JPS59112028A - Carbon fiber coated with silica compound and ceramic reinforced therewith - Google Patents

Abstract

PURPOSE:To prepare the titled carbon fiber having high wettability and corrosion resistance to ceramics, and suitable for the fishing rod, golf club shaft, industrial materials, etc., by attaching a specific amount of a powdery silica compound to a carbonaceous filber, and heat-treating the fiber at high temperature in nitrogen atmosphere. CONSTITUTION:A powdery silica compound (preferably Si, SiO2, Si3N4, SiC, etc. having a particle diameter of 1-10mu) is attached to carbonaceous fiber at a volume ratio of 10-500%. The fiber is heat-treated at 800-1,300 deg.C in nitrogen atmosphere to obtain the objective coated carbon fiber. The fiber is shaped to a desired shape, and treated at >=1,300 deg.C under pressure to obtain a reinforced ceramic.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to carbon fibers having good wettability to ceramin and resin and good corrosion resistance when producing carbon fiber reinforced ceramics.

Composite materials reinforced with carbon fiber are currently used not only as sports materials such as fishing rods and golf shafts, but also as industrial materials such as structural materials for aircraft and drive shafts for automobiles.

However, the matrix that makes up the carbon fiber reinforced composite material, which is currently being developed, is difficult to handle.
Plastics are the mainstream because of their ease of molding, and no significant progress has been made in the development of carbon fiber-reinforced composite materials with a metal matrix. The reason for this is that when carbon fibers come into contact with high-temperature metals, the surface of the carbon fibers reacts and turns into metal carbide, which significantly changes the carbon fiber properties, and the wetting properties between the carbon fibers and these matrix components are insufficient. The present inventors completed the present invention as a result of studies aimed at improving these disadvantages of carbon fibers.

That is, in the present invention, carbon fibers to which 10 to 500% of the fibers are attached by volume of silica compound powder are heated in nitrogen for 80 minutes.
This is a method for producing carbon fiber characterized by heat treatment at 00-1300°C.

The silica compounds used in the present invention are S + , S 1
02 rSi3N, SiC, etc. are solid substances at room temperature, and when carrying out the present invention, the particle size of these compounds is 200 mesh or less, preferably 1.
It is best to use a fine powder of ~10 μrn.

The carbon used in carrying out the present invention is made by flame-retardantly treating organic fibers such as acrylonide IJ fibers and cellulose fibers, flame-retardantly treated coal-based and pitch-based fibers, and flame-retardant yarns of these fibers that are further heated at high temperatures. It includes treated carbonized yarn and graphitized yarn.

The method for applying the silica compound powder to the flame-distributing carbon fibers includes a method of attaching a silica compound to a binder coated carbon fiber, or a method of attaching a silica compound to a carbon fiber coated with a binder, or a method of attaching a silica compound to a carbon fiber coated with a binder; A method may be used in which the silica compound powder is dispersed in a binder bath liquid of polysaccharide, polyacrylic acid, etc. to form a slurry, and then the carbonized thread is dip-coated.

The present invention is as described above (i.e., carbonized yarn having a specific amount of silica compound particles attached thereto is heated to 800 to 1300 mL in nitrogen atmosphere
By heat-treating at a temperature of 800°C, it is possible to obtain the desired carbon fibers, especially carbon fibers coated with one element that can be tinized. However, if the treatment temperature is lower than 800°C, the carbon fibers with the desired properties cannot be obtained. cannot, while 1
When a high temperature exceeding 300°C is used, it is sometimes observed that the silica compound, the silica compound, the carbonaceous fiber, and the silica compound partially react, and the properties of the reinforcing fiber may deteriorate, so this is not preferred. do not have.

The silica compound-coated carbon fiber produced according to the present invention is placed directly in a mold such as a mold, and heated under pressure at a temperature of 1,300°C or higher. It has a major feature in that it can produce carbon fiber reinforced ceramics as a matrix component, and by allowing magnesium compounds such as MgO and Mg3N2 to coexist during sintering, it is possible to create ceramics with even better strength properties. can do.

The present invention will be explained in more detail with reference to Examples below.

Example 1 Flame-resistant yarns obtained by oxidizing acrylic fibers KM and S
+ 100 parts, carboxymethyl cellulose soda 1
and 150 parts of water for 5 minutes. The fibers were heated in nitrogen at 1200° C. for 20 hours to obtain silica compound-coated carbon fibers.

Furthermore, this fiber was heated at 1600℃ and 200 to 9/c4,
A carbon fiber reinforced ceramic was obtained by hot pressing for 3 hours.

Example 2 5 il of flame-resistant yarn obtained by oxidizing acrylic fiber
oo part, sodium alginate 1 part, acrylic acid polymer 0
1 part and 200 parts of water were mixed for 5 minutes.

The fibers were heated in nitrogen at 1200° C. for 20 hours to obtain silica compound-coated carbon fibers. Furthermore, this fiber is added to 160
A carbon fiber reinforced ceramic was obtained by hot pressing at 0 °C and 200 K7/aa for 3 hours.

Patent applicant Patent attorney representing Mitsubishi Rayon Co., Ltd. 1) Toshite Mura's amendment (spontaneous) June 3, 1980 Mr. Kazuo Wakasugi, Commissioner of the Japan Patent Office■ Indication of the case 1988 Patent application No. 218331, Invention Name of silica compound-coated carbon fiber and reinforcing ceramic using the same, relationship with the person making the third amendment Patent applicant: 2-3-19 Kyobashi, Chuo-ku, Tokyo (603) Kanazawa, President and Director of Mitsubishi Rayon Co., Ltd. Shu, 34 Agent, 2-8-1, Toranomon, Minato-ku, Tokyo Contents of the 7 Amendment (1) Page 4 of the specification, lines 8 to 9: “Silica compounds, 7-liquid compounds, carbonaceous fibers, and silica compounds.” corrected J to "silica compound and carbon fiber".

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Claims (2)

[Claims] (1) Powdered silica compound is layered with a volume ratio of 10 to 500% on carbonaceous fibers, and 800 to 1
Silica compound coated carbon fiber heat treated at 300°C. (2) Powdered silica compound is attached to carbonaceous fibers at a volume ratio of 10 to 500%, and 800-1
Heat treated at 300°C and held in a predetermined shape,
Reinforced ceramic processed at temperatures above 1300℃ under pressure.