JPH0673512A - Heat treatment apparatus for metallic material - Google Patents

Abstract

PURPOSE:To reduce the consumption of hydrogen while restraining the release of the hydrogen and to miniaturize an apparatus by mutually communicating plural heat treatment furnaces for executing occlusion and release of the hydrogen in a metallic material through a communicating passage being provided with a pressure control means. CONSTITUTION:In the heat treatment apparatus 10 for executing the hydrogen occlusion treatment for occluding the hydrogen into the metallic material and the hydrogen release treatment for releasing the hydrogen from the metallic material occluding the hydrogen, plural heat treatment furnaces A, B for executing these treatments are arranged. These heat treatment furnaces A, B are communicated with a closed circuit for flowing the hydrogen. On the way of this communicating passage, the pressure control means 12 is arranged. Pressure in one side heat treatment furnace A is reduced through this pressure control means 12 to release the hydrogen, and this hydrogen pressure is risen and is supplied to the other side heat treatment furnace B to execute the hydrogen occlusion. By this method, the release of the hydrogen out of the apparatus can be suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat treatment apparatus for metal-based materials, and more particularly, to occlude hydrogen in the metal-based material and release hydrogen from the metal-based material that has occluded the hydrogen. The present invention relates to a heat treatment apparatus in which the structure of a metal-based material is changed to adjust the physical properties or the metal-based material is crushed.

[0002]

2. Description of the Related Art Conventionally, for example, adjustment of physical properties of metal-based materials (for example, improvement of magnetic properties by refinement of crystal grains of rare earth (R) -iron (Fe) -boron (B) alloy, or titanium (Ti)). ) As a method of improving fatigue strength and creep resistance by coarsening the structure of a system alloy, as described above, hydrogen is absorbed in the metal-based material at a certain processing temperature, and then the hydrogen is again stored. The metal structure is changed by releasing the heat treatment, and conventionally, as the heat treatment apparatus thereof, the one having the structure shown in FIG. 5 has been studied.

In this heat treatment apparatus 1, a metal-based material W is carried in and a heat treatment furnace 2 for heating the metal-based material W to a predetermined treatment temperature is connected to the heat treatment furnace 2 through an air supply passage 3. Hydrogen cylinder 4 for storing hydrogen for reaction
And an exhaust means 5 connected to the heat treatment furnace 2 for sucking and exhausting the gas in the heat treatment furnace 2, and an exhaust treatment means for incinerating the gas exhausted by the exhaust means 5 and discharging it to the outside of the apparatus. In the hydrogen cylinder 4, the volume efficiency of storage is increased by cooling the hydrogen and liquefying it.

In the heat treatment apparatus 1, after the metallic material W is carried into the heat treatment furnace 2, hydrogen is supplied from the hydrogen cylinder 4 into the heat treatment furnace 2 and the heat treatment furnace 2 is heated. By maintaining the temperature at 500 ° C. to 1000 ° C., the metal-based material W is heated to a predetermined temperature in a hydrogen gas atmosphere to occlude hydrogen, and then the temperature in the heat treatment furnace 2 is maintained at the temperature. While
By depressurizing the inside of the heat treatment furnace 2 to a vacuum state, hydrogen is released from the metal-based material W that has occluded hydrogen.

Further, the hydrogen released from the metallic material W is sucked from the heat treatment furnace 2 by the exhaust means 5, incinerated by the exhaust processing means 6 at the subsequent stage, and then released to the outside of the apparatus. Has become.

[0006]

By the way, in the above-mentioned conventional technique, hydrogen used for the heat treatment of the metallic material W is supplied from the hydrogen cylinder 4 to the heat treatment furnace 2 and then passes through the exhaust treatment means 6. Since it is released to the atmosphere, new hydrogen must be supplied for each processing step, resulting in a huge amount of hydrogen consumption. Therefore, there is a problem that a large capacity hydrogen cylinder 4 is required.

On the other hand, as a method of coping with such a problem, for example, returning hydrogen discharged from the heat treatment furnace 2 to the hydrogen cylinder 4 on the supply side can be considered.

However, even in such a method, a liquefaction processing facility for returning once vaporized hydrogen to a liquid is required, and the cooled hydrogen must be heated again before it is used. It is not an effective solution because it increases in size as a whole and causes a rise in the construction cost of the treatment facility.

In particular, in order to improve the productivity, when the heat treatment is carried out by using a plurality of heat treatment furnaces 2, it is necessary to provide a hydrogen supply system for each heat treatment furnace. The amount further increases, and accordingly, the equipment becomes larger.

[0010]

DISCLOSURE OF THE INVENTION The present invention is to provide a heat treatment apparatus for a metal-based material which can effectively solve the above-mentioned problems in the prior art. In particular, the metal-based material absorbs hydrogen. A plurality of heat treatment furnaces for performing hydrogen storage treatment for causing hydrogen release processing for releasing hydrogen from the metal material that has stored hydrogen, and for communicating hydrogen between the heat treatment furnaces by connecting these heat treatment furnaces to each other. And a communication passage that forms a closed circuit of the heat treatment furnace, which is provided in the middle of the communication passage to increase the pressure inside and supply hydrogen when the heat treatment furnace performs hydrogen storage processing, and these heat treatment furnaces A pressure control means for discharging hydrogen while decompressing the inside of the hydrogen release processing, wherein the pressure control means is a vacuum exhaust means, and the pressure control means is true Characterized in that it is constituted by the exhaust means and the pressure regulating means provided on the exhaust side.

[0011]

According to the heat treatment apparatus for a metal-based material of the present invention, when one heat treatment furnace is in the step of storing hydrogen in the metal-based material, the heat treatment furnace is heated to a predetermined temperature and then Hydrogen is supplied to the inside by pressure control means,
And, the internal pressure is increased to a predetermined pressure, and by this,
In the heat treatment furnace, the hydrogen absorption phenomenon of the metallic material occurs,
Hydrogen storage processing of the metal-based material is performed.

When the hydrogen storage treatment in one heat treatment furnace is completed and the treatment in this heat treatment furnace is switched to the hydrogen desorption treatment, the hydrogen in this heat treatment furnace is sucked and discharged by the pressure control means, and As the hydrogen is discharged, the pressure inside the heat treatment furnace is reduced. As a result, hydrogen is released from the metal-based material in the heat treatment furnace, and the hydrogen release process is performed on the metal-based material.

On the other hand, while the hydrogen releasing process is being performed in one heat treatment furnace in this way, in the other heat treatment furnaces connected to this heat treatment furnace via the communication passage, the inside thereof is heated to a predetermined temperature. Preparations for heating and hydrogen storage treatment are performed in parallel, and when the hydrogen desorption treatment in one heat treatment furnace is completed or in parallel, the pressure control means sucked from one heat treatment furnace. Hydrogen is sent to another heat treatment furnace.

As a result, the internal pressure increasing operation and the hydrogen filling operation for the other heat treatment furnaces are performed, and the hydrogen storage processing is performed in the other heat treatment furnaces.

As described above, in the present invention, the hydrogen used for the heat treatment of the metallic material is exchanged between the respective heat treatment furnaces, the release to the outside of the apparatus is suppressed, and the amount of hydrogen required for one unit is controlled by the hydrogen. It becomes possible to perform heat treatment in at least two or more heat treatment furnaces, and it is possible to reduce the amount of hydrogen used and suppress the enlargement of the apparatus.

[0016]

EXAMPLE A first example of the present invention will be described below with reference to FIG. 1. The heat treatment apparatus 10 for a metal-based material according to the present example is a hydrogen storage device for storing hydrogen in the metal-based material W. A plurality of (two in this embodiment) heat treatment furnaces A and B for performing the treatment and hydrogen release treatment for releasing hydrogen from the metal-based material W that has occluded hydrogen and these heat treatment furnaces A and B are mutually connected. And a communication passage 11 which forms a closed circuit for hydrogen flow between the heat treatment furnaces A and B, and the communication passage 1
When the heat treatment furnace A (B) is provided in the middle of 1, the pressure inside the heat treatment furnace A (B) is increased and hydrogen is supplied, and the heat treatment furnaces A and B perform hydrogen desorption treatment. At this time, the pressure control means 12 for depressurizing the inside and discharging hydrogen is also provided.

Next, to explain these details, each of the heat treatment furnaces A and B in the present embodiment has a preheating chamber 13 for heating the metallic material W prior to the heat treatment,
A heat treatment chamber 14 that is connected to the preheating chamber 13 and performs hydrogen storage treatment and hydrogen desorption treatment of the metal-based material W, and a heat treatment chamber that is connected to the heat treatment chamber 14 and is carried out from the heat treatment chamber 14 Cooling chamber 1 for cooling the metallic material W of
5, the preheating chamber 13, the heat treatment chamber 14, and the cooling chamber 15 can communicate with each other and can be shielded from each other. The heat treatment furnaces A and B are
An internal heating type in which a heater made of graphite, tungsten, molybdenum, or the like is provided inside the vacuum container, or an external heating type in which a heater such as cantal or silicon knit is provided outside the vacuum container is used.

The communication passage 11 is formed by the heat treatment furnaces A and B.
The heat control chambers 14 are provided so as to communicate with each other, and the pressure control means 12 is provided in the middle thereof so that the two heat treatment chambers 14 are airtightly communicated with each other, and hydrogen which is isolated from the outside air is provided therebetween. To form a closed circuit.

The pressure control means 12 is configured to increase or decrease its volume and does not exchange gas with the outside of the apparatus, for example, a cylinder is used, and the pressure control of the communication passage 11 is performed. By the action of the on-off valves 16 and 17 provided on both sides of the means 12, the heat treatment chambers 14 are selectively communicated with one of the heat treatment chambers 14 of the both heat treatment furnaces A and B, and these heat treatment chambers 14 are communicated with each other. By increasing the volume of each of the heat treatment chambers 14, the inside of each heat treatment chamber 14 is decompressed and hydrogen is taken in, and by reducing the volume of each heat treatment chamber 14, the inside of each heat treatment chamber 14 is pressurized and hydrogen is sent into the inside thereof. ing.

The control of the internal temperature and internal pressure of each heat treatment chamber 14 and the operation control of the pressure control means 12 and the on-off valves 16 and 17 are preset by a control means such as a microcomputer (not shown). It is controlled by the temperature, pressure and procedure.

On the other hand, the composition of the metallic material W to be heat-treated in this embodiment is, for example, as follows.

One of them is an R-Fe-B type alloy having the following composition. R: 10 to 20 at% B: 3 to 10 at% Fe: balance and unavoidable impurities The following composition is added as necessary. Co: 0.1 to 50 at% M: 0.001 to 5.0 at% However, M is Al, Si, Ga, Ti, V, Cr, Zr,
One or two of Nb, Mo, Hf, Ta, W, C, N
More than a seed.

The other one is a Ti-based alloy structural material, for example, the following alloy compositions can be mentioned.

1) Al: 6.5 wt%, Sn: 1.4 w
t%, Zr: 1 wt%, Mo: 2.9 wt%, Cr:
2.1 wt%, Fe: 1.7 wt%, and the balance T
i is an alloy 2) Al: 6 wt%, V: 4 wt%, and the balance is T
Alloy which is i 3) Al: 6 wt%, Sn: 2 wt%, Zr: 4 wt
%, Mo: 2 wt%, and an alloy in which the balance is Ti 4) V: 10 wt%, Fe: 2 wt%, Al: 3 wt
%, And the alloy with the balance being Ti

Besides, Zr--Co type, Ti--Fe type, (T
It can also be used as an activation treatment or a powdering treatment for a hydrogen storage alloy such as an i, Zr) -Ni-based alloy or a rare earth (R) -Ni-based alloy.

A specific example of heat treatment of the metallic material W in the heat treatment apparatus 10 of the present embodiment configured as described above will be described based on two experimental examples performed for each of the two compositions. The explanation is as follows.

(Experimental Example 1) First, an example using the former R-Fe-B alloy as the metal-based material W used for the heat treatment will be described.

R-Fe-B alloys having the compositions shown in Tables 1 to 4 were melted in a plasma arc melting furnace and then cast, and then, respectively, in Ar atmosphere at 1130 ° C. and 2
Homogenization is performed under the condition of 0 hours. This metallic material W
Has a coarse ferromagnetic phase with a grain size of about 120 μm.

[0029]

[Table 1]

Such a metallic material W is preheated in a vacuum state in a preheating chamber 13 of a heat treatment furnace A equipped with one external heating type Kanthal wire heater, and then installed in the heat treatment chamber 14 in a vacuum state. Then, the preheating chamber 13 and the heat treatment chamber 14 are hermetically shielded, and the internal heating of the heat treatment chamber 14 is started.

On the other hand, the internal temperature of the heat treatment chamber 14 is detected by a temperature sensor provided in each of them and fed back to the control means. Based on this feedback signal, the internal temperature of the heat treatment chamber 14 is a predetermined temperature. It is maintained at (about 300 ° C.).

At the initial stage of operation, a predetermined amount of hydrogen is supplied to the heat treatment chamber 14 of the one heat treatment furnace A from a separately provided hydrogen storage means or the like under a predetermined pressure (about 1 atm or less). Sent in. Here, the internal pressure of the heat treatment furnace A heat treatment chamber 14 is detected by a pressure sensor and fed back to the control means, and is kept at the above-mentioned pressure based on this feedback signal.

After the supply of hydrogen is completed, the temperature in the heat treatment furnace A is raised by the control means to about 830 ° C.
The metal-based material W is held at the temperature for about 3 hours, whereby hydrogen is occluded in the metal-based material W.

Next, the temperature in the heat treatment furnace A is set to 830
In the state where the heat treatment chamber 1 of the one heat treatment furnace A is output, a drive signal is output from the control device to the one on-off valve 16 in a state of being kept at ℃.
4 is made to communicate with each other, and a drive signal is output to the pressure control means 12 to operate so as to suck the gas in the heat treatment furnace A.

As a result, the pressure inside the heat treatment furnace A is reduced, and the hydrogen inside the furnace is controlled by the pressure control means 1.
By being sucked into 2, in the heat treatment furnace A,
The hydrogen stored in the metal-based material W is released to dehydrogenate the metal-based material W, and after the dehydrogenation treatment is performed in this way, the on-off valve 16 is closed and the heat treatment furnace The communication between the heat treatment chamber 14 of A and the pressure control means 12 is cut off.

The pressure in the heat treatment furnace A at this time is 1 × 10 ^-1 Torr by the detection signal from the pressure sensor and the control of the operation amount of the pressure control means 12 by the control means based on this detection signal. It is retained below.

By the way, the Nd-Fe-B alloys having the above-mentioned respective compositions after this treatment are pulverized to 400 μm or less, and 0.2 to 0.4 μm of Nd 2 Fe is contained inside the powder.
It was confirmed that it has a structure composed of recrystallized grains of 14B and has desired magnetic properties.

Further, the metallic material W in the heat treatment furnace A
In parallel with the hydrogen release process of No. 1, in the other heat treatment furnace B, a new metal-based material W is preheated and then carried into the heat treatment chamber 14 and heated to a predetermined temperature in the heat treatment chamber 14. As a result, the hydrogen storage process is enabled.

From this, the other on-off valve 1 is controlled by the control means.
7 is opened and the pressure control means 12 is operated, whereby the hydrogen sucked by the pressure control means 12 is sent to the heat treatment chamber 14 of the other heat treatment furnace B under the above-mentioned predetermined pressure. Then, the hydrogen storage treatment is performed in the other heat treatment furnace B, and after the hydrogen storage treatment is completed, the pressure control means 12 is operated in the reverse direction to cause the other heat treatment furnace B to be operated.
The hydrogen released in the heat treatment furnace B is discharged by sucking the hydrogen.

After the heat treatment of the metallic material W in the other heat treatment furnace B is completed, the other open / close valve 17
When the other heat treatment furnace B is closed, the communication between the other heat treatment furnace B and the pressure control means 12 is cut off.
The heat treatment of the metal-based material W in step 1 is completed.

As described above, in the heat treatment apparatus 10 of this embodiment, the hydrogen used for the heat treatment of the metallic material W is
It is exchanged with the heat treatment furnaces A and B through the pressure adjusting means 12 to suppress the release of hydrogen to the outside of the apparatus, so that the amount of hydrogen used is greatly reduced and the exhaust treatment system Since various equipments are not required, it is possible to suppress the increase in size of equipment or soaring of equipment cost, and moreover, the two heat treatment furnaces A and B can be operated by the amount of hydrogen for one charged at the initial stage of operation. Therefore, also from this point, the enlargement of the device is suppressed.

Then, the metallic material W is put into and taken out of each of the heat treatment furnaces A and B, for example, the preheating chamber 13 and the cooling chamber 1.
It is conceivable that hydrogen used in the heat treatment leaks to the outside when the heat treatment chamber 14 is moved in and out of the heat treatment chamber 5 and when the heat treatment chamber 14 is evacuated, and the amount of hydrogen in the apparatus is reduced by repeating the heat treatment. However, the amount of decrease is extremely small, and even if the amount of decrease is less than the amount required for heat treatment, it can be dealt with just by supplementing the amount of decrease, and the hydrogen storage facility has a small capacity. OK.

Here, in the heat treatment apparatus 10 of the present embodiment, the initial hydrogen filling amount was set to 35 Nm ^3, and the amount of hydrogen reduction after the metal-based material W of each composition was treated 10 times. The results of the measurement are shown in the left column of Table 2.

[0044]

[Table 2]

The right column of Table 2 shows, for comparison, the remaining amount of hydrogen when the same metal-based material W is heat-treated by a conventional apparatus.

As is clear from this result, according to the present experimental example, almost no decrease in hydrogen was observed, and an extremely large effect was obtained.

(Experimental Example 2) Next, an experimental example using the latter Ti-based alloy as the metal-based material W will be described.

First, with respect to each of the Ti-based alloy powders having the composition shown by 1.2 in Table 3 and having an average particle diameter of 120 μm, hot isostatic pressure was applied under the conditions of temperature of 750 ° C., 2000 atm, and holding for 3 hours. By pressing, a structural member as the metal-based material W having a predetermined shape was created.

[0049]

[Table 3]

This metallic material W is installed in a heat treatment furnace A (B) equipped with an internal heat type graphite heater, and each component of the heat treatment apparatus 10 is operated by a control means, similar to the above embodiment. 850 ℃, 1atm
In the above atmosphere, the metal-based material W was allowed to absorb hydrogen, and then the metal-based material W was dehydrogenated under the conditions of 850 ° C. and 1 × 10 ⁻⁴ Torr.

By such heat treatment, the coarse α
A Ti-based alloy having a + β phase is obtained, and the Ti-based alloy having such a composition is excellent in high cycle fatigue strength and creep resistance. Also in this case, the hydrogen used for the heat treatment is transferred between the heat treatment furnaces A and B via the pressure control means 12, so that the leakage of hydrogen to the outside of the apparatus is suppressed. .

Here, the hydrogen filling amount in the initial state is set to 35 Nm.
^The result of measuring the amount of hydrogen reduction when each of the Ti-based alloys was subjected to the above treatment 20 times by the apparatus of this example set forth in ³ is shown in the left column of Table 4, and the right side of Table 4 is shown. For comparison, the column shows the amount of hydrogen reduction when each of the Ti-based alloys of this example was heat-treated using a conventional apparatus.

[0053]

[Table 4]

As is clear from this result, there is no reduction in hydrogen in this experimental example as well, which is a significant improvement over the conventional apparatus.

On the other hand, FIG. 2 shows a second embodiment of the present invention. The heat treatment apparatus 20 of the present embodiment has the two heat treatment furnaces A and B shown in the above-mentioned embodiment and another one. The heat treatment furnace C is added.

In this embodiment, the heat treatment chamber 14 of each of the heat treatment furnaces A to C has a plurality of communication passages 11 (11a.1).
1b, 11c) and the pressure control means 12 (12a, 12b, 12) similar to those in the above-mentioned embodiment are provided in the middle of the respective communication passages 11a, 11b, 11c.
c) and a pair of open / close valves 16 (16a, 16b, 16c).
17 (17a, 17b, 17c) are provided.

The heat treatment apparatus 20 thus constructed is
Each pressure control means 12a, 12b, 12c and on-off valve 1
6 (16a, 16b, 16c), 17 (17a, 17b)
By sequentially controlling the operation of 17c), hydrogen is sent from the heat treatment furnace A to the heat treatment furnace B, then from this heat treatment furnace B to the heat treatment furnace C, and further from this heat treatment furnace B to the heat treatment furnace C. By circulating the metal material W in each of the heat treatment furnaces A, B, and C, hydrogen storage processing and hydrogen desorption processing are sequentially performed.

The heat treatment apparatus 2 in this embodiment as described above
Even in 0, since the hydrogen used for heat treatment is circulated between the heat treatment furnaces A, B, and C, and leakage to the outside of the apparatus is suppressed, the amount of hydrogen used is greatly reduced and If the processing cycles of the heat treatment furnaces A, B, and C (carry-in process, preheat process, hydrogen storage process, hydrogen desorption process, cooling process, and carry-out process) do not overlap in time, the amount of hydrogen for one unit is 3 The base heat treatment furnaces A, B, and C can be operated, and the apparatus can be downsized as compared with the case where the three heat treatment furnaces A, B, and C are operated independently in parallel.

FIG. 3 shows a third embodiment of the present invention. The heat treatment apparatus 30 shown in this embodiment is different from each heat treatment furnace A.
The heat treatment chamber 14 of B is connected by the two communication passages 31 and 32, and the middle of each of the communication passages 31 and 32 is connected to the vacuum evacuation means 33 which constitutes the pressure control means 12 shown in the first embodiment. Connected and each communication passage 31, 32
In the middle of the
-It has a structure provided with 35.

In the heat treatment apparatus 30 of the present embodiment having the above-described structure, the heat treatment in each of the heat treatment furnaces A and B is the same as that of the first embodiment, but the hydrogen between the heat treatment furnaces A and B is changed. There are differences in the circulation method.

That is, for example, when the hydrogen storage process is completed in the heat treatment furnace A, first of the two on-off valves in the closed state, the on-off valve 34 arranged between the vacuum evacuation means 33 and the heat treatment furnace A. Is opened and the vacuum evacuation means 33 is operated, so that the gas in the heat treatment furnace A is sucked and sent to another heat treatment furnace B.

As a result, in the heat treatment furnace A, the internal pressure of the heat treatment chamber 14 is reduced and hydrogen release is reduced, and the released hydrogen is sent to the other heat treatment furnace B by the vacuum exhaust means 33, and The internal pressure of the heat treatment chamber 14 of the heat treatment furnace B is increased, so that the hydrogen storage process is performed in the other heat treatment furnace B.

Here, the pressure of hydrogen sent to the other heat treatment furnace B is based on a feedback signal relating to the internal pressure of the heat treatment chamber 14 of the heat treatment furnace B detected by the pressure sensor, and the operation of the vacuum evacuation means 33. By controlling the amount, it is adjusted to the same value as in the above-mentioned embodiment.

Next, the opened on-off valve 34 is closed to keep the other heat treatment furnace B in a closed state, and after the time required for hydrogen storage elapses, the other on-off valve 35 is opened. Along with being opened, the vacuum exhaust means 33
Is operated, hydrogen in the heat treatment chamber 14 of the other heat treatment furnace B is sucked and sent to the heat treatment chamber 14 of one heat treatment furnace A, and in the other heat treatment furnace B, due to the same phenomenon as described above, Hydrogen release processing is performed, and hydrogen storage processing is started in one heat treatment furnace A.

By repeating the above operation, the heat treatment of the metal-based material W is alternately performed in each of the heat treatment furnaces A and B. In the present embodiment, the heat treatment is performed in the same manner as in the first embodiment. The hydrogen used is only exchanged between the two heat treatment furnaces, and leakage to the outside of the equipment is suppressed, which reduces the amount of hydrogen used and allows the two heat treatment furnaces to operate with one unit of hydrogen. In addition, the hydrogen storage means has a small capacity, and the enlargement of the device is suppressed.

Further, in the present embodiment, when one of the heat treatment furnaces A is in the hydrogen release processing state, the vacuum evacuation means 33 forcibly sucks hydrogen from the heat treatment furnace A and stores the hydrogen therein. By forcibly feeding into another heat treatment furnace B in the treatment state and increasing the internal pressure thereof, the decompression treatment in one heat treatment furnace A and the pressure increase treatment in the other heat treatment furnace B, and the hydrogen between By performing the movement simultaneously and forcibly, each of these processes can be performed reliably and quickly.

Further, FIG. 4 shows a fourth embodiment of the present invention. In the heat treatment apparatus 40 shown in the present embodiment, an example in which the pressure control means 12 is the vacuum exhaust means 33 in the third embodiment is described. Instead of the one shown, the pressure control means 12 is further constituted by a vacuum evacuation means 33 and a pressure adjusting means 41 provided on the evacuation side thereof, and the rest of the configuration is the same as that of the third embodiment. It is the same.

The operation of this embodiment is almost the same as that of the third embodiment, but in the third embodiment, the supply pressure of hydrogen (in other words, by controlling the operation amount of the vacuum evacuation means 33). While the internal pressure in the heat treatment chamber 14 of the heat treatment furnace in the hydrogen storage processing state is adjusted, in the present embodiment, the pressure adjusting means 41 is used.
The feature is that the adjustment is performed by.

With this structure, the supply pressure of the hydrogen can be finely and highly accurately adjusted, and the supply pressure can be adjusted and the hydrogen is sucked to release hydrogen. The stability of heat treatment is ensured by being independent of the depressurizing action of the heat treatment furnace.

The above-mentioned embodiments are merely examples, and various modifications can be made based on the type of metallic material to be applied, design requirements, and the like. For example, in each of the above-mentioned embodiments, an example of using hydrogen alone for the heat treatment is shown, but instead of this,
It is also possible to use a mixed gas with an inert gas, and in this case, the hydrogen partial pressure of the mixed gas may be used as a control factor for pressure control.

Also in the third and fourth embodiments, as in the second embodiment, it is possible to provide three or more heat treatment furnaces.

[0072]

As described above, the heat treatment apparatus for metallic materials according to the present invention has the following excellent effects.

A closed circuit for exchanging hydrogen between the plurality of heat treatment furnaces is formed so that the hydrogen can be exchanged between the plurality of heat treatment furnaces and can be repeatedly used. The heat treatment furnace can be operated with the required amount of hydrogen, the productivity can be improved, the amount of hydrogen used can be reduced, and the increase in size of the apparatus can be suppressed.

Further, it is not necessary to additionally provide a means for storing hydrogen used for heat treatment, and from this point as well, it is possible to suppress the enlargement of the apparatus.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a block diagram showing a second embodiment of the present invention.

FIG. 3 is a block diagram showing a third embodiment of the present invention.

FIG. 4 is a block diagram showing a fourth embodiment of the present invention.

FIG. 5 is a block diagram showing a conventional example.

[Explanation of symbols]

 10 heat treatment apparatus 11 communication passage 12 pressure control means 20 heat treatment apparatus 30 heat treatment apparatus 31 communication passage 32 communication passage 33 vacuum evacuation means 40 heat treatment apparatus 41 pressure adjusting means A heat treatment furnace B heat treatment furnace C heat treatment furnace W metallic material

Claims (3)

[Claims] 1. A plurality of heat treatment furnaces that perform a hydrogen storage process of storing hydrogen in a metal-based material and a hydrogen release process of releasing hydrogen from the metal-based material that stores hydrogen, and these heat treatment furnaces are mutually connected. A communication passage that is communicated with each other to form a closed circuit for hydrogen flow between the heat treatment furnaces, and is provided in the middle of the communication passage to increase the pressure inside the heat treatment furnace when performing the hydrogen storage treatment. Supply hydrogen and
A heat treatment apparatus for a metal-based material, characterized in that these heat treatment furnaces are provided with pressure control means for decompressing the inside of the heat treatment furnace and discharging hydrogen during the hydrogen release treatment. 2. The heat treatment apparatus for a metal-based material according to claim 1, wherein the pressure control means is an evacuation means. 3. The heat treatment apparatus for a metal-based material according to claim 1, wherein the pressure control means is composed of vacuum evacuation means and pressure adjusting means provided on the evacuation side thereof.