JP3327161B2 - Regenerator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a Stirling type,
In regenerators of various refrigerators such as a GM (Gihod McMan) type and a pulse tube type, the regenerator material to be filled is 25 to 50 at% containing at least one or two or more elements from the viewpoint of improvement of refrigerating capacity. A magnetic material comprising a rare earth element and a 50 to 75 at% additive containing at least Ga.
The present invention relates to a regenerator that improves cold storage efficiency at 0K or less.

[0002]

2. Description of the Related Art A conventional first regenerator uses an alloy such as copper or lead as a regenerator material to be filled therein, and cools at 20K or more by specific heat of a lattice system.

A conventional second regenerator (Japanese Patent Laid-Open No. 1-3102)
69) uses a magnetic material made of Er ₃ Ni having not only a lattice specific heat but also a spin specific heat as a cold storage material to be filled therein, and a cold storage material made of an alloy such as copper or lead at an extremely low temperature of 20 K or less. Since the specific heat was larger, the heat storage efficiency was improved at 20K or less.

A conventional third regenerator (JP-A-6-0901)
No. 61) employs a magnetic material made of ErAg having a magnetic transition point at 10 to 30 K as a regenerator material to be filled therein, and has a large specific heat at 10 to 30 K to improve heat storage efficiency.

[0005]

[Problems to be solved by the invention]

[0006] The above-mentioned conventional first regenerator uses an alloy such as copper or lead and has a relatively large specific heat at 20 K or more due to the specific heat of the lattice system. Below, there was a problem that it was not possible to sufficiently accumulate cold heat and to reach extremely low temperatures.

The second conventional regenerator uses a magnetic material made of Er ₃ Ni having not only a lattice specific heat but also a spin specific heat, and the regenerator made of an alloy such as copper or lead at an extremely low temperature of 20 K or less. specific heat than wood is large, but to improve the heat storage efficiency in 20K or less, the Er ₃ Ni
Since the magnetic transition point of is around 8K, there was a problem that the heat storage efficiency was insufficient when the temperature was less than 10K but was insufficient in the range of 10 to 30K.

[0008] The third conventional regenerator is 10 to 3
A magnetic material made of ErAg having a magnetic transition point at 0K is employed, and the specific heat at 10 to 30K is large, so that the heat storage efficiency is improved. However, at 10K or lower, the specific heat is smaller than that of the second regenerator, and the heat storage efficiency is low. Is poor, the refrigeration output below 10K is insufficient, and He
However, there is a problem that it is insufficient for refrigeration at a temperature of 10 K or less such as liquefaction.

Therefore, the present inventors have proposed a regenerator filled with a regenerator material, wherein the regenerator material contains 25 to 50 at% rare earth element containing at least one or more elements, and at least 50 at%. Focusing on the technical idea of the present invention in which the regenerator material is constituted by a magnetic material comprising the above Ga-containing additive of 50 to 75 at% and further research and development, the specific heat at 10K or less is large. The present invention has been achieved that achieves the object of improving the cold storage efficiency at 10K or less.

[0010]

According to a first aspect of the present invention, there is provided a regenerator comprising a regenerator filled with a regenerator material, wherein the regenerator material is at least one or two types. The magnetic material comprises a rare earth element of 25 to 50 at% containing the above elements and an additive of 50 to 75 at% containing at least 50 at% of Ga.

The present invention (second invention described in claim 2)
The regenerator according to the first aspect, wherein the rare earth element is one of Ce, Pr, Nd, Gd, Dy, Ho, Er and the like.
Contains two or more species.

The present invention (the third invention described in claim 3)
The regenerator according to the second aspect, wherein the additive is:
B, Al, In, Si, Ge, Sn, Au, Mg, Z
n, Pd, Pt, Re, Cs, Ir, Fe, Mn, C
It contains at least one element of r, Cd, Hg, Os, and P.

The present invention (the fourth invention described in claim 4)
In the regenerator according to the third aspect, the content of at least one element of the additive is 5 at% or less.

The present invention (fifth invention described in claim 5)
In the regenerator according to the second and fourth aspects, the content of the rare earth element is 25 to 33 at%.

The present invention (the sixth invention described in claim 6)
In the regenerator according to the second and fourth aspects, the content of the rare earth element is 33 to 50 at%.

The present invention (seventh invention described in claim 7)
In the regenerator according to the fifth or sixth aspect, the rare earth element is Dy, and the additive is B or Al.

The present invention (the eighth invention described in claim 8)
In the regenerator according to the fifth or sixth aspect, the rare earth element is Ho or Dy.

[0018]

The regenerator according to the first aspect of the present invention, wherein the regenerator material to be filled is 25 to 50 at% rare earth element containing at least one or more elements, and at least 50 at%. % To 50 at% of an additive containing 50% to 75% of Ga, the regenerator material using the rare earth elements R and Ga is RGa2, as is apparent from FIGS.
Since a compound, an RGa2 compound and an RGa compound, and a mixed structure of an RGa2 compound and an RGa3 compound are formed, the magnetic transition point of these compounds is about 10K or less, and a specific heat peak exists near the magnetic transition point. From that large specific heat below 10K
This has the effect of improving the cold storage efficiency below K.

Here, the content of the rare earth element R is 25
In the case of at% or less and the case of 50 at% or more, the magnetic transition point is about 10 K or less, as is apparent from the phase diagrams of Dy-Ga and Ho-Ga shown in FIGS. Since no RGa ₂ compound is produced,
An improvement in specific heat of 10K or less cannot be expected.

In the regenerator according to the second aspect of the present invention, the rare earth element is Ce, Pr,
Since one or more of Nd, Gd, Dy, Ho, Er and the like are contained, the RGa ₂ compound, RGa ₂ compound and R
Since a mixed structure of a Ga compound, an RGa ₂ compound and an RGa ₃ compound is generated, the magnetic transition point of these compounds is about 10 K or less, and a specific heat peak exists near the magnetic transition point. In the following, the specific heat is large, and the effect of improving the cold storage efficiency at 10K or less is achieved.

[0021] In the regenerator according to the third aspect of the present invention, the additive according to the second aspect, wherein the additive is B, Al, In,
Si, Ge, Sn, Au, Mg, Zn, Pd, Pt, R
e, Cs, Ir, Fe, Mn, Cr, Cd, Hg, O
Since at least one element of s and P is contained, the addition of these elements has an effect that the specific heat peak can be broadened and the peak temperature can be adjusted.

In the regenerator according to the fourth aspect of the present invention, since the content of at least one element of the additive is 5 at% or less in the third aspect, the specific heat at 10 K or less is increased. This has the effect of improving the cold storage efficiency at 10K or less.

The regenerator of the fifth aspect of the present invention having the above described construction, in the second invention or the fourth invention, the content of the rare earth element, because it is 25 to 33 at%, RGa ₂
Since a mixed structure of the compound and the RGa ₃ compound is generated, it is possible to adjust the peak of specific heat according to the ratio of the mixed structure.

The regenerator of the sixth aspect of the present invention having the above described construction, in the second invention or the fourth invention, the content of the rare earth element, so to not 33 is 50at%, RGa ₂
Since a mixed structure of the compound and the RGa compound is generated, it is possible to adjust the peak of the specific heat according to the ratio of the mixed structure.

[0025] In the regenerator according to the seventh aspect of the present invention, the rare earth element is Dy in the sixth aspect,
Since the additive is B or Al, there is an effect that a plurality of peaks are formed at 10K or less, the specific heat at 10K or less is increased, and the cold storage efficiency at 10K or less is improved.

[0026] In the regenerator according to an eighth aspect of the present invention, the rare earth element is Ho or D in the fifth aspect.
Since it is y, there is an effect that a plurality of peaks are formed at 10K or less, the specific heat at 10K or less is increased, and the cold storage efficiency at 10K or less is improved.

[0027]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) In the regenerator according to the first embodiment, as shown in FIG. 7, in the regenerator 1 filled with the regenerator material 10, the regenerator material 10 has at least C.
e, 25 to 50 at% of a rare earth element containing at least one element such as Pr, Nd, Gd, Dy, Ho, Er, and 50 to 75 containing at least Ga.
at% of an additive.

As shown in FIG. 7, the regenerator 1 of the first embodiment is applied to a Stirling refrigerator as an example, and includes a radiator 4 connected to a compression chamber 3 in which a piston 21 moves up and down. The piston 22 is disposed between the heat exchanger 6 and the expansion chamber 5 that moves up and down.

The rare earth element is Ho or Dy, and the content of the rare earth element is 33 to 50 at%.
And the content of Ga in the additive is 50 to 67.
at%.

In the regenerator according to the first embodiment having the above-described structure, the regenerator material 10 to be filled contains at least 25 to 50 at% of a rare earth element containing at least one or two or more elements and at least Ga. 50 to 75
1 to 4 and FIG. 5, the cold storage material using the rare earth elements R and Ga is an RGa ₂ compound,
RGa ₂ compound and RGa compound, RGa ₂ compound and RG
Since a ₃ compound mixed-tissue is produced, the magnetic transition point approximately becomes less longitudinal 10K of these compounds, since the presence of the specific heat peak in the vicinity of the magnetic transition point, specific heat in the following 10K is large, 10K There is an effect of improving the cold storage efficiency in the following.

In the regenerator according to the first embodiment, the content of the rare earth element is 33 to 50 at%.
Since a mixed structure of the Ga ₂ compound and the RGa compound is generated, it is possible to adjust the peak of the specific heat according to the ratio of the mixed structure.

Further, in the regenerator according to the first embodiment, since the rare earth element is Ho or Dy, a plurality of peaks are formed at 10K or less, the specific heat at 10K or less is increased, and the regenerative efficiency at 10K or less is improved. It has the effect of improving.

In the regenerator according to the first embodiment, since the rare earth element is Ho or Dy, a plurality of peaks are formed at 10 K or less, the specific heat at 10 K or less is increased, and the regenerative efficiency at 10 K or less is increased. In order to improve the refrigerating ability, it is important to improve the refrigerating capacity of regenerators of various refrigerators such as a GM (Gihod McMan) type, a pulse tube type, etc., as well as a Stirling type refrigerator as long as refrigeration around 10K is important. This has the effect of being applicable to various refrigerators.

(Second Embodiment) The regenerator according to the second embodiment is characterized in that a predetermined amount of at least one or more elements is added in addition to Ga which is an additive constituting the regenerator material of the first embodiment. Are the differences, and the following description will focus on the differences.

The regenerator material is at least Ce, Pr, N
25 to 50 at% of a rare earth element containing one or more elements such as d, Gd, Dy, Ho, and Er;
It is composed of a magnetic material comprising at least 50 to 75 at% of an additive containing Ga.

In the second embodiment, Dy of 33 at% or more can be adopted as the rare earth element, and the Ga-containing additive has a content of 67 at% or less.

The additives to be added are B, Al, I
n, Si, Ge, Sn, Au, Mg, Zn, Pd, P
t, Re, Cs, Ir, Fe, Mn, Cr, Cd, H
g, Os, and P are at least one element.

As the additive to be added in the second embodiment, B or Al can be adopted, and the content thereof is set to 5% or less of the additive.

In the regenerator according to the second embodiment having the above structure, the rare earth element is Ce,
One or two of Pr, Nd, Gd, Dy, Ho, Er, etc.
Because it contains more species, RGa ₂ compounds, RGa ₂ compound and RGa compound, for mixed tissue with RGa ₂ compound and RGa ₃ compound is produced, becomes less magnetic transition point approximately 10K before or after these compounds, Since a specific heat peak exists near the magnetic transition point, the specific heat around 10 K is large, and the cold storage efficiency at around 10 K is improved, and the refrigerating capacity around 10 K is increased.
There is an effect that the present invention can be applied to a refrigerator that generates refrigeration at around 0K.

Further, in the regenerator according to the second embodiment, the additive is B, Al, In, Si, Ge, Sn, Au, Mg,
Zn, Pd, Pt, Re, Cs, Ir, Fe, Mn, C
Since it contains an adduct of at least one element of r, Cd, Hg, Os, and P, by adding these elements, it becomes possible to broaden the specific heat peak and adjust the peak temperature. It has the effect of being able to do it.

Further, in the regenerator of the second embodiment, since the content of at least one element of the additive is 5 at% or less, the specific heat at 10 K or less is increased.
This has the effect of improving the cold storage efficiency below K.

In the regenerator according to the second embodiment, the rare earth element is Dy, and the additive is B or Al.
This has the effect of increasing the specific heat at 0K or less and improving the cold storage efficiency at 10K or less.

Hereinafter, embodiments of the present invention will be described more specifically. (First Embodiment) The regenerator of the first embodiment is filled with a regenerator material manufactured as follows.

5.42 g of holmium block (Ho)
(33.3 at% and gallium block (Ga) 4.58
g (66.7%) was placed in an arc melting furnace, and the arc melting furnace was evacuated and then replaced with argon gas.

Thereafter, arc storage is performed to produce a cold storage material, which is cut into 5 × 5 × 7 mm.

From the state diagrams shown in FIGS. 4 and 5, the cold storage material of the first embodiment manufactured as described above has a HoGa having a magnetic transition point Tn of 7.6K and a specific heat peak of 7K to 9K.
_Two compound tissues have been generated.

(Second Embodiment) The regenerator of the second embodiment is filled with a regenerator material manufactured as follows.

Dysprosium block (Dy) 5.38
2 g (33.3 at% and gallium block (Ga) 4.
618 g (66.7%) were placed in an arc melting furnace,
After vacuum suction of the arc melting furnace, the furnace is replaced with argon gas.

Thereafter, arc storage is performed to produce a regenerator material, which is cut into 5 × 5 × 7 mm.

The cold storage material of the second embodiment manufactured as described above shows that the magnetic transition point TN11K, the specific heat peaks 6.5K, 9K, and 11K are the same as those shown in FIGS.
The texture of the yGa ₂ compound has been generated.

In the first and second embodiments, the specific heat of the regenerator material was approximately 3 to 2 by adiabatic method using a Ge thermometer.
Measured at 5K. Here, the adiabatic method is to measure a temperature change ΔT when a Joule heat ΔQ is added to a sample (here, an ingot) under adiabatic conditions, and divide the Joule heat ΔQ by the temperature change ΔT to obtain a specific heat ΔC. How to FIG. 6 shows the specific heat measurement results.

As is clear from FIG. 6, the cold storage materials of the first embodiment and the second embodiment use the cold storage materials ErNi _0.8 Co _0.2 (conventional example 1) and Pb having the highest specific heat up to 10K or less. The specific heat at about 12K or less is larger than that of the cold storage material used (conventional example 2).

[0054] This cold accumulating material of the first and second embodiments, both Hoga ₂ compound and DyGa ₂ compound as shown in FIGS. 8 and 9, there is a magnetic transition point around 10K, magnetic It is considered that a high magnetic specific heat based on the transition was able to be expressed.

The regenerator material of the first and second embodiments has a large specific heat around 10K, improves the regenerative efficiency at around 10K, and increases the refrigerating capacity at around 10K. The effect that it becomes possible to apply to the refrigerator which generate | occur | produces.

(Conventional Example 1) The cold storage material of Conventional Example 1 is Pb1
The result of measuring the specific heat of the cold storage material of Conventional Example 1 in the same manner as in the first embodiment is shown by the dashed line in FIG.

As is clear from FIG. 6, the regenerator material of Conventional Example 1 has a specific heat of 12 K or less, which is lower than that of the first embodiment and the second embodiment.
It is smaller than the cold storage material of the embodiment. It is considered that this is because the specific heat of the lattice system based on the lattice vibration decreases significantly with the temperature drop and does not have the specific heat of the spin system.

(Conventional Example 2) The regenerative material of Conventional Example 2 is composed of 7.40 g (50 at%) of Er block and 2.0 block of Ni block.
8g (40 at%) and Co block 0.52 g (9a
t%) in the arc melting furnace.
This is the same as the embodiment.

Here, the cold storage material of Conventional Example 2 is ErNi
_0.8 Co _0.2 (magnetic transformation point 6 to 7K), and the result of measuring the specific heat in the same manner as in the first embodiment is shown by the thin broken line in FIG.

As is clear from FIG. 6, the regenerator material of Conventional Example 2 has a smaller specific heat at 7K to 9K than the regenerator material of the first embodiment.
The specific heat at K is smaller than that of the cold storage material of the second embodiment. It is considered that this is because the magnetic transformation point of ErNi _0.8 Co _0.2 exists at 6 to 7K, and the peak of specific heat exists at around 6 to 7K.

(Third Embodiment) The cold storage material of the regenerator of the third embodiment is 5.489 g of dysprosium block (Dy).
(33.3 at%) and gallium block (Ga) 4.
47 g (63.3%) and boron block (B) 0.0
37 (3.3%) is placed in an arc melting furnace to be arc melted, and aims at a Dy (Ga _0.95 B _0.05 ) ₂ structure.

(Fourth Embodiment) The cool storage material of the regenerator of the fourth embodiment is 5.459 g of dysprosium block (Dy).
(33.3 at%) and gallium block (Ga) 4.
45 g (63.3%) and aluminum block (Al) 0.
No. 091 (3.3%) is placed in an arc melting furnace to be melted by an arc, and realizes a Dy (Ga _0.95 Al _0.05 ) ₂ structure.

The method of manufacturing a regenerator material according to the third and fourth embodiments is the same as that of the first embodiment except that the boron block and the aluminum block are added to the dysprosium block and the gallium block, and are placed in the arc melting furnace. This is the same as in the first embodiment.

Here, the composition of the regenerator material of the third and fourth embodiments is the same as that of the DyGa ₂ structure except that 3.3% of Ga is replaced by B and Al. Things.

As shown in FIGS. 10 and 11, the specific heat measurement results were 0.3 J over 6 to 12 K, respectively.
/ Kcm ³ or more, and is a cold storage material having a high specific heat at around 10K.

The regenerator material of the third and fourth embodiments has a large specific heat at around 10K, improves the cold storage efficiency at around 10K, and increases the refrigerating capacity at around 10K. The effect that it becomes possible to apply to the refrigerator which generate | occur | produces.

The above-described embodiments are exemplarily described for explanation, and the present invention is not limited to these embodiments. Those skilled in the art will recognize from the claims, the detailed description of the invention, and the drawings. Modifications and additions are possible without departing from the technical idea of the present invention.

In the above embodiments and examples, an example in which a single regenerator is filled in a regenerator has been described as an example. However, the present invention is not limited to these, and is shown in FIG. A first cold storage material layer 11 made of the cold storage material according to the above-described embodiment and example including Ga,
ErNi _0.8 Co _{0.2 of} Conventional Example 2 having a magnetic transformation point of 6 to 7K
And a third cold storage material layer 1 made of ErAg having a magnetic transition point of 10 to 30K in the third conventional example.
Conventional example 1 having large specific heat at 3 and 10 to 30K
And a fourth regenerator material layer 14 made of Pb exhibiting a high specific heat at 15K to 40K in the regenerator 1, and having a high specific heat over a wide temperature range of 7, 8K to 40K as shown in FIG. It is possible to adopt a mode in which the refrigerating capacity at around 10K is increased and the refrigerating capacity at around 10K is improved, and the present invention can be applied to a refrigerator that generates refrigeration at around 10K.

[Brief description of the drawings]

FIG. 1 is a diagram showing a magnetic transformation point of an alloy present in a cold storage material according to the present invention.

FIG. 2 is a diagram showing a phase diagram of Ga-Dy.

FIG. 3 is a diagram showing a phase diagram of Ga-Dy.

FIG. 4 is a diagram showing a phase diagram of Ga-Ho.

FIG. 5 is a diagram showing a phase diagram of Ga-Ho.

FIG. 6 is a diagram showing specific heat characteristics at a low temperature of the first and second embodiments of the present invention, and conventional examples 1 and 2.

FIG. 7 is a principle explanatory view showing a Stirling refrigerator to which the regenerator of the first embodiment of the present invention is applied.

FIG. 8 is a diagram showing a specific heat characteristic at a low temperature of the regenerator according to the first embodiment of the present invention.

FIG. 9 is a diagram showing specific heat characteristics at a low temperature of a regenerator according to a second embodiment of the present invention.

FIG. 10 is a diagram showing specific heat characteristics of a regenerator according to a third embodiment of the present invention at a low temperature.

FIG. 11 is a diagram showing a specific heat characteristic at a low temperature of a regenerator according to a fourth embodiment of the present invention.

FIG. 12 is an explanatory diagram showing a regenerator according to another embodiment of the present invention.

FIG. 13 is a diagram showing specific heat characteristics at a low temperature of a regenerator according to another embodiment of the present invention.

[Explanation of symbols]

 1 regenerator 10 regenerator material

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-294034 (JP, A) JP-A 8-178443 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F25B 9/00

Claims (8)

(57) [Claims] 1. A regenerator filled with a regenerator material, wherein the regenerator material contains 25 to 50 at% rare earth element containing at least one or two or more elements, and at least 50 at% or more Ga. A regenerator characterized in that the regenerator is a magnetic material comprising 50 to 75 at% of an additive. 2. The method according to claim 1, wherein the rare earth element is Ce, Pr, Nd, Gd, Dy, H
A regenerator comprising one or more of o, Er and the like. 3. The method according to claim 2, wherein the additive is B, Al, In, Si, Ge, Sn, A.
u, Mg, Zn, Pd, Pt, Re, Cs, Ir, F
e, at least one of Mn, Cr, Cd, Hg, Os, and P
A regenerator comprising a kind of element. 4. The method according to claim 3, wherein the content of at least one element of the additive is 5 at.
% Or less. 5. The regenerator according to claim 2, wherein the content of the rare earth element is 25 to 33 at%. 6. The regenerator according to claim 2, wherein the content of the rare earth element is 33 to 50 at%. 7. The regenerator according to claim 5, wherein the rare earth element is Dy, and the additive is B or Al. 8. The regenerator according to claim 5, wherein the rare earth element is Ho or Dy.