JPS5911172B2 - thermionic emission cathode - Google Patents
thermionic emission cathodeInfo
- Publication number
- JPS5911172B2 JPS5911172B2 JP51015224A JP1522476A JPS5911172B2 JP S5911172 B2 JPS5911172 B2 JP S5911172B2 JP 51015224 A JP51015224 A JP 51015224A JP 1522476 A JP1522476 A JP 1522476A JP S5911172 B2 JPS5911172 B2 JP S5911172B2
- Authority
- JP
- Japan
- Prior art keywords
- hexaboride
- barrier material
- reaction barrier
- thermionic emission
- cathode
- 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.)
- Expired
Links
Landscapes
- Solid Thermionic Cathode (AREA)
Description
【発明の詳細な説明】
本発明は、少ない消費電力で長時間安定に作動する六硼
化物系熱電子放射陰極に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hexaboride-based thermionic emission cathode that operates stably for a long time with low power consumption.
六硼化ランタン（ＬａＢ６λ初めとした六硼化物は仕事
関数が小さく、従来使用されているタングステン、およ
び酸化物系熱電子放射材に代る材料として注目されてい
るが、これらの材料は高温に於で大部分の材料と反応す
るために、加熱時の支持が困難である。Hexaborides such as lanthanum hexaboride (LaB6λ) have a small work function and are attracting attention as materials to replace conventionally used tungsten and oxide-based thermionic materials, but these materials cannot be used at high temperatures. It is difficult to support during heating because it reacts with most materials in the atmosphere.
これらの欠点を解決するためいろいろの提案がある。Various proposals have been made to solve these shortcomings.
例えば、（１）六硼化物と反応しにくい熱分解グラファ
イトを反応障壁材兼発熱体として六硼化物陰極を支持し
、且つ該グラファイト及び六硼化物陰極自体にも通電す
ることにより六硼化物を加熱する熱電子放射陰極、（特
公昭４７−２５９１１号）（２）タングステンなどの高
融点金属線上に六硼化物と反応しにくい炭化ジルコニウ
ムなどの反応障壁層を塗布し、さらにこの障壁層上に六
硼化物粉末を塗布し、タングステン線に通電し、六硼化
物層を加熱、支持した陰極、（特公昭４４−６１８２号
公報）などが提案されている。For example, (1) a hexaboride cathode is supported using pyrolytic graphite, which does not easily react with hexaboride, as a reaction barrier material and a heating element, and the graphite and the hexaboride cathode are also energized to generate hexaboride. A heated thermionic emission cathode (Japanese Patent Publication No. 47-25911) (2) A reaction barrier layer such as zirconium carbide, which does not easily react with hexaboride, is coated on a wire of a high-melting point metal such as tungsten, and further on this barrier layer. A cathode in which hexaboride powder is applied and a tungsten wire is energized to heat and support the hexaboride layer has been proposed (Japanese Patent Publication No. 44-6182).
しかしながら、前記（１）の熱陰極は熱分解グラファイ
トが極めて脆い材料であるために、機械的衝撃に弱いば
かりでなくグラファイトからの熱は導電体支柱の先端か
ら放出されて熱効率がよくない、また衝撃に強くするた
めにグラファイトを太くすると増々犬電力を消費する欠
点がある。However, since the hot cathode (1) is made of pyrolytic graphite, which is an extremely brittle material, it is not only susceptible to mechanical shock, but also has poor thermal efficiency because the heat from the graphite is released from the tip of the conductor support. Making the graphite thicker to make it more resistant to shocks has the disadvantage of consuming more power.
その上グラファイトは加熱時の熱変形により六硼化物が
移動し、電子ビームの位置が不安定となる欠点がある。Furthermore, graphite has the disadvantage that hexaboride moves due to thermal deformation during heating, making the position of the electron beam unstable.
また、（２）の熱陰極は高温で使用した場合、六硼化物
を余り厚く出来ない（厚くすると熱膨脹差により六硼化
物層にクラツクが入る）ことから、六硼化物の蒸発によ
り寿命が短かく、その厚さ２０μの場合、１６００°Ｃ
６０分が使用の限界である。In addition, when the hot cathode (2) is used at high temperatures, the hexaboride layer cannot be made too thick (if it is made thicker, cracks will occur in the hexaboride layer due to the difference in thermal expansion), so the life span will be shortened due to evaporation of the hexaboride. Thus, if the thickness is 20μ, the temperature is 1600°C.
60 minutes is the limit of use.
本発明は、これらの欠点を解決することを目的とするも
のであって、直径１００μ程度以上の棒状体をなす固体
六硼化物と後述の材質で構成された反応障壁材を重層的
に接合して一体化し、この反応障壁材の外側部のみを通
電発熱体となるタングステンなどの高融点金属の箔又は
帯状又は線状体に接触させて挾持することにより機械的
衝撃に強く、且つ消費亀力が小さい、しかも長寿命の六
硼化物系熱電子放射陰極を提供しようとするものである
。The purpose of the present invention is to solve these drawbacks by bonding a solid hexaboride in the form of a rod with a diameter of about 100 μm or more and a reaction barrier material made of the materials described below in a multilayered manner. Only the outer part of this reaction barrier material is energized and held in contact with a foil, strip, or linear body of a high-melting point metal such as tungsten, which serves as a heating element, making it resistant to mechanical shock and reducing power consumption. The purpose of the present invention is to provide a hexaboride-based thermionic emission cathode that has a small amount of energy and has a long life.
すなわち、本発明は固形の六硼化物に固形の反応障壁材
を重層的に接合し、この反応障壁部材の両側又は外周を
高融点金属発熱体で杷持し、この発熱体の両端をそれぞ
れ電流導入端子部に固定してなることを特徴とするもの
である。That is, in the present invention, a solid reaction barrier material is bonded to a solid hexaboride in a multi-layered manner, both sides or the outer periphery of this reaction barrier member are held by a high melting point metal heating element, and both ends of this heating element are connected to each other with an electric current. It is characterized in that it is fixed to the introduction terminal part.
以下、図面によって本発明の実施態様につき説明する。Embodiments of the present invention will be described below with reference to the drawings.
なお、第１〜第３図はそれぞれ本発明の実施例に係る熱
電子放射陰極の斜視図である。Note that FIGS. 1 to 3 are perspective views of thermionic emission cathodes according to embodiments of the present invention, respectively.
１は先端を尖らせた棒状の六硼化物系熱電子放射材、（
２）は反応障壁材であって前記棒状１に接合されて、接
合体３を形成している。1 is a rod-shaped hexaboride-based thermionic emitter with a pointed tip (
2) is a reaction barrier material which is joined to the rod-shaped member 1 to form a joined body 3.
反応障壁材部２は、その側壁２′を２枚の高融点金属発
熱体４で挾持され、該発熱体の両端部５，６は夫々電極
支柱７，８に固着されている。The side wall 2' of the reaction barrier material section 2 is sandwiched between two high melting point metal heating elements 4, and both ends 5 and 6 of the heating elements are fixed to electrode supports 7 and 8, respectively.
前記一対の発熱体４は線状又は箔板状であって重層接合
体３の近傍において点溶接９されている。The pair of heating elements 4 are linear or foil-shaped and are spot-welded 9 in the vicinity of the multilayer assembly 3.
第２図は重層接合体３が角柱であって反応障壁材の側壁
２′に接する一対の発熱体４が線状体である ．場合の
一例であり第３図は、線状発熱体と反応障壁材との接触
を強化すると共に熱伝導を一層向上させたものであって
、発熱体嵌入溝１０が反応障壁材２の外周に設けられて
いる。In FIG. 2, the multilayer assembly 3 is a prismatic column, and the pair of heating elements 4 in contact with the side walls 2' of the reaction barrier material are linear bodies. An example of the case shown in FIG. 3 is one in which the contact between the linear heating element and the reaction barrier material is strengthened and the heat conduction is further improved. It is provided.
本発明において六硼化物系熱電子放射材とはＬａ Ｂ
６に代表される希土類硼化物である。In the present invention, the hexaboride-based thermionic emitter is La B
It is a rare earth boride represented by 6.
また反応障壁材としては、六硼化物系熱電子放射材およ
びタングステン、タンタル、モリブデンなどの発熱体と
高温で反応し難いことが必要であるが、この要求を満足
する物質としては高密度黒鉛、硼化ジルコニウム、窒化
タンタル、炭化タンタルに代表される周期律表ＩＶａ
， Ｖａ ， ＶＩａ族元素の硼化物、窒化物、炭化物
が挙げられる。In addition, the reaction barrier material must be difficult to react at high temperatures with hexaboride-based thermionic emitters and heating elements such as tungsten, tantalum, and molybdenum. Materials that meet this requirement include high-density graphite, Periodic table IVa represented by zirconium boride, tantalum nitride, and tantalum carbide
, Va, and borides, nitrides, and carbides of group VIa elements.
本発明における発熱体は、タングステン、モリブデン等
の高融点金属の箔板又は線条であるから、その全体の形
状は例えば第１図の鎖線の如く任意の形状に加工できる
利点がある。Since the heating element in the present invention is a foil plate or a wire made of a high melting point metal such as tungsten or molybdenum, it has the advantage that its overall shape can be processed into any desired shape, for example as shown by the chain line in FIG.
以下実施例により本発明を説明する。The present invention will be explained below with reference to Examples.
実施例 １
ＬａＢ６焼結体（相対密度９９５％）及び硼化ジルコニ
ウム（相対密度９５．３％）をそれぞれ直径２５ｍｍ，
厚さ１．５ｉｍに加工した。Example 1 A LaB6 sintered body (relative density 995%) and zirconium boride (relative density 95.3%) were each made with a diameter of 25 mm.
It was processed to a thickness of 1.5 mm.
この２枚を重ね合わせ２０３０℃に加熱し、円板の上下
より１５０Ｉｙ／ｆｆｌの圧力で３０分間加圧して両者
を接合した。These two sheets were stacked and heated to 2030° C., and a pressure of 150 Iy/ffl was applied from the top and bottom of the disk for 30 minutes to bond them together.
次いでこの接合体を超音波加工法により直径０．２ｍｉ
ｔｔの丸棒として切り出し、ＬａＢ６先端を電解研磨に
より尖がらせて重層接合体３を得た。Next, this joined body was cut into a diameter of 0.2 mm by ultrasonic processing.
A multilayer assembly 3 was obtained by cutting out a tt round bar and sharpening the LaB6 tip by electrolytic polishing.
電解研磨液には通常のフッ酸一硝酸−アルコール系水溶
液を使用した。An ordinary hydrofluoric acid mononitric acid-alcohol aqueous solution was used as the electrolytic polishing liquid.
次いで厚み０．０５ｍｍ，巾ＬＯｍｗのタンタル箔板２
枚を発熱体４としてこれらの間に反応障壁材２である硼
化ジルコニウムを挿入し、第１図の如くスポット溶接９
し、接合体丸棒を固定した、さらにタンタル箔の両端５
，６をコバール電極７，８に点溶接により固定した。Next, a tantalum foil plate 2 with a thickness of 0.05 mm and a width of LOmw
Zirconium boride, which is a reaction barrier material 2, is inserted between these sheets as a heating element 4, and spot welded 9 as shown in FIG.
Then, the round rod of the joined body was fixed, and both ends of the tantalum foil 5
, 6 were fixed to Kovar electrodes 7 and 8 by spot welding.
この陰極を真空度２×１０−５Ｔｏｒｒ下で連続１００
時間、１６００℃に加熱した。This cathode was continuously heated for 100 minutes under a vacuum degree of 2 x 10-5 Torr.
The mixture was heated to 1600° C. for an hour.
加熱時の所要電力は８．５Ｗであった。加熱後陰極には
何の異常も認められなかった。The power required during heating was 8.5W. No abnormality was observed in the cathode after heating.
比較のためにタンタル箔の代りに黒鉛薄板（厚み０．
５ ｍｍ ）を２枚合わせ、２枚の合わせ面の空間に０
．２ｍｌｌＣ２＋のＬａＢ，棒をさし込み第４図の如き
構造の陰極を作成した。For comparison, a thin graphite plate (thickness: 0.5 mm) was used instead of tantalum foil.
5 mm) and put 0 in the space between the two mating surfaces.
．． A cathode having a structure as shown in FIG. 4 was created by inserting 2 ml C2+ of LaB and a rod.
第４図に於て１２はＬａＢ６チツプ、１３は黒鉛薄板、
１４は黒鉛スペーサーである。In Figure 4, 12 is a LaB6 chip, 13 is a graphite thin plate,
14 is a graphite spacer.
黒鉛薄板とスペーサーの部分はＴａ板を介してコバール
電極板にかしめた。The graphite thin plate and spacer portion were caulked to the Kovar electrode plate via a Ta plate.
この構造の陰極を１６００℃に加熱するには２３．３Ｗ
を要し、しかも加熱後１５分でＬａＢ６チップと黒鉛板
にゆるみが生じ、ＬａＢ６チツプが動いてしまった。To heat a cathode with this structure to 1600℃, it takes 23.3W.
Furthermore, the LaB6 chip and the graphite plate became loose 15 minutes after heating, and the LaB6 chip moved.
実施例，２
ＬａＢ６−ＹＢ６（六硼化イットリウム）系複合焼結体
（ＬａＢ６７ ５重量％）を直径２５ｍｍ，厚さ１．５
間の形状でホットプレス法により作成し、実施例１と同
様な方法、条件下で直径２５ｍ４厚さ１．５框の炭化ジ
ルコニウムの円板に接合した。Example 2 LaB6-YB6 (yttrium hexaboride) based composite sintered body (LaB67 5% by weight) with a diameter of 25 mm and a thickness of 1.5
It was made by hot pressing in a shape between 1 and 2, and was bonded to a zirconium carbide disk with a diameter of 25 m and a thickness of 1.5 frames under the same method and conditions as in Example 1.
次いでこの接合円板より超音波加工法により０．３ｉｍ
口の角柱状の接合体３を切り出し、焼結体先端を実施例
１と同様にして電解研磨により尖らせた。Next, from this bonded disk, 0.3 mm was cut by ultrasonic processing.
A prismatic joined body 3 with a mouth was cut out, and the tip of the sintered body was sharpened by electrolytic polishing in the same manner as in Example 1.
次いで直径０． １ ｙｔｗのタングステン線を発熱体
として第２図の如き構造の陰極を作成しｔラこの陰極を
３Ｘ１ ０−５Ｔｏｒｒ下で常温と１６００℃の間で加
熱、冷却をくり返した。Then the diameter is 0. A cathode having a structure as shown in FIG. 2 was prepared using a tungsten wire of 1 YTW as a heating element, and this cathode was repeatedly heated and cooled between room temperature and 1600 DEG C. under 3.times.10@-5 Torr.
くり返し回数１５０回で陰極に異常は認められなかった
０１６００℃加熱時の消費電力は９．７Ｗであった。No abnormality was observed in the cathode after 150 repetitions.The power consumption during heating at 01600°C was 9.7W.
一方市販のタングステンヘアピン陰極のタングステン細
線上に先ず炭化ジルコニウム粉末を塗布、焼結し、次い
でその上にＬａＢ６−ＹＢ６混合粉末（ＬａＢ６７５ｗ
ｔ％）を塗布、焼結した陰極を作成した。On the other hand, zirconium carbide powder is first applied and sintered on the tungsten wire of a commercially available tungsten hairpin cathode, and then LaB6-YB6 mixed powder (LaB675w
A cathode was prepared by coating and sintering t%).
この際、硼化物層の厚みは１５μであった。この様にし
て作成した陰極を同様な加熱条件でくり返し加熱したと
ころ、くり返し４回目で硼化物層は消失した。At this time, the thickness of the boride layer was 15 μm. When the cathode thus prepared was repeatedly heated under the same heating conditions, the boride layer disappeared after the fourth heating.
第１〜第３図はそれぞれ本発明の実施例に係る熱電子放
射陰極の斜視図である。
第４図は比較例の斜視図である。1 to 3 are perspective views of thermionic emission cathodes according to embodiments of the present invention, respectively. FIG. 4 is a perspective view of a comparative example.
Claims (1)
接合された接合体が、その反応障壁材部のみを電極支柱
間に架設された一対の線状又は箔板状の高融点金属製発
熱体によって挾持されてなる熱電子放射陰甑。 ２ 反応障壁材の外側面に高融点金属製発熱体嵌合用溝
が形成されてなる特許請求の範囲第１項記載の熱電子放
射陰極。 ３ 重層接合体の反応障壁材部が、その外周を高融点金
属製発熱体によって囲撓されて支持されている特許請求
の範囲第１項又は第２項の熱電子放射陰極。[Scope of Claims] 1. A bonded body in which a hexaboride-based thermionic emission material and a reaction barrier material are bonded in a multi-layered manner, with only the reaction barrier material portion being connected to a pair of linear or A thermionic radiation shade that is held between foil plate-shaped heating elements made of high melting point metal. 2. The thermionic emission cathode according to claim 1, wherein a groove for fitting a heating element made of a high melting point metal is formed on the outer surface of the reaction barrier material. 3. The thermionic emission cathode according to claim 1 or 2, wherein the reaction barrier material portion of the multilayer assembly is surrounded and supported at its outer periphery by a heating element made of a high melting point metal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP51015224A JPS5911172B2 (en) | 1976-02-14 | 1976-02-14 | thermionic emission cathode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP51015224A JPS5911172B2 (en) | 1976-02-14 | 1976-02-14 | thermionic emission cathode |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS52107761A JPS52107761A (en) | 1977-09-09 |
| JPS5911172B2 true JPS5911172B2 (en) | 1984-03-14 |
Family
ID=11882883
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP51015224A Expired JPS5911172B2 (en) | 1976-02-14 | 1976-02-14 | thermionic emission cathode |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5911172B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5826766B2 (en) * | 1977-09-30 | 1983-06-04 | 電気化学工業株式会社 | Hot cathode and its manufacturing method |
| JP4958297B2 (en) * | 2007-10-29 | 2012-06-20 | 学 枦山 | Thread breakage prevention tool for sewing machine bobbins |
-
1976
- 1976-02-14 JP JP51015224A patent/JPS5911172B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS52107761A (en) | 1977-09-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US2912611A (en) | Thermionic cathodes | |
| US4482839A (en) | Thermionic emission cathode and preparation thereof | |
| US5444327A (en) | Anisotropic pyrolytic graphite heater | |
| US3389290A (en) | Electron gun device | |
| US10643816B1 (en) | X-ray emitting device comprising a focusing electrode composed of a ceramic-based material | |
| US3134924A (en) | Emissive materials of a metal matrix with molecularly dispersed additives | |
| US4137476A (en) | Thermionic cathode | |
| US3139541A (en) | Generation of power using emissive materials | |
| JPS5911172B2 (en) | thermionic emission cathode | |
| US2740067A (en) | Ceramic vacuum tube | |
| CN1956124B (en) | High efficient cathode assembly | |
| US4843277A (en) | Single crystal emitter with heater wire embedded therein | |
| US4168565A (en) | Method for manufacturing thermionic cathode | |
| GB2057922A (en) | Method of manufacturing a metal cylindrical hermetic sealing member | |
| JP5047062B2 (en) | Thermionic emission cathode | |
| JPS5842141A (en) | Pierce type electron gun | |
| JPS6062034A (en) | Hot-cathode frame body | |
| JPS63241834A (en) | Hot cathode | |
| JPS5830035A (en) | Dot-type cathode | |
| JP2738694B2 (en) | Method for producing impregnated cathode assembly | |
| JP3137406B2 (en) | Manufacturing method of cathode assembly | |
| JP2685835B2 (en) | Manufacturing method of impregnated cathode | |
| WO1984001664A1 (en) | Controlled porosity dispenser cathode | |
| JPS5842142A (en) | Pierce type electron gun | |
| JPS61216222A (en) | Impregnated type cathode composition |