JPS61250131A - Manufacture of composite member - Google Patents

Abstract

PURPOSE:To obtain a composite member having characteristics such as light weight and high density, by compacting a fiber compact made of plural layers having different fiber densities, arranging the compact so that high density layer is positioned at surface side of product and pouring a cast-in material. CONSTITUTION:Fiber layers A, B, C in which fiber density is increased in order are compacted, and sintered to prepare the fiber compact 3 made of plural layers. The sintered compact 3 is arranged so that the third layer C is brought to contact with the surface of a cavity 4a, and the first layer A is positioned inside the cavity 4a. The cast-in material 5 such as molten Al alloy is poured into the cavity 4a and these are pressed. Poured molten metal is impregnated into the compact 3 to fill the material 5 into pores therein, and the composite member 6 having a prescribed shape is obtd. In the member 6, the surface part where the layer C is positioned is reinforced. The compact 3 is cast-in with high joining strength.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a composite member in which a fiber molded body is cast.

(Prior art) Traditionally, a composite member has been provided by partially casting a fiber molded body into a metal base material, and the properties of the fiber molded body have been utilized to partially improve wear resistance, mechanical strength, etc. The technology used is known.

However, since conventionally a single-density [f molded body is cast], when a fiber molded body with a high fiber density is cast, there is a problem that the bonding strength between the fiber molded body and the cast material is insufficient. have

In other words, in order to obtain sufficient mechanical and physical properties, it is necessary to increase the amount of fiber inserts in the casting to increase the IIM density, but a fiber molded product with a high fiber density has no pores. Due to its small size, it is difficult for the casting material to penetrate inside during casting, and when the casting material comes into contact with the fibers, its temperature decreases and fluidity decreases, resulting in insufficient pressure and filling. There are few knots, and the joint strength between the two is insufficient, which may cause the wA fiber molded body to fall off. If the fiber molded body is made larger than necessary to increase the bonding surface area and thereby improve the bondability, the amount of 11aN used will increase as well as fillability problems, increasing manufacturing costs. It is something to do.

(Object of the Invention) In view of the above-mentioned circumstances, an object of the present invention is to provide a method for manufacturing a composite member that achieves high bonding strength even when a fiber molded product with a high van density is cast. .

(Structure of the Invention) The manufacturing method of the present invention involves laminating and integrating a plurality of fiber layers with different 1iA fiber densities to form a fiber molded body, and then placing 1118 layers of the high fiber density of the m miscellaneous molded body on the mold side. and filling the pores of the fiber molded body with casting material,
This method is characterized in that the fiber molded body is cast in a casting material.

The above-mentioned fiber molded article uses metal fibers such as stainless steel fibers and cast iron fibers, or ceramic fibers, etc., and pressure-forms the fibers to predetermined multiple levels of fiber density, for example, while changing the pressure-molding pressure. , which is made by laminating and integrating fiber layers molded with varying densities. The plurality of m-fiber layers having different lIgN densities are either molded separately or integrally molded at the same time. In particular, when the fiber density is low, mN and a binder may be mixed and pressed during molding to obtain a uniform density product. The binder is made of industrial salt or synthetic resin, and is removed after molding by dissolving it with water or a solvent or by heating it to eliminate it.

Fiber layers with different l fiber densities are laminated and integrated in the order of fiber M density, so that the fibers on both sides are intertwined at the boundary portion of 118111 with different densities. In the case of simultaneous integral molding, this lamination and integration is carried out as it is or in the case of metal fibers, it is heated and sintered to maintain its shape.On the other hand, when molded separately, it is either integrated by applying pressure, or In the case of metal fibers, sintering is performed by heating.

The laminated and integrated fiber molded article is arranged so that the part with high fiber N density is in contact with the mold surface side, that is, the fiber molded product is placed in the mold so that the part with high fiber density is located on the surface side of the product. After placing the aluminum alloy into this mold,
A composite member is manufactured by injecting a casting material such as cast iron in a molten state, filling the pores of a fiber molded body with the casting material, and then surrounding the fiber molded body with the casting material.

(Effects of the Invention) According to the present invention, a fiber molded body having a plurality of fiber layers having different fiber densities is formed, and the fiber molded body is formed so that a portion with a high II density is located on the surface side of the product. By arranging it and manufacturing a composite member by casting it with casting material, the part with high l1lfI density fully exhibits the characteristics of 11 miscellaneous, improving wear resistance, mechanical strength, etc. The portions with low fiber density facilitate the filling of the casting material inside the fibers, and the bonding properties of the portions with high fiber density can be improved to prevent peeling and falling off. In other words, compared to the direct bonding strength between the fiber molded body with high fiber density and the casting material, the bonding strength between the high and low mm density parts is greater because the fibers of both have bonding properties. Become,
Moreover, the casting material sufficiently flows and fills the pores inside the fiber molded body from the parts with low miscellaneous density. It is possible to obtain sufficient bonding properties. As a result, a composite member having features such as light weight, high strength, high elastic modulus, and excellent heat resistance can be manufactured with high productivity even if it has a complex shape.

(Example) Each embodiment of the present invention will be described below.

Example 1 In this example, short fibers (diameter 100μ×211!1) made of steel (845G) were used as all materials, and first,
As shown in Fig. 1, this fiber is put into a press mold 1,
Im* layer A1 second fiber WJ with increasing IN density in order
B and the third fiber layer C are each pressure-molded by changing the compressive load applied by a punch 2°2.

The 1111th layer A has a press forming load of approximately 30 kMc12
A molded body with a porosity of about 0.50/Cry3 (porosity 95%) was obtained. For the second fiber layer B, the press molding load was set to about 100 Ω/cm2 to obtain a molded product with a bulk density of about 1.6 to 1°7Q/cm3 (porosity 80%). M31iAHmC has a press forming load of approximately 30
00 kg/cm2, the bulk density is approximately 5.5
A molded body of g/c++3 (porosity 30%) was obtained.

Next, the first, second and third fibers JIA, B.

C are stacked one on top of the other in order and charged into press mold 1, and punch 2.
2, the fiber layers are laminated and integrated by applying pressure with a press load of about 10 kg/am2, and as shown in FIG.
A fiber molded body 3 consisting of a plurality of fiber layers of a high-density third fiber layer C was obtained. This fiber molded body 3 is heated and sintered to bond each fiber to each other and maintain its shape.

As shown in FIG. 3, the fiber molded body 3 formed as described above is placed in such a manner that the high-density 311tNWI G is in contact with the surface of the cavity 4a in the mold 4, and the low-density 111M layer A side is on the inside of the cavity 4a. A casting material 5 made of molten aluminum alloy is injected into the cavity 4a using a hot forging method. The pressing force at this time was 1000kg1012. The injected molten metal is the first
The tlAH penetrates into the fiber molded body 3 from the fiber layer A side, and the above-mentioned tlAH
A composite member 6 having a predetermined shape is obtained by filling the pores of the molded body 3 with a casting material 5 and casting the fiber molded body 3 at a predetermined position of the tying material 5.

In this composite member 6, the part where the fiber molded body 3 is cast is reinforced, especially the surface part where the high-density fiber layer C is located, and the mechanical strength and physical properties are improved, and the wear resistance etc. are improved. At the same time, this IIIrM molded body 3 is molded with high bonding strength.

Example 2 This example is based on integral molding. First, as shown in FIG.
After adding the low-density material A' mixed with industrial salt (40wt%), the fibers were mixed with the binder at a high density (111180w).
t%, industrial salt 20wt%) is added in a layer, and then punched with a punch 2.2 at a density of, for example, 3 ton/
Compression molding is performed at a pressure of c+a2. The binder is solidified by this compression molding, and the low-density fiber layer 7a having different fiber densities is
and a high-density fiber layer 7b in a layered manner, and the fibers on both sides are joined so as to intertwine at the joining portion of each layer to form an integrally molded fiber body 7.

Next, the binder of the fiber molded body 7 is eluted and removed by heating to 800°C, and then the fibers are sintered by heating to 1200°C, for example, so that a plurality of layers with different fiber densities are laminated together. A fiber molded article 7 was obtained. Similar to the previous example, this IJAN molded body 7 is placed in the mold 4 so that the high-density fiber layer 7b is in contact with the surface of the cavity 4a of the mold 4, as shown in FIG.
A composite member 8 is obtained by injecting the molten metal of the casting material 5 at a weight of 000 kg (1012 kg) to fill the pores of the fiber molded body 7 with the casting material 7, and by casting the fiber molded body 7 with the casting material 5. be.

The binder mentioned above can also be a synthetic resin, which is applied or mixed to the fibers at a predetermined ratio and then pressure molded. After molding, the binder must be eluted with an organic solvent or heated to burn it out. It is removed by Furthermore, when forming a layer with particularly high fiber density, only the fibers may be added and compression molded without mixing a binder.

In the above example, a mixture of fibers and binder with multiple densities is molded together, but the fibers and binder are molded separately, the binder is removed, and then the fibers and binder are pressed together in a stacked state. If necessary, they may be sintered and laminated into one piece. However, when the fiber is integrally molded as described above, the bondability between the IIM and the fiber at the boundary portion is better.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing how each fiber layer is formed by a press mold in the manufacturing method of the first embodiment of the present invention, FIG. 2 is a perspective view showing the laminated state of a tiAN molded body,
The figure is a cross-sectional view showing the state of casting by the mold in the first embodiment, FIG. 4 is a cross-sectional view showing the state of molding of each fiber layer by the press die in the manufacturing method of the second embodiment, and FIG. FIG. 2 is a cross-sectional view showing a state of casting by a mold in Example 2. 1... Press mold 3... Fiber molded bodies A, B, C... Fiber layer 4...
・Mold 5...Casting material 5.8...
...Composite member 7...m Miscellaneous molded body 7a
, 7b... Fiber layer Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 H1 7ε □− Yu↓

Claims (3)

[Claims] (1) A fiber molded body is formed by laminating and integrating a plurality of fiber layers with different fiber densities, and then the fiber layer with a high fiber density of the fiber molded body is placed on the mold surface side to form pores in the fiber molded body. 1. A method for producing a composite member, which comprises filling a molded fiber body with a casting material and casting the fiber molded body with a casting material. (2) The method for manufacturing a composite member according to claim 1, wherein the lamination and integration of the plurality of fiber layers is performed by pressure molding. (3) The method for manufacturing a composite member according to claim 1, wherein the lamination and integration of the plurality of fiber layers is performed by pressure forming and then sintering and joining.