JPS61209032A - Method and apparatus for mixing ultra-fine particles - Google Patents

Abstract

PURPOSE:To obtain a uniform mixture of ultra-fine particles with good efficiency, by respectively forming at least two kinds of ultra-fine particles in separate forming chambers and introducing the same into feed pipes by carrier gas to unite the feed tubes to meet the particle streams. CONSTITUTION:A material A (Ag) and a material B (Fe) are respectively prepared in a first forming chamber and a second forming chamber and, after evacuation, both materials A, B are evaporated under heating to form ultra-fine particles with a particle size of 100Angstrom . The formed ultra-fine particles are respectively introduced into feed pipes 21, 22 by carrier gas H2 and both particle streams are met at a forward area passing a double pipe part 24 in the same flow direction to be discharged to a discharge chamber 3 as an uniformly mixed feed stream. The inner diameter of the feed pipe 21 is 1.6mm and that of the feed pipe 22 is 4.5mm and the differential pressure between the first and second forming chambers is generally set to a range of 30-150 torr to obtain a good confluent mixture. By this method, even from metals or metal compounds capable of not being evaporated in the same evaporation chamber, an extremely uniform powdery mixture can be prepared.

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention is a method for uniformly mixing ultrafine particles of two or more types of metals, nonmetals, compounds, etc., which can be used in fields such as powder metallurgy, ceramics, and magnetic films. The present invention relates to a method and an apparatus thereof.

(Prior Art) Conventionally, two types of materials have been heated and evaporated in one vacuum evaporation chamber, and ultrafine particles thereof are simultaneously evaporated onto the surface of a substrate to produce a mixed evaporation film.

(Problems to be Solved by the Invention) The method for mixing ultrafine particles described above is limited to materials that can be evaporated under the same vacuum conditions, such as AU and Fe; It is difficult to simultaneously deposit a film of mixed ultrafine particles, and even if it is possible to create a film of mixed ultrafine particles such as silver and iron, the production speed is slow and mass production is difficult. It is extremely difficult to manufacture an agglomerate of mixed ultrafine particles, such as an agglomerate with a predetermined structure, which is a structural material manufactured by a sintering method or a melting method using as a raw material. In connection with this, the invention of the present application has previously proposed a method for producing a green compact having a predetermined structure in which two or more types of ultrafine particles are mixed. (Patent Application No. 59-210366)
.

(Problems to be Solved by the Invention) The present invention is suitable for mass production by efficiently mixing two or more types of ultrafine particles using arbitrary materials, and is also suitable for mass production, as proposed in Japanese Patent Application No. 59-210366. As an example of the method for manufacturing the green compact of the invention, we have proposed a method that allows two or more types of ultrafine particles to be mixed much more uniformly than when using an ultrafine particle mixing device that mixes through a mixing chamber. In this proposed method, at least two types of ultrafine particles are transported and introduced into each transport pipe using a carrier gas, these transport pipes are oriented in the same transport direction, overlapped or combined, and the The present invention is characterized in that the transport flows of at least two types of ultrafine particles are made to flow in the same flow direction and are merged to mix the at least two types of ultrafine particles.

Furthermore, the present invention proposes a mixing apparatus for carrying out the above method, which includes at least two ultrafine particle generation chambers, each of which contains a container containing a different amount of material to be evaporated; A heating device to heat the material, a vacuum device to evacuate each chamber, a carrier gas introduction pipe to be introduced into each chamber, and a conveyance pipe led out from each chamber are provided, and each generation Part 1: Overlapping or combining two or more transport pipes leading out from the chamber in the same transport direction.
A conveying pipe in which at least two types of ultrafine particles are mixed is connected to a mixed ultrafine particle discharge chamber, which is provided extending from the tip of the 11th part or the combined part.

Next, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows an example of an apparatus for uniformly mixing ultrafine particles of two types of materials. In the drawing, (1) is the first ultrafine particle generation chamber, (
No indicates the second ultrafine particle generation chamber, (3) indicates the mixed ultrafine particle discharge chamber, the first ultrafine particle generation chamber (1) (hereinafter simply referred to as the first generation chamber (1)), the second ultrafine particle generation chamber (1) (hereinafter simply referred to as the first generation chamber (1)), Fine particle generation chamber (no)
The second generation chamber (hereinafter abbreviated as tsu) and the mixed ultrafine particle discharge chamber (3) (hereinafter abbreviated as discharge chamber (3)) are connected to vacuum pumps (4), (5), and (6) through pipes (7), respectively. (8)
(9) is connected. (10ai+■ is the connecting pipe (
n (8) shows the control valves inserted in (9) respectively.Furthermore, the first generation chamber (1) and the second generation chamber (one end of which is connected to a gas supply source (not shown) such as a gas cylinder, respectively) Introducing carrier gas!' (13 (14) are connected via the control valve a9ae. Furthermore, in the first generation chamber (1), a graphite crucible or the like containing the material A to be heated and evaporated is placed in the lower part of the first generation chamber (1). The second generation chamber (D contains a heat-resistant material such as aluminum oxide containing the material B to be heated and evaporated. Coating W basket container (19 and heating device r11 for directly heating it with electricity)
■Equipped with. ■ is a first conveying pipe which has one end opened above the first generation chamber (1), passes through its first side wall in an airtight manner, and is led out to the outside; A second conveying pipe is shown which has one end opened upward and is airtightly penetrated through the first side thereof and led out.According to the present invention, the first conveying pipe (1) and the second conveying pipe are separated from each other. For example, 2 points in the same direction as shown below.
Connect so that it has a heavy pipe section. That is, the first conveying pipe (2) is made of a narrow tube with an inner diameter of 1.6 ms + closed, and its outlet is airtightly passed through one side wall of the upper part of the second generation chamber (2).
Introduced into the production chamber, the tip (22a) is inserted into the base (22b) of the second conveying pipe (2) having an inner diameter of 4.5 am+.
It is inserted concentrically from the open end of the first conveying pipe (2) and consists of the tip (21a) of the first conveying pipe (21a) and the base (22a) of the second conveying pipe (2) extending parallel to each other in the same direction, and having a concentric It constitutes a double pipe part [phase] in which a cylindrical gap passage (2) is formed. The tip (22a) of the 211th feed pipe (2) is connected to the discharge chamber (
3) is constructed so as to airtightly penetrate the side wall of the upper part 1 and open therein. The introduction tip (22a
) can be provided with a movable substrate (2) as required. Also, when forming a thick film compact on a substrate ■,
If it is desired to make the opening of the tip (22a) smaller, a spray nozzle with a smaller diameter than this is attached to the tip, or the tip is processed to have a smaller diameter.

Next, the operation of the above device will be explained.

Container in the first generation chamber (1) (A as material A in +71
(Prepare J, and prepare Fe as material B in container a9 in second generation chamber (2). Vacuum pumps (4), (5),
H2 is introduced as a carrier gas into the chambers (1) and (2) from the one-way gas inlet pipes a3 and (11D), respectively, which operate the chambers (6), and Ag and e are heated and evaporated by the heating devices The operating conditions are shown in Table 1 below.

Table 1 Thus, the particle size of the evaporation product in the first generation chamber (1) is 100
Ultrafine particles (Al) of 0 Å or less are transported by the gas (2) and introduced into the upper first transport pipe (2) from its base (21b), and the transport flow flows into the second transport pipe from its tip (21a). On the other hand, the Fe ultrafine particles with a particle size of 1000 Å or less produced by evaporation in the second generation chamber (1) were transported by the gas and inserted into the second transport pipe above it. Gap passage around the tip (21a) of the first conveying pipe ■
The Fe transport flow passes through the double pipe part @ and passes through the intermediate part (22c) of the transport pipe (2).
1. The flow is parallel to the transport flow and joins each other at a predetermined flow velocity. In this case, a uniformly mixed transport flow of A(l and Fe) is released into the discharge chamber (3) from the tip of the second transport pipe (2).

The released gas is gradually exhausted by the vacuum pump ae. In this way, ultrafine mixed powder of AQ/Fe is gradually deposited in the discharge chamber (3). In the figure, (3a) shows a shielding plate. Note that the flow rate of the discharge stream is, for example, 14.8. If necessary, a mixed powder compact can be obtained by spraying it onto the substrate (2) provided in front of it.

Furthermore, as is clear from Table 1, the first generation chamber (1) and the second
The differential pressure inside the generation chamber was set at 20 Torr, but it is generally 30 Torr.
A range of 150 Torr to 150 Torr is preferable, whereby good convergence mixing of both conveying streams can be obtained. The thus obtained mixed powder was taken out from the discharge chamber (3) and analyzed by X-ray microanalysis (20kV, 0.03/A, spot size φ3) to examine its Ag-Fe dispersion mixing degree. .

The results are as shown in the second diagram. A uniform dispersity curve of FeAg as shown on the left side of the second diagram was obtained. On the right side, for comparison, the analysis results of a FeAg mixed film made by the dual simultaneous evaporation method are shown.

As is clear from this, no difference was observed between the two, and it was confirmed that AgFe was mixed extremely uniformly in the mixed powder obtained by water spraying.

For comparison, the above-mentioned patent application filed earlier in 1983-2103
A mixed powder of Ag and Fe was produced using the mixing apparatus disclosed in No. 66, and the mixed state was similarly analyzed. The results are shown in FIG. As is clear from comparing FIG. 2 and FIG. 3, water droplets can be mixed in multiple types by providing a mixing chamber in the middle of a conveying pipe extending from each generation chamber, as in the mixing device disclosed in the above-mentioned application. It was confirmed that a significantly more uniform mixture could be obtained compared to the method of mixing ultrafine particles.

FIG. 4 shows an example of an apparatus for uniformly mixing ultrafine particles of metal and ceramics, and the first generation chamber (
1) A W basket container (I9) coated with a heat-resistant coating such as aluminum oxide for heating and evaporating Ni as the evaporation material A and a heating device for directly heating it with electricity is installed in the second generation chamber (2). a container (2b) containing 11 as evaporation material B for heating and evaporation;
and an electron beam type heating device for heating the same, and the configuration shown in FIG. is the same as

This device is operated, for example, under the operating conditions shown in Table 2 below.

Table 2 In this implementation, the evaporated ultrafine Ti particles react with a part of the introduced NH3 in the second generation chamber (2), and the TiN
The TiN becomes ultrafine particles of nitride and is transported by NH3 gas into the second transport pipe.
After communicating the gap passage between the double pipe part [phase] with the first transport pipe (■), each of the They merge at a constant flow rate and are released into the discharge chamber (3) from the tip of the second conveyance pipe (3) as the old/TiN mixed conveyance flow, and Ni/TiN uniformly mixed at a predetermined ratio is discharged into the discharge chamber (3) from the tip of the second conveyance pipe (■). A mixed powder of TiN is obtained.

The results of X-ray analysis of the Ni-TiH mixed powder obtained in this experimental example are shown in FIG. Since the ultrafine mixed powder of Ni and TiN cannot be obtained by the two-component simultaneous vapor deposition method, it is not possible to provide a comparison. FIG. 6 shows the results of X-ray analysis of the Ni-TiN ultrafine particle mixed powder using the mixing device disclosed in the earlier patent application. From the comparison between FIG. 5 and FIG. 6, it can be seen that the use of water droplets allows for a much more uniform mixing of ultrafine Ni-TiN particles.

FIG. 7 shows an example of a mixing apparatus for carrying out a method of mixing three types of ultrafine particles. 1), the second generation chamber (2), the discharge chamber (3), and their attached equipment are approximately the same as those shown in the embodiment shown in FIG.
A third ultrafine particle generation chamber (hereinafter referred to as the third generation chamber) is interposed between the generation chamber (2) and the discharge chamber (3), and a material C to be evaporated, such as Cu, is placed in the lower part of the interior. A container ■ containing the gas and a heating device ■ to heat and evaporate it are provided, and the other end of the gas introduction pipe ■ whose other end is connected to a supply source such as a gas cylinder is connected to the chamber ■ via a control valve ■. . A carrier gas such as ■2 or Ar is introduced from the gas introduction pipe (■), and a third conveyance pipe (2) is provided at the upper part of the chamber (2) to airtightly penetrate the first side wall and lead out. ), airtightly penetrates the opposing side walls of the chamber (2), and inserts the tip (
22a) concentrically and both tubes (33b) (22a
) and an additional double pipe section (2) in which a cylindrical gap passage (2) is formed between the pipe (3) and the tip (3
3a) is introduced through the side wall of the discharge chamber (3) in a gas-tight manner so as to open into the discharge chamber (3). In this embodiment, the inner diameters of the first conveying pipe (2), the second conveying pipe (2), and the third conveying pipe (2) are 1.6 mm and 4.5111 mm, respectively. It was set to 7.7m.

A() using the above device under the operating conditions shown in Table 3 below.

The ultrafine particles produced by evaporation of Fe and Cu are separated into each double tube part■
Through the third conveying pipe (■), the two conveying flows of the first ^0 and Fe are mixed together in the same direction, and the Fe mixed conveying flow and the Cu conveying flow are similarly combined and mixed, and these three types are mixed from the third conveying pipe (■). such that a mixed carrier stream of 100% was obtained in the discharge chamber (3).

The X-ray analysis results of the mixed powder thus obtained are as follows:
As shown in the figure. As is clear from this, it is recognized that the three mixed components are mixed extremely well and uniformly.

As can be seen from the above, according to Mizutoshi, in order to obtain extremely good mixing of two or more types of ultrafine particles, the transport tubes for the different types of ultrafine particles are directed directly in the same direction midway through the transport tubes. This is achieved by merging the flows, and in addition to the above embodiments, the following modifications are also possible. That is, as shown in Figure 9, for example, two first and second
The transport pipes ■■ are combined into a common single-wood transport pipe a'), and the open ends of the two first and second transport pipes QD■ are oriented in the same direction and their mutual angle α is at most 45°. It is preferable not to exceed it.

FIG. 10 shows a modification example in which three types of ultrafine particles are mixed,
In this case, the conveyance section') and the additional third conveyance tube
3').

In addition, instead of the previous embodiment, when mixing three or more types, for example, the first, second, and third conveying pipes @ 11 As shown in the figure, the space passages (3
As shown in Figure 12, these transport pipes f2D@@ may be combined into one common transport pipe (3').
3').

As shown in Figures 13 and 14, the final discharge chamber (3) is provided with at least one thin tube (2) projecting to the outside, and is placed in the atmosphere or on a substrate (3) provided in a vacuum chamber (2). The powder may be sprayed at a pressure of about 100 mL to form a powder compact in the desired shape.Usually, in order to form a wide surface or band-shaped compact film, a plurality of thin tubes are formed into a bundle. composition.

In the above embodiment, the mixed powder obtained by being discharged into the discharge chamber (3) and accumulated in large quantities is taken out to the outside as appropriate.
By simply applying a predetermined pressure in the air or in a vacuum, it becomes a solid mass of a uniformly mixed predetermined structure as a structural material,
Alternatively, this mixed powder can be used for other appropriate applications such as magnetic powder in the electronics industry.

In the mixing method of the present invention, in the above embodiment, the ultrafine particles generated by evaporation of the material are directly introduced into the conveying pipe and mixed. However, in advance, each of the generated ultrafine particles is The material prepared in the container may be used as a transport material.

In this way, according to the present invention, two or more types of ultrafine particles are conveyed through the conveyance pipe by a carrier gas, and their respective conveyance flows are merged in the same direction, so that the ultrafine particles are extremely uniformly mixed. It has the effect of producing a mixed powder of metals and metals that cannot be evaporated in the same evaporation chamber, and metals and metal compounds that cannot be evaporated in the same evaporation chamber.
Furthermore, by transporting the ultrafine particles using a carrier gas, the productivity of the mixed powder is improved.

[Brief explanation of drawings]

Fig. 1 is a partially cut-away side view of a mixing device as an example of water spraying, Fig. 2 is a blending characteristic curve of mixed components obtained by XII analysis of mixed powder produced by water spraying, and Fig. 3 is a prior art technique. 4 is a side view of the mixing device of another example, and FIG. 5 is a graph showing the mixture obtained by the mixing device of FIG. 4. 6 is a similar blending characteristic curve diagram of a mixed powder obtained by a prior art mixing device; FIG. 7 is a side view of a mixing device according to another embodiment; FIG. The figure is a blending characteristic curve of the mixed powder obtained by the apparatus shown in Figure 7, Figures 9 to 12 are cut-away side views of a part of each apparatus for modified examples of the mixing method, and Figure 13 is a diagram of the discharge chamber. A side view of the modified example, and FIG. 14 shows its top view. (1)...First ultrafine particle generation chamber (2)...Second ultrafine particle generation chamber (3)...Release chamber (13(+41...Carrier gas introduction pipe■...First
Conveying pipe■...Second conveying pipe [phase]...Double pipe section■...Third ultrafine particle generation chamber■...Third conveying pipe■...Double pipe section Patent application New Technology Development Project Renewal Permit Application Hitobuchi 1) Eiji Patent Application Hito Kashu Makoto - Department Figure 1 Figure 3 Figure 2 Figure 5 Figure 6

Claims (1)

[Claims] 1. At least two types of ultrafine particles are transported and introduced into respective transport pipes using a carrier gas, and these transport pipes are oriented in the same transport direction and overlapped or combined, and the overlapped or combined parts are A method for mixing ultrafine particles, characterized in that the transport flows of the at least two types of ultrafine particles are merged in the same flow direction at the leading end to mix the at least two types of ultrafine particles. 2. A container that is provided with at least two ultrafine particle generation chambers and each chamber contains different types of materials to be evaporated;
In addition to providing a heating device to heat these materials, a vacuum device to evacuate each chamber, a carrier gas introduction pipe to be introduced into each chamber, and a conveyance pipe led out from each chamber,
Mixing of at least two types of ultrafine particles by overlapping or combining two or more transport pipes led out from the respective generation chambers facing the same transport direction and extending to the tip of the overlapping part or the combined part. An ultrafine particle mixing device consisting of a conveyor pipe connected to a mixed ultrafine particle discharge chamber. 3. The mixing device according to claim 2, wherein the overlapping portion is configured such that at least one conveying tube extends in parallel within one conveying tube and has an open end. 4. The mixing device according to claim 2, wherein the overlapping portion is configured such that at least one conveying tube extends concentrically within one conveying tube and has an open end. 5. Claims characterized in that the combined portion combines at least two transport pipes into one mixing transport pipe, and the angle between the transport pipes is 45° or less. 6. Claims (2), (4), in which the discharge chamber is connected to the green compact forming chamber through at least one nozzle pipe.
The mixing device according to any one of 5).