JPH02160694A - Manufacturing method of tungsten single crystal - Google Patents
Manufacturing method of tungsten single crystalInfo
- Publication number
- JPH02160694A JPH02160694A JP31718988A JP31718988A JPH02160694A JP H02160694 A JPH02160694 A JP H02160694A JP 31718988 A JP31718988 A JP 31718988A JP 31718988 A JP31718988 A JP 31718988A JP H02160694 A JPH02160694 A JP H02160694A
- Authority
- JP
- Japan
- Prior art keywords
- tungsten
- single crystal
- temperature
- zirconium oxide
- annealing
- 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
- 239000013078 crystal Substances 0.000 title claims abstract description 39
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 title claims description 40
- 229910052721 tungsten Inorganic materials 0.000 title claims description 37
- 239000010937 tungsten Substances 0.000 title claims description 36
- 238000004519 manufacturing process Methods 0.000 title claims description 15
- 238000000137 annealing Methods 0.000 claims abstract description 14
- 238000001953 recrystallisation Methods 0.000 claims abstract description 11
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical compound [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 claims description 17
- 229910001928 zirconium oxide Inorganic materials 0.000 claims description 17
- 239000000843 powder Substances 0.000 abstract description 5
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 abstract 4
- 238000000034 method Methods 0.000 description 14
- 238000012545 processing Methods 0.000 description 9
- 238000005245 sintering Methods 0.000 description 8
- 238000010438 heat treatment Methods 0.000 description 4
- 239000002019 doping agent Substances 0.000 description 3
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 229910052593 corundum Inorganic materials 0.000 description 2
- 238000005242 forging Methods 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 238000005096 rolling process Methods 0.000 description 2
- 229910001845 yogo sapphire Inorganic materials 0.000 description 2
- 241001474374 Blennius Species 0.000 description 1
- -1 Ni20 Inorganic materials 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
- 150000003755 zirconium compounds Chemical class 0.000 description 1
Landscapes
- Crystals, And After-Treatments Of Crystals (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、タングステン単結晶の製造方法に関する。タ
ングステン単結晶は結晶粒界を有さないため、粒界での
脆化がな（、機械的特性に優れている。このため、各種
構造部品あるいは電子部品として有用である。DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing tungsten single crystals. Since tungsten single crystals do not have grain boundaries, they do not become embrittled at grain boundaries (and have excellent mechanical properties. Therefore, they are useful as various structural parts or electronic parts.
タングステン線あるいは棒を、再結晶温度以上に加熱し
て、結晶を粗大化する単結晶の製造方法は周知である。A method for producing a single crystal in which a tungsten wire or rod is heated above the recrystallization temperature to coarsen the crystal is well known.
例えば、Ｓ、Ｗ、Ｙｉｈ 、 Ｃ，Ｔ、Ｗａｎｇ著のｒ
’ｒｕｎｇｓｔｅｎ、＋第２版（１９８１） １８９ペ
ージには、タングステン棒を１５５０℃で焼鈍後、ｌｕ
ａ／分の速度で棒を移動させながら、２１００℃の加熱
帯を通過させ、再結晶粒をゆっくり成長させて単結晶を
造る方法が述べられている。しかし、この方法では結晶
の成長速度が遅く、大きな単結晶を得るためには時間が
かかり過ぎる欠点がある。また、単結晶の形状も棒状に
限定される欠点がある。For example, r by S. W. Yih and C. T. Wang.
'rungsten, + 2nd edition (1981) page 189 describes that after annealing a tungsten rod at 1550°C, the lu
A method is described in which a single crystal is produced by passing a rod through a heating zone at 2100° C. while moving the rod at a speed of a minute to slowly grow recrystallized grains. However, this method has the disadvantage that the crystal growth rate is slow and it takes too much time to obtain a large single crystal. Furthermore, the shape of the single crystal is also limited to a rod shape.
また、特開昭６１−６１９７ではタングステンにＣａＯ
やＭｇＯを添加して、再結晶温度以上に加熱する単結晶
の製造方法が提案されている石しかし、、この方法にお
いては、これらの添加する酸化物が高温では蒸発、飛散
してしまうために、タングステンの焼結体を製造するに
際して、焼結温度を１８００〜２０００℃以下の温度に
抑えなければならず、焼結時間を長くしなければならな
い上、得られた焼結体の比重も低く、その後の圧延、鍛
造等が困難になる問題がある。In addition, in JP-A-61-6197, tungsten has CaO
However, in this method, these added oxides evaporate and scatter at high temperatures, so When producing a tungsten sintered body, the sintering temperature must be kept below 1800 to 2000°C, the sintering time must be lengthened, and the specific gravity of the obtained sintered body is low. , there is a problem that subsequent rolling, forging, etc. become difficult.
本発明は、前記従来の技術の問題点を解消し、比較的容
易に効率よく単結晶を製造することのできる新規なタン
グステン単結晶の製造方法を提供することを目的とする
。SUMMARY OF THE INVENTION An object of the present invention is to provide a novel method for manufacturing a tungsten single crystal, which solves the problems of the conventional techniques and can manufacture a single crystal relatively easily and efficiently.
本発明者等は、先に、Ａｌ２Ｏ３、Ｋ２Ｏ、ＳｉＯ□を
単身または複合して添加した、いわゆるドープタングス
テンに酸化ジルコニウムを０．Ｏ１〜０．０５重量％添
加し、所定の大きさまで加工後、２６００°Ｃ以上の温
度で焼鈍する単結晶の製造方法を発明（特開昭８２−２
７５０９１） した。その後、更に前記目的達成のため
に検討を重ねてきた結果、タングステンに酸）化ジルコ
ニウムを単身で添加する場合、更に低い焼鈍温度で目的
とする単結晶が得られることを見出し、本発明を完成す
るに至った。The present inventors first added zirconium oxide to so-called doped tungsten, in which Al2O3, K2O, and SiO□ were added singly or in combination. Invented a method for producing single crystals by adding 1 to 0.05% by weight of O, processing them to a predetermined size, and then annealing them at a temperature of 2600°C or higher (Japanese Patent Laid-Open No. 82-2
75091) I did. After that, as a result of further studies to achieve the above objective, it was discovered that when zirconium oxide) was added alone to tungsten, the desired single crystal could be obtained at an even lower annealing temperature, and the present invention was completed. I ended up doing it.
本発明によるタングステン単結晶の製造方法の特徴は、
酸化ジルコニウムを０．０１〜０．１重量％添加したタ
ングステン多結晶体を再結晶温度以上の温度で焼鈍する
ことである。The characteristics of the method for manufacturing tungsten single crystal according to the present invention are as follows:
This method involves annealing a tungsten polycrystalline body to which 0.01 to 0.1% by weight of zirconium oxide is added at a temperature equal to or higher than the recrystallization temperature.
本発明の実施形態の１例は、例えば次のようである。タ
ングステン粉末と酸化ジルコニウム粉末を所定の割合で
混合し、プレス成形後２５００〜３０００℃で焼結して
、タングステンインゴットを得る。An example of an embodiment of the present invention is as follows. Tungsten powder and zirconium oxide powder are mixed at a predetermined ratio, press-molded, and then sintered at 2500 to 3000°C to obtain a tungsten ingot.
次いで、このインゴットを鍛造、圧延、スェージ等の方
法により、所定の形状に加工後、再結晶温度以上の温度
で焼鈍して、目的とする単結晶を得る。Next, this ingot is processed into a predetermined shape by a method such as forging, rolling, or swaging, and then annealed at a temperature equal to or higher than the recrystallization temperature to obtain a desired single crystal.
酸化ジルコニウムの添加は、粉末混合の他、加熱分解に
より酸化ジルコニウムとなるジルコニウム化合物を溶液
として添加し、次いで加熱分解してもよい。プレス、焼
結ならびに加工は、タングステンの場合と同じように一
般的な方法で行なうことができる。In addition to powder mixing, zirconium oxide may be added by adding a zirconium compound that becomes zirconium oxide by thermal decomposition as a solution, and then thermally decomposing it. Pressing, sintering and processing can be carried out in the same manner as in the case of tungsten.
本発明の方法によれば、前記文献ｒＴｕｎｇｓｔｅｎＪ
に記述されている方法とは異なり、温度勾配をつけて、
タングステン棒をゆっくりと移動させながら加熱すると
いうような手間や時間をかける必要がなく、通電あるい
は間接加熱により一度焼鈍するだけで単結晶が得られる
ため、製造効率が非常によい。According to the method of the present invention, the above-mentioned document rTungstenJ
Unlike the method described in , with a temperature gradient,
There is no need to spend time and effort to heat the tungsten rod while slowly moving it, and a single crystal can be obtained by simply annealing it once by applying electricity or indirect heating, so manufacturing efficiency is very high.
また、本発明の方法によれば、酸化ジルコニウムの融点
が２７００℃と高く、焼結時に飛散するおそれがないた
めに、タングステンインゴット製作時の焼結温度が高く
とれ、得られる焼結体の密度も理論密度の９０パ一セン
ト以上にすることができ、以降の加工工程が容易である
。また、焼結時間も３０〜６０分と短くできる。In addition, according to the method of the present invention, the melting point of zirconium oxide is as high as 2700°C, and there is no risk of scattering during sintering, so the sintering temperature can be set high during tungsten ingot production, and the resulting sintered body has a high density. The density can be made to be 90% or more of the theoretical density, and subsequent processing steps are easy. Moreover, the sintering time can be shortened to 30 to 60 minutes.
タングステンに酸化ジルコニウムを単身で添加したとき
は、Ａｌ２Ｏ３、に２０ 、ＳｉＯ□等のいわゆるドー
プ剤を複合で添加したとぎに較べて、単結晶を製造する
焼鈍温度が２００〜５００℃程度低くなる。When zirconium oxide is added alone to tungsten, the annealing temperature for producing a single crystal is about 200 to 500° C. lower than when a so-called dopant such as Al2O3, Ni20, SiO2, etc. is added in combination.
これは、上記ドープ剤を複合で添加したドープタングス
テンに較べ、ドープ剤を添加しない一般のタンゲスケン
では再結晶温度が低くなるためと推察される。また、酸
化ジルコニウムを単身で添加する本発明の方法では、前
記ドープタングステンに酸化ジルコニウムを添加する方
法に較べ、単結晶を得るための酸化ジルコニウム添加量
の範囲が０．０１〜０．１重量％と広くなった。This is presumed to be because the recrystallization temperature of ordinary tungsten to which no dopant is added is lower than that of doped tungsten to which the above-mentioned dopant is added in combination. Furthermore, in the method of the present invention in which zirconium oxide is added alone, the range of the amount of zirconium oxide added to obtain a single crystal is 0.01 to 0.1% by weight, compared to the method in which zirconium oxide is added to doped tungsten. It became wider.
単結晶を製造するときの焼鈍温度は、再結晶温度以上で
あればよいが、低温域では焼鈍時間を長くする必要があ
り、２４００°Ｃ以上とすることが望ましい。また、焼
鈍時の昇温速度も特に規定されるものではないが、昇温
速度の遅いほど大きな単結晶が得られる。粒界移動の始
まる約１０００°Ｃ以上においては６０℃／分以下とす
るのが望ましい。The annealing temperature when producing a single crystal may be equal to or higher than the recrystallization temperature; however, in a low temperature range, it is necessary to lengthen the annealing time, and the annealing temperature is preferably 2400°C or higher. Further, the rate of temperature increase during annealing is not particularly limited, but the slower the rate of temperature increase, the larger the single crystal can be obtained. At temperatures above about 1000°C where grain boundary movement begins, it is desirable to set the speed to 60°C/min or less.
以下実施例に沿って本発明の内容をより詳細に説明する
。The content of the present invention will be explained in more detail below with reference to Examples.
〔実施例１〕
タングステン粉末と酸化ジルコニウム粉末を各種割合で
混合し、圧力１．２ ｔ ｌｃｄでプレス成形した後、
水素中、約３０００℃で６０分焼結して、タングステン
インゴットを得た。このときのインゴットの密度は、約
１８ｇ／ａＩｒ（理論密度の約９３％）であった。次い
で、得られたタングステンインゴットを加工温度１００
０〜１２００℃でスェージング加工し、φ４ｍｍのタン
グステン棒とした。このときの断面減少率は９４％であ
る。なお、断面減少率は以下の式で定義される。[Example 1] After mixing tungsten powder and zirconium oxide powder in various proportions and press-molding at a pressure of 1.2 t lcd,
A tungsten ingot was obtained by sintering in hydrogen at about 3000° C. for 60 minutes. The density of the ingot at this time was about 18 g/aIr (about 93% of the theoretical density). Next, the obtained tungsten ingot was processed at a processing temperature of 100
Swaging processing was performed at 0 to 1200°C to obtain a tungsten rod with a diameter of 4 mm. The area reduction rate at this time is 94%. Note that the area reduction rate is defined by the following formula.
断面減少率＝（加工前の断面積−加工後の断面積）／（
加工前の断面積）
次に、タングステン棒を水素中、２６００℃で焼鈍した
。このとき、２６００℃までの昇温時間は約９０分とし
、２６００℃に達した時点で加熱を止め、放冷した。Section reduction rate = (cross-sectional area before processing - cross-sectional area after processing) / (
Cross-sectional area before processing) Next, the tungsten rod was annealed at 2600°C in hydrogen. At this time, the heating time to 2,600°C was approximately 90 minutes, and when the temperature reached 2,600°C, heating was stopped and allowed to cool.
焼鈍後の結晶の状態を表１に示す。なお、ここでは棒の
横断面を目視し、横断面の結晶の数が１表１
個のものを単結晶とした。Table 1 shows the state of the crystals after annealing. In this case, the cross section of the bar was visually observed, and those with 1 crystal in the cross section were defined as single crystals.
表１から明らかなように、酸化ジルコニウムの含有量力
句、Ｏ１〜０．１重量％の試料では単結晶が得られた。As is clear from Table 1, single crystals were obtained in samples with a zirconium oxide content of O1 to 0.1% by weight.
〔実施例２〕
タングステン粉末に酸化ジル・コニウムを０．０５重量
％混合し、実施例１と同様にして加工し、φ１０鴎の棒
を得た。このときの断面減少率は８６％であった。得ら
れたタングステン棒を実施例１と同様に焼鈍したところ
、タングステン棒は長大な単結晶となった。[Example 2] 0.05% by weight of zirconium oxide was mixed with tungsten powder and processed in the same manner as in Example 1 to obtain a φ10 seaweed rod. The area reduction rate at this time was 86%. When the obtained tungsten rod was annealed in the same manner as in Example 1, the tungsten rod became a long single crystal.
以上説明したように、タングステン多結晶体に酸化ジル
コニウムを添加して焼鈍する本発明の方法によれば、容
易に長大なタングステン単結晶が得られ、その産業上の
利用価値は大きい。As explained above, according to the method of the present invention in which zirconium oxide is added to a tungsten polycrystal and annealed, a long tungsten single crystal can be easily obtained, and its industrial utility value is great.
特許出願人 日本タングステン株式会社１、事件の表示
昭和６３年特許願第３１７１８９号２、発明の名称
タングステン単結晶の製造方法
３、補正をする者
事件との関係 特許出願人
なし
５、補正の対象
（１）特許請求の範囲の欄
（２）発明の詳細な説明の欄
６、補正の内容
（２）発明の詳細な説明の欄
イ、明細書第３百６行〜７行目、同頁１３行目、第５頁
９行目並びに第５頁１６行目記載の１単身」を「単独」
に補正する。Patent applicant: Nippon Tungsten Co., Ltd. 1, Indication of case: 1985 Patent Application No. 317189 2, Title of invention: Process for manufacturing tungsten single crystal 3, Person making the amendment Relationship with the case: No patent applicant 5, Subject of amendment (1) Claims column (2) Detailed explanation of the invention column 6, contents of amendment (2) Detailed explanation of the invention column A, lines 306 to 7 of the specification, same page 13th line, page 5, line 9, and page 5, line 16
Correct to.
口、明細書筒４頁１２行目「プレス、焼結ならびに加工
は、ｊの記載の直後に「通常の」の記載を追加する補正
をする。Page 4 of the specification, line 12, ``Pressing, sintering, and processing'' will be amended by adding the description ``normal'' immediately after the description of j.
ハ、明細書第７頁７行〜第８頁１行目の［なお、ここで
は棒の横断面を目視し、横断面の結晶の数が１個のもの
を単結晶とした。」の記述を［なお、ここでは棒の横断
面を目視し、横断面の結晶の数が１個、ならびに１個の
結晶が棒の横断面の大部分を占める粗大なものを単結晶
とした。」に補正する。C. From page 7, line 7 to page 8, line 1 of the specification [Here, the cross section of the rod was visually observed, and a rod with one crystal in the cross section was considered a single crystal. ” [In this case, the cross section of the rod was visually observed, and a single crystal was defined as one in which the number of crystals in the cross section was 1, and one coarse crystal occupying most of the cross section of the rod. . ”.
二、明細書第７頁に記載の「表１」を別紙のように補正
する。2. "Table 1" stated on page 7 of the specification is amended as shown in the attached sheet.
２、特許請求の範囲
！、タングステン多結晶体を再結晶温度以上に加熱して
結晶を粗大化するタングステン単結晶の製造方法におい
て、前記タングステン多結晶体に酸化ジルコニウムを０
．Ｏ１〜０．１重量％盈亘嘉立工再結晶温度以上の温度
で焼鈍することを特徴とするタングステン単結晶の製造
方法。2. Scope of claims! , a method for producing a tungsten single crystal in which the tungsten polycrystal is heated to a temperature higher than the recrystallization temperature to coarsen the crystal, in which zero zirconium oxide is added to the tungsten polycrystal.
．． A method for producing a tungsten single crystal, which comprises annealing at a temperature equal to or higher than the recrystallization temperature.
Claims (1)
結晶を粗大化するタングステン単結晶の製造方法におい
て、前記タングステン多結晶体に酸化ジルコニウムを０
．０１〜０．１重量％添加して再結晶温度以上の温度で
焼鈍することを特徴とするタングステン単結晶の製造方
法。1. A method for producing a tungsten single crystal in which the tungsten polycrystal is heated to a temperature higher than the recrystallization temperature to coarsen the crystal, in which zero zirconium oxide is added to the tungsten polycrystal.
．． 1. A method for producing a tungsten single crystal, which comprises adding 0.01 to 0.1% by weight and annealing at a temperature equal to or higher than the recrystallization temperature.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP31718988A JPH02160694A (en) | 1988-12-14 | 1988-12-14 | Manufacturing method of tungsten single crystal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP31718988A JPH02160694A (en) | 1988-12-14 | 1988-12-14 | Manufacturing method of tungsten single crystal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02160694A true JPH02160694A (en) | 1990-06-20 |
| JPH0519519B2 JPH0519519B2 (en) | 1993-03-16 |
Family
ID=18085447
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP31718988A Granted JPH02160694A (en) | 1988-12-14 | 1988-12-14 | Manufacturing method of tungsten single crystal |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02160694A (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62275091A (en) * | 1986-05-20 | 1987-11-30 | Nippon Tungsten Co Ltd | Production of tungsten single crystal |
-
1988
- 1988-12-14 JP JP31718988A patent/JPH02160694A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62275091A (en) * | 1986-05-20 | 1987-11-30 | Nippon Tungsten Co Ltd | Production of tungsten single crystal |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0519519B2 (en) | 1993-03-16 |
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