JPS60251247A - Metal reinforced by inorganic fiber and its manufacture - Google Patents

Abstract

PURPOSE:To manufacture a metallic composite material reinforced by heat resisting nonmetallic inorganic fibers by containing the inorganic fibers to which a coating film of a suitable compsn. composed of B and Si is deposited from gaseous phase into alloy, etc. composed mainly thereof. CONSTITUTION:The coating film composed of >=5mol% B and <=95mol% Si is deposited or the inorganic fiber such as carbon fiber from gaseous phase by chemical vapor depositing method. Next, the fiber is dipped in molten metal of Al, Mg or alloy, etc. composed mainly thereof, or said molten metal is impregnated to said fiber, and the metallic composite material reinforced by nonmetallic inorganic fiber having >=800 deg.C heat resistance is obtained. Said metallic composite material can be made as the material superior in specific strength, specific elasticity and heat resistance by containing the inorganic fiber coated with the film composed of B and Si which are wettable easily with said molten metals.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a composite material of aluminum-based and magnesium-based metals containing inorganic fibers.

Inorganic fiber-reinforced composite materials with high specific strength and specific modulus, such as carbon fiber-reinforced plastics, are widely used in aerospace flying objects, medical equipment, land and sea transportation equipment, sports equipment, etc. Although it can also be used, it has the disadvantage of poor heat resistance due to limitations on the thermal properties of the base material plastic. Therefore, there is a strong need to improve this point and develop composite materials with high specific strength, specific modulus, and heat resistance, and research into fiber-reinforced composite materials using aluminum, magnesium, or their alloys as base materials is in progress. It is progressing.

(3) Since inorganic fibers generally have high brittleness, in order to arrange or disperse them in the metal matrix without impairing their mechanical properties, it is necessary to soak the fibers in molten metal or to A method of impregnation with molten metal is preferred. However, this method requires that the fibers be wetted with molten metal;
In many cases, inorganic fibers are difficult to wet with molten aluminum or magnesium metal, and this is a drawback in the production of inorganic fiber-reinforced metals.

In order to overcome this gap and make the fibers more easily wetted by the molten metal, it is desirable to coat the fibers with a film of a substance that is easily wetted by the molten metal. As such a coating, titanium
A known method using an interboron compound (Japanese Patent Application Laid-Open No. 51-81
703), but the present invention differs from this in that inorganic fibers are coated with either a boron-silicon compound or elemental boron, and this is mixed into molten metal. The present invention provides a method for incorporating fibers coated with a metal, which is superior to the known titanium-boron coating (4) in terms of making it easier to wet with magnesium, magnesium, or alloys thereof, and a composite material thereof.

Elemental boron and boron-silicon intercompounds described in the present invention are those which compositionally contain 5 mol% or more of boron and 95 mol% or less of silicon. Here, the boron-silicon compound includes compounds such as B', 2Si, B6it, B4Si, etc., but does not necessarily mean only these stoichiometric compounds. It simply means that the composition contains both elements.

The stoichiometric compounds range from 75 to 97 mole percent boron and from 5 to 25 mole percent silicon.

As an inorganic fiber, in an inert atmosphere, 800℃
Heat-resistant nonmetallic fibers having a melting temperature, softening temperature, or sublimation temperature above the above are used.

Examples include carbon, silicon carbide, alumina, zirconia, silica, titania, titania-silica, alumina-silica, boron nitride, silicon nitride, and alumina-boria-silica fibers. Carbon (5) Elementary fibers include those in the carbonization stage and graphitization stage, and include polyacrylonitrile type, rayon type, pitch type, liquid crystal pitch type, and others classified by raw material fiber.

Moreover, metal carbide fibers other than silicon carbide can also be used. The names of the above inorganic fibers indicate the main components, and even fibers with the same name may have different manufacturing methods, and the surface characteristics may vary accordingly. However, the method of the present invention This does not impede the application of the For example, silicon carbide fibers made from polycarbosilane contain silica and some elemental carbon in their composition.

Further, fibers whose surfaces are coated with various components of the above-mentioned fibers or mixtures thereof on inorganic fibers are also included in the starting material fibers of the present invention. Examples include carbon fibers whose outer surfaces are coated with silicon carbide or boron nitride, and polycarbosilane-based silicon carbide fibers. There are several different types of alumina fibers, including those that contain 20% by weight or less of silica and are generally called alumina fibers (6). Alumina-silica fibers have various composition ratios.

These fibers include long fibers with a single fiber or filament diameter of 5 to 30 μm in most cases, as well as short fibers. Some short fibers have a diameter of around 3 μm depending on the manufacturing method. The average length is around 501 m1, and there are also shorter and longer ones. There are also products made by cutting long fibers. In addition, the shape may be yarn, tow, or woven fabric made of multiple filaments of long fibers.
There are paper-like and felt-like types in which filaments are entangled with each other. Short fibers include paper-like, felt-like, cotton-like fibers, and threads.

As described above, in the present invention, fibers of various shapes can be used as raw material fibers, and the shape of the fibers does not limit the present invention.

The thickness of the coating of the boron-silicon compound or elemental boron coated on the fibers is preferably 10 μm to 1 μm. Furthermore, a range of 50 to 500 people is more desirable.

(7) In order to coat the above-mentioned film on the inorganic fiber, a method of depositing from a gas phase is suitable. There are physical vapor deposition methods, chemical vapor deposition methods, and a mixture of both methods, but the chemical vapor deposition method is most suitable. In this method, a halide or hydride of boron or silicon, for example, is used as a raw material for film deposition and is brought into contact with heated inorganic fibers. This method includes a method of reducing boron and silicon halides. For example, a preferred method is to contact the heated fibers with boron trichloride and silicon tetrachloride together with a gas containing zinc vapor. Of course, when coating with a 100% boron film, no silicon compound is included in the gas. An inert gas or a reducing gas can be mixed into the above-mentioned coating gas as a carrier gas or a concentration adjusting gas. When using the zinc vapor reduction method, the coating temperature is 500℃ or higher:
, 900°C or less is desirable. The coating temperature by the reduction method that does not use zinc vapor or the thermal decomposition method is generally 600 (8
) ~1500°C.

In order to mix the inorganic fiber coated with boron or a boron-silicon compound into the base metal, it is desirable to bring it into contact with molten metal.

This can be done by dipping or passing the coated fiber through the molten metal.

In the coated fiber aggregate of the present invention, the interstices of the filaments can be substantially completely filled with metal without special pressure.

As metals, aluminum, magnesium, and alloys containing these as main components are used. For example, in the case of an aluminum alloy, the components contained in the alloy include copper, manganese, silicon, magnesium, and silicon-magnesium. Magnesium alloys include aluminum, zinc, manganese, silicon, copper, and nickel. Since there are many types of contained components, it is difficult to describe their content rates. As the base metal, zinc, lead, tin, or an alloy containing these as main components can also be used. Inorganic fiber-reinforced (9) metals made of these materials can be used for applications that utilize their frictional properties.

The most typical method used to produce the composite material of the present invention is to feed inorganic fiber threads into a coating chamber heated to around 700°C, bring them into contact with a vapor deposition gas, and coat them with a film. The material is then passed through a molten base metal under a reducing or inert atmosphere, after which the base metal is solidified. Since the wire can be obtained by this method,
These can be assembled into composite materials with different shapes by hot pressing.

Examples will be described below to specifically illustrate the present invention.

Example 1 A filament of liquid crystal pitch-based carbon fiber with a diameter of 12 μm, an elastic modulus of 48 x 103 kg/Wn2, and a tensile strength of 260 kg/nwn2. 1000 long fibers were heated at 700°C.
held horizontally in a coating chamber heated to 1:60 BCl3.
A mixed gas of -Ar was flowed, and a mixed gas of zinc vapor and H2 was mixed therein and brought into contact with the fiber (10). A boron coating was applied onto the carbon fibers. The fibers were moved through molten aluminum at 700° C. in a hydrogen atmosphere and drawn out into the atmosphere without being exposed to the atmosphere.

A wire was produced in which the interstices of the filaments were completely filled with aluminum. The fiber volume content was 32% and the tensile strength was 78 kg/mm.

Example 2 PAN-based high-strength type carbon fiber yarn consisting of 3000 filaments with a diameter of 7 μm and having a silicon carbide coating on the outer surface was mixed with a volume ratio of 1:5:60 B C]3.5iC14, Ar
After passing through a coating chamber containing boron and silicon at 700°C flowing with a mixed gas of I pulled it out.

A wire was obtained in which the filament gaps were completely filled with Mg alloy. Cross-sectional area approximately 0.3+nm2, tensile strength 9
It was 4 kg/mm2.

(11) Comparative Example A fiber-solubilized aluminum wire was prepared under the same conditions as in Example 2 using PAN-based high modulus type carbon fiber. Further, a fiber-reinforced aluminum wire was prepared from the same carbon fiber under the same conditions as in the example except that 5iC14 was replaced with TjC]4. In the case of the boron-silicon coating, the metal penetrated into the center of the yarn, but in the case of the titanium-boron coating, it penetrated only about 30% of the outer portion of the yarn.

Example 3 Diameter 137zm, tensile strength 2] Okg/+nm
Polycarbosilane silicon carbide fibers consisting of 500 filaments of No. 2 were mixed with BCl at a volume ratio of 4:1:50.
A mixture of iC1, Ar, zinc vapor, and hydrogen was passed through a coating chamber at 700°C for a residence time of 6 minutes, and then the molten aluminum alloy (containing 13% silicon) was heated at 700°C under a hydrogen atmosphere. It was continuously drawn out into the atmosphere at room temperature. A wire was obtained in which the filament gaps (12) were completely filled with the alloy. Cross-sectional area approximately 0.2n+n+2. Tensile strength 78 kg/nun
"Met.

Example 4 An alumina long fiber yarn containing 15% silica and having a diameter of 17 μm and a tensile strength of 180 kg/own was treated under the same conditions as in Example 2 to impregnate dissolved aluminum. Fiber content: 34 volumes % and a tensile strength of 67 kg/mu2 was obtained.

Patent applicant: Director of the Agency of Industrial Science and Technology Kawa 1) Hirobe Designated agent: Ryozo Hayami (13), Director of the Osaka Institute of Industrial Science and Technology, Agency of Industrial Science and Technology

Claims (10)

[Claims] (1) Heat resistant to 800°C, with a coating on the filament surface consisting of 5 mol% or more of boron and 95 mol% or less of silicon.
Aluminum containing the above non-metallic inorganic fibers,
A composite material of metals selected from magnesium and their alloys. (2) 75-97 mol% boron and 5-25 mol% silicon
The composite material according to claim 1, which is a coating consisting of. (3) The composite material according to claim 1, wherein the inorganic fibers are carbon fibers. (4) The composite material according to claim 1, wherein the inorganic fiber is a fiber containing 80% by weight or more of silicon carbide. (5) The composite material according to claim 1 (1), wherein the inorganic fibers are fibers containing 80% by weight or more of alumina. (6) Inorganic fibers on the outer surface contain silicon, boron, titanium,
The composite material according to claim 1, which is a fiber having a coating of a carbide of a metal selected from the group consisting of zirconium, tungsten, niobium, and tantalum, or a mixture thereof. (7) The composite material according to claim 1, wherein the inorganic fiber is a fiber having a coating containing boron nitride on the outer surface. (8) A coating consisting of 5 mol% or more of boron and 95 mol% or less of silicon is deposited from the gas phase onto inorganic fibers, and this fiber is coated with aluminum, magnesium, or an alloy selected from the group consisting of aluminum, magnesium, and alloys containing these as main components. A method for producing a metal composite material reinforced with non-metallic inorganic fibers having a heat resistance of 800% or more, the method comprising the step of incorporating the fiber into the metal. 9. The method of claim 8, wherein the boron is deposited from boron trichloride and the silicon is deposited from silicon tetrachloride. (10) A patent characterized in that it includes a step of impregnating the gap between the filaments of the fibers covered with a coating consisting of 5 mol% or more of boron and (2) 95 mol% or less of silicon using a metal melt. The method according to claim 8.