JP2006339284A - Thermoelectric module - Google Patents

Thermoelectric module Download PDF

Info

Publication number
JP2006339284A
JP2006339284A JP2005160127A JP2005160127A JP2006339284A JP 2006339284 A JP2006339284 A JP 2006339284A JP 2005160127 A JP2005160127 A JP 2005160127A JP 2005160127 A JP2005160127 A JP 2005160127A JP 2006339284 A JP2006339284 A JP 2006339284A
Authority
JP
Japan
Prior art keywords
thermoelectric conversion
conversion element
electrode
powder
sintering
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP2005160127A
Other languages
Japanese (ja)
Other versions
JP4584035B2 (en
Inventor
Kazuo Ebisumori
一雄 戎森
Tetsuya Kamimura
上村　　哲也
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toyota Motor Corp
Aisin Corp
Original Assignee
Aisin Seiki Co Ltd
Toyota Motor Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Aisin Seiki Co Ltd, Toyota Motor Corp filed Critical Aisin Seiki Co Ltd
Priority to JP2005160127A priority Critical patent/JP4584035B2/en
Publication of JP2006339284A publication Critical patent/JP2006339284A/en
Application granted granted Critical
Publication of JP4584035B2 publication Critical patent/JP4584035B2/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Abstract

<P>PROBLEM TO BE SOLVED: To enable to avoid crack of a thermoelectric conversion element, improve junction capability between the thermoelectric conversion element and an electrode and improve thermoelectric conversion performance therebetween. <P>SOLUTION: The electrode joined to the thermoelectric conversion element has a configuration including a component of Ti<SB>X</SB>Cu<SB>1-X</SB>(x=0.2 to 0.43) and having a linear expansion coefficient of 12×10<SP>-6</SP>to 15×10<SP>-6</SP>[/K]. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

本発明は、熱電モジュールに関する。   The present invention relates to a thermoelectric module.

ゼーベック効果を利用した熱電変換素子は、熱エネルギーを電気エネルギーに変換することが可能である。この性質を利用し、産業・民生用プロセスや移動体から排出される排熱を有効な電力に変換することができるため、熱電変換素子は、環境問題に配慮した省エネルギー技術として注目されている。   A thermoelectric conversion element using the Seebeck effect can convert heat energy into electric energy. Because this property can be used to convert exhaust heat discharged from industrial and consumer processes and mobile objects into effective power, thermoelectric conversion elements are attracting attention as energy-saving technologies that take environmental issues into consideration.

熱電変換素子の性能は、性能指数ＺＴ＝α2σＴ／κ〔α：ゼーベック係数、σ：電気伝導度、κ：熱伝導度、Ｔ：測定温度〕で表すことができるが、高い性能指数を示す熱電変換素子としては従来から、ビスマス・テルル系材料、シリコン・ゲルマニウム系材料、鉛・テルル系材料などを用いた熱電変換素子が知られている。また、アルミニウムをドープした酸化亜鉛粉を成形、焼成してなる熱電変換素子も知られている（例えば、特許文献１参照）。 The performance of the thermoelectric conversion element can be expressed by a figure of merit ZT = α 2 σT / κ [α: Seebeck coefficient, σ: electrical conductivity, κ: thermal conductivity, T: measurement temperature]. Conventionally, thermoelectric conversion elements using bismuth / tellurium-based materials, silicon / germanium-based materials, lead / tellurium-based materials, and the like are known. A thermoelectric conversion element formed by molding and baking zinc oxide powder doped with aluminum is also known (see, for example, Patent Document 1).

さらに近年では、新規な熱電変換素子の材料としてクラスレート化合物が注目されている（例えば、非特許文献１参照）。   In recent years, clathrate compounds have attracted attention as materials for novel thermoelectric conversion elements (see, for example, Non-Patent Document 1).

上記のような熱電変換素子を用いた熱電モジュールは、熱電変換素子に温度差を与えたときに熱電変換し、熱から電流及び電圧を取り出せるように構成される。したがって、熱電変換素子と接合する電極（Ｃｕ，Ｎｉ等）を設ける必要があり、電極との接合には高温域でも耐え得るように銀ろう等のろう材（接合材料）が用いられている。   The thermoelectric module using the thermoelectric conversion element as described above is configured to perform thermoelectric conversion when a temperature difference is given to the thermoelectric conversion element, and to extract current and voltage from the heat. Therefore, it is necessary to provide an electrode (Cu, Ni, etc.) to be joined to the thermoelectric conversion element, and a brazing material (joining material) such as silver brazing is used for joining with the electrode so that it can withstand even in a high temperature range.

ところが、発電時の温度は約６００℃程度の高温域にまで及ぶため、ろう材成分やＣｕ，Ｎｉ等の電極成分、熱電変換素子成分は相互に拡散しやすく、熱電変換素子が溶解したり、あるいは電極／熱電変換素子の接合界面が剥離する、電極／熱電変換素子間に不純物相ができる等を招来するほか、構成要素間で線膨張係数（熱膨張率）が相互に大きく異なることに起因して熱電変換素子に割れ（破断）が発生しやすくなる傾向がある。このような場合には、熱電変換特性は低下し、電流が流れなくなる現象を招くことになる。   However, since the temperature during power generation extends to a high temperature range of about 600 ° C., the brazing filler metal component, the electrode component such as Cu, Ni, and the thermoelectric conversion element component easily diffuse to each other, and the thermoelectric conversion element dissolves, Otherwise, the interface between the electrode / thermoelectric conversion element is peeled off, an impurity phase is formed between the electrode / thermoelectric conversion element, etc., and the linear expansion coefficient (thermal expansion coefficient) differs greatly between the components. Thus, cracks (breaks) tend to occur in the thermoelectric conversion element. In such a case, the thermoelectric conversion characteristics are degraded, leading to a phenomenon in which current does not flow.

上記に関連して、熱電変換素子と電極との間で熱応力が発生して破断するのを防止するため、線膨張係数の異なる２種類の金属板を貼り合せて電極を作製し、電極の線膨張係数を熱電変換素子の線膨張係数に近づける技術が開示されている（例えば、特許文献２参照）。
特開２００２−１１８２９６号公報 特開２００４−６３５８５号公報 Proc. 21th Int. Conf. on Thermoelectrics, 2002, pp.77-80. In relation to the above, in order to prevent thermal stress between the thermoelectric conversion element and the electrode from breaking, two types of metal plates having different linear expansion coefficients are bonded to produce an electrode. A technique for making the linear expansion coefficient close to the linear expansion coefficient of the thermoelectric conversion element is disclosed (for example, see Patent Document 2).
JP 2002-118296 A JP 2004-63585 A Proc. 21th Int. Conf. On Thermoelectrics, 2002, pp.77-80.

しかし、板材では、厚み管理が細かくできないために厚みの影響を直に受け、厳密に線膨張係数を調整することは難しい。また、板材を貼り合せる構成では、電極が厚く電極特性が低下するばかりか、金属板の貼り合せは熱間圧延法、爆着法、鋳ぐるみ法によるものとされ、一般の銅電極に比べてコスト高になる。   However, since the thickness of the plate material cannot be finely controlled, it is directly affected by the thickness, and it is difficult to strictly adjust the linear expansion coefficient. In addition, in the configuration in which the plate material is bonded, not only the electrode is thick and the electrode characteristics are deteriorated, but the metal plate is bonded by the hot rolling method, the explosive deposition method, the cast-in method, and compared with a general copper electrode. High cost.

したがって、コストを維持しつつ、必ずしも電極及び熱電材料間の熱膨張差を低く保つことはできず、電極／熱電変換素子間での接合剥がれ、及び熱電変換素子の割れ（破断）の発生を効果的に解消することは困難である。特に４００℃以上の高温域では、熱電変換素子と電極との接合部付近で熱電変換素子の割れが生じやすい。   Therefore, while maintaining the cost, it is not always possible to keep the difference in thermal expansion between the electrode and the thermoelectric material low, and it is effective for the peeling of the junction between the electrode / thermoelectric conversion element and the generation (breaking) of the thermoelectric conversion element. It is difficult to eliminate it. In particular, in a high temperature range of 400 ° C. or higher, the thermoelectric conversion element is likely to crack near the junction between the thermoelectric conversion element and the electrode.

本発明は、上記に鑑みなされたものであり、熱電変換素子の割れ（破断）の発生が抑えられると共に、電極及び熱電変換素子間の接合性が良好で、高度の熱電変換特性を有する熱電モジュールを提供することを目的とし、該目的を達成することを課題とする。   The present invention has been made in view of the above, and is capable of suppressing the occurrence of cracking (breaking) of the thermoelectric conversion element, having good bonding between the electrode and the thermoelectric conversion element, and having high thermoelectric conversion characteristics. It is an object to provide this and to achieve the object.

本発明は、熱電変換素子を挟む電極を２種類の金属元素、特にチタン（Ｔｉ）及び銅（Ｃｕ）を所定の割合で含む組成とした構成が、電極と熱電変換素子との間の熱膨張差を小さくし、熱膨張に起因する接合剥がれや熱電変換素子の割れの発生防止に有効であり、また、この構成が高温での信頼性の確保に効果的であるとの知見を得、かかる知見に基づいて達成されたものである。   In the present invention, a structure in which an electrode sandwiching a thermoelectric conversion element has a composition containing two kinds of metal elements, particularly titanium (Ti) and copper (Cu) at a predetermined ratio, is a thermal expansion between the electrode and the thermoelectric conversion element. The difference is reduced, effective in preventing the occurrence of bond peeling and thermoelectric conversion element cracks due to thermal expansion, and the knowledge that this configuration is effective in ensuring reliability at high temperatures has been obtained. It was achieved based on knowledge.

前記目的を達成するために、本発明の熱電モジュールは、少なくとも一方の電極（好ましくは少なくとも高温側の電極）がＴｉxＣｕ1-x（ｘ＝０．２〜０．４３）の組成を含み、かつ線膨張係数が１２×１０-6〜１５×１０-6［／Ｋ］である一対の電極と、該一対の電極間に配置された熱電変換素子とで構成されたものである。 In order to achieve the above object, the thermoelectric module of the present invention includes a composition in which at least one electrode (preferably at least a high temperature side electrode) is Ti x Cu 1-x (x = 0.2 to 0.43). And a linear expansion coefficient of 12 × 10 −6 to 15 × 10 −6 [/ K] and a thermoelectric conversion element arranged between the pair of electrodes.

本発明の熱電モジュールにおいては、電極を、ＴｉxＣｕ1-x（ｘ＝０．２〜０．４３）を含む組成とし、その線膨張係数が１２×１０-6〜１５×１０-6［／Ｋ］の範囲内となるように構成することで、熱電変換素子との接合性が向上すると共に、熱電変換素子との間の熱膨張差が低減されるので、広範な温度領域（特に室温〜６００℃）にわたり、電極と熱電変換素子との間の接合強度を向上でき、熱電変換素子の割れ（破断）を解消することができる。また、接合性が向上し、熱電変換素子との間で隙間のない良好な接合界面を形成し得るので、熱電変換素子及び電極間の接合にろう材等の接合材が不要であり、接合強度をも確保することができる。 In the thermoelectric module of the present invention, the electrode has a composition containing Ti x Cu 1-x (x = 0.2 to 0.43), and its linear expansion coefficient is 12 × 10 −6 to 15 × 10 −6 [ / K], the bonding property with the thermoelectric conversion element is improved, and the difference in thermal expansion with the thermoelectric conversion element is reduced. ˜600 ° C.), the bonding strength between the electrode and the thermoelectric conversion element can be improved, and cracking (breaking) of the thermoelectric conversion element can be eliminated. In addition, since the bondability is improved and a good bonding interface without gaps can be formed between the thermoelectric conversion elements, a bonding material such as a brazing material is not required for bonding between the thermoelectric conversion elements and the electrodes, and the bonding strength Can also be secured.

本発明の熱電モジュールを構成する熱電変換素子は、クラスレート化合物を用いて好適に構成することができる。ＴｉxＣｕ1-x（ｘ＝０．２〜０．４３）の組成を含む電極の線膨張係数は、クラスレート化合物の線膨張係数に特に近く、高温域に達した場合でも熱膨張差を小さく保つことができ、電極と熱電変換素子との間の接合強度の向上、及び熱電変換素子の割れの発生防止に効果的である。 The thermoelectric conversion element which comprises the thermoelectric module of this invention can be comprised suitably using a clathrate compound. The linear expansion coefficient of the electrode including the composition of Ti x Cu 1-x (x = 0.2 to 0.43) is particularly close to the linear expansion coefficient of the clathrate compound, and even when reaching a high temperature range, the thermal expansion difference is It can be kept small, and it is effective for improving the bonding strength between the electrode and the thermoelectric conversion element and preventing cracking of the thermoelectric conversion element.

ＴｉxＣｕ1-x（ｘ＝０．２〜０．４３）の組成を含む電極は、Ｔｉ粉及びＣｕ粉の混合粉末を用いて成形した後、これを焼結することにより、又はＴｉ−Ｃｕ合金粉末を用いて成形した後、これを焼結することにより、好適に形成することができる。Ｔｉ粉やＣｕ粉、合金粉の粉末によると、成形が容易で取扱いやすく、また、粉末形態で用いることで、その一部が焼結の際に熱電変換素子の内部に入り込んで接合されるので、板状もしくはシート状等の物を用いた場合に比して、熱電変換素子との間の接合強度をより高めることができる。すなわち、上記のように熱膨張差を抑えつつ、接合強度を高め得るので、電極／熱電変換素子間での接合剥がれや熱電変換素子の割れの発生の回避に特に有効である。 An electrode including a composition of Ti x Cu 1-x (x = 0.2 to 0.43) is formed using a mixed powder of Ti powder and Cu powder, and then sintered, or Ti— After forming using Cu alloy powder, it can form suitably by sintering this. According to the powder of Ti powder, Cu powder and alloy powder, it is easy to mold and easy to handle, and when used in powder form, part of it enters the thermoelectric conversion element and is joined during sintering. Compared with the case of using a plate-like or sheet-like article, the bonding strength between the thermoelectric conversion elements can be further increased. That is, since the bonding strength can be increased while suppressing the difference in thermal expansion as described above, it is particularly effective for avoiding the peeling of the bonding between the electrodes / thermoelectric conversion elements and the occurrence of cracks in the thermoelectric conversion elements.

特に、Ｔｉ−Ｃｕ合金粉末を用いて成形、焼結する場合、用いる合金粉末の組成で電極の組成、特性が決まるので、組成が均一な電極の形成に有効であり、所望特性を有する熱電モジュールを安定的に作製することができると共に、高温下でも特性変化を生じ難い高い耐久性を確保することができる。   In particular, when forming and sintering using Ti—Cu alloy powder, the composition and characteristics of the electrode are determined by the composition of the alloy powder to be used. Therefore, the thermoelectric module is effective in forming an electrode having a uniform composition and has desired characteristics. Can be stably produced, and high durability that hardly changes the characteristics even at high temperatures can be ensured.

本発明によれば、熱電変換素子の割れ（破断）の発生が抑えられると共に、電極及び熱電変換素子間の接合性が良好で、高度の熱電変換特性を有する熱電モジュールを提供することができる。   ADVANTAGE OF THE INVENTION According to this invention, while the generation | occurrence | production of the crack (fracture) of a thermoelectric conversion element is suppressed, the joining property between an electrode and a thermoelectric conversion element is favorable, and the thermoelectric module which has a high thermoelectric conversion characteristic can be provided.

以下、本発明の熱電モジュールの実施形態を図１を参照して説明する。
以下に示す実施形態では、熱電変換素子にクラスレート化合物を用いる場合を中心に説明する。ここでは、電極と熱電変換素子との接合をろう材等の接合材を用いずに行なうようにしたものである。なお、本発明においては、本実施形態に何ら制限されるものではない。 Hereinafter, an embodiment of a thermoelectric module of the present invention will be described with reference to FIG.
In the embodiment described below, a case where a clathrate compound is used for the thermoelectric conversion element will be mainly described. Here, the electrode and the thermoelectric conversion element are joined without using a joining material such as a brazing material. Note that the present invention is not limited to this embodiment.

本実施形態は、Ｎ型熱電変換素子をなすクラスレート化合物としてＢａ8Ｇａ15Ｇｅ31を、Ｐ型熱電変換素子をなすクラスレート化合物としてＢａ8Ｇａ18Ｇｅ28を用い、Ｔｉ2Ｃｕ3からなる組成に構成された電極を設けて構成したものである。 This embodiment, the Ba 8 Ga 15 Ge 31 as clathrate compound forming the N-type thermoelectric conversion element, using the Ba 8 Ga 18 Ge 28 as clathrate compound forming the P-type thermoelectric conversion element, consisting of Ti 2 Cu 3 An electrode having a composition is provided.

図１に示すように、本実施形態における熱電モジュール１は、Ｂａ8Ｇａ15Ｇｅ31で構成されたＮ型熱電変換素子１０とＢａ8Ｇａ18Ｇｅ28で構成されたＰ型熱電変換素子２０とを備えており、Ｎ型熱電変換素子１０及びＰ型熱電変換素子２０は、この両者と接合する単一のTiCu共通極３０及びこれと対極をなすTiCu対向極１１，２１により狭持された構造に構成されている。また、Ｎ型熱電変換素子１０はTiCu対向極１１と、Ｐ型熱電変換素子２０はTiCu対向極２１と、それぞれ直に接合されている。そして、TiCu共通極３０側を加熱（heat）すると共に、TiCu対向極１１及び２１側を所定の温度が保たれるように冷却することにより、温度差が与えられたときに発電できるようになっている。 As shown in FIG. 1, the thermoelectric module 1 in this embodiment includes an N-type thermoelectric conversion element 10 made of Ba 8 Ga 15 Ge 31 and a P-type thermoelectric conversion element 20 made of Ba 8 Ga 18 Ge 28. The N-type thermoelectric conversion element 10 and the P-type thermoelectric conversion element 20 are sandwiched between a single TiCu common electrode 30 and a TiCu counter electrode 11 and 21 that are counter electrodes of the TiCu common electrode 30. It is configured. The N-type thermoelectric conversion element 10 and the P-type thermoelectric conversion element 20 are directly bonded to the TiCu counter electrode 11 and the TiCu counter electrode 21, respectively. Then, while heating the TiCu common electrode 30 side and cooling the TiCu counter electrode 11 and 21 side so that a predetermined temperature is maintained, it becomes possible to generate power when a temperature difference is given. ing.

TiCu共通極３０及びTiCu対向極１１，２１はいずれも、Ｔｉ2Ｃｕ3の組成が含まれるように、チタン（Ｔｉ）粉と銅（Ｃｕ）粉とを混合した混合粉末を用いて成形し、成形された成形体を更に焼成することにより形成された電極である。 Each of the TiCu common electrode 30 and the TiCu counter electrodes 11 and 21 is molded using a mixed powder obtained by mixing titanium (Ti) powder and copper (Cu) powder so that the composition of Ti 2 Cu 3 is included, This is an electrode formed by further firing the molded body.

混合粉末中のＴｉ粉の純度は９９．９９％であり、Ｃｕ粉の純度は９９．９９％である。純度としては、上記以外に９９．９％以上の範囲で適宜選択することが可能である。   The purity of the Ti powder in the mixed powder is 99.99%, and the purity of the Cu powder is 99.99%. The purity can be appropriately selected within the range of 99.9% or more in addition to the above.

本発明においては、電極は前記組成以外に、ＴｉxＣｕ1-x（ｘ＝０．２〜０．４３）を満足する組成で構成される。組成を前記範囲で構成することにより、電極をクラスレート化合物に近い線膨張係数に構成することができ、クラスレート化合物（ここでは、Ｎ型熱電変換素子１０又はＰ型熱電変換素子２０）との熱膨張差を低減することができる。これにより、クラスレート化合物の割れを解消し得ると共に、電極とクラスレート化合物との間の接合界面の剥離防止に有効である。 In the present invention, the electrode is composed of a composition satisfying Ti x Cu 1-x (x = 0.2 to 0.43) in addition to the above composition. By configuring the composition within the above range, the electrode can be configured to have a linear expansion coefficient close to that of the clathrate compound, and with the clathrate compound (here, the N-type thermoelectric conversion element 10 or the P-type thermoelectric conversion element 20). The difference in thermal expansion can be reduced. Thereby, cracking of the clathrate compound can be eliminated, and it is effective for preventing peeling of the bonding interface between the electrode and the clathrate compound.

ＴｉxＣｕ1-x（０．２≦ｘ≦０．４３）の組成のうち、０．２５≦ｘ≦０．４３が好ましく、０．４０≦ｘ≦０．４３がより好ましい。好ましい具体的な例は、Ｔｉ2Ｃｕ3（ｘ＝０．４０）である。 Of the composition of Ti x Cu 1-x (0.2 ≦ x ≦ 0.43), 0.25 ≦ x ≦ 0.43 is preferable, and 0.40 ≦ x ≦ 0.43 is more preferable. A preferred specific example is Ti 2 Cu 3 (x = 0.40).

Ｔｉ2Ｃｕ3の組成を有するTiCu共通極３０及びTiCu対向極１１，２１の線膨張係数は、１３×１０-6［／Ｋ］である。 The linear expansion coefficients of the TiCu common electrode 30 and the TiCu counter electrodes 11 and 21 having the composition of Ti 2 Cu 3 are 13 × 10 −6 [/ K].

本実施形態のTiCu共通極３０及びTiCu対向極１１，２１以外に、本発明においては、ＴｉxＣｕ1-x（ｘ＝０．２〜０．４３）の組成で構成された電極は、線膨張係数が１２×１０-6〜１５×１０-6［／Ｋ］の範囲に構成されたものである。線膨張係数が前記範囲内であると、クラスレート化合物の線膨張係数に近く、熱膨張によるクラスレート化合物の割れや接合界面の剥離を効果的に回避することができる。 In the present invention, in addition to the TiCu common electrode 30 and the TiCu counter electrodes 11 and 21 of the present embodiment, an electrode configured with a composition of Ti x Cu 1-x (x = 0.2 to 0.43) is a line. The expansion coefficient is configured in the range of 12 × 10 −6 to 15 × 10 −6 [/ K]. When the linear expansion coefficient is within the above range, it is close to the linear expansion coefficient of the clathrate compound, and cracking of the clathrate compound and peeling of the bonding interface due to thermal expansion can be effectively avoided.

なお、線膨張係数は、ＴＭＡ８１４０（理学電気（株）製）を用いて測定されるものである。   The linear expansion coefficient is measured using TMA8140 (manufactured by Rigaku Corporation).

TiCu共通極３０及びTiCu対向極１１，２１は、Ｔｉ2Ｃｕ3の組成となるようにＴｉ粉（線膨張係数8×10-6〜11×10-6［／Ｋ］）とＣｕ粉（線膨張係数17×10-6〜21×10-6［／Ｋ］）とを混合して混合粉末とし、この混合粉末を成形し、成形された成形体を更に焼成して形成されたものであり、その具体的な方法としては下記方法が挙げられる。また、成形と焼結とは別々に行なう以外に、成形すると共に焼結するようにすることもできる。 The TiCu common electrode 30 and the TiCu counter electrodes 11 and 21 are composed of Ti powder (linear expansion coefficient 8 × 10 −6 to 11 × 10 −6 [/ K]) and Cu powder (wire) so that the composition of Ti 2 Cu 3 is obtained. Expansion coefficient 17 × 10 −6 to 21 × 10 −6 [/ K]) is mixed to form a mixed powder, the mixed powder is molded, and the molded body is further fired. The specific method includes the following methods. In addition to molding and sintering separately, molding and sintering can be performed.

成形すると共に焼結する場合、加圧成形しながら焼結することで好適に作製できる。加圧成形しながら焼結（加圧焼結）する方法としては、ホットプレス焼結法、熱間等方圧加圧焼結法、放電プラズマ焼結法等のいずれの方法も用いることができる。中でも特に放電プラズマ焼結法が好ましい。   In the case of molding and sintering, it can be suitably produced by sintering while pressure molding. As a method for sintering while performing pressure molding (pressure sintering), any method such as a hot press sintering method, a hot isostatic pressing method, a discharge plasma sintering method, or the like can be used. . Of these, the discharge plasma sintering method is particularly preferable.

放電プラズマ焼結法においては、焼結温度は６００〜９００℃が好ましく、６５０〜８５０℃がより好ましく、焼結時間は１０〜９０分が好ましく、２０〜６０分がより好ましく、加圧時の圧力は２０〜５０ＭＰａが好ましく、２５〜４５ＭＰａがより好ましい。   In the spark plasma sintering method, the sintering temperature is preferably 600 to 900 ° C, more preferably 650 to 850 ° C, the sintering time is preferably 10 to 90 minutes, more preferably 20 to 60 minutes, The pressure is preferably 20 to 50 MPa, and more preferably 25 to 45 MPa.

例えば、焼結装置の所定形状に形成された焼結用室もしくは容器に熱電変換素子の粉末と上記の混合粉末とを積層状態にして加圧焼結する方法、あらかじめ成形されたＮ型，Ｐ型の熱電変換素子の表面に上記の混合粉末を接触させて加圧焼結する方法、等により好適に行なうことができる。   For example, a method of pressure sintering by laminating a powder of a thermoelectric conversion element and the above mixed powder in a sintering chamber or container formed in a predetermined shape of a sintering apparatus, pre-shaped N type, P The method can be suitably performed by a method in which the above mixed powder is brought into contact with the surface of a thermoelectric conversion element of a mold and subjected to pressure sintering.

上記の方法例のうち、前者では、クラスレート化合物を用いて熱電変換素子を構成する場合の該熱電変換素子の焼結処理を行なうと同時に、熱電変換素子に電極を接合形成することが可能であり、後者では、所望の形状（厚みやサイズなど）の熱電変換素子を選択した構成が可能であると共に、接合界面の隙間が少なく接合バラツキの小さい、高度の接合強度を確保することができる。   Among the above method examples, in the former, it is possible to perform the sintering process of the thermoelectric conversion element in the case where the thermoelectric conversion element is configured using the clathrate compound, and at the same time, the electrode can be bonded to the thermoelectric conversion element. In the latter, a configuration in which a thermoelectric conversion element having a desired shape (thickness, size, etc.) is selected is possible, and a high degree of bonding strength can be ensured with few gaps at the bonding interface and small bonding variation.

Ｔｉ粉及びＣｕ粉を用いる場合、各々の平均粒径としては、０．１〜１００μｍの範囲内であるのが好ましく、１〜５０μｍの範囲内であるのがより好ましい。平均粒径が前記範囲内であると、混合時の組成の均一化の点で有利である。   When using Ti powder and Cu powder, the average particle diameter is preferably in the range of 0.1 to 100 μm, and more preferably in the range of 1 to 50 μm. When the average particle size is within the above range, it is advantageous in terms of homogenizing the composition at the time of mixing.

電極（ここでは、TiCu共通極３０及びTiCu対向極１１，２１）は、Ｔｉ粉とＣｕ粉とを混合した混合粉末を用いる以外に、あらかじめ所望の組成でＴｉとＣｕとを合金化したＴｉ−Ｃｕ合金の粉末（Ｔｉ−Ｃｕ合金粉末）を用い、このＴｉ−Ｃｕ合金粉末を成形、焼成して形成するようにすることもできる。Ｔｉ粉及びＣｕ粉の混合によるよりも、Ｔｉ−Ｃｕ合金粉末を用いた場合が、より層中の組成を均一化でき、所望の特性の電極を安定的に形成できると共に、（特に高温域で）高い耐久性が得られる点で好ましい。   The electrode (here, TiCu common electrode 30 and TiCu counter electrode 11, 21) is a Ti— alloy obtained by alloying Ti and Cu with a desired composition in advance, in addition to using a mixed powder obtained by mixing Ti powder and Cu powder. A Cu alloy powder (Ti—Cu alloy powder) may be used, and this Ti—Cu alloy powder may be formed and fired. When Ti-Cu alloy powder is used rather than by mixing Ti powder and Cu powder, the composition in the layer can be made more uniform, and electrodes having desired characteristics can be stably formed (especially in the high temperature range). ) It is preferable in that high durability can be obtained.

Ｔｉ−Ｃｕ合金粉末を用いる場合、その平均粒径としては、０．１〜１００μｍの範囲内であるのが好ましく、１〜５０μｍの範囲内であるのがより好ましい。平均粒径が前記範囲内であると、焼成時の組成の均一化の点で有利である。ここでの平均粒径は、前記同様にして測定されるものである。   When Ti—Cu alloy powder is used, the average particle size is preferably in the range of 0.1 to 100 μm, and more preferably in the range of 1 to 50 μm. When the average particle size is within the above range, it is advantageous in terms of uniform composition during firing. Here, the average particle diameter is measured in the same manner as described above.

また、Ｔｉ粉及びＣｕ粉あるいはＴｉ−Ｃｕ合金粉末を用いる以外に、ＴｉxＣｕ1-x（ｘ＝０．２〜０．４３）の組成を含むＴｉ−Ｃｕ合金で構成された合金板や合金シート等の板状材料を用い、これを熱電変換素子（好ましくはクラスレート化合物）の表面に接合して電極とするようにしてもよい。 In addition to using Ti powder and Cu powder or Ti—Cu alloy powder, an alloy plate made of a Ti—Cu alloy containing a composition of Ti x Cu 1-x (x = 0.2 to 0.43) A plate-like material such as an alloy sheet may be used, and this may be joined to the surface of a thermoelectric conversion element (preferably a clathrate compound) to form an electrode.

電極（ここでは、TiCu共通極３０及びTiCu対向極１１，２１）の厚みは、０．１〜２ｍｍが好ましく、０．５〜１ｍｍがより好ましい。   The thickness of the electrodes (here, the TiCu common electrode 30 and the TiCu counter electrodes 11 and 21) is preferably 0.1 to 2 mm, and more preferably 0.5 to 1 mm.

熱電変換素子、好ましくは（より好ましくは粉状の）クラスレート化合物と、Ｔｉ粉及びＣｕ粉の混合粉末又はＴｉ−Ｃｕ合金粉末あるいはＴｉＣｕ合金板等（電極成分）とを接触させた状態で焼成して電極を形成する際、焼成により混合粉末等の電極材料と熱電変換素子（好ましくはクラスレート化合物）との接触界面で成分拡散現象が起こり、熱電変換素子成分及び電極成分が互いに拡散しながら接合して拡散層を形成し得る。この拡散層の形成により、熱電変換素子及び電極間の接合強度が高められる。本実施形態では、不図示であるが、TiCu共通極３０及びTiCu対向極１１，２１とＮ型熱電変換素子（Ｂａ8Ｇａ15Ｇｅ31）１０又はＰ型熱電変換素子（Ｂａ8Ｇａ18Ｇｅ28）２０との接合界面において拡散層が形成される。 Firing in a state where a thermoelectric conversion element, preferably a clathrate compound (preferably in powder form), and a mixed powder of Ti powder and Cu powder, Ti-Cu alloy powder, TiCu alloy plate or the like (electrode component) is in contact When the electrode is formed, a component diffusion phenomenon occurs at the contact interface between the electrode material such as mixed powder and the thermoelectric conversion element (preferably clathrate compound) by firing, and the thermoelectric conversion element component and the electrode component are diffused to each other. Bonding can form a diffusion layer. By forming this diffusion layer, the bonding strength between the thermoelectric conversion element and the electrode is increased. Although not shown in the present embodiment, the TiCu common electrode 30 and the TiCu counter electrodes 11 and 21 and the N-type thermoelectric conversion element (Ba 8 Ga 15 Ge 31 ) 10 or the P-type thermoelectric conversion element (Ba 8 Ga 18 Ge 28). ) A diffusion layer is formed at the bonding interface with 20.

この拡散層の厚みとしては、５０μｍ以下であるのが望ましく、５〜３０μｍがより好ましい。なお、拡散層の厚み（μｍ）はＥＰＭＡ−１６１０〔（株）島津製作所製〕により撮影した写真を用いて測定されるものである。   The thickness of the diffusion layer is desirably 50 μm or less, and more preferably 5 to 30 μm. The thickness (μm) of the diffusion layer is measured using a photograph taken with EPMA-1610 (manufactured by Shimadzu Corporation).

Ｎ型熱電変換素子１０及びＰ型熱電変換素子２０は、上記のＢａ8Ｇａ15Ｇｅ31、Ｂａ8Ｇａ18Ｇｅ28で構成する以外に、他のクラスレート化合物を用いて構成することができる。他のクラスレート化合物としては、例えば、一般式ＩＩ8（ＩＩＩ，ＩＶ）46：〔ＩＩ＝Ｂａ，Ｓｒ，アルカリ金属，アルカリ土類金属；ＩＩＩ＝Ｇａ，Ｓｉ，Ｓｎ，Ａｌ，遷移金属；ＩＶ＝Ｇｅ，Ｓｉ，Ｓｎ，遷移金属〕で表される立方晶系のクラスレート化合物が挙げられる。これらから、Ｎ型用、Ｐ型用に適宜選択して用いることができる。 The N-type thermoelectric conversion element 10 and the P-type thermoelectric conversion element 20 can be configured using other clathrate compounds in addition to the above-described Ba 8 Ga 15 Ge 31 and Ba 8 Ga 18 Ge 28 . Other clathrate compounds include, for example, the general formula II 8 (III, IV) 46 : [II = Ba, Sr, alkali metal, alkaline earth metal; III = Ga, Si, Sn, Al, transition metal; IV = Ge, Si, Sn, transition metal]. From these, it can be appropriately selected and used for N-type and P-type.

上記の中でも、Ｂａ8ＧａyＧｅ46-yで表される立方晶系のクラスレート化合物が好適であり、前記ｙは１４≦ｙ≦２２を満たす範囲が好ましい。具体的な化合物例として、Ｂａ8Ｇａ16Ｇｅ30、Ｂａ8Ｇａ15Ｓｉ31、Ｂａ8Ｇａ16Ｓｉ30、Ｂａ8Ｇａ18Ｓｉ28、Ｂａ8Ｇａ14Ｓｎ32、Ｂａ8Ｇａ15Ｓｎ31、Ｂａ8Ｇａ16Ｓｎ30、Ｂａ8Ａｌ16Ｓｉ30、Ｂａ8Ａｌ16Ｇｅ30、Ｓｒ8Ａｌ16Ｓｉ30、Ｓｒ8Ｇａ16Ｓｉ30、Ｓｒ8Ｇａ16Ｇｅ30等が挙げられる。 Among the above, a cubic clathrate compound represented by Ba 8 Ga y Ge 46-y is preferable, and y is preferably in a range satisfying 14 ≦ y ≦ 22. As specific compound examples, Ba 8 Ga 16 Ge 30 , Ba 8 Ga 15 Si 31 , Ba 8 Ga 16 Si 30 , Ba 8 Ga 18 Si 28 , Ba 8 Ga 14 Sn 32 , Ba 8 Ga 15 Sn 31 , Ba 8 Ga 16 Sn 30, Ba 8 Al 16 Si 30, Ba 8 Al 16 Ge 30, Sr 8 Al 16 Si 30, Sr 8 Ga 16 Si 30, Sr 8 Ga 16 Ge 30 and the like.

Ｎ型及びＰ型の各熱電変換素子の作製は、例えば、微粒子状に粉砕されたクラスレート化合物を（場合により別のクラスレート化合物を併用する場合は、微粒子状に粉砕された別のクラスレート化合物と共に有機溶剤中で超音波攪拌器等により攪拌、分散して分散液とした後の乾燥後）成形し、成形されたクラスレート化合物を焼結することによって行なうことができる。また、成形と焼結とは別々に行なう以外に、成形すると共に焼結するようにすることもできる。   The production of each of the N-type and P-type thermoelectric conversion elements can be achieved by, for example, using a clathrate compound pulverized into fine particles (if another clathrate compound is used in combination, another clathrate pulverized into fine particles It can be carried out by molding and sintering the molded clathrate compound after stirring and dispersing in an organic solvent together with the compound with an ultrasonic stirrer or the like to obtain a dispersion and then drying. In addition to molding and sintering separately, molding and sintering can be performed.

成形すると共に焼結する場合、加圧成形しながら焼結することで好適に作製できる。ここでの加圧焼結は、前記電極の作製において加圧焼結する方法と同様の方法を利用して行なうことができる。例えば、ホットプレス焼結法、熱間等方圧加圧焼結法、放電プラズマ焼結法などである。中でも、放電プラズマ焼結法が好まし。   In the case of molding and sintering, it can be suitably produced by sintering while pressure molding. The pressure sintering here can be performed using a method similar to the method of pressure sintering in the production of the electrode. For example, a hot press sintering method, a hot isostatic pressing sintering method, a discharge plasma sintering method, and the like. Of these, the spark plasma sintering method is preferred.

熱電変換素子の作製においては、放電プラズマ焼結法では、焼結温度は６００〜９００℃が好ましく、６５０〜８５０℃がより好ましく、焼結時間は１０〜９０分が好ましく、２０〜６０分がより好ましく、加圧時の圧力は２０〜５０ＭＰａが好ましく、２５〜４５ＭＰａがより好ましい。   In the production of the thermoelectric conversion element, in the discharge plasma sintering method, the sintering temperature is preferably 600 to 900 ° C, more preferably 650 to 850 ° C, and the sintering time is preferably 10 to 90 minutes, and preferably 20 to 60 minutes. More preferably, the pressure during pressurization is preferably 20 to 50 MPa, more preferably 25 to 45 MPa.

また、複数のクラスレート化合物により熱電変換素子を構成する場合には、クラスレート化合物の一つを粒子状に粉砕、焼結して多孔体とし、この多孔体の空隙に他のクラスレート化合物を含浸させて作製することができる。含浸は、例えば溶融状態のクラスレート化合物中に多孔体を浸す方法などで行なえる。   When a thermoelectric conversion element is composed of a plurality of clathrate compounds, one of the clathrate compounds is pulverized and sintered to form a porous body, and another clathrate compound is placed in the voids of the porous body. It can be produced by impregnation. Impregnation can be performed, for example, by a method of immersing the porous body in a molten clathrate compound.

本実施形態では、上記のように加熱、加圧による拡散接合を行なって熱電変換素子と電極（TiCu共通極３０又はTiCu対向極１１，２１）とを接合するようにし、接合材（銀ろう等のろう材など）が不要である態様を説明したが、目的等に応じて熱電変換素子及び電極間に接合材（例えば銀ろう等のろう材）を設けて接合するようにすることも可能である。   In this embodiment, diffusion bonding by heating and pressurization is performed as described above to bond the thermoelectric conversion element and the electrode (TiCu common electrode 30 or TiCu counter electrode 11, 21), and a bonding material (silver brazing etc.) However, it is also possible to provide a bonding material (for example, a brazing material such as silver brazing) between the thermoelectric conversion element and the electrode according to the purpose or the like. is there.

熱電モジュール１に対し、TiCu共通極３０の熱電変換素子が接合されていない側から加熱（heat）すると共に、TiCu対向極１１，２１の熱電変換素子が接合されていない側を冷却してTiCu共通極３０側との間に温度差ができるように所定の温度域に保ち、電気的に繋がれた回路内に電圧が発生した場合には負荷（電球）に電流が流れて点灯される。   The TiCu common electrode 30 is heated from the side where the thermoelectric conversion elements of the TiCu common electrode 30 are not joined, and the side of the TiCu counter electrodes 11 and 21 where the thermoelectric conversion elements are not joined is cooled to share TiCu. When a voltage is generated in a circuit that is electrically connected so as to create a temperature difference with the pole 30 side, a current flows through the load (light bulb) and is lit.

本実施形態では、一対のＰ型／Ｎ型からなる熱電変換素子で構成された熱電モジュールを中心に説明したが、TiCu対向極１１に更にＰ型を、TiCu対向極２１にＮ型を更に接続し、ＮI型とＰI型、ＰI型とＮII型、ＮII型とＰIII型のように順次交互に接続されたＮ型／Ｐ型／Ｎ型／Ｐ型の熱電モジュールや、Ｐ型／Ｎ型の熱電変換素子がさらに複数組接続して構成された熱電モジュールの場合についても同様である。 In the present embodiment, the thermoelectric module composed of a pair of P-type / N-type thermoelectric conversion elements has been mainly described. However, the P-type is further connected to the TiCu counter electrode 11, and the N-type is further connected to the TiCu counter electrode 21. N-type / P-type / N-type / P-type thermoelectric modules that are connected in turn, such as N I- type and P I- type, P I- type and N II- type, N II- type and P III- type, The same applies to a thermoelectric module in which a plurality of P-type / N-type thermoelectric conversion elements are connected.

以下、実施例によって本発明をより具体的に説明する。但し、本発明はこれらの実施例に限定されるものではない。   Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.

（実施例１〜３）
−クラスレート化合物の成形−
図２に示すように、試料を加圧するパンチ４２とダイス４３とで取り囲むように形成された試料室４６を有し、試料室４６内に収容された試料を二つのパンチ４２で加圧すると共に二つのパンチ４２の試料室形成側とは逆側にカーボンプレート４７を介して設けられた電極４８から直流パルス電流を流すことによって、試料室４６内の試料を焼結できる放電プラズマ焼結装置を準備した。 (Examples 1-3)
-Molding of clathrate compounds-
As shown in FIG. 2, it has a sample chamber 46 formed so as to be surrounded by a punch 42 for pressurizing a sample and a die 43, and the sample accommodated in the sample chamber 46 is pressurized by two punches 42 and two. A discharge plasma sintering apparatus capable of sintering a sample in the sample chamber 46 by flowing a direct current pulse current from an electrode 48 provided via a carbon plate 47 on the opposite side to the sample chamber forming side of the two punches 42 is prepared. did.

まず、上記の放電プラズマ焼結装置の試料室４６内に、図２に示すように試料４０として、Ｂａ8Ｇａ15Ｇｅ31の粉体（平均粒径〜７５μｍ；クラスレート化合物）１０ｇを収容し、０．０５ＭＰａのアルゴン雰囲気とした後、パンチ圧４０ＭＰａ、加熱温度８２０℃、加熱時間６０分間の焼結条件となるように直流電流をパルス状に流して焼結を行なって、φ２０×４．５ｍｍの焼結体を作製し、切断研磨により□４×厚み４ｍｍサイズのＢａ8Ｇａ15Ｇｅ31チップ（Ｎ型熱電変換素子）を成形した。そして、試料室４６からＢａ8Ｇａ15Ｇｅ31チップを取り出した。 First, 10 g of Ba 8 Ga 15 Ge 31 powder (average particle diameter: 75 μm; clathrate compound) is accommodated as a sample 40 as shown in FIG. 2 in the sample chamber 46 of the above discharge plasma sintering apparatus. , 0.05 MPa of argon atmosphere, sintering was performed by flowing a direct current in a pulsed manner so that the sintering conditions were a punch pressure of 40 MPa, a heating temperature of 820 ° C., and a heating time of 60 minutes. A 5 mm sintered body was produced, and a Ba 8 Ga 15 Ge 31 chip (N-type thermoelectric conversion element) having a size of 4 × 4 mm in thickness was formed by cutting and polishing. Then, the Ba 8 Ga 15 Ge 31 chip was taken out from the sample chamber 46.

続いて、試料室４６内に試料４０として、Ｂａ8Ｇａ18Ｇｅ28の粉体（平均粒径〜７５μｍ；クラスレート化合物）１０ｇを収容し、上記と同条件にて焼結を行なって、φ２０×４．５ｍｍの焼結体を作製し、切断研磨により□４×厚み４ｍｍサイズのＢａ8Ｇａ18Ｇｅ28チップ（Ｐ型熱電変換素子）を成形した。そして、試料室４６からＢａ8Ｇａ18Ｇｅ28チップを取り出した。 Subsequently, 10 g of Ba 8 Ga 18 Ge 28 powder (average particle diameter: 75 μm; clathrate compound) is accommodated in the sample chamber 46 as the sample 40, and sintered under the same conditions as described above. A sintered body of × 4.5 mm was prepared, and a Ba 8 Ga 18 Ge 28 chip (P-type thermoelectric conversion element) having a size of □ 4 × thickness 4 mm was formed by cutting and polishing. Then, a Ba 8 Ga 18 Ge 28 chip was taken out from the sample chamber 46.

−電極の成形−
次に、上記と同じ放電プラズマ焼結装置の試料室４６内に、試料４０として、チタン粉（チタン純度９９．９９％、平均粒径〜３０μｍ）と銅粉（銅純度９９．９９％、平均粒径〜３０μｍ）とを、Ｔｉ0.2Ｃｕ0.8（実施例１）、Ｔｉ0.25Ｃｕ0.75（実施例２）、又はＴｉ0.43Ｃｕ0.57（実施例３）の組成となるように、それぞれ混合したチタン／銅混合粉を収容し、０．０５ＭＰａのアルゴン雰囲気とした後、パンチ圧１０ＭＰａ、加熱温度８００℃、加熱時間３０分間の焼結条件となるように直流電流をパルス状に流して焼結を行なった。このようにして、幅４．５ｍｍ×長さ１０ｍｍ×厚み４ｍｍサイズの電極を成形した。 -Electrode molding-
Next, in the sample chamber 46 of the same discharge plasma sintering apparatus as described above, as a sample 40, titanium powder (titanium purity 99.99%, average particle size ˜30 μm) and copper powder (copper purity 99.99%, average) Particle diameters˜30 μm) with a composition of Ti 0.2 Cu 0.8 (Example 1), Ti 0.25 Cu 0.75 (Example 2), or Ti 0.43 Cu 0.57 (Example 3). After containing copper mixed powder and making an argon atmosphere of 0.05 MPa, sintering is performed by applying a direct current in pulses so that the sintering conditions are a punch pressure of 10 MPa, a heating temperature of 800 ° C., and a heating time of 30 minutes. It was. In this way, an electrode having a size of width 4.5 mm × length 10 mm × thickness 4 mm was formed.

−熱電モジュールの作製−
次に、図３に示すように、上記より得たＢａ8Ｇａ15Ｇｅ31チップ（Ｎ型熱電変換素子）１０Ａ，１０Ｂ及びＢａ8Ｇａ18Ｇｅ28チップ（Ｐ型熱電変換素子）２０Ａ，２０Ｂと、TiCu電極３１とを加熱炉５０内に入れ、図３に示す積層状態となるように配置した。この加熱炉５０は、サンプルを載置するための試料台５３と、試料台５３上のサンプルを加圧するための重り５４と、試料台５３に取付けられ、重り５４を上下方向に移動可能なように支持する固定治具５１，５２とで構成されている。加熱は、炉内のヒーターからの輻射熱により行なえるようになっている。 -Production of thermoelectric module-
Next, as shown in FIG. 3, the Ba 8 Ga 15 Ge 31 chips (N-type thermoelectric conversion elements) 10A and 10B and the Ba 8 Ga 18 Ge 28 chips (P-type thermoelectric conversion elements) 20A and 20B obtained from the above are used. The TiCu electrode 31 was placed in the heating furnace 50 and arranged so as to be in the laminated state shown in FIG. The heating furnace 50 is attached to the sample stage 53 for placing the sample, a weight 54 for pressurizing the sample on the sample stage 53, and the sample stage 53 so that the weight 54 can be moved in the vertical direction. And fixing jigs 51 and 52 to be supported. Heating can be performed by radiant heat from a heater in the furnace.

０．０５ＭＰａのアルゴン雰囲気とした後、加熱炉５０を起動し、圧力０．０１ＭＰａ、加熱温度７２０℃、加熱時間１０分間の条件にて、各チップと電極とを拡散接合して組付け、図４に示すように構成された本発明の熱電モジュールを作製した。   After setting the argon atmosphere to 0.05 MPa, the heating furnace 50 is started, and each chip and the electrode are assembled by diffusion bonding under the conditions of a pressure of 0.01 MPa, a heating temperature of 720 ° C., and a heating time of 10 minutes. A thermoelectric module of the present invention configured as shown in FIG.

（実施例４）
実施例１において、チタン粉と銅粉とを混合したチタン／銅混合粉を、これと同量のＴｉ2Ｃｕ3合金粉末（平均粒径〜４５μｍ）に代えたこと以外、実施例１と同様にして、本発明の熱電モジュールを作製した。 Example 4
In Example 1, the titanium / copper mixed powder obtained by mixing the titanium powder and the copper powder was replaced with the same amount of Ti 2 Cu 3 alloy powder (average particle diameter: 45 μm), as in Example 1. Thus, the thermoelectric module of the present invention was produced.

（比較例１〜３）
実施例１において、チタン粉と銅粉とを混合したチタン／銅混合粉を、これと同量のＣｕ粉（ｘ＝０；比較例１）、Ｔｉ0.5Ｃｕ0.5のチタン／銅混合粉（比較例２）、又はＴｉ粉（ｘ＝１；比較例３）に代えたこと以外、実施例１と同様にして、比較の熱電モジュールを作製した。 (Comparative Examples 1-3)
In Example 1, a titanium / copper mixed powder obtained by mixing titanium powder and copper powder was mixed with the same amount of Cu powder (x = 0; Comparative Example 1), Ti 0.5 Cu 0.5 titanium / copper mixed powder (comparison) A comparative thermoelectric module was produced in the same manner as in Example 1 except that it was replaced with Example 2) or Ti powder (x = 1; Comparative Example 3).

（評価）
各実施例及び比較例で作製した熱電モジュールについて、下記の評価、測定を行なった。測定及び評価の結果は下記表１に示す。 (Evaluation)
The following evaluations and measurements were performed on the thermoelectric modules produced in each example and comparative example. The results of measurement and evaluation are shown in Table 1 below.

−１．線膨張係数の測定−
各熱電モジュールを組み立てる前の電極単体の線膨張係数［／Ｋ］をＴＭＡ８１４０（理学電気（株）製）を用いて測定した。 -1. Measurement of linear expansion coefficient
The linear expansion coefficient [/ K] of the single electrode before assembling each thermoelectric module was measured using TMA8140 (manufactured by Rigaku Corporation).

−２．接合界面の評価−
各熱電モジュールについて、TiCu電極３１の各々とＮ型熱電変換素子１０Ａ，１０Ｂ及びＰ型熱電変換素子２０Ａ，２０Ｂとの接合界面の接合状態を、光学顕微鏡により、接合界面に存在する隙間の有無を観察して評価した。 -2. Evaluation of bonding interface
For each thermoelectric module, the bonding state of the bonding interface between each of the TiCu electrode 31 and the N-type thermoelectric conversion elements 10A and 10B and the P-type thermoelectric conversion elements 20A and 20B is checked by an optical microscope for the presence or absence of a gap present at the bonding interface. Observed and evaluated.

−３．クラスレート割れの評価−
各熱電モジュールを用いて、Ｃｕ電極の一方を加熱（６００℃）すると共に他方を冷却し、電極間に温度差を形成して一定の電流を流した後に、Ｎ型熱電変換素子１０Ａ，１０Ｂ及びＰ型熱電変換素子２０Ａ，２０Ｂの割れの発生を目視により観察した。 -3. Evaluation of clathrate cracking
Using each thermoelectric module, one of the Cu electrodes is heated (600 ° C.) and the other is cooled, a temperature difference is formed between the electrodes and a constant current is passed, and then the N-type thermoelectric conversion elements 10A, 10B and Generation | occurrence | production of the crack of P-type thermoelectric conversion element 20A, 20B was observed visually.

−４．電極特性の評価−
（１）電気抵抗率
各熱電モジュールに対して、交流四端子法によって温度を変化させたときの比抵抗［ｎΩｍ］を測定し、電気特性を評価する指標とした。 -4. Evaluation of electrode characteristics
(1) Electric resistivity For each thermoelectric module, the specific resistance [nΩm] when the temperature was changed by the AC four-terminal method was measured and used as an index for evaluating electric characteristics.

（２）熱伝導度
各熱電モジュールについて、レーザーフラッシュ法を用いた常法により熱伝導度を求め、電気特性を評価する指標とした。 (2) Thermal conductivity The thermal conductivity of each thermoelectric module was obtained by a conventional method using a laser flash method, and used as an index for evaluating the electrical characteristics.

Figure 2006339284
Figure 2006339284

前記表１に示すように、実施例では、クラスレート化合物で構成された熱電変換素子の割れ（破断）の発生がなく、ろう材等の接合材を用いずに、熱電変換素子との接合性が良好で電極特性に優れた電極を備えた熱電モジュールを得ることができた。すなわち、この熱電モジュールは、安定した熱電変換特性を発揮し得るものである。   As shown in Table 1, in the examples, there is no occurrence of cracking (breaking) of the thermoelectric conversion element composed of the clathrate compound, and the bonding property with the thermoelectric conversion element without using a bonding material such as a brazing material. And a thermoelectric module having an electrode with excellent electrode characteristics was obtained. That is, this thermoelectric module can exhibit stable thermoelectric conversion characteristics.

これに対し、比較の熱電モジュールでは、接合界面は良好であったものの、電極及び熱電変換素子間の熱膨張差が大きく、接合界面での剥離や熱電変換素子の割れを解消することはできず、電極特性も劣っていた。   On the other hand, in the comparative thermoelectric module, although the bonding interface was good, the thermal expansion difference between the electrode and the thermoelectric conversion element was large, and peeling at the bonding interface and cracking of the thermoelectric conversion element could not be resolved. The electrode characteristics were also inferior.

本発明の実施形態に係る熱電モジュールを示す概略断面図である。It is a schematic sectional drawing which shows the thermoelectric module which concerns on embodiment of this invention. 実施例で使用した放電プラズマ焼結装置を説明するための概略断面図である。It is a schematic sectional drawing for demonstrating the discharge plasma sintering apparatus used in the Example. 拡散接合を行なうための加熱炉の構成例を示す概略断面図である。It is a schematic sectional drawing which shows the structural example of the heating furnace for performing diffusion bonding. 実施例で作製した熱電モジュールの構成を示す概略断面図である。It is a schematic sectional drawing which shows the structure of the thermoelectric module produced in the Example.

符号の説明Explanation of symbols

１０，１０Ａ，１０Ｂ…Ｎ型熱電変換素子（クラスレート化合物）
１１，２１…TiCu対向極
２０，２０Ａ，２０Ｂ…Ｐ型熱電変換素子（クラスレート化合物）
３０…TiCu共通極
３１…TiCu電極 10, 10A, 10B ... N-type thermoelectric conversion element (clathrate compound)
11, 21 ... TiCu counter electrode 20, 20A, 20B ... P-type thermoelectric conversion element (clathrate compound)
30 ... TiCu common electrode 31 ... TiCu electrode

Claims (4)

一対の電極間に熱電変換素子が設けられた熱電モジュールにおいて、
前記電極の少なくとも一方が、ＴｉxＣｕ1-x（ｘ＝０．２〜０．４３）の組成を含むと共に、線膨張係数が１２×１０-6〜１５×１０-6［／Ｋ］である熱電モジュール。 In a thermoelectric module in which a thermoelectric conversion element is provided between a pair of electrodes,
At least one of the electrodes includes a composition of Ti x Cu 1-x (x = 0.2 to 0.43), and a linear expansion coefficient is 12 × 10 −6 to 15 × 10 −6 [/ K]. A thermoelectric module. 前記熱電変換素子がクラスレート化合物である請求項１に記載の熱電モジュール。   The thermoelectric module according to claim 1, wherein the thermoelectric conversion element is a clathrate compound. 前記電極は、Ｔｉ粉及びＣｕ粉の混合粉末を用いて成形、焼結してなる請求項１又は２に記載の熱電モジュール。   The thermoelectric module according to claim 1 or 2, wherein the electrode is formed and sintered using a mixed powder of Ti powder and Cu powder. 前記電極は、Ｔｉ−Ｃｕ合金粉末を用いて成形、焼結してなる請求項１又は２に記載の熱電モジュール。   The thermoelectric module according to claim 1, wherein the electrode is formed and sintered using a Ti—Cu alloy powder.
JP2005160127A 2005-05-31 2005-05-31 Thermoelectric module Expired - Fee Related JP4584035B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2005160127A JP4584035B2 (en) 2005-05-31 2005-05-31 Thermoelectric module

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2005160127A JP4584035B2 (en) 2005-05-31 2005-05-31 Thermoelectric module

Publications (2)

Publication Number Publication Date
JP2006339284A true JP2006339284A (en) 2006-12-14
JP4584035B2 JP4584035B2 (en) 2010-11-17

Family

ID=37559608

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2005160127A Expired - Fee Related JP4584035B2 (en) 2005-05-31 2005-05-31 Thermoelectric module

Country Status (1)

Country Link
JP (1) JP4584035B2 (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1970972A1 (en) * 2007-03-15 2008-09-17 Ibiden Co., Ltd. Manufacturing method of thermoelectric converter
JP2010212579A (en) * 2009-03-12 2010-09-24 Atsumi Tec:Kk Method for producing thermoelectric conversion element
KR20120043279A (en) * 2010-10-26 2012-05-04 에스케이이노베이션 주식회사 Thermoelectric generation vehicle, tegv
WO2017105011A1 (en) * 2015-12-15 2017-06-22 주식회사 엘지화학 Metal paste and thermoelectric module
KR20170071405A (en) * 2015-12-15 2017-06-23 주식회사 엘지화학 Metal paste and thermoelectric module
JP2017162861A (en) * 2016-03-07 2017-09-14 古河機械金属株式会社 Method for manufacturing thermoelectric conversion material
JP2019165215A (en) * 2018-03-16 2019-09-26 三菱マテリアル株式会社 Thermoelectric conversion element

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109930024B (en) * 2019-04-02 2021-01-12 东北大学 High-strength and high-toughness copper-titanium alloy and preparation method thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06181341A (en) * 1992-12-11 1994-06-28 Tokin Corp Thermoelectric conversion module, thermoelectric cooling device and refrigerator
JP2002118296A (en) * 2000-10-05 2002-04-19 Unitika Ltd N-type thermoelectric conversion element for high temperature having high electric conductivity, and thermoelectric conversion module using it
JP2003234516A (en) * 2002-02-12 2003-08-22 Komatsu Ltd Thermoelectric module
JP2004063585A (en) * 2002-07-25 2004-02-26 Toshiba Corp Electrode material for thermoelectric element and thermoelectric element using same
JP2006319210A (en) * 2005-05-13 2006-11-24 Toyota Motor Corp Manufacturing method of thermoelectric conversion element

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06181341A (en) * 1992-12-11 1994-06-28 Tokin Corp Thermoelectric conversion module, thermoelectric cooling device and refrigerator
JP2002118296A (en) * 2000-10-05 2002-04-19 Unitika Ltd N-type thermoelectric conversion element for high temperature having high electric conductivity, and thermoelectric conversion module using it
JP2003234516A (en) * 2002-02-12 2003-08-22 Komatsu Ltd Thermoelectric module
JP2004063585A (en) * 2002-07-25 2004-02-26 Toshiba Corp Electrode material for thermoelectric element and thermoelectric element using same
JP2006319210A (en) * 2005-05-13 2006-11-24 Toyota Motor Corp Manufacturing method of thermoelectric conversion element

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1970972A1 (en) * 2007-03-15 2008-09-17 Ibiden Co., Ltd. Manufacturing method of thermoelectric converter
JP2010212579A (en) * 2009-03-12 2010-09-24 Atsumi Tec:Kk Method for producing thermoelectric conversion element
CN102422448A (en) * 2009-03-12 2012-04-18 株式会社渥美精机 Method of producing thermoelectric conversion device
KR20120043279A (en) * 2010-10-26 2012-05-04 에스케이이노베이션 주식회사 Thermoelectric generation vehicle, tegv
KR101707816B1 (en) * 2010-10-26 2017-02-20 에스케이이노베이션 주식회사 Thermoelectric Generation Vehicle, TEGV
KR102101474B1 (en) * 2015-12-15 2020-04-16 주식회사 엘지화학 Metal paste and thermoelectric module
KR20170071405A (en) * 2015-12-15 2017-06-23 주식회사 엘지화학 Metal paste and thermoelectric module
US10622533B2 (en) 2015-12-15 2020-04-14 Lg Chem, Ltd. Metal paste and thermoelectric module
WO2017105011A1 (en) * 2015-12-15 2017-06-22 주식회사 엘지화학 Metal paste and thermoelectric module
US10998482B2 (en) 2015-12-15 2021-05-04 Lg Chem, Ltd. Metal paste and thermoelectric module
JP2017162861A (en) * 2016-03-07 2017-09-14 古河機械金属株式会社 Method for manufacturing thermoelectric conversion material
WO2017154629A1 (en) * 2016-03-07 2017-09-14 古河機械金属株式会社 Method for producing thermoelectric conversion material
EP3428983A4 (en) * 2016-03-07 2019-10-30 Furukawa Co., Ltd. Method for producing thermoelectric conversion material
US10790431B2 (en) 2016-03-07 2020-09-29 Furukawa Co., Ltd. Method of manufacturing thermoelectric conversion material
JP2019165215A (en) * 2018-03-16 2019-09-26 三菱マテリアル株式会社 Thermoelectric conversion element
JP7242999B2 (en) 2018-03-16 2023-03-22 三菱マテリアル株式会社 Thermoelectric conversion element

Also Published As

Publication number Publication date
JP4584035B2 (en) 2010-11-17

Similar Documents

Publication Publication Date Title
JP4584035B2 (en) Thermoelectric module
EP3352233B1 (en) Thermoelectric conversion module and thermoelectric conversion device
JP6249382B2 (en) Thermoelectric conversion element and thermoelectric conversion module
JP6222666B2 (en) Mg-Si-based thermoelectric conversion material and manufacturing method thereof, sintered body for thermoelectric conversion, thermoelectric conversion element, and thermoelectric conversion module
TWI505522B (en) Method for manufacturing thermoelectric conversion module
JP2006319210A (en) Manufacturing method of thermoelectric conversion element
KR20140050390A (en) Thermoelectric module, thermoelectric device comprising the same, and process for preparing the thermoelectric element
WO2010111462A2 (en) Thermoelectric device, electrode materials and method for fabricating thereof
JP2009117792A (en) Thermoelectric conversion module and process for producing the same
JP2013191838A (en) Thermoelectric conversion module and manufacturing method of the same
JP4584034B2 (en) Thermoelectric module
JP2021044574A (en) Method for producing magnesium-based thermoelectric conversion material
US20230157174A1 (en) Thermoelectric conversion module
KR101801367B1 (en) Method of manufacturing thermoelectric element
JP2008192694A (en) Thermoelectric conversion module, and power generator and cooler employing the same
CN106159077B (en) Bismuth telluride-based thermoelectric power generation element and preparation method thereof
JP5686417B2 (en) Thermoelectric conversion module manufacturing method and thermoelectric conversion module
WO2013047474A1 (en) Sintered body, sintered body for thermoelectric conversion element, thermoelectric conversion element, and thermoelectric conversion module
JP2007294689A (en) Thermoelectric conversion element
JP4643371B2 (en) Thermoelectric module
JP2004311819A (en) Thermoelectric conversion module
JPH09172204A (en) Thermoelectric conversion apparatus and thermoelectric its manufacture
JP6809852B2 (en) Thermoelectric conversion element and thermoelectric conversion module
JP2010016132A (en) Thermoelectric conversion module and method of producing the same
JP2008034721A (en) Thermoelectric power generation element, and its manufacturing method

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20080123

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20100603

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20100608

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20100809

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20100824

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20100901

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20130910

Year of fee payment: 3

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

LAPS Cancellation because of no payment of annual fees