JPH0454741B2

JPH0454741B2 -

Info

Publication number: JPH0454741B2
Application number: JP61214101A
Authority: JP
Inventors: Wataru Yamagishi; Munetaka Takeuchi; Tsutomu Iikawa
Original assignee: Fujitsu Ltd
Current assignee: Fujitsu Ltd
Priority date: 1986-09-12
Filing date: 1986-09-12
Publication date: 1992-09-01
Also published as: JPS6372852A

Description

[Detailed description of the invention]

〔概要〕軟質磁性材料として最大の飽和磁束密度を有す
るFe−50％Co合金の磁気特性を実用上許容出来
る範囲に保持しつつ、その難加工性、特に被削性
を向上させるために第三成分としてマンガンを添
加していわゆる粉末冶金法で製造したFe−Co焼
結合金の製造方法。〔産業上の利用分野〕本発明は、軟質磁性材料として有用な鉄（Fe）
−コバルト（Co）焼結合金の製造方法に関し、
更に詳しくは従来のFe−Co合金の欠点である難
加工性、特に被削性を、Fe−Co合金の磁気特性
を実用上許容出来る範囲に保持しつつ、改良した
Fe−Co軟質磁性材料用焼結合金の製造方法に関
する。〔従来の技術〕 Fe−Co合金は軟質磁性材料中で最も飽和磁束
密度が高い合金材料として溶解鋳造によつて製造
されたものが実用に供されているが、冷間加工
性、特に被削性（例えば切削性、施削性、研削性
など）に乏しいという欠点があつた。かかる欠点
を解決する目的でFe−50％Co溶製材合金にバナ
ジウム２％を添加して冷間加工性を改良した2V
−パーメンジユールが知られている。更に本発明
者らは二次加工を必要としない軟質磁性材料とし
て先きに粉末冶金法で製造したFe−Co焼結合金
を提案した（特願昭60−186575号など参照）。〔発明が解決しようとする問題点〕前述の如く、従来のFe−Co溶製材合金は冷間
加工性に劣り、これにバナジウムを２％添加して
加工性を改良したFe−Co合金も知られているが、
加工性、特に被削性に未だ劣り実用上問題があつ
た。また、前述の如く、本発明者らはFe−Co合
金を粉末冶金法で製造することを提案したが、こ
のFe−Co合金も二次加工を必要とする場合には、
被削性が必ずしも充分ではなく実用上その改良が
必要である。〔問題点を解決するための手段〕本発明に従えば、コバルト45〜55重量％、マン
ガン0.01〜2.5重量％及び残部の鉄の組成を有す
る混合粉末から粉末冶金法で製造することを特徴
とする軟質磁性材料用鉄−コバルト焼結合金の製
造方法が提供される。〔作用〕本発明に従つたFe−Co焼結合金は、前述の如
く、コバルト（Co）45〜55重量％、好ましくは
48〜52重量％、マンガン（Mn）、0.01〜2.5重量
％、好ましくは1.5〜2.5重量％と残部鉄（Fe）か
ら成る組成を有し、例えば鉄粉、コバルト粉、マ
ンガン粉、鉄−コバルト合金粉、鉄−マンガン合
金粉などを適宜混合した混合粉を原料とし、これ
を粉末冶金法によつて焼結することにより製造す
ることができる。焼結合金中のコバルト含量が45
重量％未満であつたり、又は55重量％を超えたり
すると、透磁率が低下するので好ましくない。本発明に従えば、前記した如く、Fe−Co焼結
合金中に少量のMnを含有せしめてFe−Co焼結合
金の被削性を著しく改良することができるが、こ
れはMnには脱酸作用があり、焼結時の酸化を防
止する作用を有しているためと思われる。Fe−
Co焼結合金中のMn含量が0.01重量％未満では、
所望の被削性の改良効果が得られず、逆にMn含
量が３重量％を超えると得られるFe−Co焼結合
金の磁気的性質が劣化して実用的でなくなるので
好ましくない。なお、Mnに代えてバナジウムを
用いた場合には溶製材合金の場合と違つて得られ
るFe−Co焼結合金の加工性は改良されず、アル
ミニウムやクロムなどの場合には磁気特性が劣化
して所望の磁気材料は得られなかつた。本発明に従つたMn含有Fe−Co焼結合金は前述
の如く粉末冶金法によつて製造することができ
る。粉末冶金法は常法によつて行なうことがで
き、例えば前記したFe、Co及びMnを含む混合粉
末を以下のようにして焼結することができる。即ち、例えばFe、Co及びMnの粉末を常法に従
つて混合し、例えば３〜5t／cm²程度の圧力で圧粉
成形し、150〜550℃の温度に加熱して潤滑剤を除
去する。次に、得られた混合成形粉末を600〜850
℃程度の温度で仮焼結し、更に５〜8t／cm²程度の
圧力で再圧縮した後、温度1300〜1450℃で焼結す
ることによつて所望の鉄−コバルト焼結合金を得
ることができる。〔実施例〕以下に本発明の実施例を説明するが、本発明の
技術的範囲をこれらの実施例に限定するものでな
いことはいうまでもない。なお、以下の実施例に
おいて「％」は特にことわらない限り「重量％」
を示す。実施例１及び比較例１原料粉として、80％Fe−20％Co合金粉
（325mesh以下）、Co粉（400mesh以下）および25
％Fe−75％Mn合金粉（250mesh以下）を用意
し、これらを２％Mn−49％Fe−49％Coとなるよ
うに秤量し、さらに潤滑剤としてステアリン酸亜
鉛0.75％を加えて混合した。これらの混合粉を
392MPa（4t／cm²）の成形圧力で外径45mm×内径
35mm×厚さ７mmの形状に圧粉成形した。その後、
温度400℃において圧粉体より前記潤滑剤を除去
し、温度600〜750℃において１時間水素雰囲気に
て予備焼結し、さらに588MPa（6t／cm²）の圧力
で再圧縮成形した。最後にこの予備焼結品をプツ
シヤー型水素雰囲気炉にて1300〜1400℃にて１時
間焼結した。得られた焼結合金の磁気的性質及び加工性を測
定した。また対照又は比較材料として、Mnを配
合しない以外は実施例１と同様にして製造した
Fe50％−Co50％焼結合金（比較例１）、Mn2％を
含む溶製材合金（２％Mn−49％Fe−49％Co）
（比較例２）並びに市販の2V−パーメンジユール
（溶製材２％Ｖ−49％Fe−49％Co合金）（対照例
１）、及び炭素鋼（S15C）（対照例２）について
も同様に評価した。結果は第１表に示した通りである。 [Summary] In order to maintain the magnetic properties of the Fe-50%Co alloy, which has the highest saturation magnetic flux density among soft magnetic materials, within a practically acceptable range, we developed a third method to improve its difficult-to-process properties, especially its machinability. A method for producing a Fe-Co sintered alloy manufactured by a so-called powder metallurgy method by adding manganese as a component. [Industrial Application Field] The present invention is directed to iron (Fe), which is useful as a soft magnetic material.
- Regarding the method for producing cobalt (Co) sintered alloy,
More specifically, we have improved the difficulty of machining, especially machinability, which is a drawback of conventional Fe-Co alloys, while maintaining the magnetic properties of Fe-Co alloys within a practically acceptable range.
The present invention relates to a method for producing a sintered alloy for Fe-Co soft magnetic materials. [Prior art] Fe-Co alloys are manufactured by melting and casting as alloy materials with the highest saturation magnetic flux density among soft magnetic materials, but they have poor cold workability, especially in machining. The disadvantage was that it had poor properties (for example, machinability, machinability, grindability, etc.). In order to solve these drawbacks, 2V was created by adding 2% vanadium to Fe-50%Co ingot material alloy to improve cold workability.
-Permendial is known. Furthermore, the present inventors have previously proposed an Fe--Co sintered alloy manufactured by powder metallurgy as a soft magnetic material that does not require secondary processing (see Japanese Patent Application No. 186575/1986, etc.). [Problems to be solved by the invention] As mentioned above, the conventional Fe-Co melted lumber alloy has poor cold workability, and an Fe-Co alloy with improved workability by adding 2% vanadium is also known. Although it is
Processability, especially machinability, was still poor and caused problems in practical use. In addition, as mentioned above, the present inventors proposed manufacturing Fe-Co alloy by powder metallurgy, but if this Fe-Co alloy also requires secondary processing,
Machinability is not necessarily sufficient and needs to be improved for practical purposes. [Means for Solving the Problems] According to the present invention, it is produced by a powder metallurgy method from a mixed powder having a composition of 45 to 55% by weight of cobalt, 0.01 to 2.5% by weight of manganese, and the balance iron. A method for manufacturing an iron-cobalt sintered alloy for soft magnetic materials is provided. [Function] As mentioned above, the Fe-Co sintered alloy according to the present invention contains 45 to 55% by weight of cobalt (Co), preferably
48 to 52% by weight, manganese (Mn), 0.01 to 2.5% by weight, preferably 1.5 to 2.5% by weight, and the balance iron (Fe), such as iron powder, cobalt powder, manganese powder, iron-cobalt. It can be manufactured by using a mixed powder obtained by appropriately mixing alloy powder, iron-manganese alloy powder, etc. as a raw material and sintering this by a powder metallurgy method. Cobalt content in sintered alloy is 45
If it is less than 55% by weight or more than 55% by weight, it is not preferable because the magnetic permeability decreases. According to the present invention, as described above, the machinability of the Fe-Co sintered alloy can be significantly improved by incorporating a small amount of Mn into the Fe-Co sintered alloy. This is thought to be because it has acid action and has the effect of preventing oxidation during sintering. Fe−
When the Mn content in the Co sintered alloy is less than 0.01% by weight,
The desired effect of improving machinability cannot be obtained, and conversely, if the Mn content exceeds 3% by weight, the magnetic properties of the obtained Fe--Co sintered alloy deteriorate, making it unpractical, which is not preferable. Note that when vanadium is used instead of Mn, the workability of the resulting Fe-Co sintered alloy is not improved, unlike in the case of ingot alloys, and the magnetic properties deteriorate in the case of aluminum, chromium, etc. However, the desired magnetic material could not be obtained. The Mn-containing Fe--Co sintered alloy according to the present invention can be produced by powder metallurgy as described above. The powder metallurgy method can be carried out by a conventional method, and for example, the above-mentioned mixed powder containing Fe, Co and Mn can be sintered in the following manner. That is, for example, powders of Fe, Co, and Mn are mixed according to a conventional method, compacted at a pressure of about 3 to 5 t/cm ² , and heated to a temperature of 150 to 550°C to remove the lubricant. . Next, the obtained mixed molding powder is 600-850
The desired iron-cobalt sintered alloy is obtained by pre-sintering at a temperature of about 100°C, further compressing at a pressure of about 5 to 8t/ ^cm2 , and then sintering at a temperature of 1300 to 1450°C. Can be done. [Examples] Examples of the present invention will be described below, but it goes without saying that the technical scope of the present invention is not limited to these Examples. In addition, in the following examples, "%" is "weight%" unless otherwise specified.
shows. Example 1 and Comparative Example 1 As raw material powders, 80% Fe-20% Co alloy powder (325 mesh or less), Co powder (400 mesh or less), and 25
%Fe-75%Mn alloy powder (250mesh or less) was prepared, weighed to give 2%Mn-49%Fe-49%Co, and mixed with 0.75% zinc stearate as a lubricant. . These mixed powders
45 mm outer diameter x inner diameter with a molding pressure of 392 MPa (4 t/cm ² )
It was compacted into a shape of 35 mm x 7 mm thick. after that,
The lubricant was removed from the green compact at a temperature of 400°C, pre-sintered in a hydrogen atmosphere at a temperature of 600 to 750°C for 1 hour, and recompression molded at a pressure of 588 MPa (6 t/cm ² ). Finally, this pre-sintered product was sintered in a pusher type hydrogen atmosphere furnace at 1300 to 1400°C for 1 hour. The magnetic properties and workability of the obtained sintered alloy were measured. In addition, as a control or comparative material, a material was manufactured in the same manner as in Example 1 except that Mn was not blended.
Fe50%-Co50% sintered alloy (Comparative Example 1), melted material alloy containing 2% Mn (2%Mn-49%Fe-49%Co)
(Comparative Example 2), commercially available 2V-Permendial (molten material 2% V-49% Fe-49% Co alloy) (Comparative Example 1), and carbon steel (S15C) (Comparative Example 2) were similarly evaluated. . The results are shown in Table 1.

【表】前記実施例１、比較例１及び２並びに対照例１
及び２で得られた材料の加工性を加工後の表面粗
さRmax.で評価した。このときの加工条件は以下の通りであつた。主軸回転数：1000rpm 切削速度：132ｍ／min 送り量：0.1mm／rev 切込量：0.5mm 切削油：不使用評価は、得られた加工後の材料の表面粗さ曲線
を表面粗さ測定機によつて求め、この粗さ曲線か
ら、きずとみなされるような並はずれて大きな山
または谷を除いた凹凸の最大高さを単位μｍで求
め、この数値にＳの記号をつけて表面粗さ
Rmax.を表示した。結果を第２表に示す。[Table] Example 1, Comparative Examples 1 and 2, and Control Example 1
The workability of the material obtained in 2 and 2 was evaluated by the surface roughness Rmax. after processing. The processing conditions at this time were as follows. Spindle rotation speed: 1000rpm Cutting speed: 132m/min Feed rate: 0.1mm/rev Depth of cut: 0.5mm Cutting oil: Not used Evaluation is performed by measuring the surface roughness curve of the obtained processed material using a surface roughness measuring device. From this roughness curve, find the maximum height of the unevenness in μm, excluding abnormally large peaks or valleys that can be considered flaws, and add the symbol S to this value to calculate the surface roughness.
Displayed Rmax. The results are shown in Table 2.

【表】第２表の結果から明らかなように、本発明に係
る実施例１の磁性材料は、実施例１と同じ方法で
Mnを配合せずに得た材料（比較例１）及び実施
例１と同じ組成ではあるが、粉末冶金法ではなく
従来の溶解鋳造法によつて得た材料（比較例２）、
更にはバナジウム２％を含有した市販のFe−Co
合金（対照例１）に比較して加工性に優れ、Co
を含まない一般的な構造用材料（炭素鋼）に匹敵
する加工表面粗さを有している。実施例２第３表に示すように、マンガンの添加量を０％
（無添加）〜3.0％と変化させた以外は実施例１と
同様にして焼結合金を得た。得られた焼結合金の
磁気的性質及び加工性を実施例１と同様にして測
定した。結果を第３表に示す。[Table] As is clear from the results in Table 2, the magnetic material of Example 1 according to the present invention was prepared using the same method as Example 1.
A material obtained without blending Mn (Comparative Example 1), a material having the same composition as Example 1 but obtained by a conventional melt casting method instead of a powder metallurgy method (Comparative Example 2),
Furthermore, commercially available Fe-Co containing 2% vanadium
It has excellent workability compared to the alloy (control example 1), and
It has a machined surface roughness comparable to that of general structural materials (carbon steel) that do not contain carbon steel. Example 2 As shown in Table 3, the amount of manganese added was 0%.
A sintered alloy was obtained in the same manner as in Example 1 except that the content was changed from (no additive) to 3.0%. The magnetic properties and workability of the obtained sintered alloy were measured in the same manner as in Example 1. The results are shown in Table 3.

〔Effect of the invention〕

以上説明したように、本発明に従えば、50％
Fe−50％Co二元焼結合金に比較して磁気特性
（B_4K）が僅かに低下するものの、保持力（Hc）
もやや高くなつたが実用上殆んど問題とならず、
被削性の著しく改良されたMn含有Fe−Co焼結合
金が得られ、実用上極めて有用な軟質磁性材料を
得ることができる。 As explained above, according to the present invention, 50%
Although the magnetic properties (B _4K ) are slightly lower than the Fe-50%Co binary sintered alloy, the coercive force (Hc)
Although it was a little expensive, it hardly caused any problems in practice.
A Mn-containing Fe-Co sintered alloy with significantly improved machinability can be obtained, and a soft magnetic material that is extremely useful in practice can be obtained.

Claims

[Claims]

1 Cobalt 45-55% by weight, manganese 0.01-2.5
1. A method for producing an iron-cobalt sintered alloy for a soft magnetic material, characterized in that it is produced by a powder metallurgy method from a mixed powder having a composition of weight percent and balance iron.