JPS61242963A - Ceramic member and manufacture - 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 [Industrial Application Field] The present invention relates to a method of manufacturing a ceramic member, and particularly to a method of manufacturing a ceramic member reinforced with heat-resistant M1#1.

[Prior art] In recent years, non-oxide ceramics such as silicon nitride, silicon carbide, and sialon, as well as so-called new ceramics such as aluminum oxide and zirconium oxide, have been rapidly attracting attention as high-temperature, high-strength structural materials, and much research and development has been carried out. being done.

These ceramics have many uses as gas turbine blades and combustors, diesel engine cylinders and pistons, and other high-temperature mechanical parts.

However, as is well known, ceramics are brittle materials, and even with the new ceramics described in section H, cracks propagate faster than metal materials, and even the slightest defect can destroy them.
Lacking reliability.

Furthermore, ceramic products are usually manufactured by forming a ceramic powder raw material by an appropriate method and then sintering it, but this sintering usually requires a sintering aid. As a result, this sintering aid reduces the high temperature strength of the entire product. In other words, although ceramics themselves inherently have high strength even at high temperatures,
A large amount of low-melting-point sintering aid components gather at grain boundaries, and for this reason the strength of the resulting product decreases at high temperatures.

On the other hand, in recent years, vapor deposition methods such as CVD and PVD have been introduced as completely new ceramic manufacturing methods.The CVD method, which is used in the field of surface treatment as a means of forming thin films, produces ceramics with extremely dense structures. Moreover, since it does not go through a sintering process, there is no need to mix a sintering aid, and therefore the strength of the resulting product does not decrease even in a high temperature range.

[Problems to be Solved by the Invention] According to the vapor phase deposition method such as the CVD method, since a sintering aid is not required, a product having high-temperature strength of the ceramic body can be obtained, so it is suitable for the production of ceramic coatings. is extremely advantageous.

However, when manufacturing thick film members by the CVD method, as shown in Figure 2, ceramic columnar crystals 2 develop in the direction perpendicular to the base l, and although high strength in the vertical direction is achieved, horizontal There is a problem that the strength in the direction becomes low.

In addition, the CVD method has a relatively slow ceramic production rate, with a film production rate of about 20 to 30 ILm/hr, so it takes a long time to form a normal structure, making it not industrially advantageous. It has the disadvantage that it is not.

[Means for Solving the Problems] According to the present invention, a ceramic member is obtained by wrapping heat-resistant fibers around a base body and attaching the fibers to the base body, and then depositing ceramics on the surface of the base body in a vapor phase.

[Function] According to the present invention, a ceramic member reinforced by heat-resistant fibers attached to a base is provided. Furthermore, the development of columnar crystals in the vapor-deposited layer is suppressed, and this also increases the strength of the ceramic in the in-plane direction. Moreover, since the amount of vapor phase deposition is reduced by the volume of the heat-resistant fiber, the manufacturing time is shortened.

Therefore, it becomes possible to efficiently produce thick ceramic layers with extremely high strength by vapor phase deposition.

[Examples] Examples of the present invention will be described in detail below with reference to the drawings.

FIGS. 1(a) to 1(C) are schematic cross-sectional views illustrating a method of manufacturing a ceramic member according to an embodiment of the present invention.

In the present invention, as shown in FIG. 1(a), the base 11
Heat-resistant fibers [12 are attached by winding or other methods, and then ceramics are deposited on the fiber attachment surface 11a of the base 11 by a vapor phase deposition method such as a CVD method.

When ceramics are deposited on the fiber bonding surface 11a of the base 11 by the CVD method, first, at least the surface 11a of the base 11 is heated to a precipitation temperature range for the CVD reaction.

The heating method is not particularly limited, but if the base 11 has a simple shape or is conductive, high-frequency induction heating or the like with a simple device configuration is advantageous.

As a heating method, an external heating method of heating from the outside of one reaction container can also be adopted.

The fiber attachment surface 11a of the substrate 11 heated in this way
As shown in Fig. 1(a), CVD reaction gas is supplied and C
A CVD reaction is carried out to deposit a CVD reaction precipitate 13 on the surface of the substrate 1 (see FIG. 1(b)).

The amount of the CVD reaction precipitate 13 can be easily adjusted by adjusting the supply of the CVD reaction gas or the heating time.

After depositing the CVD reaction precipitate 13 to a desired thickness,
The surface is polished by i1 to obtain a member in which a layer of CVD reaction precipitate 13 is formed on the substrate ti, as shown in FIG. 1(C).

The substrate 11 may be integrated with the CVD reaction precipitate 13 as it is as a product as shown in FIG. d
) The base body 11 may be separated and removed to produce a product.

In such a method of the present invention, there is no particular restriction on the material of the substrate 11, and metals, ceramics, etc. can be used. However, if the substrate 11 is used with the substrate 11 attached after the CVD reaction, In order to prevent thermal stress from being applied due to high temperatures, it is preferable that the material of the nozzle 11 has a coefficient of thermal expansion comparable to that of the CVD reaction precipitate to be precipitated.

On the other hand, when the substrate 11 and the CVD reaction precipitate are separated after the CVD reaction, the substrate 11 is made of a material that does not substantially react with the CVD reaction precipitate and has a coefficient of thermal expansion different from that of the CVD reaction precipitate. By selecting such a material, which is preferably made of
1 and the CVD reaction precipitate 13, a light mechanical impact is applied to the vicinity of the interface between the precipitate 13 and the substrate 11, or
By heating or cooling the vicinity of the interface, it is possible to easily remove it by peeling it off.

Note that if the base 11 is made of a combustible material, it is possible to oxidize and eliminate the base 11. Furthermore, a material that can be broken and removed, such as a sand mold in casting, may be used, or it may be removed by mechanical processing.

As a method for attaching the heat-resistant edge fi12 to the base body 11, the most convenient and advantageous method is to wind the highly heat-resistant fiber [112] around the base body 11. In addition, there is a heat-resistant edge fi on the base 11.
12 may be adhered by any suitable method.

The heat-resistant fibers may be of any kind as long as they can withstand the CVD reaction temperature and the usage temperature of the resulting product components.
Specific examples include fibers such as SiC, W, and Mo.

In addition, as the ceramic to be precipitated, MgO1SiC
, Si3N+, AJL203. Examples include Sialon.

In addition, in the above explanation, the method of manufacturing a flat member by adhering highly heat resistant fibers to the surface of a flat substrate and depositing a CVN reaction precipitate on this surface was explained. In the present invention, as shown in FIGS. 3 to 5, a three-dimensional member can also be manufactured by processing the shape of the base 11 to match the shape of the LI member.

That is, in the example shown in FIG. 3, as shown in FIG. 3(a), a heat-resistant fiber 12 is wound around a rectangular base 11, and a CVD reaction gas is applied to the outside as shown by the arrow in the figure. A CVD reaction precipitate 13 was deposited around the substrate 11 as shown in FIG. 3(b). By removing the base 11, this can be made into a hollow fiber-reinforced ceramic member as shown in FIG. 3(C).

In the example of FIG. 4, it is as shown in FIG. 4(a).

A heat-resistant edge fi 12 is wound around the side surface of a cylindrical base 11, a CVD reaction gas is supplied to this, and CVD reaction precipitates 13 are deposited around the base 11 as shown in FIG. 4(b). It is. By removing the base 11, this can also be made into a hollow fiber-reinforced ceramic member as shown in FIG. 4(C).

FIG. 5 explains the case of manufacturing gas turbine blades by the method of the present invention. As shown in FIG. 5(a), a heat resistant The fiber 12 is wound, a CVD reaction gas is supplied, a CVD reaction precipitate 13 is precipitated as shown in FIG. It is.

Note that the heat-resistant edge fi12 may be provided densely in areas that require high strength, and loosely in areas that do not require particularly high strength, or may be wound in two or more layers on the base. In this case, for example, as shown in FIG. 6(a), by crossing the winding directions of adjacent heat-resistant fiber winding layers, a ceramic member with higher strength (see FIG. 6(a)) may be created. (b)) can be produced.

Further, the adhesion of the fibers to the substrate and the CVD reaction are repeated several times, that is, for example, heat-resistant fibers are further applied to the surface 13a of the CVD reaction precipitate 13 of the ceramic member shown in FIG. 1(C) or (d). It is also possible to provide a CVD reaction gas and to stack CVD reaction deposits.

Although the CVD method is employed in the explanation of item 1-, other vapor phase deposition methods such as the PVD method may also be used in the present invention.

[Function] The heat-resistant fibers attached to the substrate provided reinforcement and suppressed the development of columnar crystals in the vapor-deposited layer. A ceramic layer with extremely high strength can be obtained. Moreover, since the vapor deposition area is reduced by the volume of the heat-resistant fiber, the manufacturing time is shortened.

Therefore, it becomes possible to efficiently produce a thick film layer of Ceramic-2 with extremely high strength by the vapor phase deposition method.

[Example] The present invention will be explained in more detail below using examples.

Example 1 A ceramic member shown in FIG. 4(C) was manufactured according to the manufacturing method of the present invention.

First, a graphite rod (φ30 mm x 120
Walk (mm) as shown in Figure 4(a).
'l' (uniform diameter 0.02mm) is wound around the top and heated by an external heating method, the temperature is detected by a thermocouple set at the end of the base, and the temperature of the heated part is set to 1300-1400mm.
The temperature was maintained at 00°C.

Then, 5ICfL4/C was applied to the substrate ti as a CVD gas.
Supply H4/H2, CVD reaction precipitate (SiC)
After depositing 13, the gas supply was stopped.

Thereafter, the lli body 11 was removed by machining.

The obtained SiC member was a cylindrical member having a hollow portion in the shape of the base 11, but it was manufactured in an extremely short time by the method of the present invention and had extremely high strength.

[Effects] As described in detail below, according to the method for manufacturing a ceramic member of the present invention, the resulting ceramic member has extremely high strength, durability, and reliability due to the strength-improving effect and columnar crystal suppressing effect of the heat-resistant fiber. It will be expensive. Moreover, the outer surface of the manufactured ceramic member becomes extremely dense.

Further, by selecting the shape of the base, a ceramic member of any shape can be manufactured. Furthermore, the amount of ceramics deposited is reduced due to the presence of highly heat-resistant fibers.
Production efficiency is also extremely high.

[Brief explanation of drawings]

1(a) to 1(d) are schematic cross-sectional views illustrating the manufacturing process of a ceramic member according to an embodiment of the present invention;
The figure is a cross-sectional view showing columnar crystals obtained when a thick film is formed by the CVD method.
a) to (c) and FIGS. 5(a) and (b) are respectively perspective views and FIGS. 6(a) and (b) illustrating the manufacturing process of a ceramic member according to another embodiment of the present invention. ) is a sectional view illustrating another embodiment of the present invention. 11...Base, 12...High heat resistant fiber, 13...CVD precipitate. Agent Patent Attorney Tsuyoshi Shigeno Figure 1 (c) Figure 2 CVO reaction gas (b)
cvorL corresponding gas Fig. 5 Fig. 6 (a) (b)

Claims (1)

[Claims] (1) A method for producing a ceramic member, which comprises the steps of: wrapping heat-resistant fibers around the surface of a substrate to attach them; and then vapor-depositing ceramics on the fiber attachment surface of the substrate to fill in gaps between the fibers.