JPS59173269A - Composite metal body - Google Patents

Abstract

PURPOSE:To obtain the composite metal body endurable in high-temp. use over a long period, by coating a core metal comprising Mo with Al. CONSTITUTION:A core material 5 comprising Mo is coated with Al 6, and the surface of Al 6 is further anodically oxidized at need to form an Alumite layer 7. This composite metal body is suitable for a composite material endurable in high-temp. use over a long period as compared with Cu, Fe, etc., and its wide use as a space material such as a super heat resistant sensor or a missle is expected.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a composite metal body having an aluminum coating, and further to a composite metal body C2 in which the coated aluminum is provided with an anodized film.

BACKGROUND OF THE INVENTION Conventionally, an alumite electric wire having two aluminum anodized coatings has been known as a heat-resistant electrical carrier.

Among these alumite electric wires, those made only of aluminum as a conductor have the disadvantage that when used for a long period of time at high temperatures of 400° C. or higher, the aluminum buckles and softens, and loses its function as a conductor.

In order to improve this problem, a composite metal insulator was considered in which the aluminum 2 surrounding the copper 1 used as a conductor was overturned and the surface of the copper 7 was anodized to make it anodized, as shown in Figure IC2. When used for a long time at high temperatures, the aluminum-copper alloy layer 4 rapidly develops and becomes brittle, as shown in Figure 2.
In addition, the electrical resistivity rises rapidly, so that it no longer functions as a heavy insulating wire, and as shown in Figure 3, the aluminum substrate disappears.
In addition, the stock ends increase and the alumite layer partially peels off. To prevent this, there are techniques such as interposing a thin lead film with low heat diffusion between the aluminum and copper boundaries, but this does not provide a fundamental solution.

Since iron diffuses into aluminum and forms an alloy, it is possible to use a combination of aluminum and iron as a conductor, but the electrical resistance increases rapidly at high temperatures, making it impossible to transmit a certain amount of electricity.

The inventors of the present invention found that the alloy f * beggars C due to aluminum and thermal diffusion at high temperatures due to such lumps, and as a result of intensive research on metals that have a small increase in electrical resistance even at high temperatures, they found that molybdenum is optimal. It was confirmed.

Table 1 shows the high-temperature vibration frequency DO2/ρ for each combination of aluminum, copper, iron, and molybdenum, and for comparing the diffusion coefficients of copper and lead.

Table 1 From Table 1, it can be seen that molybdenum has the lowest vibration frequency and the lowest thermal diffusion coefficient relative to aluminum.

Furthermore, as shown in Table 2C, the electrical resistivity of molybdenum at high temperatures does not rise as rapidly as compared to iron and the like.

From the results below, a metal composite coated with a molybdenum core and aluminium has a resistivity that is approximately half that of iron (molybdenum is three times that of copper), and an elastic modulus that is approximately 60% higher than that of iron. Due to its physical properties, such as a linear expansion coefficient of about 1/3 of copper and about 1/3 that of iron, and because it does not react with dilute sulfuric acid, hydrochloric acid, hydrofluoric acid, etc., it is used as a conductive material or as a special corrosion-resistant material. Furthermore, it is expected to be a new material that has characteristics not found in conventional aluminum clad copper materials and aluminum clad steel materials as a special temperature control material.

Table 2 (S1-) shows a composite metal made by crushing a core metal made of molybdenum with aluminum and anodizing the surface or all of the M4 plate, as in the second invention of the present invention. The body is made of heat-resistant electrical insulating material (Nimonarizuru).

This will be explained below with the help of diagrams.
It has a structure in which the surface layer of C Nialuminum is further anodized to form anodized Aluminum (Itl#7).

FIG. 5 shows a state in which the aluminum coating was anodized up to just before the molybdenum core material, resulting in an aluminium content of 1%.

If aluminum coating Ii'4, whose core material is copper or iron, is anodized in an industrial electrolytic bath such as sulfuric acid, the core metal will become accustomed to the electrolyte and cause an anodic reaction, leading to anodic dissolution. Since phenomena such as complete generation of hydrogen gas occur, core materials made of copper, iron, etc. cannot be bonded to alumite.

On the other hand, in the present invention, since the core material is molybdenum, such a phenomenon is less likely to occur, and a strong bond between the core material metal and aluminum or alumite can be obtained.

In the present invention, anodic oxidation of aluminum does not produce an anodic oxide film like that of molybdenum C dialuminum, but molybdenum sulfide and sulfide are densely produced at the interface with aluminum. However, the anodizing treatment of aluminum cannot be fully controlled due to subtle variations in the aluminum coating thickness and uneven thickness, and molybdenum (for example, internal conduction) t: Even if the electrolytic reaction progresses, the aluminum and The mechanical, chemical, and even electrochemical bonding state with molybdenum will not be broken.

Therefore, unlike copper or iron, the metal composite according to the present invention is not only suitable as a composite material that can withstand long-term high-temperature use, but is also expected to have a wide range of applications as space-related materials such as heat-resistant walls and missiles. .

In the present invention, the molybdenum core material (Nialuminum) may be coated by any method such as hot-dip aluminum plating, powder compression molding, aluminum plate roll molding, aluminum electroplating, dry vapor deposition, or aluminum thermal spraying. Although its workability and flexibility are not the same as those of copper or iron,
The metal composite of the present invention can be processed in a wide range of ways, from ultra-fine wires to mold materials.

[Brief explanation of the drawing]

Figure 1 shows the state of a composite alumite wire with a copper core material before high-temperature use71! 2 is a cross-sectional view showing the state after long-term use at high temperatures, FIG. 3 is a cross-sectional view showing the state after progressing from the state in FIG. 2, and No. 5 is the present invention. FIG. 2 is a cross-sectional view of a composite alumite wire showing one example of FIG. DESCRIPTION OF SYMBOLS 1... Copper conductor, 2... Aluminum, 3... Alumite layer, 4... Metal fine, 5... Core material (molybdenum), 6... Aluminum, 7... Alumite bucket.

Claims (1)

[Claims] 1. A composite metal body in which a core metal made of molybdenum is coated with aluminum. 2. A composite metal body in which a core metal made of molybdenum is coated with aluminum, and the surface or the entire surface of the coating is anodized.