JPH01321068A - Production of fiber composite member - Google Patents

Abstract

PURPOSE:To prevent the development of non-filling part of molten metal in fiber formed body and to surely make composite of both materials by opening engaging hole in a plate member, engaging and fixing the engaging projected part in the fiber formed body into the engaging hole and casting molten metal. CONSTITUTION:The engaging hole 5 is opened at position, where the fiber formed body 4 in the plate member 1 is closely stuck, and also the engaging projected part 4b is formed at the position corresponding to the engaging hole 5 in the fiber formed body 4. Then, by engaging the engaging projected part 4b with the engaging hole part 5, the molten metal 14 is cast under fixed condition of the fiber formed body 4 to the plate member 1. In this time, air in the fiber formed body 4 is flowed out to gap between the plate member 1 and a core mold 6 through the engaging projected part 4b and the engaging hole 5, and the molten metal 14 is penetrated to the whole fiber formed body 4 to make composite of the casting metal and the fiber formed body.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a fiber composite member, and in particular, a method for manufacturing a fiber composite member by casting a plate member and a reinforcing fiber molded body in close contact with the plate member in molten metal. It relates to a manufacturing method.

[Prior art]

Conventionally, various types of fiber reinforced metals (FRM), which are composites of reinforcing fibers such as alumina in aluminum or aluminum alloys, have been put into practical use. When manufacturing a fiber composite member made of the above-mentioned fiber-reinforced metals, reinforcing fibers such as alumina and silicon carbide are mixed with an inorganic binder such as silica in advance to form a molded body into a predetermined shape, and this fiber molded body is placed in a mold. A molten metal is poured into the container, and the molten metal is solidified under pressure to produce a fiber composite member.

In order to obtain a fiber composite member with the desired performance, it is necessary to maintain the reinforcing fiber material in a predetermined shape, density, and orientation state, and then place it in a mold and pour the molten metal into it. Japanese Patent Publication No. 62-38412 discloses that the reinforcing fiber material is formed into a predetermined shape, density, and orientation state by various methods, and is immersed in oil in an inorganic binder slurry, then dried and solidified to obtain a predetermined fiber molded article. A method for manufacturing a fiber composite member by forming a fiber molded article into a molded article and casting the fiber molded article is described.

On the other hand, the applicant has filed an earlier application (Japanese Patent Application No. 61-23928).
When manufacturing the rotor housing of the rotary piston enon by casting, insert material is placed in the predetermined position precisely and efficiently to improve the fatigue strength and thermal shock strength of the area around the plug hole of the rotor housing. To assemble it, a sheet metal formed into a trochoid shape was placed in a mold, and an insert material with excellent heat resistance and heat transfer properties was positioned and pressed into the sheet metal at the tip of the cast-out pin that forms the plug hole. We proposed a method of casting in the state.

[Problem to be solved by the invention]

In the method according to the above-mentioned application of Hikari, as shown in FIG.
A cast-out pin 1 for forming a plug hole is placed on the outer peripheral surface of the
1 and 3 are fitted into the fitting hole 100 of the fiber molded body 104 to position the fiber molded body 104 and press it against the sheet metal 101, and in this state, the gold rJS molten metal 114 is cast into the casting cavity. When manufacturing fiber composite members, the following problems arise.

That is, at the initial point of time when the molten metal 114 is cast, the molten metal 114 fills around the fiber molded body 104, and thereafter the pressurized molten metal 114 penetrates into the inside of the fiber molded body 104. At this time, the volume ratio of the reinforcing fiber material in the fiber molded body 1'04 is about 15 to 25%,
Since the fiber molded body 104 contains a lot of air,
Although the air contained in the fiber molded body 104 is pressurized by the molten metal 114 that permeates from the surroundings, since no passage is provided for the air to escape, the sheet metal 10
The molten metal 114 remains in the center of the fiber molded body 104 facing the fiber molded body 104, and a non-composite part 115 is formed without being filled with the molten metal 114. In this state, the molten metal 114 solidifies. Not only will that portion not be composited with the cast metal, but the bonding between this composite material and the sheet metal 101 will be incomplete. In other words, it is not possible to manufacture a fiber composite member (rotor housing) having the desired performance.

An object of the present invention is to provide a method for manufacturing a fiber composite member that allows the entire fiber molded body to be composited with cast metal and that can reliably support and position the fiber molded body.

[Means to solve the problem]

The method for manufacturing a fiber composite member according to the present invention involves going into a casting cavity, placing a fiber molded body in close contact with a plate member that is placed in contact with the inner surface of a mold and being cast. When manufacturing a fiber composite member by pouring molten metal into the plate member, an engaging hole is opened in a portion of the plate member where the fiber molded body comes into close contact, and an engaging hole is opened in a portion of the plate member that corresponds to the engaging hole of the fiber molded body. An engaging convex portion is formed, and the molten metal is poured in a state in which the fiber molded body is fixed to the plate member by fitting the engaging convex portion into the engaging hole.

[Effect]

In the method for manufacturing a fiber composite member according to the present invention, the engagement convex portion of the fiber molded body is fitted into the engagement hole opened at the portion of the plate member where the fiber molded body is in close contact with, and the fiber molded body is fixed to the plate member. Since the molten metal is poured into the fibrous molded body, the air inside the fibrous molded body escapes to the outside through the engagement convex portion and the engagement hole of the fibrous molded body. It is possible to fill the entire fiber molded body into a composite.

Since the fiber molded body can be positioned and fixed to the plate member by engaging the engagement convex portion with the engagement hole, the means for supporting and fixing the fiber molded body can be omitted or miniaturized.

〔Effect of the invention〕

According to the method for manufacturing a fiber composite member according to the present invention, as explained above, an engagement hole is opened in the plate member, and the engagement convex portion of the fiber molded body is engaged with the engagement hole and fixed. By simply adding this simple step, it is possible to prevent unfilled portions of molten metal from occurring within the fiber molded body and reliably composite the entire fiber molded body with the cast metal. Moreover, the fiber molded body can be positioned and fixed at a predetermined portion of the plate member by fitting the engagement convex portion of the fiber molded body into the engagement hole of the plate member, so that the means for supporting and fixing the fiber molded body can be used. It can be omitted or downsized.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

This example is an example in which the method for manufacturing a fiber composite member according to the present invention is applied to a method for manufacturing a rotor housing of a rotary piston engine.

As shown in Fig. 1, the rotor housing R is a cast product made of aluminum alloy, and the trochoid-shaped inner periphery portion has a structure in which sheet metal l made of high-strength steel is cast into aluminum alloy. A pair of upper and lower plug holes 2 and 3 for mounting a spark plug are formed in the middle portion of one side of the rotor housing R.

The portions of the plug holes 2 and 3 in the vicinity of the inner peripheral surfaces of the trochoids are exposed alternately to relatively low-temperature intake air and fire ignited by ignition, and thus receive severe thermal shock. Therefore, the rotor housing R manufactured by the manufacturing method according to this embodiment
Now, as shown in the figure, a molded body 4 of reinforcing fibers such as alumina short fibers is placed near the inner peripheral surface of the trochoid of the plug holes 2 and 3.
Incorporating it into a composite with aluminum alloy cast metal,
The adjacent portion is made of a composite material of fiber-reinforced aluminum alloy.

Next, a method for manufacturing the rotor housing R, which is the fiber composite member, will be explained.

First, a high-tensile steel plate with a plate thickness of 2.4 mm is used as the sheet metal 1, and one side of the plate is subjected to a sharpening process to form a wedge-shaped protrusion 1a of 1°9 mm. Next, the sheet metal 1 is formed into a trochoid shape by the method disclosed in Japanese Patent Publication No. 53-13574 with the wedge-shaped protrusion 1a on the outside, and the plug holes 2 and 3 of the formed sheet metal 1 are formed. Engagement holes 5 having a smaller diameter than the diameter of the inner end of the plug ball formed in the jet mesh 1 are formed at two locations corresponding to the above. However, the above sheet metal 1
2&Il to which the fiber molded body 4 described later is brought into close contact with one side of
The circular portion is not marked in order to improve the adhesion with the fiber molded body 4.

In parallel with the production of the above-mentioned jitomekuru 1, two sets of fiber molded bodies 4 are produced. In this case, a material made by uniformly mixing 95% alumina (AIJi) staple fibers with 5% by weight silica (SiO The fiber molded body 4 is produced by placing the fiber in a heated mold having the same shape and pressurizing it, and then performing powder molding.

Table 1 The shape of the above-mentioned fiber molded body 4 is as shown in FIG. Above sheet metal 1 in the center
The shape is formed by integrally protruding an engaging protrusion 4b that exactly fits into the engaging hole 5, and the thickness of the engaging protrusion 4b is the same as the thickness of the inconspicuous sheet metal 1. This is desirable.

Next, as shown in FIG. 2, the sheet metal 1 is tightly placed on the outer peripheral surface of the core mold 6, and
The fiber molded bodies 4 are attached to the parts of the casting cavity 8 corresponding to the vicinity of the inner ends of the plug holes 2 and 3, respectively. In this case, the engaging convex portion 4b is fitted into the engaging hole 5 of the sheet metal 1, and the circular plate portion 4a is brought into close contact with the surface of the sheet metal 1.

As described above, by fitting the engagement convex portion 4b into the engagement hole 5, the fiber molded body 4 is accurately positioned and fixed with respect to the sheet metal 1.

Next, the mold 7 that closes the outer periphery and both end faces of the casting cavity 8, and the cores 9 and 1O necessary for forming the water jacket and connecting bolt holes are set to form the casting cavity 8. The cast-out pins 11 and 12 forming the pair of plug holes 2 and 3 are pushed through the mold 7 and inserted into the casting cavity 8 as shown by the chain lines in FIG. The tip portion is brought into contact with the corresponding fiber molded body 4. Here, due to the configuration of the plug holes 2 and 3 and the spark plug, the tip of the upper cast-out pin 11 is conical, and the tip of the lower cast-out pin 12 is flat. 12 is connected to a connecting plate 13 outside the mold 7, and the connecting plate 13 is lightly pressed and driven toward the mold 7 by a hydraulic or pneumatic cylinder.

Next, a molten aluminum alloy 14 pressurized to a predetermined pressure of several hundred kg/cJ is poured into the casting cavity 8 formed as described above, and the sheet metal 1 and the fiber molded body 4 are poured into the casting cavity 8.
The molten metal 14 is solidified while maintaining the pressurized state. During the above-mentioned pouring, as the molten metal 14 is filled into the casting cavity 8 as shown in FIGS. 3 and 4, the molten metal 14 is filled around the fiber molded body 4, and the molten metal 14 is As the air flows into the voids inside the fiber molded body 4 from the surroundings, the air in the voids is compressed and flows into the fiber molded body 4.
moves toward the engaging convex portion 4b at the center of the sheet metal 1, passes through the engaging convex portion 4b fitted in the engaging hole 5, flows into the inside of the jitmekuru 1, and connects the sheet metal 1 and the core mold 6. It flows out into the gap between.

In this way, the molten metal 14 permeates the entire fiber molded body 4, forming a fiber-reinforced aluminum alloy in which the cast metal and the alumina fibers are composited. Further, since the surface of the sheet metal 1 that the fiber molded body 4 comes into contact with is formed as a smooth surface without being sharpened, the adhesion between the fiber reinforced aluminum alloy and the sheet metal 1 is also improved. In addition, since the wedge-shaped protrusions 1a formed by sharpening the sheet metal 1 are sufficiently cast into the cast metal, the bond between the cast metal and the sheet metal 1 becomes strong.

Next, after the molten metal has solidified, the rotor housing casting is removed by breaking the mold, and the inner end 2a of the upper plug hole 2 is engaged with the engagement hole 5 as shown in FIGS. 5 and 6. A regular plug hole 2 is formed by cutting to a diameter slightly larger than the mating convex portion 4b, and the inner end 3a of the lower plug hole 3 is cut to approximately the same diameter as the other parts to form a regular plug. Form in hole 3.

As explained above, the engagement hole 5 is formed in the sheet metal l in the portion that will be opened as the regular plug hole 2, 3,
Since the fiber molded body 4 is attached to the sheet metal 1 by engaging the engagement convex portion 4b of the fiber molded body 4 in the engagement hole 5, the engagement hole 5 forms an air vent passage and the fiber molded body 4 is In addition to being able to prevent air from remaining in the molded body 4 and prevent composite defects in the fiber molded body 4,
Since the fiber molded body 4 can be accurately positioned and fixed on the sheet metal 1, the means for positioning and holding the fiber molded body 4 on the sheet metal 1 can be omitted or downsized.

In the above example, short alumina fibers were used as reinforcing fibers for the fiber molded body 4, but in addition to this, silicon nitride whiskers as shown in Table 2 below, and silicon carbide whiskers as shown in Table 3 were used. You can also use whiskers.
(Margins below next summer) Table 2 Table 3 In addition to manufacturing the rotor housing R of the rotary piston engine according to the above example, a plate-like member is placed in the casting cavity and a fiber molded body is attached to the plate-like member. It goes without saying that the present invention can be similarly applied to the manufacture of fiber composite members, which are manufactured by holding these in close contact and casting them into cast metal.

In this case, as the reinforcing fibers, carbon fibers, boron fibers, etc. may be used in addition to the above-mentioned ones.

[Brief explanation of the drawing]

Among the drawings, Figs. 1 to 6 relate to embodiments of the present invention, in which Fig. 1 is a partially cutaway vertical cross-sectional view of the rotor housing, and Fig. 2 shows the core mold, the mold, and the essentials of casting, etc. 3 and 4 are enlarged sectional views of the periphery of the fiber molded body at each stage of casting, FIG. 5 is a sectional view of the main part of the manufactured rotor housing, and FIG. 7 is a view corresponding to FIG. 4 according to the prior art. 1. Sheet metal, 4. Fiber molded body, 4b. Engagement protrusion, 5. Engagement hole, 6. Core mold, 7.
Mold, 8. Casting cavity, 9.10. Core,
14... Molten metal.

Claims (1)

[Claims] (1) A fiber molded body is placed closely in a casting cavity on a plate member that is placed in contact with the inner surface of a mold and is cast, and a molten metal is poured into the casting cavity to form a fiber composite member. When manufacturing the plate member, an engaging hole is opened in a portion of the plate member that the fiber molded body comes into close contact with, and an engaging convex portion is formed in a portion corresponding to the engaging hole of the fiber molded body, and the above-mentioned engagement 1. A method for manufacturing a fiber composite member, which comprises casting a molten metal in a state in which a convex portion is fitted into an engagement hole and a fiber molded body is fixed to a plate member.