JPH04293701A - Production of soft magnetic powder having high saturation magnetic flux density - Google Patents
Production of soft magnetic powder having high saturation magnetic flux densityInfo
- Publication number
- JPH04293701A JPH04293701A JP3083344A JP8334491A JPH04293701A JP H04293701 A JPH04293701 A JP H04293701A JP 3083344 A JP3083344 A JP 3083344A JP 8334491 A JP8334491 A JP 8334491A JP H04293701 A JPH04293701 A JP H04293701A
- Authority
- JP
- Japan
- Prior art keywords
- powder
- phase
- flux density
- magnetic flux
- soft magnetic
- 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.)
- Withdrawn
Links
- 230000004907 flux Effects 0.000 title claims abstract description 21
- 239000006247 magnetic powder Substances 0.000 title claims abstract description 18
- 238000004519 manufacturing process Methods 0.000 title claims description 5
- 239000000843 powder Substances 0.000 claims abstract description 26
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 22
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 13
- 229910000920 Fe16N2 Inorganic materials 0.000 claims abstract description 11
- 229910000859 α-Fe Inorganic materials 0.000 claims abstract description 7
- 238000010298 pulverizing process Methods 0.000 claims description 4
- 239000007789 gas Substances 0.000 abstract description 4
- 238000005275 alloying Methods 0.000 abstract description 2
- 238000009792 diffusion process Methods 0.000 abstract description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract 6
- 229910052742 iron Inorganic materials 0.000 abstract 1
- 239000002131 composite material Substances 0.000 description 9
- 238000000034 method Methods 0.000 description 8
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 4
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- 229920005989 resin Polymers 0.000 description 4
- 239000011347 resin Substances 0.000 description 4
- 239000002245 particle Substances 0.000 description 3
- 229910021529 ammonia Inorganic materials 0.000 description 2
- 238000012733 comparative method Methods 0.000 description 2
- 239000000470 constituent Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000003822 epoxy resin Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000005121 nitriding Methods 0.000 description 2
- 229920000647 polyepoxide Polymers 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000000700 radioactive tracer Substances 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000004098 selected area electron diffraction Methods 0.000 description 1
- 239000013585 weight reducing agent Substances 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
- H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
- H01F1/147—Alloys characterised by their composition
Abstract
Description
【０００１】0001
【産業上の利用分野】この発明は、高い飽和磁束密度を
有する軟磁性粉末の製造法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a method for producing soft magnetic powder having a high saturation magnetic flux density.
【０００２】0002
【従来の技術】従来、モーターやトランスなどの磁心、
さらに磁気シールドなどの樹脂結合軟磁性複合部材が、
純Ｆｅ粉末などの軟磁性粉末に、所定割合のエポキシ樹
脂などの樹脂結合剤を配合し、混合した後、所定形状の
圧粉体に加圧成形し、この圧粉体に樹脂硬化処理を施す
ことにより製造されることは良く知られるところである
。[Prior Art] Conventionally, magnetic cores of motors, transformers, etc.
Furthermore, resin bonded soft magnetic composite members such as magnetic shields,
A predetermined proportion of a resin binder such as an epoxy resin is blended into a soft magnetic powder such as pure Fe powder, and after mixing, it is pressure-molded into a powder compact of a predetermined shape, and this compact is subjected to a resin hardening treatment. It is well known that it is manufactured by
【０００３】0003
【発明が解決しようとする課題】一方、近年の各種電気
電子機器の高性能化および軽量化はめざましく、これに
伴ない、これらの磁性部材として用いられる各種樹脂結
合軟磁性複合部材にも特に飽和磁束密度の向上が要求さ
れるが、従来の軟磁性複合部材においては、これを構成
する軟磁性粉末の飽和磁束密度が十分でないために、こ
れらの要求に満足に対応することができないのが現状で
ある。[Problems to be Solved by the Invention] On the other hand, in recent years, the performance and weight reduction of various electrical and electronic devices have been remarkable. Improvements in magnetic flux density are required, but conventional soft magnetic composite members cannot satisfactorily meet these demands because the saturation magnetic flux density of the soft magnetic powder that constitutes them is insufficient. It is.
【０００４】0004
【課題を解決するための手段】そこで、本発明者等は、
上述のような観点から、高い飽和磁束密度を有する軟磁
性粉末を製造すべく研究を行なった結果、まず、例えば
純度：１００メッシュ以下のアトマイズ純Ｆｅ粉末など
の純Ｆｅ粉末に、例えばアンモニア気流中、温度：５７
０℃で窒化処理を施して、主体組織がα−Ｆｅ相とε−
ＦｅｘＮ相（ｘ＝２〜３）からなり、かつ窒素：５〜１
５原子％を含有する窒化処理Ｆｅ粉末を形成し、この窒
化処理Ｆｅ粉末に、粉砕ボールの高い衝突エネルギーが
粉末に付与されるアトライターミルや遊星ボールミルな
どの高エネルギー粉砕機を用いて、粉砕混合処理を施す
と、前記窒化処理Ｆｅ粉末には、これの粉砕・薄片化、
および薄片の冷間圧接あるいは薄片の母粉末へのたたみ
込みが起り、この結果α−Ｆｅ相およびε−ＦｅｘＮ相
（ｘ＝２〜３）の主要構成相の超微細混合と同時に、窒
素拡散による合金化が進行して飽和磁束密度の高い準安
定Ｆｅ１６Ｎ２ 相が形成されるようになり、上記準安
定Ｆｅ１６Ｎ２ 相を粉末全体に占める割合で２０容量
％以上含有する高エネルギー粉砕処理粉末は、高い飽和
磁束密度を示し、かつこの軟磁性粉末を樹脂結合軟磁性
複合部材の製造に用いた場合にも、製造された軟磁性複
合部材は同様に高い飽和磁束密度を示すようになるとい
う研究結果を得たのである。[Means for solving the problem] Therefore, the present inventors
From the above-mentioned point of view, as a result of conducting research to produce soft magnetic powder with a high saturation magnetic flux density, first, pure Fe powder such as atomized pure Fe powder with a purity of 100 mesh or less was heated in a stream of ammonia, for example. , temperature: 57
After nitriding at 0℃, the main structure is α-Fe phase and ε-
Consisting of FexN phase (x = 2 to 3), and nitrogen: 5 to 1
A nitrided Fe powder containing 5 at. When subjected to the mixing treatment, the nitrided Fe powder undergoes pulverization and flaking,
and cold welding of the flakes or folding of the flakes into the base powder, resulting in ultrafine mixing of the main constituent phases of α-Fe phase and ε-FexN phase (x = 2 to 3), and at the same time due to nitrogen diffusion. As alloying progresses, a metastable Fe16N2 phase with a high saturation magnetic flux density is formed, and a high-energy pulverized powder containing 20% by volume or more of the above-mentioned metastable Fe16N2 phase in the entire powder has a highly saturated Research results have shown that when this soft magnetic powder is used to manufacture resin-bonded soft magnetic composite members, the manufactured soft magnetic composite members also exhibit high saturation magnetic flux density. It was.
【０００５】この発明は、上記の研究結果にもとづいて
なされたものであって、α−Ｆｅ相とε−ＦｅｘＮ相（
ｘ＝２〜３）を主体組織とする窒素：５〜１５原子％含
有の窒化処理Ｆｅ粉末に、高エネルギー粉砕処理を施し
て、前記窒化処理粉末中に全体に占める割合で２０容量
％以上の準安定Ｆｅ１６Ｎ２ 相を形成することにより
高い飽和磁束密度を有する軟磁性粉末を製造する方法に
特徴を有するものである。[0005] This invention was made based on the above research results, and consists of α-Fe phase and ε-FexN phase (
A nitrided Fe powder containing 5 to 15 atomic % of nitrogen having a main structure of The present invention is characterized by a method of producing soft magnetic powder having a high saturation magnetic flux density by forming a metastable Fe16N2 phase.
【０００６】なお、この発明の方法において、窒化処理
Ｆｅ粉末の窒素含有量を５〜１５原子％と限定したのは
、その含有量が５原子％未満でも、また１５原子％を越
えても次工程の高エネルギー粉砕処理工程でのＦｅ１６
Ｎ２相の形成が困難となり、粉末全体に占める割合で２
０容量％以上のＦｅ１６Ｎ２ 相を形成することができ
ないという理由によるものであり、また高エネルギー粉
砕処理粉末中の準安定Ｆｅ１６Ｎ２ 相の含有量を２０
容量％以上としたのは、その割合が２０容量％未満では
所望の高い飽和磁束密度を確保することができないとい
う理由からである。[0006] In the method of the present invention, the nitrogen content of the nitrided Fe powder is limited to 5 to 15 at%, because even if the content is less than 5 at% or exceeds 15 at%, the following Fe16 in the high-energy pulverization process of the process
It becomes difficult to form N2 phase, and the proportion of N2 phase in the whole powder decreases to 2.
This is because it is not possible to form a Fe16N2 phase of 0% or more by volume, and the content of the metastable Fe16N2 phase in the high-energy pulverized powder is reduced to 20% by volume.
The reason why the ratio is set to be at least 20% by volume is that if the ratio is less than 20% by volume, a desired high saturation magnetic flux density cannot be secured.
【０００７】[0007]
【実施例】つぎに、この発明の方法を実施例により具体
的に説明する。[Examples] Next, the method of the present invention will be explained in detail with reference to Examples.
【０００８】粒度：１００メッシュ以下のアトマイズ純
Ｆｅ粉末に、アンモニア気流中、温度：５７０℃に２〜
１００時間の範囲内の所定時間保持の条件で窒化処理を
施して、主要構成相がいずれもα−Ｆｅ相とε−Ｆｅｘ
Ｎ相（ｘ＝２〜３）からなり、かつ表１に示される窒素
含有量の窒化処理Ｆｅ粉末を形成し、ついでこれらの窒
化処理Ｆｅ粉末：１５ｇを、それぞれ容器がステンレス
鋼製の遊星ボールミルに、直径：１１ｍｍのステンレス
鋼製ボール１１個と一緒に装入し、容器内を真空引きし
てから高純度Ｎ２ ガスを導入して雰囲気をＮ２ ガス
雰囲気とした状態で、容器を３００ｒｐｍ の公転速度
で回転し、２０時間の高エネルギー粉砕処理を行なうこ
とにより本発明法１〜３、並びに窒化処理Ｆｅ粉末の窒
素含有量がこの発明の範囲から外れた比較法１，２をそ
れぞれ実施し、粒度：１５０メッシュ以下（２５〜３５
μｍの範囲内の所定の平均粒径）を有する軟磁性粉末を
製造した。[0008] Atomized pure Fe powder with a particle size of 100 mesh or less was heated to 570°C in an ammonia stream for 2 to 30 minutes.
Nitriding treatment is performed under conditions of holding for a predetermined time within the range of 100 hours, and the main constituent phases are α-Fe phase and ε-Fex.
Nitrided Fe powder consisting of N phase (x = 2 to 3) and having the nitrogen content shown in Table 1 was formed, and then 15 g of these nitrided Fe powders were placed in a planetary ball mill with a container made of stainless steel. The container was charged together with 11 stainless steel balls with a diameter of 11 mm, and after the inside of the container was evacuated, high-purity N2 gas was introduced to create an N2 gas atmosphere, and the container was rotated at 300 rpm. Methods 1 to 3 of the present invention and comparative methods 1 and 2 in which the nitrogen content of the nitrided Fe powder was out of the range of the present invention were carried out by rotating at high speed and performing high-energy pulverization treatment for 20 hours, Particle size: 150 mesh or less (25-35
A soft magnetic powder having a predetermined average particle size in the range of μm was produced.
【０００９】[0009]
【表１】[Table 1]
【００１０】この結果得られた軟磁性粉末について、Ｆ
ｅ１６Ｎ２相の含有割合および飽和磁束密度を測定した
。Regarding the soft magnetic powder obtained as a result, F
The content ratio of e16N2 phase and the saturation magnetic flux density were measured.
【００１１】Ｆｅ１６Ｎ２ 相の含有割合は、２００ｋ
Ｖ透過電子顕微鏡を用いて制限視野電子線回折を行ない
、この結果の回折パターンの中のＦｅ１６Ｎ２ 相の反
射を用いて暗視野像を結像して、写真撮影し、この写真
からＦｅ１６Ｎ２ 相の体積分率を算出することにより
求めた。[0011] The content ratio of Fe16N2 phase is 200k
Selected area electron diffraction was performed using a V transmission electron microscope, and a dark field image was formed using the reflection of the Fe16N2 phase in the resulting diffraction pattern, and a photograph was taken. From this photograph, the volume of the Fe16N2 phase was determined. It was determined by calculating the fraction.
【００１２】また飽和磁束密度は、振動試料型磁力計を
用い、１０ＫＯｅの磁場を印加して測定した。The saturation magnetic flux density was measured using a vibrating sample magnetometer and applying a magnetic field of 10 KOe.
【００１３】さらに、これらの軟磁性粉末に、それぞれ
２重量％のエポキシ樹脂を加え、アセトン中で混練し、
アセトンを蒸発除去した後、５ ｔｏｎ／ｃｍ２ の圧
力で外径：４０ｍｍ×内径：２０ｍｍ×厚さ：１０ｍｍ
の寸法をもったリング状圧粉体にプレス成形し、この圧
粉体に、温度：２００℃に１時間保持の条件で樹脂硬化
処理を施すことにより軟磁性複合部材を製造した。Furthermore, 2% by weight of epoxy resin was added to each of these soft magnetic powders, and the mixture was kneaded in acetone.
After removing acetone by evaporation, the outer diameter: 40 mm x inner diameter: 20 mm x thickness: 10 mm was prepared at a pressure of 5 ton/cm2.
A soft magnetic composite member was manufactured by press-molding the powder into a ring-shaped green compact having dimensions of , and subjecting the green compact to a resin curing treatment at a temperature of 200° C. for 1 hour.
【００１４】これらの軟磁性複合部材の飽和磁束密度を
、直流Ｂ−Ｈカーブトレーサーを用い、５０・Ｏｅの磁
界を印加して測定した。これらの測定結果を表１に示し
た。The saturation magnetic flux density of these soft magnetic composite members was measured by applying a magnetic field of 50·Oe using a DC B-H curve tracer. The results of these measurements are shown in Table 1.
【００１５】なお、表１には、代表的軟磁性粉末として
知られている純Ｆｅ粉末の同一条件での測定結果も示し
た。Table 1 also shows the measurement results of pure Fe powder, which is known as a typical soft magnetic powder, under the same conditions.
【００１６】[0016]
【発明の効果】表１に示される結果から、本発明法１〜
３で製造された軟磁性粉末は、純Ｆｅ粉末に比して一段
と高い飽和磁束密度を示し、かつこれを用いて製造した
軟磁性複合部材も高い飽和磁束密度を示し、一方比較法
１，２で製造された軟磁性粉末に見られるように、窒化
処理Ｆｅ粉末中の窒素含有量がこの発明の範囲から外れ
ると、いずれの場合も高エネルギー粉砕処理によって２
０容量％以上の準安定Ｆｅ１６Ｎ２ 相を形成すること
ができないので、この結果の軟磁性粉末並びにこれを用
いて製造した軟磁性複合部材は低い飽和磁束密度しか示
さないことが明らかである。Effects of the invention From the results shown in Table 1, it can be seen that methods 1 to 1 of the present invention
The soft magnetic powder produced in Comparative Methods 1 and 2 showed a much higher saturation magnetic flux density than pure Fe powder, and the soft magnetic composite member produced using it also showed a higher saturation magnetic flux density. When the nitrogen content in the nitrided Fe powder falls outside the scope of this invention, as seen in the soft magnetic powder produced by
It is clear that since it is not possible to form more than 0% by volume of the metastable Fe16N2 phase, the resulting soft magnetic powder as well as the soft magnetic composite member manufactured using the same exhibit only a low saturation magnetic flux density.
【００１７】上述のように、この発明の方法によれば、
高い飽和磁束密度を有する軟磁性粉末を製造することが
でき、したがってこの軟磁性粉末を用いれば高い飽和磁
束密度を有する軟磁性複合部材の製造も可能であって、
これが組込まれる各種電気電子機器の高性能化および軽
量化に寄与するところ大なるものがあるなど工業上有用
な効果がもたらされるのである。As mentioned above, according to the method of the present invention,
A soft magnetic powder having a high saturation magnetic flux density can be manufactured, and therefore, by using this soft magnetic powder, it is also possible to manufacture a soft magnetic composite member having a high saturation magnetic flux density,
It brings about industrially useful effects, such as greatly contributing to higher performance and lighter weight of various electrical and electronic devices in which it is incorporated.
Claims (1)
〜３）を主体組織とする窒素：５〜１５原子％含有の窒
化処理Ｆｅ粉末に、高エネルギー粉砕処理を施して、前
記窒化処理Ｆｅ粉末中に全体に占める割合で２０容量％
以上の準安定Ｆｅ１６Ｎ２ 相を形成することを特徴と
する高い飽和磁束密度を有する軟磁性粉末の製造法。Claim 1: α-Fe phase and ε-FexN phase (x=2
~3) Nitrogen: 5 to 15 atomic % containing nitrogen is subjected to high-energy pulverization treatment to form a nitrided Fe powder with a proportion of 20 volume % to the total in the nitrided Fe powder.
A method for producing soft magnetic powder having a high saturation magnetic flux density, characterized by forming the above metastable Fe16N2 phase.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3083344A JPH04293701A (en) | 1991-03-22 | 1991-03-22 | Production of soft magnetic powder having high saturation magnetic flux density |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3083344A JPH04293701A (en) | 1991-03-22 | 1991-03-22 | Production of soft magnetic powder having high saturation magnetic flux density |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04293701A true JPH04293701A (en) | 1992-10-19 |
Family
ID=13799823
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3083344A Withdrawn JPH04293701A (en) | 1991-03-22 | 1991-03-22 | Production of soft magnetic powder having high saturation magnetic flux density |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04293701A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20050111457A (en) * | 2004-05-21 | 2005-11-25 | 박종덕 | The fe-based nano-alloy powders and the method there of |
| CN103268799A (en) * | 2013-05-02 | 2013-08-28 | 南昌大学 | Iron nitrogen boron nano-crystalline soft magnetic material and preparation method thereof |
-
1991
- 1991-03-22 JP JP3083344A patent/JPH04293701A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20050111457A (en) * | 2004-05-21 | 2005-11-25 | 박종덕 | The fe-based nano-alloy powders and the method there of |
| CN103268799A (en) * | 2013-05-02 | 2013-08-28 | 南昌大学 | Iron nitrogen boron nano-crystalline soft magnetic material and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9378876B2 (en) | Ferromagnetic particles and process for producing the same, and anisotropic magnet, bonded magnet and compacted magnet | |
| US20150248956A1 (en) | Rare-earth-iron-based alloy material | |
| WO2012161189A1 (en) | Rare earth-iron-nitrogen system alloy material, method for producing rare earth-iron-nitrogen system alloy material, rare earth-iron system alloy material, and method for producing rare earth-iron system alloy material | |
| JPH0974006A (en) | Magnetic material and bonded magnet | |
| JPH06346101A (en) | Magnetically anisotropic powder and its production | |
| EP3379550A1 (en) | Method for producing rare earth magnet and rare earth magnet | |
| JP2000086685A (en) | Production of iron carbonyl silicide, and iron carbonyl silicide | |
| JPH09190909A (en) | Manufacture of r-t-n permanent magnet powder and of anisotropic bond magnet | |
| JPH08191006A (en) | Magnetic material | |
| JPH05222483A (en) | Production of iron nitride based high density sintered compact | |
| Jurczyk et al. | Application of high energy ball milling to the production of magnetic powders from NdFeB-type alloys | |
| JPH04293701A (en) | Production of soft magnetic powder having high saturation magnetic flux density | |
| JPH04293702A (en) | Production of soft magnetic powder low in coercive force | |
| JPH0766021A (en) | Permanent magnet | |
| JPH0590018A (en) | Manufacture of magnetic powder | |
| JP2016044352A (en) | Method for producing powder for magnet, and method for producing rare earth magnet | |
| JP2016100519A (en) | Production method of magnetic powder, production method of dust magnet member, and dust magnet member | |
| JPH05226130A (en) | Manufacture of smfen magnet powder | |
| JPH07118702A (en) | Production of fe-n soft magnetic powder having high saturation magnetic flux density | |
| JPH04371505A (en) | Production of soft magnetic powder having high saturation magnetic flux density | |
| JP6331982B2 (en) | Magnet molded body, magnetic member, method for manufacturing magnet molded body, and method for manufacturing magnetic member | |
| JPH07118703A (en) | Production of fe-n soft magnetic powder having high saturation magnetic flux density | |
| JP3209291B2 (en) | Magnetic material and its manufacturing method | |
| JP2926161B2 (en) | Manufacturing method of permanent magnet | |
| JPH059503A (en) | Production of fe-co soft magnetic powder |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Application deemed to be withdrawn because no request for examination was validly filed |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 19980514 |