JPS6013966B2 - Manufacturing method of boron structural material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a shelf base material, which aims to improve the film quality and mechanical properties of the shelf base material constituting the shelf base material, and to improve the production yield. The object of the present invention is to provide a material suitable for a cartridge cantilever having particularly excellent acoustic properties.

Shelf elements have a hardness second only to that of diamond, and their wear resistance is extremely high, making them useful materials for cutting tools, slider core parts, bearings, etc. /density) is the highest among currently known substances.

This property means that the propagation velocity of sound waves is the highest among existing materials, making it useful as an acoustic material, particularly as a cantilever for cartridges. For example, metals such as aluminum alloys and titanium alloys are used as cantilevers for cartridges, but the specific elastic modulus of both of them is smaller than that of shelf elements, and their frequency characteristics are lower than the Takagi resonance frequency ( In the range of 1 female HZ to 40 kHz (normally 1 female HZ to 40 kHz) or less, the response tends to decrease, a so-called middle sag phenomenon, tends to occur, and it has the disadvantage that it is difficult to obtain a flat frequency characteristic.

Furthermore, there is a drawback that good transient characteristics, which affect the followability of the pickup cartridge, cannot be obtained. In order to overcome the drawbacks of these known materials, a cantilever for cartridges using shelf elements has appeared. Among them, the cantilever for cartridges with tapered pipes is said to greatly contribute to flattening the frequency characteristics in the high range of 4 HZ or more, compared to the cantilever for cartridges with flat pipes, and its appearance is eagerly awaited. It is difficult to obtain products using shelving elements in a delicate structure by methods such as casting or rolling, and for this reason, in most cases, when producing products using shelving elements, materials other than shelving elements are used. It is used as a composite in which a shelving film is formed on a substrate made of a material by vapor deposition, sputtering, CVD, or the like. Among the above-mentioned conventional methods for forming a shelving film, the CVD method is considered to be able to obtain the highest quality film.

However, in the case of the CVD method, since the deposited film is deposited extremely faithfully on the supporting substrate, the inherent strain or mechanical properties vary greatly depending on the surface roughness and shape of the supporting substrate. Furthermore, in general, when a substrate is removed by an appropriate method, most of the substrates are destroyed or have poor mechanical properties even if their shape is preserved during the removal process.

The present inventor solved the problems of these conventional examples by forming the base body into a tapered shape that shares a common vertex, and at the same time polishing the surface to a certain roughness.

By the method of the present invention, it is possible to provide a shelf element tapered vipe structural material that exhibits excellent mechanical properties and has a good appearance without causing destruction of the shelf element structural material as in the past. The method of the present invention will be specifically explained below. First, as shown in Fig. 1, a pair of rolling molds 1 are vertically symmetrical and have a shape capable of forming a tapered shape sharing a common vertex.
A wire rod 3 made of tantalum, niobium, titanium, tungsten, molybdenum, or nickel is sandwiched between the wires 2 and 2, and an appropriate amount of abrasive having a particle size of 1 to 10 mm is added thereto. In this case, it is desirable to add the abrasive after mixing and dispersing it in a suitable liquid. Thereafter, by applying a constant load and sliding the wire back and forth in a direction perpendicular to the wire, the base body 4 is rolled into a tapered shape sharing a vertex of a constant size as shown in FIG. In this case, the appropriate values for the load and sliding speed will vary depending on the hardness and tensile modulus of the twill material, the diameter of the bran, etc. Next, using this as a support base, a shelf element is formed by CVD method. Infrared heating, resistance heating, high frequency heating, etc. are used to form shelf elements on a supporting base that has a tapered shape that shares the apex formed by the above method and has a certain surface roughness. By external heating, the support substrate is uniformly heated and generates heat, and shelf elements are precipitated by a reductive decomposition reaction as shown in the following equation. Wave X3 (10) Spot 21 is (10) Bait X (However,
is a halogen element such as CI, orbital, 1, etc.) In addition to BX3, there are hydrides and the like as raw material gases used in the CVD method.

Next, a sample having a tapered shelf-like broken membrane that shares apex, which was deposited on the surface of a supporting substrate by CVD in a reaction chamber as described above, is taken out from the reaction chamber and cut into desired lengths from the shared apex. Thereafter, the base is removed to produce a tapered pipe structural material made of only shelf elements.

According to the present invention, it is possible to obtain a tapered pipe structural material consisting of only shelf elements, which has excellent appearance and excellent mechanical properties.

In the present invention, the reason why the polishing and rolling method is used in forming a base having a tapered shape that shares a common vertex is that the roughness of the formed surface can be made uniform to a constant surface grain size. Other methods have also been tried, but the chemical electric field etching method has the disadvantage that the reproducibility of the shape is extremely poor, and the unevenness of the formed surface is uneven and large. Further, the knock-out method is also not preferred for almost the same reason. Further, in the present invention, the method for precipitating shelf elements is limited to the CVD method because the vacuum deposition method has a slow deposition rate and is problematic in terms of cost.

Further, the above manufacturing method is effective regardless of whether it is a CVD method under reduced pressure or a CVD method under normal pressure. Incidentally, in order to obtain the tapered pipe structural material itself consisting of the manufactured shelf element alone, it was necessary to remove the base, and for this purpose, the Ibological method was used.

Examples of the present invention will be described below in comparison with conventional methods.

Tantalum wire and tungsten wire were prepared as the base wire materials, and abrasives with particle sizes of 1〆, 5R, and 10〃 mixed and dispersed in oil at a weight ratio of 1:1 were prepared. Each combination was inserted into a rolling mold, and a load of 5k9 was applied to form a tapered base with a maximum diameter of 250mm, a maximum diameter of 4mm, a diameter of 150mm, and a taper on the length 5 side, sharing the vertex. Various types were formed.

The substrate thus produced is as follows. Rolled from 1-Shio inttal wire using an abrasive with a grain size of 1mm,
■Those rolled from tantalum wire using an abrasive with a grain size of 5, those rolled from '3 Shio tantalum wire using an abrasive with a grain size of 10, and those rolled from '41 tungsten wire with a grain size of 1 Buddha. Rolled using an abrasive, [5 tungsten wire rolled using a 5r grain abrasive, '61 tungsten wire rolled using a 10 grain abrasive, '
7' niobium wire rolled using an abrasive with a grain size of 5mm, '81 titanium wire rolled with a 5mm grain abrasive, and '91 molybdenum wire rolled with a grain size of 5mm. 00 nickel wire to particle size 5
(11) Rolled tantalum wire without using an abrasive; (12) Rolled tungsten wire without using an abrasive; (13) Tantalum. (14) A tapered shape that does not share a vertex from the line using an abrasive with a grain size of 5. (14) A chemical etching method made from tantalum, (15)
One made using the tapping method from loose tantalum
A support substrate consisting of 9 fleas was used.

Each of these was placed in a reaction chamber and
3) and hydrogen (2) and hydrogen (25) for the former.
at a rate of 0'/min, and for the latter at a rate of 1000/min.
was supplied at a rate of /min. Then, the supporting substrate was heated to 115 mm by infrared heating and held for 6 days, and 20 pieces of shelf elements were precipitated on the surface of the supporting substrate. After that, it was taken out from the reaction camellia and the length was 5 mm from the shared vertex. After cutting into the sail, the substrate was removed. Each of the materials obtained as described above was supported at both ends of the 4-strand span, and a load was applied to the center at one point, and the mechanical strength was evaluated based on the load at which a crack occurred.

The number of samples was 2 sheets each, and the average value is shown in the table below. The table below also shows the yield when removing the base and obtaining the shelf element tapered pipe structural material. *1) Sample modifications marked with a circle are those according to the present invention, and the others are conventional methods.

*2) All samples other than Sample No. 13 are samples that have a tapered shape that shares a common vertex.

As is clear from the results in the table above, it can be seen that according to the method of the present invention, the mechanical strength and the yield of the shelf element tapered pipe structural material are significantly superior compared to the conventional method.

In addition, the shelf element tapered pipe structural material according to the present invention was processed into a cantilever for a cartridge, and its characteristics were evaluated. As a result, as shown in Figure 3, the so-called sagging phenomenon in the frequency characteristics, which has been considered a drawback with conventionally known materials such as aluminum alloys and titanium alloys, as well as flatness at high frequencies of 4 HZ or higher, and tracking. The transient characteristics, which affect performance, were significantly improved. Moreover, the shelving film with high elastic modulus without strain or microcracks can be used in a wide range of applications as mechanical parts.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing the method of manufacturing the supporting base according to the present invention, Fig. 2 is a side view showing the same supporting base, and Fig. 3 is the frequency when the tapered pipe structural material according to the present invention is used as a cartridge. FIG. 3 is a diagram illustrating characteristics in comparison with a subordinate material. 1, 2...Mold, 3...Wire rod, 4...Support base. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1. A cylindrical wire rod is inserted into a pair of vertically symmetrical molds, an abrasive of a certain particle size is added thereto, and then a certain load is applied to the wire rod perpendicularly to the wire rod. A tapered base having a common apex of a certain size is rolled by sliding it back and forth in the direction, and then the rolled base is used as a support base, the base is heated, and a chemical is applied onto the base. A method for producing a boron structural material, characterized in that boron is formed by a vapor deposition method (CVD method). 2. The method for producing a boron structural material according to claim 1, wherein the supporting base is made of a metal selected from the group consisting of tantalum, niobium, titanium, tungsten, molybdenum, and nickel. 3. The method for producing a boron structural material according to claim 1, wherein the abrasive has a particle size of 1 to 10 μm.