JP2820089B2 - Soaking heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soaking apparatus, for example, to an in-situ observing apparatus using X-rays.

[0002]

2. Description of the Related Art Conventionally, a soaking apparatus has been used for soaking and solidifying materials in a microgravity environment such as an artificial satellite, a falling wing, and an aircraft experiment in order to obtain a higher soaking temperature. Have been done. In general, for example, for experimental purposes, a material is precisely and uniformly melted in a certain specified range to carry out crystal growth, and various physical / chemical phenomena in the molten material are observed. In a heating and melting furnace having such a purpose, there is a soaking and heating furnace which can form a molten state of a test material by using a metal heating resistor as a resistance heating body.

[0003] As a soaking furnace of the prior art 1, there is one shown in FIG. In the conventional soaking furnace, the test sample 7 is supported by a heat insulating material 10 or the like, or the test sample is supported by the heat insulating material 10 in a container such as a crucible or the like, and a metal for heating is used. It comprises a metal resistance wire heater 8 wound with a resistance wire, and a reflector 9 for reducing heat leakage due to radiation.

[0004] In some cases, a diffusion layer for diffusing heat input from a heater may be arranged outside the test sample for the purpose of improving the uniform heating property of the test sample 7 or the metal resistance wire 8 may be provided. For example, a heat insulating layer is provided outside. Depending on the case, a structure in which a heat insulating layer or a reflector is provided in multiple layers or a vacuum layer for heat insulation is further provided.

[0005] As a soaking furnace of the prior art example 2, an actual heating furnace 4
No. 85100, "Molten metal observation device in space environment"
There is. In this conventional example, X-rays are transmitted through the left and right openings of the cylindrical shape using a cylindrical heating pair.

[0006]

However, in the technique of the prior art 1 for use on the ground, as shown in FIG. 2, a metal resistance wire is used as a resistance heating element. In this case, as the heating temperature range of the heating and melting furnace is set higher, it is necessary to use a resistance wire having a large specific gravity, such as Kanthal, and to use a wire having a large wire diameter to allow a large current to flow. For this reason, it is difficult to remove the image of the metal resistance wire in order to arrange the X-ray generator 11 and the X-ray detector 12 and observe the state of the test sample in-situ with X-rays.

Further, when the observation window is provided without wrapping the metal resistance wire around the X-ray transmission path as in Conventional Example 2, there is a problem that the uniform heating performance of the test sample is significantly impaired. .

[0008] It is an object of the present invention to provide a soaking apparatus capable of in-situ observation with highly uniform X-rays.

[0009]

In order to achieve the above object, a soaking apparatus of the present invention comprises a tub furnace made of a heat insulating material for accommodating a test sample, and a form surrounding the tub furnace. A ceramic heater, a protective wall surrounding the outside of the ceramic heater and formed of a heat insulating material, X-ray generating means for irradiating X-rays from one outside of the protective wall to the other outside, and the other Having a detector for receiving X-rays on the outside, heating the test sample housed in the pot furnace with a ceramic heater, and enabling in-situ observation of the test sample with the X-ray generating means and the detector It is characterized by:

[0010] Further, the above ceramic heater is composed of PG and P
It is preferable to use BN and form a plate.

Therefore, according to the soaking apparatus of the present invention, the test sample is accommodated in a tub furnace made of a heat insulating material, the tub furnace is surrounded by a ceramic heater, and the outer periphery of the ceramic heater is made of a heat insulating material. Surrounded by the formed protection wall, X-rays are emitted from one outside of the protection wall to the other outside, and received at the outside of the other. According to this configuration,
A test sample accommodated in a pot furnace is heated by a ceramic heater, and X-rays enable in-situ observation of the test sample. The difference in specific gravity between the electric resistance layer and the heat insulating layer is very small, and the absolute value of the specific gravity is low. Obtainable.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a soaking apparatus according to the present invention. FIG.
Referring to FIG. 1, there is shown an embodiment of a soaking apparatus according to the present invention. FIG. 1 shows an overall perspective view of an equalizing heating apparatus according to an embodiment in which the heating furnace is partially broken to show an internal structure, and a top view of the heating furnace.

In FIG. 1, the soaking apparatus of this embodiment comprises a heating furnace, an X-ray generator 5 and an X-ray detector 6. The heating furnace is further subdivided, and a heat insulating material 4 forming a so-called cylindrical tub for accommodating the test sample, and a ceramic heater 2 formed in a cylindrical shape on the outer periphery of the heat insulating material 4 to melt the test sample 1; And a reflector 3 provided on the outer periphery of the ceramic heater 2 and constituting a wall for heat retention and heat insulation.

Each component described above supports the test sample 1 with a heat insulating material 4 and has a ceramic heater 2 for heating on the outside thereof.
, A reflector 3 for reducing heat leakage due to radiation, and an X-ray generator 5 and an X-ray detector 6 for performing observation during melting of a test sample. ing.

In the above configuration, the positional relationship between the heating furnace, the X-ray generator 5 and the X-ray detector 6 is determined by the X-ray generator 5 for irradiating X-rays and the X-ray detector 6 for receiving X-rays. Each center axis is the center of the test sample of the heating furnace.

The ceramic heater 2 is composed of two types of ceramics produced by CVD (chemical vapor deposition). As a specific example, one is electrically conductive PG (Pyrolitic Graphaite) and the other is PBN (Pyrolit Graphite).
ic Boron Nitride). A resistance pattern is constituted by PG, and a plate-like high-temperature heater sandwiched by PBN is used.

In this configuration, the specific gravity of PBN is 2.1
5. The specific gravity difference is very small, with the specific gravity of PG being about 2.20. Further, when compared with a metal resistance wire conventionally used, the specific gravity is as small as several tenths and the absolute value is small. Because of this feature, it is easy to transmit X-ray, and when X-ray traverses the heating furnace,
The effect of the pattern of the ceramic heater 2 on the transmitted X-rays is small. Therefore, an X-ray image with high definition can be obtained,
This enables in-situ observation of the molten state of a test sample with high precision without providing an observation window. Further, the degree of consideration required for the arrangement and configuration of the ceramic heater 2 for observation is reduced.

As described above, according to the present invention, by using a ceramic heater as a heating source, external observation by X-rays can be performed without providing an observation window which is a disturbance of soaking in heating a test sample. To Further, it is possible to melt a material accurately and uniformly within a certain specified range for experimental use, perform crystal growth, and observe various physical / chemical phenomena in the molten material. By using a ceramic heater for the resistance heating element, the molten state of the test material can be observed in-situ using an X-ray transmission imaging apparatus.

Although the above embodiment is a preferred embodiment of the present invention, the present invention is not limited to this embodiment, and various modifications can be made without departing from the spirit of the present invention.

[0020]

As is clear from the above description, in the soaking apparatus of the present invention, a porcelain furnace containing a test sample is surrounded by a ceramic heater, and the outer periphery of the ceramic heater is formed of a heat insulating material. Surrounded by a protective wall, X-rays are emitted from one outside of the protective wall to the other outside, and received at the other outside. With this configuration, the test sample accommodated in the pot furnace is heated by the ceramic heater, and the test sample can be observed in situ with X-rays. The ceramic heater has a very small difference in specific gravity between the electric resistance layer and the heat insulating layer as the heater, and has a low absolute value of the specific gravity. Can be obtained. ADVANTAGE OF THE INVENTION According to the soaking apparatus of this invention, high uniform heating and a clear image can be obtained.

[Brief description of the drawings]

FIG. 1 is a view showing an embodiment of a soaking apparatus according to the present invention, which is an overall perspective view of a soaking apparatus in which a heating furnace is partially broken to show an internal structure, and a top view of the heating furnace.

FIG. 2 is an external cutaway view of a conventional soaking device when a conventional heater in which a gold layer resistance wire is wound in a coil shape is used.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Test sample 2 Ceramic heater 3 Reflector 4 Insulation material 5 X-ray generator 6 X-ray detector

Claims (3)

(57) [Claims] 1. A pot furnace made of a heat insulating material for accommodating a test sample, a ceramic heater formed so as to surround the pot furnace, and a heat insulating material surrounding the outer periphery of the ceramic heater. A protection wall, X-ray generating means for irradiating X-rays from one outside of the protection wall to the other outside, and a detector for receiving the X-rays on the outside of the other side; A test sample accommodated in the sample heater is heated by the ceramic heater, and in-situ observation of the test sample is enabled by the X-ray generation means and a detector. 2. The apparatus according to claim 1, wherein the ceramic heater is formed using PG and PBN. 3. The uniform heating device according to claim 1, wherein the ceramic heater is formed in a plate shape.