JP2860427B2 - Method for producing sintered body made of amorphous alloy powder - Google Patents
Method for producing sintered body made of amorphous alloy powderInfo
- Publication number
- JP2860427B2 JP2860427B2 JP1229571A JP22957189A JP2860427B2 JP 2860427 B2 JP2860427 B2 JP 2860427B2 JP 1229571 A JP1229571 A JP 1229571A JP 22957189 A JP22957189 A JP 22957189A JP 2860427 B2 JP2860427 B2 JP 2860427B2
- Authority
- JP
- Japan
- Prior art keywords
- amorphous alloy
- sintered body
- alloy powder
- density
- temperature
- 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 - Lifetime
Links
- 229910000808 amorphous metal alloy Inorganic materials 0.000 title claims description 32
- 239000000843 powder Substances 0.000 title claims description 30
- 238000004519 manufacturing process Methods 0.000 title claims description 6
- 230000006835 compression Effects 0.000 claims description 13
- 238000007906 compression Methods 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 10
- 238000001513 hot isostatic pressing Methods 0.000 claims description 8
- 238000000465 moulding Methods 0.000 claims description 7
- 239000011261 inert gas Substances 0.000 claims description 6
- 238000005551 mechanical alloying Methods 0.000 claims description 6
- 238000000748 compression moulding Methods 0.000 claims description 4
- 238000000227 grinding Methods 0.000 claims description 4
- 238000002425 crystallisation Methods 0.000 description 9
- 230000008025 crystallization Effects 0.000 description 9
- 230000000052 comparative effect Effects 0.000 description 5
- 238000002441 X-ray diffraction Methods 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 239000013078 crystal Substances 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 230000001737 promoting effect Effects 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 239000002775 capsule Substances 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 238000007731 hot pressing Methods 0.000 description 1
- 230000002706 hydrostatic effect Effects 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000011812 mixed powder Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000009827 uniform distribution Methods 0.000 description 1
- 238000009849 vacuum degassing Methods 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Landscapes
- Powder Metallurgy (AREA)
Description
【発明の詳細な説明】 産業上の利用分野 この発明は、たとえば電動式パワーステアリング装置
のトルクセンサなどの磁気部品を製造するのに適したア
モルファス合金粉末製焼結体を製造する方法に関する。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a sintered body made of amorphous alloy powder suitable for producing a magnetic component such as a torque sensor of an electric power steering device.
従来の技術と発明の課題 電動式パワーステアリング装置のトルクセンサとし
て、アモルファス合金よりなるものが考えられている。
そして、トルクセンサなどの磁気部品の性能を高めるた
めには、焼結体の空孔率を低く、換言すれば密度を高め
る必要があることが分かっている。焼結体の空孔率が高
いと、磁気特性の温度依存性が高くなり、磁気特性の安
定性を損なう。2. Description of the Related Art As a torque sensor of an electric power steering device, a torque sensor made of an amorphous alloy has been considered.
It has been found that in order to improve the performance of a magnetic component such as a torque sensor, it is necessary to lower the porosity of the sintered body, in other words, to increase the density. If the porosity of the sintered body is high, the temperature dependence of the magnetic properties increases, and the stability of the magnetic properties is impaired.
従来、アモルファス合金粉末製焼結体は、急冷凝固ア
モルファス合金粉末を用いて行われている。しかしなが
ら、急冷凝固アモルファス合金粉末の表面には、酸化皮
膜が形成されているため、高密度の焼結体を製造するの
に適した粉末治金法である熱間静水圧プレス（HIP）に
よっても高密度の焼結体を得ることができないという問
題がある。しかも、HIPを、アモルファス合金が結晶化
しにくい温度で行っても、成形時間が長くなるにつれて
アモルファス合金が結晶化するので、十分高密度の焼結
体を形成するのに必要な時間HIPすることはできず、そ
の結果トルクセンサのような磁気部品をつくるのに適し
た高密度の焼結体を得ることができないという問題があ
る。Conventionally, a sintered body made of an amorphous alloy powder has been used using a rapidly solidified amorphous alloy powder. However, since an oxide film is formed on the surface of the rapidly solidified amorphous alloy powder, hot isostatic pressing (HIP), which is a powder metallurgy method suitable for producing high-density sintered bodies, can also be used. There is a problem that a high-density sintered body cannot be obtained. Moreover, even if the HIP is performed at a temperature at which the amorphous alloy does not easily crystallize, the amorphous alloy crystallizes as the molding time increases, so it is not possible to perform the HIP for the time necessary to form a sufficiently dense sintered body. As a result, there is a problem that a high-density sintered body suitable for manufacturing a magnetic component such as a torque sensor cannot be obtained.
この発明の目的は、上記問題を解決したアモルファス
合金粉末製焼結体の製造方法を提供することにある。An object of the present invention is to provide a method for manufacturing a sintered body made of an amorphous alloy powder, which solves the above problem.
課題を解決するための手段 この発明によるアモルファス合金粉末製焼結体の製造
方法は、 不活性ガス雰囲気中または真空雰囲気中でメカニカル
アロイング法やメカニカルグライディング法により製造
されたアモルファス合金粉末を、熱間静水圧プレスによ
り、アモルファス合金が結晶化しない温度および時間で
圧縮成形し、１次成形品を形成する第１圧縮工程と、１
次成形品を結晶化しない温度で圧縮成形し、１次成形品
の密度を高める第２圧縮工程とよりなるものである。Means for Solving the Problems A method for producing a sintered body made of an amorphous alloy powder according to the present invention comprises: heating an amorphous alloy powder produced by a mechanical alloying method or a mechanical grinding method in an inert gas atmosphere or a vacuum atmosphere; Compression molding at a temperature and for a time during which the amorphous alloy does not crystallize by a hydrostatic pressing during hot pressing to form a primary molded product;
It comprises a second compression step of increasing the density of the primary molded article by compression molding at a temperature at which the next molded article is not crystallized.
上記において、メカニカルアロイング法またはメカニ
カルライディング法は、たとえばボールミルのような装
置を用いて行うものである。すなわち、アモルファス合
金を構成する金属の混合粉末や合金粉末をミルの容器内
に入れ、不活性ガス雰囲気中または真空雰囲気中で、ア
ジテータを所定時間回転させることによりアモルファス
合金粉末を得ることができる。このメカニカルアロイン
グ法やメカニカルグライディング法は、上述のように不
活性ガス雰囲気中または真空雰囲気中で行われるととも
に、破壊と冷間圧接との繰返により粉末表面が常に新表
面となされるので、これらの方法により製造されたアモ
ルファス合金粉末の表面には酸化皮膜が存在しない。In the above, the mechanical alloying method or the mechanical riding method is performed using an apparatus such as a ball mill. That is, an amorphous alloy powder can be obtained by placing a mixed powder or alloy powder of a metal constituting the amorphous alloy in a container of a mill and rotating the agitator for a predetermined time in an inert gas atmosphere or a vacuum atmosphere. Since the mechanical alloying method and the mechanical grinding method are performed in an inert gas atmosphere or a vacuum atmosphere as described above, the powder surface is always formed as a new surface by repetition of destruction and cold welding. There is no oxide film on the surface of the amorphous alloy powder produced by these methods.
第１圧縮工程における成形温度および時間は、予めア
モルファス合金粉末を加圧した場合の成形温度と結晶化
時間との関係を求めておき、その結果から結晶化を起こ
さずに粘性流動を起こす条件を決定する。たとえば、Co
79.5Nb15Zr5.5の場合、上記成形温度と結晶化時間との
関係は、第１図に示すグラフのようになる。第１図のグ
ラフにおいて、直線（Ａ）より下方の部分が、アモルフ
ァスの領域で、上方の部分が結晶の領域である。また、
Ni50Ti50の場合、上記成形温度と結晶化時間との関係
は、第２図に示すグラフのようになる。第２図のグラフ
において、直線（Ｂ）より下方の部分が、アモルファス
の領域で、上方の部分が結晶の領域である。The molding temperature and time in the first compression step are determined in advance by obtaining the relationship between the molding temperature and the crystallization time when the amorphous alloy powder is pressurized, and from the result, the conditions under which viscous flow occurs without crystallization. decide. For example, Co
In the case of 79.5 Nb 15 Zr 5.5 , the relationship between the molding temperature and the crystallization time is as shown in the graph of FIG. In the graph of FIG. 1, a portion below the straight line (A) is an amorphous region, and an upper portion is a crystalline region. Also,
For Ni 50 Ti 50, the relationship between the molding temperature and the crystallization time is as the graph shown in Figure 2. In the graph of FIG. 2, a portion below the straight line (B) is an amorphous region, and an upper portion is a crystalline region.
第２圧縮工程によれば、第１圧縮工程で加えられる応
力以上の応力が加えられ、１次成形体におけるアモルフ
ァス合金の結晶化を促進させることなく、成形体の密度
を高めることができる。According to the second compression step, a stress higher than the stress applied in the first compression step is applied, and the density of the compact can be increased without promoting crystallization of the amorphous alloy in the primary compact.
発明の効果 この発明の方法によれば、不活性ガス雰囲気中または
真空雰囲気中でメカニカルアロイング法やメカニカルグ
ライディング法により製造されたアモルファス合金粉末
を使用するので、該アモルファス合金粉末の表面には酸
化皮膜が存在せず、しかも第１圧縮工程において、HIP
により、上記アモルファス合金粉末に、圧力を等方的に
加えることができるので、均一分布の微細空孔を含む焼
結体からなる１次成形品が得られる。さらに、第１圧縮
工程によればアモルファス合金の結晶化が防止される。
また、第２圧縮工程により、１次成形品を結晶化しない
温度で圧縮成形し、１次成形品の密度を高めるので、ア
モルファス合金の結晶化を促進させることなく、１次成
形品の密度を高めることができる。したがって、この発
明の方法で製造された焼結体は、従来のものよりも高密
度で、しかもアモルファス状態で保たれることとなり、
電動式パワーステアリング装置のトルクセンサのような
磁気部品として高性能のものを製造することが可能とな
る。According to the method of the present invention, an amorphous alloy powder produced by a mechanical alloying method or a mechanical gliding method in an inert gas atmosphere or a vacuum atmosphere is used, so that the surface of the amorphous alloy powder is oxidized. No film exists, and in the first compression step, HIP
As a result, the pressure can be isotropically applied to the amorphous alloy powder, so that a primary molded product made of a sintered body including fine pores having a uniform distribution can be obtained. Further, according to the first compression step, crystallization of the amorphous alloy is prevented.
In the second compression step, the primary molded article is compression molded at a temperature at which the primary molded article is not crystallized, and the density of the primary molded article is increased. Therefore, the density of the primary molded article can be reduced without promoting the crystallization of the amorphous alloy. Can be enhanced. Therefore, the sintered body manufactured by the method of the present invention has a higher density than the conventional one and is kept in an amorphous state.
A high-performance magnetic component such as a torque sensor of an electric power steering device can be manufactured.
実 施 例 以下、この発明の実施例を比較例とともに説明する。Examples Hereinafter, examples of the present invention will be described together with comparative examples.
実施例 平均粒径50μｍのCo粉末と、平均粒径45μｍのNb粉末
と、平均粒径40μｍのZr粉末とを、Co79.5Nb15Zr5.5の
原子量割合となるように混合し、得られた混合粉末を、
メディア撹拌型ボールミルを用いて不活性ガス雰囲気中
または真空雰囲気中でメカニカルアロイング法やメカニ
カルグライディング法によりアモルファス化し、アモル
ファス合金粉末をつくった。ついで、このアモルファス
合金粉末を、Arガス雰囲気中で一端が閉鎖された内径10
mmのCuパイプ内に、パイプ内容積の80％程度充填し、粉
末の充填密度を高めるために150℃で振動を与えた。そ
の後、パイプ内部から真空脱気しながらパイプの他端開
口を閉鎖してカプセル封入した。そして、HIPにより、
昇温速度13℃／分、温度580℃、時間５分、Arガス圧20k
g/mm2の条件でアモルファス合金粉末を圧縮成形し、１
次成形品をつくった（第１圧縮工程）。さらに、１次成
形品をカプセルから取り出し、大気中でかつ室温におい
て圧縮応力が35kgf/mm2となるように圧縮成形し（第２
圧縮工程）、焼結体を製造した。Example Co powder having an average particle size of 50 μm, Nb powder having an average particle size of 45 μm, and Zr powder having an average particle size of 40 μm were mixed so that the atomic weight ratio of Co 79.5 Nb 15 Zr 5.5 was obtained, and the resulting mixture was obtained. The powder,
Using a media stirring type ball mill, an amorphous alloy powder was produced by mechanical alloying or mechanical grinding in an inert gas atmosphere or a vacuum atmosphere. Next, this amorphous alloy powder was placed in an Ar gas atmosphere with an inner diameter of 10 closed at one end.
A 80 mm Cu pipe was filled into a Cu pipe of about 80% of its volume, and vibration was applied at 150 ° C. to increase the packing density of the powder. Thereafter, the other end of the pipe was closed and encapsulated while vacuum degassing from the inside of the pipe. And by HIP,
Heating rate 13 ° C / min, temperature 580 ° C, time 5min, Ar gas pressure 20k
Compression molding of amorphous alloy powder under the condition of g / mm 2
The next molded article was produced (first compression step). Further, the primary molded product is taken out of the capsule and compression-molded in air and at room temperature so that the compressive stress is 35 kgf / mm 2 (second
Compression step) to produce a sintered body.
このようにして製造された焼結体の密度を測定したと
ころ、7.5g/cm3であった。また、この焼結体にディフラ
クトメータを用いてＸ線回折を施したところ、回折図形
は第３図に示すようになり、２θ＝69度付近にCo結晶ら
しき小さなピークが見られるが、ほぼアモルファス状態
が保たれていることがわかる。When the density of the sintered body thus manufactured was measured, it was 7.5 g / cm 3 . When the sintered body was subjected to X-ray diffraction using a diffractometer, the diffraction pattern was as shown in FIG. 3, and a small peak, which is likely to be a Co crystal, was observed at around 2θ = 69 °, but was substantially observed. It can be seen that the amorphous state is maintained.
比較例１ 上記実施例における第１圧縮工程と同様にして焼結体
を製造した。そして、この焼結体の密度を測定したとこ
ろ、7.37g/cm3であった。Comparative Example 1 A sintered body was manufactured in the same manner as in the first compression step in the above example. When the density of this sintered body was measured, it was 7.37 g / cm 3 .
比較例２ 上記実施例と同様にして得られたアモルファス合金粉
末を、上記実施例と同様にしてカプセル封入した。そし
て、HIPにより、温度580℃、時間30分、Arガス圧20kg/m
m2の条件でアモルファス合金粉末を圧縮成形し、焼結体
をつくった。Comparative Example 2 The amorphous alloy powder obtained in the same manner as in the above example was encapsulated in the same manner as in the above example. Then, by HIP, temperature 580 ° C, time 30 minutes, Ar gas pressure 20kg / m
The amorphous alloy powder was compression-molded under the conditions of m 2 to produce a sintered body.
このようにして製造された焼結体の密度を測定したと
ころ、7.5g/cm3であった。また、上記焼結体にディフラ
クトメータを用いてＸ線回折を施したところ、回折図形
は第４図に示すようになり、２θ＝69度付近にCo結晶ら
しき大きなピークが見られ、結晶化されていることがわ
かる。When the density of the sintered body thus manufactured was measured, it was 7.5 g / cm 3 . When the sintered body was subjected to X-ray diffraction using a diffractometer, the diffraction pattern was as shown in FIG. 4, and a large peak, which appeared to be a Co crystal at around 2θ = 69 °, was observed. You can see that it is done.
上記実施例と比較例１とを比べると、製造された焼結
体の密度の差は小さいようではあるが、トルクセンサに
用いた場合には、顕著な性能差としてあらわれる。When comparing the above example with Comparative Example 1, the difference in the density of the manufactured sintered body seems to be small, but when it is used for a torque sensor, it appears as a remarkable performance difference.
第１図はCo79.5Nb15Zr5.5アモルファス合金粉末をHIPに
より加圧するさいの成形温度と結晶化時間との関係を示
すグラフ、第２図はNi50Ti50アモルファス合金粉末をHI
Pにより加圧するさいの成形温度と結晶化時間との関係
を示すグラフ、第３図は実施例で製造された焼結体のＸ
線回折図形、第４図は比較例２で製造された焼結体のＸ
線回折図形である。Figure 1 is Co 79.5 Nb 15 Zr 5.5 amorphous alloy powder a graph showing the relationship between the forming temperature and the crystallization time again to pressurize the HIP, FIG. 2 Ni 50 Ti 50 amorphous alloy powder HI
FIG. 3 is a graph showing the relationship between the molding temperature and the crystallization time when pressurized by P. FIG. 3 shows the X of the sintered body manufactured in the example.
X-ray diffraction pattern, FIG. 4 shows X of the sintered body manufactured in Comparative Example 2.
It is a line diffraction pattern.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 唯根 勉 大阪府大阪市中央区南船場３丁目５番８ 号 光洋精工株式会社内 (56)参考文献 特開 昭63−227730（ＪＰ，Ａ) 特開 昭63−241102（ＪＰ，Ａ) 特開 昭61−195903（ＪＰ，Ａ) 特開 昭62−74032（ＪＰ，Ａ) 特開 昭59−16306（ＪＰ，Ａ) (58)調査した分野(Int.Cl.6，ＤＢ名) B22F 1/00 - 3/26 C22C 1/04 - 1/05,33/02──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Tsutomu Yuine 3-5-8 Minamisenba, Chuo-ku, Osaka-shi, Osaka Inside Koyo Seiko Co., Ltd. (56) References JP-A-63-227730 (JP, A) JP-A-63-241102 (JP, A) JP-A-61-195903 (JP, A) JP-A-62-74032 (JP, A) JP-A-59-16306 (JP, A) (58) Int.Cl. 6 , DB name) B22F 1/00-3/26 C22C 1/04-1 / 05,33 / 02
Claims (1)
メカニカルアロイング法やメカニカルグライディング法
により製造されたアモルファス合金粉末を、熱間静水圧
プレスにより、アモルファス合金が結晶化しない温度お
よび時間で圧縮成形し、１次成形品を形成する第１圧縮
工程と、１次成形品を結晶化しない温度で圧縮成形し、
１次成形品の密度を高める第２圧縮工程とよりなるアモ
ルファス合金粉末製焼結体の製造方法。An amorphous alloy powder produced by a mechanical alloying method or a mechanical grinding method in an inert gas atmosphere or a vacuum atmosphere is compressed by a hot isostatic pressing at a temperature and a time at which the amorphous alloy does not crystallize. Molding, a first compression step of forming a primary molded article, and compression molding at a temperature at which the primary molded article is not crystallized,
A method for producing a sintered body made of an amorphous alloy powder, comprising a second compression step of increasing the density of a primary molded product.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1229571A JP2860427B2 (en) | 1989-09-05 | 1989-09-05 | Method for producing sintered body made of amorphous alloy powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1229571A JP2860427B2 (en) | 1989-09-05 | 1989-09-05 | Method for producing sintered body made of amorphous alloy powder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0394031A JPH0394031A (en) | 1991-04-18 |
| JP2860427B2 true JP2860427B2 (en) | 1999-02-24 |
Family
ID=16894263
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1229571A Expired - Lifetime JP2860427B2 (en) | 1989-09-05 | 1989-09-05 | Method for producing sintered body made of amorphous alloy powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2860427B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107326208A (en) * | 2017-06-20 | 2017-11-07 | 西安理工大学 | A kind of foam magnesium or foam aluminum alloy and preparation method thereof |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010106348A (en) * | 2008-10-31 | 2010-05-13 | Nissan Motor Co Ltd | Metallic glass molded body and method for producing the same |
-
1989
- 1989-09-05 JP JP1229571A patent/JP2860427B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107326208A (en) * | 2017-06-20 | 2017-11-07 | 西安理工大学 | A kind of foam magnesium or foam aluminum alloy and preparation method thereof |
| CN107326208B (en) * | 2017-06-20 | 2019-02-01 | 西安理工大学 | A kind of foam magnesium or foam aluminum alloy and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0394031A (en) | 1991-04-18 |
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