JPH0589946A - Electric heating body - Google Patents
Electric heating bodyInfo
- Publication number
- JPH0589946A JPH0589946A JP24906691A JP24906691A JPH0589946A JP H0589946 A JPH0589946 A JP H0589946A JP 24906691 A JP24906691 A JP 24906691A JP 24906691 A JP24906691 A JP 24906691A JP H0589946 A JPH0589946 A JP H0589946A
- Authority
- JP
- Japan
- Prior art keywords
- terminal portion
- electric heating
- heating element
- protective layer
- layer
- 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
Links
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、熱処理炉等に使用され
る電気発熱体に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric heating element used in a heat treatment furnace or the like.
【０００２】[0002]
【従来の技術と発明が解決しようとする課題】従来、酸
素存在下で加熱する熱処理炉においては、一般に、加熱
体として、二珪化モリブデン（ＭｏＳｉ2）からなる電
気発熱体を使用している。そして、この発熱体は、一般
に、Ｕ字型あるいはＷ字型の発熱部と、この発熱部の両
端に一体的に設けた端子部とからなり、端子部を炉壁に
設けた開口に断熱材を介して取り付けるものである。2. Description of the Related Art Conventionally, in a heat treatment furnace for heating in the presence of oxygen, an electric heating element made of molybdenum disilicide (MoSi 2 ) is generally used as a heating element. The heating element is generally composed of a U-shaped or W-shaped heating portion and terminal portions integrally provided at both ends of the heating portion. The terminal portion is provided with an insulating material in an opening provided in the furnace wall. It is attached via.
【０００３】また、この電気発熱体は、主として二珪化
モリブデン粉末を、粉末冶金法で製作され、使用時の発
熱により発熱部が高温となると、その成分であるＳｉが
Ｏ2と結合し、ＳｉＯ2（石英ガラス）が発熱部の表面に
形成され、これが保護層となり、発熱体の劣化、損傷を
防止するものである。This electric heating element is mainly made of molybdenum disilicide powder by the powder metallurgy method. When the heat-generating part becomes high temperature due to heat generation during use, Si as a component thereof is combined with O 2 to form SiO 2. 2 (quartz glass) is formed on the surface of the heat generating portion, and this serves as a protective layer to prevent deterioration and damage of the heat generating element.
【０００４】しかしながら、１０〜３０日連続して使用
すると、端子部にクラックが生じ、やがて、クラック部
で破断するという事故が生じ、寿命が短いという課題を
有していた。However, when it is continuously used for 10 to 30 days, a crack occurs in the terminal portion, and eventually an accident of breaking at the crack portion occurs, and there is a problem that the life is short.
【０００５】そこで、本発明者らは、前記事故について
種々検討した結果、前記クラックは炉内温度（約１４０
０℃以上）より低温の約８００℃〜９００℃の端子部で
発生することが判明した。また、その原因については、
電気発熱体は前述のように粉末冶金法で製作されるた
め、気孔質であり、この気孔内に侵入したＯ2がＳｉと
結合するが、温度が低いためガラス化されず、気孔内で
成長し、やがてクラックを生じさせるものであると推測
される。したがって、本発明は、端子部に予め保護層を
形成して前記課題を解決することのできる電気発熱体を
提供することを目的とする。Therefore, as a result of various studies on the accident, the present inventors found that the cracks were formed in the furnace temperature (about 140 ° C.).
It was found that it occurs in the terminal portion at a temperature of about 800 ° C to 900 ° C that is lower than 0 ° C). Also, regarding the cause,
Since the electric heating element is manufactured by the powder metallurgy method as described above, it has porosity, and O 2 that has penetrated into the pores combines with Si, but is not vitrified due to the low temperature and grows in the pores. However, it is speculated that it will eventually cause cracks. Therefore, it is an object of the present invention to provide an electric heating element that can solve the above problems by forming a protective layer on the terminal portion in advance.
【０００６】[0006]
【課題を解決するための手段】本発明は、前記目的を達
成するために、二珪化モリブデンからなる電気発熱体の
端子部表面に、Ｓｉ系保護層を予め形成したものであ
る。前記保護層はＳｉＯ2単体で構成しても良く、ま
た、高融点の他の酸化物と組み合わせて構成してもよ
い。後者の代表的なものとしては、３Ａｌ2Ｏ3・２Ｓｉ
Ｏ2、ＺｒＯ2・ＳｉＯ4等Ｓｉ系酸化物があげられる。In order to achieve the above object, the present invention has a Si-based protective layer formed in advance on the surface of a terminal portion of an electric heating element made of molybdenum disilicide. The protective layer may be composed of a simple substance of SiO 2 or may be composed in combination with another oxide having a high melting point. A typical example of the latter is 3Al 2 O 3 .2Si.
Examples thereof include Si-based oxides such as O 2 and ZrO 2 · SiO 4 .
【０００７】[0007]
【実施例】つぎに、本発明の実施例を図面にしたがって
説明する。図において、１は二珪化モリブデンからなる
電気発熱体で、Ｕ字形の発熱部２と、発熱部２の両端に
一体になった端子部３とからなる、従来公知のものであ
る。Embodiments of the present invention will now be described with reference to the drawings. In the figure, reference numeral 1 denotes an electric heating element made of molybdenum disilicide, which is conventionally known and includes a U-shaped heating portion 2 and terminal portions 3 integrated at both ends of the heating portion 2.
【０００８】本発明においては、前記端子部３の表面に
Ｓｉ系保護層４を設けたものである。この保護層４の形
成方法としては、下記するプラズマ溶射法とＣＶＤ法と
が最適である。In the present invention, the Si-based protective layer 4 is provided on the surface of the terminal portion 3. As a method of forming the protective layer 4, the plasma spraying method and the CVD method described below are most suitable.
【０００９】ところで、プラズマ溶射においては、Ｓｉ
Ｏ2はガス化し溶射ができないため、昇華温度がより高
いＡｌ2Ｏ3あるいはＺｒＯ2の介在のもとで溶射し、端
子部３の表面に、０．５〜１００μの厚さの３Ａｌ2Ｏ3
・２ＳｉＯ2あるいはＺｒＳｉＯ4等のＳｉ系保護層４を
形成する。また、ＣＶＤ法では、ＳｉＯ2単体での緻密
な保護層の形成が可能であり、０．０１〜５０μ厚のＳ
ｉＯ2の保護層４を端子部３の表面に形成する。By the way, in plasma spraying, Si
Since O 2 is gasified and cannot be sprayed, it is sprayed under the interposition of Al 2 O 3 or ZrO 2 having a higher sublimation temperature, and the surface of the terminal portion 3 is coated with 3Al 2 O having a thickness of 0.5 to 100 μ. 3
Form a Si-based protective layer 4 such as 2SiO 2 or ZrSiO 4 . Further, in the CVD method, it is possible to form a dense protective layer by using SiO 2 alone, and an S of 0.01 to 50 μm is formed.
The protective layer 4 of iO 2 is formed on the surface of the terminal portion 3.
【００１０】そして、前記のようにして、端子部３に保
護層４を形成した電気発熱体１を、雰囲気を大気とした
焼成炉で使用したところ、いずれの方法で保護層４を形
成したものであっても、１２ケ月連続して使用しても何
ら異常が認められなかった。Then, when the electric heating element 1 having the protective layer 4 formed on the terminal portion 3 as described above is used in a firing furnace in which the atmosphere is the atmosphere, the protective layer 4 is formed by any method. However, no abnormality was observed even after continuous use for 12 months.
【００１１】これは、保護層４が電気発熱体の一成分で
あるＳｉと同系のＳｉ系であるため、端子部３との密着
性がよく、かつ、プラズマ溶射においては、ガラス質
（ＳｉＯ2）が、ＣＶＤ法によれば緻密なＳｉＯ2層が端
子部３の表面に形成され、これらの保護層４により、端
子部３内への酸素の侵入を防止し、端子部３の気孔内部
でガラス化されないＳｉＯ2が形成されないためである
と考えられる。Since the protective layer 4 is made of Si, which is similar to Si, which is one component of the electric heating element, it has good adhesion to the terminal portion 3 and, in plasma spraying, is glassy (SiO 2 ), A dense SiO 2 layer is formed on the surface of the terminal portion 3 by the CVD method, and the protective layer 4 prevents oxygen from entering the terminal portion 3 and prevents the oxygen from entering the inside of the pores of the terminal portion 3. It is considered that this is because SiO 2 which is not vitrified is not formed.
【００１２】[0012]
【発明の効果】以上の説明で明らかなように、本発明に
よれば、二珪化モリブデン（ＭｏＳｉ2）からなる電気
発熱体において、前記発熱体の端子部表面にＳｉ系保護
層を形成するという簡単な手段を端子部に施すことによ
り、電気発熱体を長期に亙って使用することができ、生
産性を大巾に向上することができる。As is apparent from the above description, according to the present invention, in the electric heating element made of molybdenum disilicide (MoSi 2 ), the Si-based protective layer is formed on the surface of the terminal portion of the heating element. By applying a simple means to the terminal portion, the electric heating element can be used for a long period of time, and the productivity can be greatly improved.
【図１】 本発明にかかる電気発熱体の斜視図。FIG. 1 is a perspective view of an electric heating element according to the present invention.
１…電気発熱体、２…発熱部、３…端子部、４…保護
層。DESCRIPTION OF SYMBOLS 1 ... Electric heating element, 2 ... Heating part, 3 ... Terminal part, 4 ... Protective layer.
Claims (1)
おいて、前記発熱体の端子部表面にＳｉ系保護層を形成
したことを特徴とする電気発熱体。1. An electric heating element made of molybdenum disilicide, wherein an Si-based protective layer is formed on a surface of a terminal portion of the heating element.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3249066A JPH0785435B2 (en) | 1991-09-27 | 1991-09-27 | Electric heating element |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3249066A JPH0785435B2 (en) | 1991-09-27 | 1991-09-27 | Electric heating element |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0589946A true JPH0589946A (en) | 1993-04-09 |
| JPH0785435B2 JPH0785435B2 (en) | 1995-09-13 |
Family
ID=17187502
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3249066A Expired - Lifetime JPH0785435B2 (en) | 1991-09-27 | 1991-09-27 | Electric heating element |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0785435B2 (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0886458A2 (en) * | 1997-05-23 | 1998-12-23 | Kabushiki Kaisha Riken | Molybdenum disilicide heating element and its production method |
| WO2004045026A2 (en) | 2002-11-07 | 2004-05-27 | Advanced Lighting Technologies, Inc. | Oxidation-protected metallic foil and methods |
| US7164103B2 (en) * | 2002-04-05 | 2007-01-16 | Sandvik Intellectual Property Aktiebolag | Electrical heating resistance element |
| US8053710B2 (en) * | 2002-04-05 | 2011-11-08 | Sandvik Intellectual Property Aktiebolag | Method of making a heating element of the molybdenum silicide type and a heating element |
| US8277274B2 (en) | 2002-11-07 | 2012-10-02 | Advanced Lighting Technologies, Inc. | Apparatus and methods for use of refractory abhesives in protection of metallic foils and leads |
| JP2016115620A (en) * | 2014-12-17 | 2016-06-23 | 日本電気硝子株式会社 | Exothermic body and manufacturing method of the same |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5748490A (en) * | 1980-08-29 | 1982-03-19 | Tokyo Electric Power Co | Safety device for collision |
-
1991
- 1991-09-27 JP JP3249066A patent/JPH0785435B2/en not_active Expired - Lifetime
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5748490A (en) * | 1980-08-29 | 1982-03-19 | Tokyo Electric Power Co | Safety device for collision |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0886458A2 (en) * | 1997-05-23 | 1998-12-23 | Kabushiki Kaisha Riken | Molybdenum disilicide heating element and its production method |
| EP0886458A3 (en) * | 1997-05-23 | 1999-10-20 | Kabushiki Kaisha Riken | Molybdenum disilicide heating element and its production method |
| US7164103B2 (en) * | 2002-04-05 | 2007-01-16 | Sandvik Intellectual Property Aktiebolag | Electrical heating resistance element |
| US8053710B2 (en) * | 2002-04-05 | 2011-11-08 | Sandvik Intellectual Property Aktiebolag | Method of making a heating element of the molybdenum silicide type and a heating element |
| WO2004045026A2 (en) | 2002-11-07 | 2004-05-27 | Advanced Lighting Technologies, Inc. | Oxidation-protected metallic foil and methods |
| EP1563524A2 (en) * | 2002-11-07 | 2005-08-17 | Advanced Lighting Technologies, Inc. | Oxidation-protected metallic foil in methods |
| EP1563524A4 (en) * | 2002-11-07 | 2008-12-10 | Advanced Lighting Tech Inc | Oxidation-protected metallic foil in methods |
| US8264147B2 (en) | 2002-11-07 | 2012-09-11 | Advanced Lighting Technologies, Inc. | Oxidation-protected metallic foil and methods |
| US8277274B2 (en) | 2002-11-07 | 2012-10-02 | Advanced Lighting Technologies, Inc. | Apparatus and methods for use of refractory abhesives in protection of metallic foils and leads |
| JP2016115620A (en) * | 2014-12-17 | 2016-06-23 | 日本電気硝子株式会社 | Exothermic body and manufacturing method of the same |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0785435B2 (en) | 1995-09-13 |
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