JPH0122331B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an inorganic fiber reinforced metal composite material. Recently, it is lightweight, has excellent heat resistance, and has high compressive strength.
Materials with high mechanical strength such as tensile strength are now required as materials for turbine blade aircraft components and the like. As this type of material, an inorganic fiber-reinforced composite material in which a metal such as titanium or nickel is reinforced with inorganic fibers such as carbon fiber, boron fiber, alumina fiber, or silicon carbide fiber has been proposed. Conventionally, this inorganic fiber-reinforced composite material has been obtained by arranging metal powders such as titanium, nickel, etc. together with inorganic fibers in a mold and heating them. However, the inorganic fiber-reinforced metal composite material obtained by this method cannot be obtained because, for example, when silicon carbide is used as the inorganic fiber and nickel is used as the metal, the nickel is converted into nickel carbide and nickel silicon in the sintering process. The disadvantage is that the strength of the product is reduced and it becomes brittle. Furthermore, when carbon fiber is used as the inorganic fiber and titanium is used as the metal, the titanium in the resulting product is carbonized, so the resulting product has the disadvantage of low strength and brittleness, similar to the above-mentioned composite materials. Furthermore, in the case of composites of boron fibers and alumina fibers, reactions occur at the interface between the fibers and the metal, resulting in insufficient composites. The present inventors conducted research to provide a method for manufacturing an inorganic fiber-reinforced metal composite material that eliminates such drawbacks, and found that inorganic fibers selected from boron fibers, alumina fibers, or silicon carbide fibers, titanium, and nickel. If an aluminum layer of a limited thickness is interposed between the aluminum layer and the alloy mainly composed of these, the time for the metal to be composited to react with the inorganic fibers will be drastically reduced, resulting in the formation of carbides or silicides of the composite metal. The present invention was completed based on the knowledge that an inorganic fiber-metal composite material obtained without the formation of such substances is highly strengthened. The gist of the present invention is to form an aluminum film with a thickness of 0.5 to 10 μm on the surface of inorganic fibers selected from boron fibers, alumina fibers, or silicon carbide fibers, and to combine the inorganic fibers with powdered or foil-like titanium, nickel, and these materials. An inorganic fiber-reinforced metal composite material is produced by arranging the alloys mainly consisting of Alumina fibers and silicon carbide fibers having a fiber diameter of about 5 to 140 μm are preferably used. Titanium, nickel, and alloys based on these are effective as composite metals. A film of aluminum can be formed on inorganic fibers by an ion plating method (vapor deposition method), an impregnation method, or a dipping method. The impregnation method is a method in which inorganic fibers are immersed in molten aluminum and pressurized; in this case, the temperature of the molten metal is
The standard temperature is 700-750℃ and the pressure is 50-100Kg/ ^cm2 .
When a thin film of low melting point metal is formed on the surface of inorganic fibers under reduced pressure in molten metal, the temperature of the molten metal should be 700 to 750℃.
Perform at 1 torr or less. The thickness of the aluminum film is preferably 0.5 to 10μ. Aluminum and fibers do not form carbide to the extent that a film is formed within this range. The thickness is adjusted by the temperature of the molten metal or, in the case of vapor deposition, the amount of vapor deposition. If the thickness is less than 0.5 μm, the metal and the inorganic fibers will react with each other, which is undesirable, and if the thickness is more than 10 μm, the amount of low melting point metal will increase, which will reduce the adhesive effect of the composite metals, which is undesirable. The composite metal is used in the form of foil (thickness: 50-100μ) or powder (particle size: 40μ or less), and the molding conditions are: heating temperature: 800-1000℃, pressure: 100-100℃.
It is preferable that the pressure is 1000Kg/cm ² and the time is 0.5 to 6 hours. According to the present invention, the fibers and the metal to be composited do not react to form carbides or silicides of the metal, and the aluminum film on the surface of the fiber and the metal to be composited are bonded between the metals during the composite. Since compounds (TixAl (1-x), NiyAl (1-y), etc.) are formed, the fiber/metal bond becomes strong. The resulting inorganic fiber-reinforced metal composite material has high mechanical strength. Next, embodiments of the present invention will be described with reference to Examples, but the present invention is not limited thereto. Example 1 A bundle (bundle of 500 single fibers) of silicon carbide fibers (product name: Nicalon, manufactured by Nippon Carbon Co., Ltd.) with a single fiber diameter of 10 μm was immersed in aluminum melted at 720°C in an autoclave, and the resulting product was 70 kg. A silicon carbide fiber bundle was obtained by applying a pressure of /cm ² to form an aluminum film with an average thickness of 8 μm on the surface of the single fibers. This is placed on titanium foil (thickness 50μ) with a fiber volume ratio of approximately
Arrange them so that they are 30%, stack them in 10 layers, fill them in a mold, and heat them at 850℃ and 800℃.
Kg/cm ² and molded for 1 hour. Table 1 shows the properties of the composite material obtained. Example 2 Silicon carbide fiber bundles coated with the same aluminum film as used in Example 1 were arranged on a nickel foil (thickness 50μ) so that the fiber volume ratio was approximately 30%, and then 10 layers were stacked. The mixture was filled into a mold and molded at 850° C. and 800 kg/cm ² for 1 hour. Table 1 shows the properties of the composite material obtained. Comparative Examples 1-2 Silicon carbide fiber bundles used in Example 1 that do not form any aluminum film, and average thickness in the autoclave used in Example 1
Each of the aluminum films on which a 12 μm thick aluminum film was formed was arranged on a titanium foil (thickness: 50 μm) so that the fiber volume ratio was approximately 30%, and then laminated and molded using the method of Example 1. The results are shown in Table 1. show. Comparative Examples 3-4 The same silicon carbide fiber bundles as those used in Comparative Examples 1-2 were arranged on a nickel foil (thickness 50μ) so that the fiber volume percentage was about 30%, and the same method as in Example 2 was used. The results of lamination and molding are shown in Table 1.

【table】

[Table] Examples 3 to 6 Aluminum coatings of various thicknesses were applied to each of the fibers shown in Table 2 under the conditions shown in Table 2. These fibers were laminated with Ti powder (40 μm or less) and Ni powder (40 μm or less) to obtain a composite material with the characteristics shown in Table 2.

[Table] Examples 7 to 8 Silicon carbide fiber bundles coated with the same aluminum film as used in Example 1 were treated with Ti-6Al.
-4V titanium alloy foil (thickness 100μ) and Ni-Cr alloy (Inconel x -550) foil (thickness 100μ) are each lined up so that the fiber volume percentage is approximately 35%, and 10 layers each are laminated to form 850. C. and 1000 Kg/cm ² for 1 hour to obtain a titanium alloy composite material and a nickel alloy composite material. Its tensile strength is titanium alloy composite material 150Kg/mm ² ,
The nickel alloy composite material was 155Kg/ ^mm2 .

Claims (1)

[Claims] 1. Inorganic fibers selected from boron fibers, alumina fibers, or silicon carbide fibers with an aluminum coating of 0.5 to 10μ thick on the surface.
An inorganic fiber-reinforced metal characterized by arranging titanium, nickel, or an alloy mainly composed of these in a foil shape of 50 to 100 μm or in powder form with a particle size of 40 μm or less in a mold, and then heat-forming it under pressure. Method of manufacturing composite materials.