JPH04218601A - Method for storing titanium powder mixture - Google Patents
Method for storing titanium powder mixtureInfo
- Publication number
- JPH04218601A JPH04218601A JP3077514A JP7751491A JPH04218601A JP H04218601 A JPH04218601 A JP H04218601A JP 3077514 A JP3077514 A JP 3077514A JP 7751491 A JP7751491 A JP 7751491A JP H04218601 A JPH04218601 A JP H04218601A
- Authority
- JP
- Japan
- Prior art keywords
- titanium
- mixed powder
- powder
- vacuum
- storing
- 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.)
- Pending
Links
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 title claims description 38
- 238000000034 method Methods 0.000 title claims description 25
- 239000000203 mixture Substances 0.000 title abstract description 5
- 239000000843 powder Substances 0.000 claims abstract description 14
- 239000011812 mixed powder Substances 0.000 claims description 45
- 239000010936 titanium Substances 0.000 claims description 33
- 229910052719 titanium Inorganic materials 0.000 claims description 31
- 229910001069 Ti alloy Inorganic materials 0.000 claims description 10
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract description 16
- 239000001301 oxygen Substances 0.000 abstract description 16
- 229910052760 oxygen Inorganic materials 0.000 abstract description 16
- 238000010301 surface-oxidation reaction Methods 0.000 abstract description 4
- 230000006866 deterioration Effects 0.000 abstract description 2
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 abstract 2
- 229920002554 vinyl polymer Polymers 0.000 abstract 2
- 230000003247 decreasing effect Effects 0.000 abstract 1
- 238000003860 storage Methods 0.000 description 9
- 238000000465 moulding Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 239000000314 lubricant Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910000883 Ti6Al4V Inorganic materials 0.000 description 1
- 229910000756 V alloy Inorganic materials 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005238 degreasing Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000002845 discoloration Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 230000002123 temporal effect Effects 0.000 description 1
- 150000003608 titanium Chemical class 0.000 description 1
Landscapes
- Powder Metallurgy (AREA)
- Preventing Corrosion Or Incrustation Of Metals (AREA)
Abstract
Description
【０００１】0001
【産業上の利用分野】この発明は、チタン混合粉末の保
管方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a method for storing mixed titanium powder.
【０００２】0002
【従来の技術】高度の焼結密度を有する焼結チタン合金
（Ｔｉ−６Ａｌ−４Ｖ、Ｔｉ−６Ａｌ−６Ｖ−２Ｓｎ、
Ｔｉ−６Ａｌ−２Ｓｎ−４Ｚｒ−６Ｍｏ等）を製造する
ための技術が、従来から種々開発されている。その中で
、通常のプレス成形を行なう場合には、図３の工程図に
示すような工程で行なわれている。すなわち、まずチタ
ン混合粉末（チタン粉末とマスターアロイ、例えばＡｌ
−Ｖ合金の粉末の混合されたもの）の調整２１および金
型潤滑剤の混合２２を行なった後、金型に潤滑剤を塗布
２３するとともに、チタン混合粉末を金型に装入２４し
、プレス成形２５を行なう。そして、成形品の脱脂２６
を行なった後、成形品を焼結２７する。[Prior Art] Sintered titanium alloys (Ti-6Al-4V, Ti-6Al-6V-2Sn, Ti-6Al-6V-2Sn,
Various techniques for producing Ti-6Al-2Sn-4Zr-6Mo, etc.) have been developed in the past. Among these, when performing normal press molding, the process is performed as shown in the process diagram of FIG. 3. That is, first, titanium mixed powder (titanium powder and master alloy, such as Al
After adjusting 21 the mixture of -V alloy powder and mixing 22 the mold lubricant, the mold is coated with lubricant 23, and the titanium mixed powder is charged into the mold 24, Press molding 25 is performed. Then, degreasing the molded product 26
After performing this, the molded product is sintered 27.
【０００３】ところで、上述したような焼結チタン合金
の製造に使用するチタン混合粉末は、工程の都合上成形
する前に、長期に保管する必要が生じることがある。酸
素との親和性の強いチタン材は、大気に触れた状態で保
管した場合、２〜３週間で表面酸化が進み、これを焼結
した焼結チタン合金の表面には、赤色ないしは黒色の変
色部が発生し、機械的強度が劣化するという問題が生じ
るおそれがある。[0003] Incidentally, the titanium mixed powder used for producing the above-mentioned sintered titanium alloy may need to be stored for a long period of time before being molded due to process constraints. If titanium material has a strong affinity for oxygen and is stored in contact with the atmosphere, surface oxidation will progress in 2 to 3 weeks, and the surface of the sintered titanium alloy produced by sintering this material will have a red or black discoloration. There is a possibility that the problem of mechanical strength deterioration may occur.
【０００４】従来、チタン混合粉末の保管は、図４に示
すような方法で行なっていた。図４は従来のチタン混合
粉末を収容した保管容器の断面図であるが、図中３０は
容器、３１は缶体、３２は蓋、３３はシ−ルバンド、３
４はビニ−ル袋、３５は燒結チタン合金製造用の混合粉
末である。混合粉末３５を使用するにあたっては、シ−
ルバンド３３を外して蓋３２を開け、ビニ−ル袋３４に
封入された混合粉末３５を取り出す。そして、混合粉末
３５を取り出した後は、ビニ−ル袋３４の開口部を閉じ
、蓋３２をかけシ−ルバンド３３を掛けて容器３０を閉
じる。[0004] Conventionally, titanium mixed powder has been stored using a method as shown in FIG. FIG. 4 is a cross-sectional view of a conventional storage container containing mixed titanium powder, in which 30 is a container, 31 is a can body, 32 is a lid, 33 is a seal band, 3
4 is a plastic bag, and 35 is a mixed powder for producing sintered titanium alloy. When using the mixed powder 35, please
Remove the rubber band 33, open the lid 32, and take out the mixed powder 35 sealed in the plastic bag 34. After taking out the mixed powder 35, the opening of the plastic bag 34 is closed, the lid 32 is put on, and the seal band 33 is hung to close the container 30.
【０００５】[0005]
【発明が解決しようとする課題】容器３０を開けて混合
粉末３５を取り出した後、容器３０に保管している混合
粉末３５の酸素濃度の時間的変化を、Ｔｉ粉末：９０ｗ
ｔ％， ６０Ａｌ−４０Ｖ粉末：１０ｗｔ％の混合粉末
について調査したところ、混合粉末３５を取り出した直
後には０．１５Ｗｔ％であったものが、１ケ月後には０
．２３Ｗｔ％、６ケ月後には０．２８Ｗｔ％と徐々に増
加していることが分かった。そして、このように酸素濃
度が種々異なる混合粉末を成形、燒結して製品にして、
その機械的性質を調べてみると、図５のグラフに示すよ
うに、特に衝撃値（２０℃における吸収エネルギー）が
、混合粉末の酸素濃度が０．２５ｗｔ％を超えると極端
に低下することが分かった。したがって、前述した６カ
月保管した後の混合粉末は、製品にした場合、機械的性
質に問題を生じる虞があるという問題点があった。[Problems to be Solved by the Invention] After opening the container 30 and taking out the mixed powder 35, the change over time of the oxygen concentration of the mixed powder 35 stored in the container 30 is determined by comparing the Ti powder: 90w.
t%, 60Al-40V powder: When investigating the mixed powder of 10 wt%, it was 0.15 wt% immediately after taking out the mixed powder 35, but after one month it was 0.
．． It was found that it gradually increased to 23 Wt% and 0.28 Wt% after 6 months. Then, mixed powders with various oxygen concentrations are molded and sintered to make products.
When we investigated its mechanical properties, we found that, as shown in the graph of Figure 5, the impact value (absorbed energy at 20°C) in particular drops dramatically when the oxygen concentration of the mixed powder exceeds 0.25 wt%. Do you get it. Therefore, the above-mentioned mixed powder after being stored for 6 months has a problem in that when it is made into a product, there is a risk of problems in mechanical properties.
【０００６】本発明はかかる事情に鑑みてなされたもの
で、長期間にわたって表面酸化を生じさせないチタン混
合粉末の保管方法を提供することを目的とする。The present invention was made in view of the above circumstances, and an object of the present invention is to provide a method for storing a titanium mixed powder that does not cause surface oxidation for a long period of time.
【０００７】[0007]
【課題を解決するための手段】本発明に係るチタン混合
粉末の保管方法は、焼結チタン合金を素粉末混合法によ
り製造する際に使用するチタン混合粉末の保管方法にお
いて、内部圧力が１０−６〜２０Ｔｏｒｒの真空状態に
保持された気密容器中に、チタン混合粉末を保管するも
のである。[Means for Solving the Problems] A method for storing a mixed titanium powder according to the present invention is a method for storing a mixed titanium powder used when producing a sintered titanium alloy by a raw powder mixing method, in which an internal pressure of 10 - The titanium mixed powder is stored in an airtight container maintained in a vacuum state of 6 to 20 Torr.
【０００８】[0008]
【作用】本発明に係るチタン混合粉末の保管方法は、焼
結チタン合金を素粉末混合法により製造する際に使用す
るチタン混合粉末の保管方法において、内部圧力が１０
−６〜２０Ｔｏｒｒの真空状態に保持された気密容器中
に、チタン混合粉末を保管するようにしている。このよ
うにして保管するのは、次の理由によるものである。す
なわち、前述したように、酸素濃度の高い雰囲気中でチ
タン混合粉末を保管すると、チタン混合粉末の酸素濃度
が徐々に高まり、６ケ月後には衝撃値が極端に低下する
ことが分かった。そして、衝撃値が極端に低下する酸素
濃度は、図５に示すように、０．２５Ｗｔ％を超える範
囲であることが分かったので、６ケ月保管後においても
、チタン混合粉末の酸素濃度が０．２５Ｗｔ％を超えな
い雰囲気は、どのような条件であるのか、保管容器中の
真空度を種々変化させて調査した。そして、その結果保
管容器中の真空度が２０Ｔｏｒｒ以下になるような圧力
下で保管すれば、チタン混合粉末の酸素濃度が０．２５
Ｗｔ％を超えないということが分かった。[Function] The method for storing a titanium mixed powder according to the present invention is a method for storing a titanium mixed powder used when producing a sintered titanium alloy by a raw powder mixing method.
The titanium mixed powder is stored in an airtight container maintained in a vacuum state of -6 to 20 Torr. The reason for storing it in this way is as follows. That is, as described above, it has been found that when titanium mixed powder is stored in an atmosphere with a high oxygen concentration, the oxygen concentration of the titanium mixed powder gradually increases, and the impact value drops extremely after 6 months. As shown in Figure 5, it was found that the oxygen concentration at which the impact value drops extremely is in a range exceeding 0.25 Wt%. The conditions for an atmosphere that does not exceed .25 Wt% were investigated by varying the degree of vacuum in the storage container. As a result, if the titanium mixed powder is stored under pressure such that the degree of vacuum in the storage container is 20 Torr or less, the oxygen concentration of the titanium mixed powder will be 0.25
It was found that it does not exceed Wt%.
【０００９】なお、それ以上真空度を高めれば当然チタ
ン混合粉末の酸素濃度は低くなるが、過度な高真空の状
態をつくりだすのは経済的に不利になるので、真空度の
上限は経済的に問題のない１０−６Ｔｏｒｒ（ロータリ
ー拡散でひける下限）とした。[0009] Note that if the degree of vacuum is increased further, the oxygen concentration in the titanium mixed powder will naturally decrease, but creating an excessively high vacuum state is economically disadvantageous, so the upper limit of the degree of vacuum must be set economically. It was set to 10-6 Torr (the lower limit that can be reduced by rotary diffusion), which is not a problem.
【００１０】0010
【実施例】本発明の１実施例のチタン混合粉末の保管方
法を、図１に基づき説明する。図１は本発明の１実施例
のチタン混合粉末の保管方法に使用する保管容器の縦断
面図である。図中、１０は気密容器で、缶体１および蓋
２により構成されている。蓋２と缶体１はシ−ルリング
４を有するシ−ルバンド３により狭着されて、気密性が
保持されている。蓋２には気密容器１０内の圧力が支持
される圧力計５および真空ポンプ（図示せず）に連結さ
れた導管６が設けられている。前記気密容器内に棚段１
１およびこれを支持する支柱１２が設けられ、棚段１１
に燒結チタン合金用のチタン混合粉末１４が装入された
ビニ−ル袋１３が複数個、載置されている。EXAMPLE A method for storing a titanium mixed powder according to an example of the present invention will be explained based on FIG. FIG. 1 is a longitudinal sectional view of a storage container used in a method for storing titanium mixed powder according to an embodiment of the present invention. In the figure, 10 is an airtight container, which is composed of a can body 1 and a lid 2. The lid 2 and the can body 1 are tightly connected by a seal band 3 having a seal ring 4 to maintain airtightness. The lid 2 is provided with a pressure gauge 5 for supporting the pressure inside the airtight container 10 and a conduit 6 connected to a vacuum pump (not shown). There is a shelf 1 in the airtight container.
1 and a column 12 that supports it, the shelf 11
A plurality of plastic bags 13 each containing a titanium mixed powder 14 for sintered titanium alloy are placed thereon.
【００１１】以上のように構成された本発明の方法を実
施する気密容器の作用について説明する。１カ月以上の
保管を要する粉体については、気密容器１０の中に収容
して保管する。棚段１１を設けた理由は缶体内の気体の
流通性をよくするためである。収容されたチタン混合粉
末１４は使用の都度、必要量を気密容器１０から取り出
され、残りは再び気密容器へ収容される。そして、蓋２
と缶体１の間には、シ−ルリング４が嵌装されておりシ
−ルバンド３によって蓋２と缶体１をきつく圧着するよ
うにしているので、気密容器１０の気密性は保持される
ようになっている。[0011] The operation of the airtight container configured as above for carrying out the method of the present invention will be explained. Powder that requires storage for one month or more is stored in an airtight container 10. The reason for providing the shelves 11 is to improve the gas flow inside the can. The required amount of the contained titanium mixed powder 14 is taken out from the airtight container 10 each time it is used, and the remainder is stored in the airtight container again. And lid 2
A seal ring 4 is fitted between the lid 2 and the can body 1, and the seal band 3 tightly presses the lid 2 and the can body 1, so that the airtightness of the airtight container 10 is maintained. It looks like this.
【００１２】蓋２により缶体１を密閉した後、導管６に
連結された真空ポンプにより缶体の圧力を低下させ、１
０−６〜２０Ｔｏｒｒの真空度に保持する。このような
真空度に保持することにより、気密容器内の酸素濃度は
低下するので、前記ビニ−ル袋内の混合粉末１４の酸化
が防止される。一度、開放されてチタン混合粉末１４を
一部取り出したビニ−ル袋１３のシ−ル部は、部分的に
開放できる構造とし、装入されている混合粉末１４中の
ガスが抜け易くすることが望ましい。After the can body 1 is sealed with the lid 2, the pressure of the can body is reduced by a vacuum pump connected to the conduit 6, and the can body 1 is sealed.
The degree of vacuum is maintained at 0-6 to 20 Torr. By maintaining the vacuum at such a degree, the oxygen concentration within the airtight container is reduced, thereby preventing oxidation of the mixed powder 14 within the plastic bag. Once opened, the sealed portion of the plastic bag 13 from which a portion of the titanium mixed powder 14 has been taken out is structured so that it can be partially opened, so that the gas in the charged mixed powder 14 can easily escape. is desirable.
【００１３】上記実施例について、チタン混合粉末１４
の酸素濃度の時間的変化について、真空度を種々変えて
調査した結果を、表１および図２に示す。比較のため、
前述の従来例についても示してある。本実施例の混合粉
末１４は従来例と同様に、Ｔｉ粉末：９０ｗｔ％， ６
０Ａｌ−４０Ｖ粉末：１０ｗｔ％の混合粉である。表１
および図２中、貯蔵方法はそれぞれ、保持された気密容
器１０内の圧力を示すものである。また従来例は前述の
従来例の項で説明した通りのものである。Regarding the above example, titanium mixed powder 14
Table 1 and FIG. 2 show the results of investigating the temporal change in oxygen concentration at various degrees of vacuum. For comparison,
The above-mentioned conventional example is also shown. The mixed powder 14 of this example is similar to the conventional example, and includes Ti powder: 90 wt%, 6
0Al-40V powder: 10 wt% mixed powder. Table 1
In FIG. 2 and FIG. 2, the storage method indicates the pressure inside the airtight container 10 held. Further, the conventional example is as explained in the section of the conventional example above.
【００１４】[0014]
【表１】[Table 1]
【００１５】表１に示されてある通り、本実施例による
酸素濃度の低下の効果は明らかである。本実施例によれ
ば、少なくとも６カ月まで、製品の機械的性質を損なう
ことなく保管することができる。As shown in Table 1, the effect of lowering the oxygen concentration according to this example is clear. According to this example, the product can be stored for at least 6 months without damaging its mechanical properties.
【００１６】[0016]
【発明の効果】本発明によるチタン混合粉末の保管方法
によれば、真空度を１０−６〜２０Ｔｏｒｒに保持され
た気密容器にチタン混合粉末を保管するので、チタン混
合粉末の酸素濃度は長期にわたって大きく増加すること
なく、このチタン混合粉末を原料として製造されたチタ
ン合金の機械的性質が低下するという問題は生じない。According to the method for storing titanium mixed powder according to the present invention, since the titanium mixed powder is stored in an airtight container maintained at a vacuum level of 10-6 to 20 Torr, the oxygen concentration of the titanium mixed powder remains constant for a long period of time. There is no significant increase in the mechanical properties of titanium alloys produced using this titanium mixed powder as a raw material.
【図１】本発明の１実施例のチタン混合粉末の保管方法
に使用する保管容器の縦断面図である。FIG. 1 is a longitudinal sectional view of a storage container used in a method for storing titanium mixed powder according to an embodiment of the present invention.
【図２】保管時間とチタン混合粉末の酸素濃度との関係
を真空度をパラメターとして示すグラフである。FIG. 2 is a graph showing the relationship between storage time and oxygen concentration of the titanium mixed powder using the degree of vacuum as a parameter.
【図３】焼結チタン合金をプレス成形法で製造する場合
の工程図である。FIG. 3 is a process diagram for manufacturing a sintered titanium alloy by a press molding method.
【図４】従来のチタン混合粉末の保管方法に使用する保
管容器の縦断面図である。FIG. 4 is a longitudinal cross-sectional view of a storage container used in a conventional method for storing mixed titanium powder.
【図５】チタン混合粉末の酸素濃度と衝撃値との関係を
示すグラフである。FIG. 5 is a graph showing the relationship between oxygen concentration and impact value of titanium mixed powder.
１ 缶体 ２ 蓋 ３ シ−ルバンド ４ シ−ルリング ５ 圧力計 ６ 導管 １０ 気密容器 １１ 棚段 １２ 支柱 １３ ビニ−ル袋 １４ チタン混合粉末 1 Can body 2 Lid 3 Seal band 4 Seal ring 5 Pressure gauge 6 Conduit 10 Airtight container 11 Shelf 12 Pillar 13 Plastic bag 14 Titanium mixed powder
Claims (1)
製造する際に使用するチタン混合粉末の保管方法におい
て、内部圧力が１０−６〜２０Ｔｏｒｒの真空状態に保
持された気密容器中に、チタン混合粉末を保管すること
を特徴とするチタン混合粉末の保管方法。Claim 1: In a method for storing a mixed titanium powder used when producing a sintered titanium alloy by a raw powder mixing method, titanium is stored in an airtight container maintained in a vacuum state with an internal pressure of 10-6 to 20 Torr. A method for storing mixed powder of titanium, characterized by storing the mixed powder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3077514A JPH04218601A (en) | 1990-04-13 | 1991-04-10 | Method for storing titanium powder mixture |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9857890 | 1990-04-13 | ||
| JP2-98578 | 1990-04-13 | ||
| JP3077514A JPH04218601A (en) | 1990-04-13 | 1991-04-10 | Method for storing titanium powder mixture |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04218601A true JPH04218601A (en) | 1992-08-10 |
Family
ID=26418589
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3077514A Pending JPH04218601A (en) | 1990-04-13 | 1991-04-10 | Method for storing titanium powder mixture |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04218601A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011178646A (en) * | 2010-02-26 | 2011-09-15 | Yukichi Horioka | Vacuum storage method and apparatus for crystal material |
| WO2013027299A1 (en) * | 2011-08-25 | 2013-02-28 | 三菱マテリアルテクノ株式会社 | Vacuum storage method and device for crystalline material |
-
1991
- 1991-04-10 JP JP3077514A patent/JPH04218601A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011178646A (en) * | 2010-02-26 | 2011-09-15 | Yukichi Horioka | Vacuum storage method and apparatus for crystal material |
| WO2013027299A1 (en) * | 2011-08-25 | 2013-02-28 | 三菱マテリアルテクノ株式会社 | Vacuum storage method and device for crystalline material |
| US9250014B2 (en) | 2011-08-25 | 2016-02-02 | Mitsubishi Materials Techno Corporation | Vacuum storage method and device for crystalline material |
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