JPS6151002B2 - - Google Patents
Info
- Publication number
- JPS6151002B2 JPS6151002B2 JP7763879A JP7763879A JPS6151002B2 JP S6151002 B2 JPS6151002 B2 JP S6151002B2 JP 7763879 A JP7763879 A JP 7763879A JP 7763879 A JP7763879 A JP 7763879A JP S6151002 B2 JPS6151002 B2 JP S6151002B2
- Authority
- JP
- Japan
- Prior art keywords
- degassing
- plug
- capsule
- sealing
- metal
- 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
- 238000007872 degassing Methods 0.000 claims description 37
- 239000002775 capsule Substances 0.000 claims description 36
- 238000000034 method Methods 0.000 claims description 30
- 239000002184 metal Substances 0.000 claims description 18
- 238000007789 sealing Methods 0.000 claims description 16
- 238000003466 welding Methods 0.000 claims description 15
- 239000000843 powder Substances 0.000 claims description 11
- 239000000463 material Substances 0.000 claims description 7
- 238000001513 hot isostatic pressing Methods 0.000 claims description 6
- 238000000462 isostatic pressing Methods 0.000 claims 1
- 238000005242 forging Methods 0.000 description 6
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 3
- 238000005520 cutting process Methods 0.000 description 3
- 230000007547 defect Effects 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 239000007779 soft material Substances 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 210000003437 trachea Anatomy 0.000 description 1
- 238000005493 welding type Methods 0.000 description 1
Landscapes
- Press-Shaping Or Shaping Using Conveyers (AREA)
- Powder Metallurgy (AREA)
Description
【発明の詳細な説明】
本発明は熱間静水圧プレス法（以下HIP法とい
う）における被処理粉末充填後の金属カプセルの
脱気密封方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for degassing and sealing a metal capsule after filling with powder to be treated in a hot isostatic pressing method (hereinafter referred to as HIP method).
HIP法は、カプセルと称せられる容器内に、金
属粉末あるいはセラミツクス粉末を充填し、これ
を脱気密封して高温高圧ガス雰囲気下で焼結する
方法であり、近年特に難加工性材料の成形技術と
して注目を集めている。一方、カプセル材料とし
ては、金属あるいはガラスが代表的なものである
が、その加工の容易性，取扱いの容易性等の利点
から金属カプセルが一般に使用されている。 The HIP method is a method in which a container called a capsule is filled with metal powder or ceramic powder, the container is degassed and sealed, and then sintered in a high-temperature, high-pressure gas atmosphere. is attracting attention as On the other hand, metal or glass are typical capsule materials, and metal capsules are generally used because of their ease of processing and handling.
この金属カプセルを用いる場合のカプセル密封
法としては、一般に鍛圧法が使用されている。こ
の方法は第１図に示す如く、被処理粉末２を充填
した金属カプセル１内のガスを先ず脱気管３を通
して脱気し、カプセル内が所定の真空度に達する
と脱気管３の適所を一対のハンマー１４，１４′
により熱間で鍛圧して封止し、続いてその鍛圧部
１５をガスあるいは金鋸により切断し、その切断
部を溶接して密封する方法であるが、かかる方法
で実際に鍛圧した場合、その鍛圧部を圧着させる
ことは実質上、不可能であり、切断時に若于の真
空洩れの生じることは避けられなかつた。特に鍛
圧部に粉末が噛み込んでいたりすると鍛圧部は不
完全になり易く、このため切断時の真空洩れも大
きくなり、カプセル内を所定の真空度に保持し得
なくなる場合も多かつた。また、切断部の溶接に
おいても、粉末が鍛圧部に噛み込んでいると溶接
欠陥が発生し易く、この溶接欠陥は、HIP時に溶
接部が破損して高圧の雰囲気ガスがカプセル内に
侵入し、HIP処理の失敗を招く原因ともなつてい
た。 When using this metal capsule, a press method is generally used as a capsule sealing method. As shown in Fig. 1, in this method, the gas in the metal capsule 1 filled with the powder to be treated 2 is first degassed through the degassing tube 3, and when the inside of the capsule reaches a predetermined degree of vacuum, the degassing tube 3 is opened at a suitable position. hammer 14, 14'
This is a method of sealing by hot forging, then cutting the forged part 15 with gas or a hacksaw, and welding the cut part to seal it. It is virtually impossible to press the forging part, and it is inevitable that a vacuum leak will occur during cutting. In particular, if powder is caught in the press part, the press part is likely to become incomplete, resulting in large vacuum leaks during cutting, and it is often impossible to maintain a predetermined degree of vacuum inside the capsule. In addition, when welding a cut part, welding defects are likely to occur if powder gets caught in the forging part, and this welding defect is caused by the welding part breaking during HIP and high-pressure atmospheric gas entering the capsule. This was also a cause of failure in HIP processing.
更にカプセル内の脱気が不完全な状態でHIP処
理すると、製品中に残留ガスによる気孔が発生
し、製品の品質低下を招くことにもなる。 Furthermore, if the HIP process is performed while the capsule is incompletely degassed, residual gas will create pores in the product, leading to a decline in product quality.
かかる脱気密封不良によるHIP失敗あるいは不
良品の発生率はHIP処理に際し決して小さいもの
ではなく、これがHIP製品の歩留り低下コスト上
昇の大きな要因となつている。 The incidence of HIP failure or defective products due to such degassing and sealing failures is not small during HIP processing, and this is a major factor in lowering yields and increasing costs of HIP products.
本発明はかかる現状に鑑み、その改善を図るべ
くなされたものであり、従来の鍛圧による密封に
替えて、プラグのねじ止めによる密封を採用し、
しかもそのプラグを脱気管に強固に噛み込ませる
ことにより密封の安定化を計ると共に、HIP処理
時においてもその密封が維持されるよう、両者溶
接により一体化する点に特徴を有する。 In view of the current situation, the present invention was made to improve the situation, and instead of the conventional sealing by forging, sealing by screwing the plug is adopted,
Moreover, the plug is firmly inserted into the degassing pipe to stabilize the seal, and the two are welded together so that the seal is maintained even during HIP processing.
以下、添付図面により本発明を更に詳細に説明
する。 Hereinafter, the present invention will be explained in more detail with reference to the accompanying drawings.
第２図は本発明方法の一実施例を示す断面図
で、本発明で使用するカプセル１の脱気管３の内
面には雌ねじ４とこれに続くテーパー部５とが形
成されており、該脱気管内に挿入するプラグ８に
は雄ねじ６とその下方にエツジ部７及びロツド１
０が形成されている。プラグ８の脱気管３への装
着の際には、先ず図示の如く脱気管３を内包する
ように真空容器１２を配置し、該容器内をパツキ
ン１７にて完全にシールした状態でノズル１６に
接続した真空ポンプ（図示せず）により、カプセ
ル内を脱気管３を通して脱気すると共に容器１２
内も脱気する。この真空容器１２には前記プラグ
８を容器内に保持するハンドル１３が設けられて
おり、プラグ８が脱気管３の真上に位置するよう
に真空容器１２はその内側に設けられているガイ
ド１８により案内配置される。 FIG. 2 is a cross-sectional view showing one embodiment of the method of the present invention, in which a female thread 4 and a tapered portion 5 following this are formed on the inner surface of the degassing tube 3 of the capsule 1 used in the present invention. A plug 8 to be inserted into the trachea has a male thread 6 and an edge portion 7 and a rod 1 below it.
0 is formed. When attaching the plug 8 to the deaeration pipe 3, first arrange the vacuum container 12 so as to enclose the deaeration pipe 3 as shown in the figure, and then attach the vacuum container 12 to the nozzle 16 with the inside of the container completely sealed with the packing 17. A connected vacuum pump (not shown) evacuates the inside of the capsule through the degassing pipe 3 and also removes air from the container 12.
Also evacuate the inside. This vacuum container 12 is provided with a handle 13 for holding the plug 8 inside the container, and the vacuum container 12 is provided with a guide 18 provided inside the vacuum container 12 so that the plug 8 is positioned directly above the degassing tube 3. Guided and placed.
カプセル１内及び真空容器１２内が所定の真空
度に達すると、その真空度を維持したままハンド
ル１３を下降回転させてプラグ８を脱気管３に螺
合装着する。ここで、プラグ８は脱気管３の材料
より硬質の材料、例えばカプセル及び脱気管を軟
鋼等の軟質材で形成し、プラグをステンレス等の
硬質材で形成しておくことにより第３図に示すよ
うにプラグ８のエツジ部７は脱気管３のテーパー
部５に噛み込み、真空容器１２を取り外してもカ
プセル１内はプラグと脱気管のねじ部と噛み込み
部とにより完全に密封されているので真空洩れは
なく、初期の真空度が維持されることになる。 When the inside of the capsule 1 and the inside of the vacuum container 12 reach a predetermined degree of vacuum, the handle 13 is rotated downward while maintaining the degree of vacuum, and the plug 8 is screwed into the degassing tube 3. Here, the plug 8 is made of a harder material than the material of the deaeration pipe 3, for example, the capsule and the deaeration pipe are made of a soft material such as mild steel, and the plug is made of a hard material such as stainless steel, as shown in FIG. As shown, the edge part 7 of the plug 8 is caught in the tapered part 5 of the degassing tube 3, and even if the vacuum container 12 is removed, the inside of the capsule 1 is completely sealed by the plug, the threaded part of the degassing tube, and the biting part. Therefore, there is no vacuum leak and the initial vacuum level is maintained.
次にプラグを脱気管に装着するとプラグと脱気
管とを周溶接９により溶着して一体化させ、脱気
密封を完了する。この周溶接９は従来よりこの種
の溶接に使用される溶加材を用いないTIG溶接で
も良いが、ねじ部４，６をできるだけ溶融させず
に溶着することが溶接工程での真空洩れ防止対策
上好ましいから、脱気管３及びプラグ８の上端溶
接部には予め周溶接開先１１，１１′を形成して
MLG溶接あるいはCO2溶接により溶着金属を形
成することが望ましい。 Next, when the plug is attached to the deaeration pipe, the plug and the deaeration pipe are welded and integrated by circumferential welding 9, and the deaeration sealing is completed. This circumferential welding 9 may be done by TIG welding, which does not use filler metal, which is conventionally used in this type of welding, but it is important to weld the threaded parts 4 and 6 without melting them as much as possible to prevent vacuum leakage in the welding process. Since it is preferable, circumferential weld grooves 11 and 11' are formed in advance at the upper end welds of the degassing pipe 3 and the plug 8.
It is preferable to form the weld metal by MLG welding or CO 2 welding.
また、プラグ８の下部に設けたロツド１０は、
第３図に示すようにプラグ装着時にカプセル１内
に突入しない程度の長さを有しており、これは
HIP処理時に脱気管３が外圧により大きく変形し
て破損するのを防止するためのものであり、この
ロツド１０が脱気管３内に存在することにより、
脱気管がHIP時に押圧されて変形してもロツド１
０により内側から支持されるもので脱気管の大き
な変形が防止され、従つて脱気管の破損とこれに
よるHIP失敗は防止されることになる。 In addition, the rod 10 provided at the bottom of the plug 8 is
As shown in Figure 3, the plug has a length that does not penetrate into the capsule 1 when attached.
This is to prevent the degassing tube 3 from being significantly deformed and damaged by external pressure during HIP processing, and by having this rod 10 inside the degassing tube 3,
Even if the deaeration pipe is pressed and deformed during HIP, the rod 1
0 prevents large deformation of the degassing tube, thereby preventing breakage of the degassing tube and HIP failure due to this.
また、カプセル内の脱気に際し、カプセルを加
熱しながら脱気すると、カプセル内の粉末粒子間
のガスのみならず、粉末粒子に吸着されているガ
ス分子も排気されるため、カプセル内の真空度は
一層向上する。 In addition, when degassing the capsule while heating it, not only the gas between the powder particles inside the capsule but also the gas molecules adsorbed to the powder particles are exhausted, which increases the vacuum level inside the capsule. will further improve.
次に、本発明方法の実施例を示す。 Next, examples of the method of the present invention will be shown.
（実施例）
ねじ部内径d118.6mm、ねじ部長さ20mm、テーパ
ー部長さ８mm、下部内径d210mmの脱気管を有する
軟鋼製カプセル内にハイス粉末を充填し、第２図
に示す真空容器１２を用いて真空度0.02torrまで
脱気し、その真空度を維持した状態で、低合金鋼
材（SNCM8）で形成したねじ長さ15mm、エツジ
部長l8mmのプラグを装着し、これを一旦大気圧下
に取り出して内部真空度を測定したところ、初期
の0.02torrが維持されていた。(Example) A vacuum vessel shown in Fig. 2 was prepared by filling a mild steel capsule with a degassing pipe with an inner diameter of the thread part d 1 of 18.6 mm, a length of the thread part of 20 mm, a taper part length of 8 mm, and a lower inner diameter of d 2 of 10 mm. 12 to a vacuum level of 0.02 torr, and while maintaining the vacuum level, a plug made of low-alloy steel (SNCM8) with a screw length of 15 mm and an edge length of l8 mm was attached, and the plug was once brought to atmospheric pressure. When I took it out and measured the internal vacuum level, I found that the initial level of 0.02 torr was maintained.
一方、軟鋼製カプセルを0.02torrまで脱気し、
鍛圧法により熱間鍛圧した後、鍛圧部を金鋸によ
り切断し、その内部真空度を測定したところ、
0.2torrにまで真空度が低下していた。 Meanwhile, the mild steel capsule was degassed to 0.02 torr.
After hot forging using the forging method, the forged part was cut with a hacksaw and the internal vacuum degree was measured.
The degree of vacuum had dropped to 0.2 torr.
以上の如く本発明方法によれば、脱気管内に脱
気管材料よりも硬質の材料で形成したプラグを螺
着すると同時に両者を噛み合わせているため、初
期のカプセル内真空度は安定して維持されること
になり、また両者を溶着して一体化しているから
HIP処理時においてもその真空度は充分、維持さ
れ、脱気不足、密封不良の心配はなく、従つて従
来の密封方式に比しHIP製品の歩留りが著しく向
上し、その品質も安定化する等、HIP技術の実用
化促進に大きく貢献することが期待される。 As described above, according to the method of the present invention, the plug made of a material harder than the material of the deaeration pipe is screwed into the deaeration pipe and the two are engaged at the same time, so that the initial vacuum level inside the capsule is maintained stably. This is because the two are welded together and integrated.
Even during HIP processing, the degree of vacuum is maintained sufficiently, and there is no need to worry about insufficient degassing or poor sealing. Therefore, compared to conventional sealing methods, the yield of HIP products is significantly improved and the quality is stabilized. It is expected that this will greatly contribute to the promotion of practical application of HIP technology.
第１図は従来のカプセル密封法を示す概略図、
第２図は本発明方法の一実施例を示す要部縦断面
図、第３図は本発明方法により密封された脱気管
部の状態を示す縦断面図である。
１……金属カプセル、２……被処理粉末、３…
…脱気管、４……雌ねじ、５……テーパー部、６
……雄ねじ、７……エツジ部、８……プラグ、９
……周溶接、１０……ロツド、１１，１１……周
溶接開先、１２……真空容器。
Figure 1 is a schematic diagram showing the conventional capsule sealing method;
FIG. 2 is a longitudinal cross-sectional view of a main part showing an embodiment of the method of the present invention, and FIG. 3 is a longitudinal cross-sectional view showing the state of a degassing pipe section sealed by the method of the present invention. 1...metal capsule, 2...powder to be treated, 3...
...Degassing pipe, 4...Female thread, 5...Tapered part, 6
... Male thread, 7 ... Edge part, 8 ... Plug, 9
... Circumferential welding, 10... Rod, 11, 11... Circumferential welding groove, 12... Vacuum vessel.
Claims (1)
粉末２を充填し、脱気密封後、これを高温高圧ガ
ス雰囲気下で熱間静水圧プレス処理する方法にお
いて、前記金属カプセル１を脱気密封するに際し
前記脱気管３の内面に雌ねじ４とこれに続くテー
パー部５とを形成し、該脱気管３に螺着されるプ
ラグ８には雄ねじ６とその下部にエツジ部７とを
形成すると共に、該プラグ８は前記脱気管３より
硬質の材料となし、前記金属カプセル内を脱気管
を通して脱気した後、脱気下で前記プラグ８をそ
のエツジ部７が脱気管のテーパー部５に噛み込む
ように螺着し、しかる後、前記脱気管３とプラグ
８との上端部を周溶接９により溶着することを特
徴とする熱間静水圧プレス法における金属カプセ
ルの脱気密封方法。 ２ プラグ８の先端に金属カプセル内に突入しな
い程度の長さを有するロツド１０が設けられてい
る特許請求の範囲第１項記載の熱間静水圧プレス
法における金属カプセルの脱気密封方法。 ３ 脱気管３の上端部及びプラグ８の上端部に
夫々対応する周溶接用開先１１，１１′が形成さ
れている特許請求の範囲第１項又は第２項記載の
熱間静水圧プレス法における金属カプセルの脱気
密封方法。 ４ 脱気管３を内包する如く真空容器１２を金属
カプセルに装着し、該容器内でプラグ８を脱気管
に螺着する特許請求の範囲第１項，第２項又は第
３項記載の熱間静水圧プレス法における金属カプ
セルの脱気密封方法。 ５ カプセルを加熱しつつ脱気する特許請求の範
囲第１項乃至第４項の何れか各項記載の熱間静水
圧プレス法における金属カプセルの脱気密封方
法。[Scope of Claims] 1. A method in which a powder to be treated 2 is filled into a metal capsule 1 having a degassing tube 3, and after being degassed and sealed, the powder is subjected to hot isostatic pressing in a high temperature and high pressure gas atmosphere. When degassing and sealing the capsule 1, a female thread 4 and a tapered part 5 are formed on the inner surface of the deaeration pipe 3, and a plug 8 screwed onto the deaeration pipe 3 has a male thread 6 and an edge part below it. 7, and the plug 8 is made of a harder material than the degassing tube 3, and after degassing the interior of the metal capsule through the degassing tube, the plug 8 is removed under degassing so that its edge portion 7 becomes the degassing tube. The degassing of the metal capsule in the hot isostatic pressing method is characterized in that the degassing tube 3 and the plug 8 are screwed together so as to fit into the tapered part 5 of the degassing tube 3, and then the upper ends of the degassing tube 3 and the plug 8 are welded together by circumferential welding 9. Hermetic sealing method. 2. A method for degassing and sealing a metal capsule in a hot isostatic pressing method according to claim 1, wherein a rod 10 having a length that does not penetrate into the metal capsule is provided at the tip of the plug 8. 3. Hot isostatic pressing method according to claim 1 or 2, in which grooves 11 and 11' for circumferential welding are formed at the upper end of the degassing pipe 3 and the upper end of the plug 8, respectively. A method for degassing and sealing metal capsules. 4. The hot-temperature treatment according to claim 1, 2, or 3, wherein the vacuum container 12 is attached to a metal capsule so as to enclose the deaeration pipe 3, and the plug 8 is screwed to the deaeration pipe within the container. A method for degassing and sealing metal capsules using the isostatic pressing method. 5. A method for degassing and sealing a metal capsule in a hot isostatic pressing method according to any one of claims 1 to 4, in which the capsule is degassed while being heated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7763879A JPS563602A (en) | 1979-06-19 | 1979-06-19 | Deaerating and hermetic sealing method of metal capsule in hot hydrostatic pressing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7763879A JPS563602A (en) | 1979-06-19 | 1979-06-19 | Deaerating and hermetic sealing method of metal capsule in hot hydrostatic pressing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS563602A JPS563602A (en) | 1981-01-14 |
| JPS6151002B2 true JPS6151002B2 (en) | 1986-11-07 |
Family
ID=13639432
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7763879A Granted JPS563602A (en) | 1979-06-19 | 1979-06-19 | Deaerating and hermetic sealing method of metal capsule in hot hydrostatic pressing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS563602A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0233602U (en) * | 1988-08-26 | 1990-03-02 | ||
| JPH0233604U (en) * | 1988-08-26 | 1990-03-02 | ||
| JPH0410702U (en) * | 1990-05-16 | 1992-01-29 |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3099829B2 (en) * | 1990-08-08 | 2000-10-16 | 株式会社神戸製鋼所 | Manufacturing method of capsule for isotropic pressure treatment |
| CN102554571B (en) * | 2011-12-31 | 2014-03-05 | 宁波江丰电子材料有限公司 | Sealing method for degassing tube |
| KR102105807B1 (en) * | 2020-02-24 | 2020-05-04 | (주)에스엔에이치 | Tube sealing apparatus for degassing of the HIP process |
-
1979
- 1979-06-19 JP JP7763879A patent/JPS563602A/en active Granted
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0233602U (en) * | 1988-08-26 | 1990-03-02 | ||
| JPH0233604U (en) * | 1988-08-26 | 1990-03-02 | ||
| JPH0410702U (en) * | 1990-05-16 | 1992-01-29 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS563602A (en) | 1981-01-14 |
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