JPS59223284A - Manufacture of carbon material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a carbon material in which crystal growth during sintering is controlled.

Conventionally, many proposals have been made as composite materials of carbon materials. For example, it has been proposed that a mixed composition of various carbon materials is fired at a constant temperature and pressure-molded to form a film, sheet, wire, rod, or sometimes powder or granule. These fired mixed compositions are used after being fired at a constant temperature. Further, mixed carbon materials are often based on carbon powder, tar, and organic compounds or carbides. These materials have a standard problem of having uniform composition and uniform crystals as a whole, and a solution has been obtained. However, in order to achieve the intended use of carbon materials, even during the final firing of the sintered product, it is necessary to partially delay or prevent graphitization, and to reduce the size of the crystals in the graphitized parts. It is necessary to vary the grain size and control the grain size.

For the above purpose, the present invention provides a carbon composition (
Hereinafter, it will be referred to as A carbon composition. ) or the surface of a material that has been primarily fired at a temperature below the graphitization temperature (hereinafter referred to as B carbon composition) is coated with a metal or a carbon material with a different graphitization temperature, and then further heated at the required temperature. To provide a method for producing a carbon material in which a carbon composition (hereinafter referred to as a final carbon composition) in which the graphitization is different in many parts and the crystal size is controlled in many parts is obtained by firing at K. It is something.

The metal used to obtain the final carbon composition may be activated metal palladium, platinum, titanium, copper or other metals. Furthermore, the carbon material used to obtain the final carbon composition is a resinous carbon material that is extremely difficult to graphitize (carbonize). As the resin, polymethyl methacrylate, polyethylene, polyester, or other resin is used. In order to use carbon produced from such a resin that is difficult to graphitize, the amount of resin to be mixed and contained is at least 5% at the minimum and about 60% at the maximum. By using this method, extremely high practical effects can be obtained.

Next, some embodiments will be described.

Example 1゜ Petroleum coke is made of A carbon composition, and when this petroleum coke and tar are mixed, 80 yen of petroleum coke and 1 tar are mixed.
After mixing 10% of 0'lpK polyethylene/glassy carbon (20μ grains) to form a coating layer of polyethylene/glassy carbon on the surface of petroleum coke,
Primary firing was performed at 1200°C under Kf/cj pressure, and then 2
The final carbon composition was formed by sintering at a sintering temperature of 2100° C. for 3 hours under a pressure of 0.00 Kf/m. This product has a specific gravity of 1.85, a shore hardness of 54, and a bending strength of 960 Ky/n.
d, compressive strength 1860 Kf/di, tensile strength 1100
Kr/csf, specific resistance was 1100 μΩ.

Example 2 92 degrees of petroleum coke and 8 degrees of tar were thoroughly mixed, and this was primarily fired at 1200° C. to produce a rod-shaped B carbon composition. This shape had a diameter of 10 mm and a length of 100 mm, and was used as a base material.

Activated palladium is deposited on the surface of the substrate as a coating layer approximately 200 angstroms thick.

Next, it was heated to 2600° C. under a pressure of 250 Kp/cn to form a rod-shaped molded body to form a final carbon composition. A portion of the metal is dispersed and diffused within the carbon composition, sufficiently reinforcing and adhering the coating and the inner layer.

This item has a specific gravity of 1.91 and a bending strength of 980 Kf/cd.
l, compressive strength 2100Kf/ad, elastic modulus 1560K
p/c! I, and the specific resistance was 1000 μΩα.

Example 3゜In the case where platinum, titanium, copper, iron, chromium, tungsten, molybdenum, and rare earth elements were used as metals instead of palladium used in Example 2, similar to Habo,
Good strength and specific resistance values were obtained.

Example 4 When polyethylene, polystyrene, polyester, or polycarbonate was used as the resin for producing the 4° glassy carbon, good strength and resistivity values were obtained similar to those shown in Examples.

Example 5゜The results of sintering the 20 pieces of Example 2 described above by applying pressure from three orthogonal directions, X, Y, and 2, show that the strength and resistivity values are as good as those of Example 2. As a result of many experiments, the amount of metal or carbon composition coated on the base material to obtain a compressive strength of about 3200 Ky/cj or more is used to be at least about 5% or more and up to about 60%. I was able to do that.

In addition, the sintering temperature is selected to be suitable for graphitizing and controlling the crystal size.

As already explained, the present invention uses carbon having different graphitization temperatures as a base material to form a film, a sheet, a powder, a rod, a cube, a wire, a fibrous material consisting of a wire, etc. This is because the Nishida carbon composition or the B carbon composition is coated with a resin or a high carbon organic compound or metal that has carbon that has a different graphitization temperature or is difficult to graphitize, and is then sintered. By controlling the graphitization of the coating layer, it is possible to delay the graphitization of some parts, create parts that do not convert to graphite, and control the size of the crystals when they become graphite. The molded body of the final carbon composition has good strength and resistivity, and has a great practical effect in the production of various purpose products.

Claims (1)

[Scope of Claims] 1. A coating layer of a carbon composition or metal having a graphitization temperature different from that of the base material is formed on the surface of a base material of a carbon material before firing or a primary fired carbon material performed at a temperature below the graphitization temperature. 1. A method for producing a carbon material, characterized in that the carbon material is then sintered under controlled heating and pressure. 2. A carbon material as described in the first claim, characterized in that the base material is a thin plate, powder, or fiber, and the surface is coated with a carbon composition or metal, and then the required amount is mixed and sintered. Production method.