carbon in each cavity and firing it, and repeating this process until the cavity is substantially eliminated and graphitizing it, and a process of manufacturing a honeycomb core of continuous carbon fiber reinforced carbon. It is an object of the present invention to provide a method for manufacturing a honeycomb sandwich plate, which is characterized by comprising a step of integrating the honeycomb core with an adhesive.

(Function) The honeycomb sandwich plate according to the present invention having the above-described configuration and manufacturing method has the following effects: the skin and the honeycomb core are made of the same continuous carbon fiber reinforced carbon.
Thermal conductivity of skin and honeycomb core is approximately 100-2
00 W/m, the heat dissipation properties are improved, and the heat resistance is also improved to about 500 to 1500°C. Furthermore, the coefficient of thermal expansion of the honeycomb core made of the same material as the skin is
Compared to conventional aluminum honeycomb, it has been significantly reduced, and in terms of rigidity, the elastic modulus is approximately 10.000 to 2.
It is possible to obtain a honeycomb sandwich plate with good dimensional stability with an improved glol of 0.000 and less distortion during molding.

(Example) The present invention will be explained below based on examples.

(Structure) FIG. 1 is a partially cutaway perspective view of a skin of an embodiment of a honeycomb sandwich plate according to the present invention, and FIG. 2 is a sectional view thereof. la and lb are skins made of continuous carbon fiber cloth 2 as a substrate, continuous carbon fiber cloth 2 as a matrix, and carbon 3 as a matrix, and 6 is a skin consisting of continuous carbon fiber cloth 4 as a base material and carbon 3 as a matrix. It is a honeycomb core made of carbon 5. 7
indicates a heat-resistant adhesive such as glass paste (manufacturing method) This honeycomb sandwich plate is manufactured by the following steps.

First, each skin la, lb is 1.000 to 12.00
A continuous carbon fiber cloth (cloth) 2 is manufactured by weaving continuous carbon fibers with zero filler into a cloth, and then this cloth 2 is impregnated with a thermosetting resin such as a phenol resin or an epoxy resin, and then pressurized and heated. A preform is manufactured by heat curing. Next, add this preform to 1,000
Carbonize by firing at ~2,000°C, then bury/fill carbon into each cavity and fire, then turn green in this process and fill with carbon until these cavities are virtually gone. By graphitizing continuous carbon fiber reinforced carbon,
．． An ultra-thin skin of about 2 to 1.0 ms is manufactured.

On the other hand, the honeycomb core 6 is made by impregnating the continuous carbon fiber cloth 4 with a thermosetting resin such as phenol resin or epoxy resin, and having continuous uneven parts with the same pitch, and each parallel part at the tip of these uneven parts. By applying pressure, heating, and hardening in contact with a mold provided with a mold, continuous uneven portions 9 are formed as shown in the plan view of the core component in FIG. A core part 8 with a parallel part 10 is molded. In addition, in FIG. 3, 19 indicates the thermosetting resin to be impregnated.

Next, as shown in the plan view of the honeycomb core in FIG. The preform is molded and manufactured by bonding.
Next, this print form is heated to 1,000 to 2,000℃.
After firing and carbonizing, each cavity is buried/filled with carbon 5 and fired, and this process is repeated to graphitize by firing until these cavities are substantially eliminated. A honeycomb core 6 of continuous carbon fiber reinforced carbon is manufactured. Next, the skins la and lb are bonded to the top and bottom of the honeycomb core 6 using an adhesive 7 to integrate them. The honeycomb core sandwich board product of this example is manufactured by the manufacturing method described above.

Through this manufacturing method, the skin has relatively low heat dissipation properties (heat transfer coefficient of about 50-80 W/m), rigidity, heat resistance (about 100-150 degrees Celsius), and relatively high thermal deformability of the conventional example. (Compared to the large coefficient of thermal expansion of aluminum honeycomb core, about 23 to 25 .000~20,000g/as”
).

Honeycomb sandwich plates are obtained which have high temperature resistance (approximately 500 DEG to 1,500 DEG C.) and extremely low thermal deformability (skin/core material is identical and low coefficient of thermal expansion is approximately 1 to -IXIO-').

(Other Embodiments) In the above embodiments, each skin material and the honeycomb core material were made of the same continuous carbon fiber reinforced carbon cloth based material according to the principles of this invention. However, as an application example of this invention, Due to the operating environment conditions of this type of honeycomb sandwich board, within the allowable range of overall heat transfer coefficient/thermal expansion coefficient, only the above materials are used for each skin material, and the honeycomb core is a conventional aluminum honeycomb core. Of course, there is no problem in doing so.

〔Effect of the invention〕

As explained above, according to the present invention, compared to the conventional skin made of continuous carbon fiber reinforced plastic, which has relatively low heat dissipation properties, rigidity, and heat resistance, the present invention has good thermal conductivity, high rigidity, and A skin with improved heat resistance has been adopted, and the honeycomb core has been replaced with a fiber-reinforced amorphous honeycomb core with an extremely small coefficient of thermal expansion, instead of the conventional aluminum honeycomb core with a high coefficient of thermal expansion, resulting in increased rigidity and heat resistance for heat dissipation properties. A honeycomb sandwich plate with excellent properties can be obtained, and the skin/core can be heated! Since they are made of the same material with a small tensile modulus, a honeycomb sandwich plate with little thermal distortion during molding and excellent thermal dimensional stability is produced.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of a honeycomb sandwich plate according to the present invention, FIG. 2 is a sectional view thereof, FIG. 3 is a plan view of a core component, FIG. 4 is a plan view of a honeycomb core, and FIG. The figure is a sectional view of an example of a conventional honeycomb sandwich plate. 1a and lb are continuous carbon fiber reinforced carbon skins, 2.4 is continuous carbon fiber cloth, 3.5 is carbon 56 is continuous carbon fiber reinforced carbon honeycomb core, 7 is adhesive, 8 is core part,
9 shows an uneven portion of the core component, and 10 shows a parallel view of the uneven portion of the core component. Note that in each figure, the same reference numerals indicate the same components.

Claims (2)

[Claims] (1) The skin plate and honeycomb core material of the honeycomb sandwich board are composed of continuous carbon fiber reinforced carbon with continuous carbon fiber cloth as a base material and carbon as a matrix, and the skin plate and honeycomb core are joined and integrated. A honeycomb sandwich board that features: (2) The manufacturing method for the skin of the honeycomb sandwich board involves a process of weaving continuous carbon fibers into a cloth, and a process of impregnating this cloth with a thermosetting resin and thermosetting it by applying pressure and heating to form a preform. Then, this preform is carbonized by firing at 1,000 to 2,000°C, and carbon is buried in each cavity and fired, and this process is repeated and fired until these cavities are substantially eliminated. On the other hand, in order to manufacture the honeycomb core of this honeycomb sandwich board, a continuous carbon fiber cloth is impregnated with a thermosetting resin to form a continuous carbon fiber reinforced carbon skin. A core having concavo-convex portions and parallel portions at the tips of these concavo-convex portions is made by contacting it with a mold having parallel portions at the tips of these concavo-convex portions, applying pressure, heating, and hardening. The process of molding the parts;
A step of forming a preform by sequentially arranging these core parts adjacent to each other and bonding the parallel parts of the uneven parts to each other;
Continuous carbon fiber reinforcement is achieved by firing at 2,000°C to carbonize, then embedding carbon in each cavity and firing, repeating this process until the cavities are virtually eliminated and graphitizing. A method for manufacturing a honeycomb sandwich board, comprising the steps of manufacturing a carbon honeycomb core and integrating the skin and the honeycomb core with an adhesive.