JPS5919163B2 - Method for producing magnetic metal powder - Google Patents

Description

【発明の詳細な説明】 この発明は鉄を主成分とする磁性金属粉末の製造方法に
関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing magnetic metal powder containing iron as a main component.

磁性金属粉末は、一般にα−オキシ水酸化鉄（α−Ｆｅ
０ＯＨ）粉末またはα−ヘマタイト（α−Ｆｅ２Ｏ３）
粉末などを加熱還元することによつて製造され、この製
造の際使用されるα−オキシ水酸化鉄粉末は、通常第一
鉄塩水溶液にアルカリ水溶液を加えて水酸化第一鉄の沈
殿物を生成し、これを空気酸化して得られたものが使用
されている。Magnetic metal powder is generally α-iron oxyhydroxide (α-Fe
0OH) powder or α-hematite (α-Fe2O3)
The α-iron oxyhydroxide powder used in this production is usually produced by adding an alkaline aqueous solution to a ferrous salt aqueous solution to remove the ferrous hydroxide precipitate. The product obtained by air oxidation is used.

ところが前記の方法ではα−オキシ水酸化鉄粉末を製造
する際、中間生成物である水酸化第一鉄の六角板状結晶
の辺縁に沿つてα−オキシ水酸化鉄の結晶が生長するた
め、枝分れ粒子が発生しやすく、また加熱還元時に粉末
粒子間で焼結が起こわやすいためこのα−オキシ水酸化
鉄粉末を還元して得られる磁性金属粉末の磁気特性を充
分に向上できない難点があつた。However, in the above method, when producing α-iron oxyhydroxide powder, α-iron oxyhydroxide crystals grow along the edges of the hexagonal plate-shaped crystals of ferrous hydroxide, which is an intermediate product. Because branched particles are likely to occur and sintering is likely to occur between powder particles during thermal reduction, the magnetic properties of the magnetic metal powder obtained by reducing this α-iron oxyhydroxide powder cannot be sufficiently improved. There was a problem.

このため前記の方法で製造されたα−オキシ水酸化鉄粉
末を還元前にシリコーンオイル等を溶解した溶液に浸漬
して焼結防止処理を行なうことが提案されているが、こ
の方法でぱα−オキシ水酸化鉄の枝分れ粒子の発生を有
効に防止し得ず、従つてこれを還元して得られる磁性金
属粉末の磁気特性も末だ充分に満足できるものではなか
つた。この発明者等はこのようにα−オキシ水酸化鉄粉
末の粒子製造がこれを加熱還元して得られる磁性金属粉
末の磁気特性に大きく影響することに鑑み、α−オキシ
水酸化鉄粉末の製造方法について種々検討を行なつた結
果、第一鉄塩と第一ニッケル塩の混合溶液とアルカリ溶
液とを混合して水酸化第一鉄と水酸化第一ニッケルを共
沈させるか、あるいは第一鉄塩溶液と第一ニッケル塩溶
液の各各にアルカリ溶液を加えて水酸化第一鉄と水酸化
第一ニッケルを別々に沈殿させてから混合した後、この
沈殿物懸濁液に酸素含有ガスを接触させて酸化すると、
枝分れがほとんどなくかつ比較的粒子径が小さくて粒度
分布の均一な針状のニツケル含有α−オキシ水酸化鉄粉
末が得られることを見いだし、これをケイ素化合物｝よ
びアルミニウム化合物から選ばれる一種又は二種の化合
物を含む溶液中に浸漬処理した後、還元ガスで加熱還元
すると一段ど磁気特性に優れたニツケル含有磁性金属粉
末が得られることを見いだしてこの発明をなすに至つた
。For this reason, it has been proposed to perform sintering prevention treatment by immersing the α-iron oxyhydroxide powder produced by the above method in a solution containing silicone oil or the like before reduction. - The generation of branched particles of iron oxyhydroxide could not be effectively prevented, and therefore the magnetic properties of the magnetic metal powder obtained by reducing the iron oxyhydroxide were still not fully satisfactory. In view of the fact that the production of particles of α-iron oxyhydroxide powder greatly affects the magnetic properties of the magnetic metal powder obtained by heating and reducing it, the inventors developed a method for producing α-iron oxyhydroxide powder. As a result of various studies on methods, we decided to coprecipitate ferrous hydroxide and nickel hydroxide by mixing a mixed solution of ferrous salt and nickel salt with an alkaline solution, or to co-precipitate ferrous hydroxide and nickel hydroxide. Ferrous hydroxide and nickel hydroxide are precipitated separately by adding an alkaline solution to each of the iron salt solution and the nickel salt solution, and then mixed, and then an oxygen-containing gas is added to the precipitate suspension. When oxidized by contacting
It has been discovered that an acicular nickel-containing α-iron oxyhydroxide powder with almost no branching, a relatively small particle size, and a uniform particle size distribution can be obtained, and this powder can be used as a compound selected from silicon compounds and aluminum compounds. Alternatively, the present inventors have discovered that a nickel-containing magnetic metal powder with even better magnetic properties can be obtained by immersing the powder in a solution containing two types of compounds and then heating and reducing the powder with a reducing gas.

この発明方法によれば、ニツケル含有α−オキシ水酸化
鉄粉末を生成する際、反応溶液中に第一ニツケル塩を存
在させて水酸化第一鉄と水酸化第一ニツケルを共沈させ
るか、あるいは水酸化第一鉄と水酸化第一ニツケルをそ
れぞれ第一鉄塩又は第一ニツケル塩を存在させた反応溶
液中で別々に沈殿させてから混合した後これを酸素含有
ガスで酸化しているため、生成されるニツケル含有α−
オキシ水酸化鉄の結晶の生長方向がニツケルの存在によ
つて適当に抑制され、従つて粒子の枝分れが有効に防止
されて枝分れがほとんどなくしかも粒子径が比較的小さ
くて粒度分布の均一な針状のニツケル含有α−オキシ水
酸化鉄粉末が得られる。According to the method of this invention, when producing a nickel-containing α-iron oxyhydroxide powder, a nickel salt is present in the reaction solution to co-precipitate ferrous hydroxide and nickel hydroxide, or Alternatively, ferrous hydroxide and nickel hydroxide are precipitated separately in a reaction solution in the presence of a ferrous salt or nickel hydroxide, mixed, and then oxidized with an oxygen-containing gas. Therefore, the nickel-containing α-
The growth direction of iron oxyhydroxide crystals is appropriately suppressed by the presence of nickel, and therefore particle branching is effectively prevented, with almost no branching and the particle size being relatively small, resulting in a particle size distribution. A uniform acicular nickel-containing α-iron oxyhydroxide powder is obtained.

そしてさらにこのニツケル含有α−オキシ水酸化鉄粉末
をケイ素化合物またはアルミニウム化合物もしくは両者
を含む溶液中に浸漬処理した後還元ガスで加熱還元して
いるため、浸漬処理にようニツケル含有α−オキシ水酸
化鉄粉末の表面にケイ素化合物またはアルミニウム化合
物もしくは両者が被着されて還元時に生じやすい粉末粒
子間の焼結が抑制され、従つてニツケル含有α−オキシ
水酸化鉄粉末はそのすぐれた粒子形状を保持したまま還
元され枝分れがほとんどなくかつ比較的粒子径が小さく
て粒度分布の均一な針状のニツケル含有磁性金属鉄粉末
が得られ、磁気特性が一段と向上する。このようにすぐ
れた粒子形状を有するニツケル含有α−オキシ水酸化鉄
粉末は、第一鉄塩と第一ニツケル塩との混合溶液を調製
する際、あるいは第一鉄塩溶液と第一ニツケル塩溶液の
各々にアルカリ溶液を加えて水酸化第一鉄と水酸化第一
ニツケルを別々に沈殿させてから混合調製する際、鉄に
対してニツケルが原子比で０．１％以上となるようにし
たとき生成され、第一ニツケル塩の添加量が増大するに
従つて枝分れ粒子が減少し、粒子径も比較的小さくなつ
て粒度分布もより均一になるが、鉄に対してニツケルが
原子比で１５％を超えると粒子が微細化するのと、水酸
化第一ニツケルが遊離するため第一ニツケル塩の添加量
は鉄に対してニツケルが原子比で０．１〜１５％の範囲
となるようにするのが好ましく、４〜８％の範囲となる
ようにしたとき最も粒子形状のすぐれたニツケル含有α
−オキシ水酸化鉄粉末が得られる。Furthermore, this nickel-containing α-oxyhydroxide powder is immersed in a solution containing a silicon compound, an aluminum compound, or both, and then heated and reduced with a reducing gas. A silicon compound, an aluminum compound, or both are deposited on the surface of the iron powder, suppressing sintering between powder particles that tends to occur during reduction, and therefore the nickel-containing α-iron oxyhydroxide powder maintains its excellent particle shape. The nickel-containing magnetic metal iron powder is reduced as it is, and has almost no branching, has a relatively small particle size, and has a uniform particle size distribution, resulting in an acicular magnetic metal iron powder containing nickel, which further improves the magnetic properties. Nickel-containing α-iron oxyhydroxide powder having such an excellent particle shape can be used when preparing a mixed solution of ferrous salt and nickel salt, or when preparing a mixed solution of ferrous salt and nickel salt. Add an alkaline solution to each to precipitate ferrous hydroxide and nickel hydroxide separately, and then mix and prepare so that the atomic ratio of nickel to iron is 0.1% or more. As the amount of primary nickel salt added increases, the number of branched particles decreases, the particle size becomes relatively small, and the particle size distribution becomes more uniform, but the atomic ratio of nickel to iron decreases. If it exceeds 15%, the particles become finer and nickel hydroxide is liberated, so the amount of nickel salt added is in the range of 0.1 to 15% in terms of atomic ratio of nickel to iron. It is preferable to keep the nickel-containing α in the range of 4 to 8%.
- Iron oxyhydroxide powder is obtained.

第一鉄塩と第一ニツケル塩との混合溶液とアルカリ溶液
とを反応させて水酸化第一鉄と水酸化第一ニツケルを共
沈させる方法としては、通常アルカリ溶液中に攪拌しな
がら第一鉄塩と第一ニツケル塩との混合溶液を混合して
行なわれるが、これとは逆に第一鉄塩と第一ニツケル塩
との混合溶液にアルカリ溶液を混合させてもよい。また
、水酸化第一鉄と水酸化第一ニツケルは別々に沈殿させ
てもよく、この場合は第一鉄塩溶液にアルカリ溶液を加
えて水酸化第一鉄を沈殿生成させる一方、これとは別に
第一ニツケル塩溶液にアルカリ溶液を加えて水酸化第一
ニツケルを沈殿生成させ、これらの水酸化第一鉄懸濁液
と水酸化第一ニツケル懸濁液とを混合することによつて
これら両者を含む沈殿物懸濁液が調製される。第一鉄塩
としては硫酸第一鉄、塩化第一鉄、硝酸第一鉄などが好
適なものとして使用され、また第一ニツケル塩としては
硫酸ニツケル、塩化ニツケル、硝酸ニツケル等が好まし
く用いられる。The method of co-precipitating ferrous hydroxide and nickel hydroxide by reacting a mixed solution of ferrous salt and nickel salt with an alkaline solution is usually to This is carried out by mixing a mixed solution of an iron salt and a nickel salt, but conversely, an alkaline solution may be mixed with a mixed solution of a ferrous salt and a nickel salt. In addition, ferrous hydroxide and nickel hydroxide may be precipitated separately. In this case, an alkaline solution is added to the ferrous salt solution to precipitate ferrous hydroxide. Separately, an alkaline solution is added to the nickel salt solution to precipitate nickel hydroxide, and these ferrous hydroxide suspensions are mixed with the nickel hydroxide suspensions. A precipitate suspension containing both is prepared. As the ferrous salt, ferrous sulfate, ferrous chloride, ferrous nitrate, etc. are preferably used, and as the ferrous nickel salt, nickel sulfate, nickel chloride, nickel nitrate, etc. are preferably used.

アルカリとしては、通常苛性ソーダが用いられ、その好
適な配合量は水酸化第一鉄と水酸化第一ニツケルを共沈
させる場合第一鉄塩と第一ニツケル塩との総量に対して
当量以上で、水酸化第一鉄と水酸化第一ーツケルを別々
に沈殿させる場合には夫々第一鉄塩又は第一ニツケル塩
に対して当量以上である。このように第一鉄塩と第一ニ
ツケル塩との混合溶液とアルカリ溶液とを混合すると水
酸化第一鉄と水酸化第一ーツケルが共沈し、また第一鉄
塩溶液と第一ニツケル塩溶液の各々にアルカリ溶液を加
えて水酸化第一鉄と水酸化第一ニツケルを別々に沈殿さ
せてから混合するとこれらの沈殿物を含む懸濁液が得ら
れ、この沈殿物懸濁液中に酸素含有ガス、たとえば空気
を送り込んで酸化すると枝分れがほとんどなく比較的粒
子径が小さくて粒度分布の均一な針状のニツケル含有α
−オキシ水酸化鉄粉末が得られる。As the alkali, caustic soda is usually used, and when co-precipitating ferrous hydroxide and nickel hydroxide, the preferred amount is equal to or more than the amount equivalent to the total amount of ferrous salt and nickel hydroxide. When ferrous hydroxide and nickel hydroxide are precipitated separately, the amount is equivalent to or more than the ferrous salt or nickel salt, respectively. In this way, when a mixed solution of ferrous salt and nickel salt is mixed with an alkaline solution, ferrous hydroxide and nickel hydroxide co-precipitate, and the ferrous salt solution and nickel salt are co-precipitated. By adding an alkaline solution to each solution to precipitate ferrous hydroxide and nickel hydroxide separately, and then mixing them together, a suspension containing these precipitates is obtained, and in this precipitate suspension, When oxygen-containing gas, such as air, is oxidized, acicular nickel-containing α with almost no branching, relatively small particle size, and uniform particle size distribution is produced.
- Iron oxyhydroxide powder is obtained.

次いで、得られたニツケル含有α−オキシ水酸化鉄粉末
は、還元ガスで加熱還元する前にケイ素化合物またはア
ルミニウム化合物もしくは両者を含む溶液中に浸漬され
て焼結防止処理が施こされる。Next, the obtained nickel-containing α-iron oxyhydroxide powder is subjected to sintering prevention treatment by being immersed in a solution containing a silicon compound or an aluminum compound, or both, before being heated and reduced with a reducing gas.

ここに使用されるケイ素化合物としては、たとえばケイ
酸ナトリウム（ＮＡ４ＳｉＯ４）が好適なものとして使
用され、アルミニウム化合物としては、たとえば硫酸ア
ルミニウム（Ａｌ２（ＳＯ４）３）が好適なものとして
使用される。As the silicon compound used herein, for example, sodium silicate (NA4SiO4) is preferably used, and as the aluminum compound, for example, aluminum sulfate (Al2(SO4)3) is preferably used.

使用量はケイ素化合物の場合鉄に対してＳｉが重量比で
０．２％以下であると焼結防止効果がなく３０％以上で
あると飽和磁化が上がらないため０．２％〜３０％とす
るのが好ましく、０．５％〜２０％とするのがより好ま
しい。又、アルミニウム化合物の場合鉄に対してＡｌが
重量比で０．０１％以下であると焼結防止効果がなく５
％以上であると粒子の崩壊が訃こ）飽和磁化が低下する
ため０．０１％〜５％とするのが好ましく、０．１％〜
２％とするのがより好ましい。な卦、焼結防止処理に当
つてはニツケル含有α−オキシ水酸化鉄粉末を一旦加熱
脱水してニツケル含有α−ヘマタイト粉末とした後、ケ
イ素化合物またはアルミニウム化合物もしくは両者を含
む溶液中に浸漬処理して行なつてもよく、またニッケル
含有α−オキシ水酸化鉄粉末をまずアルミニウム化合物
を含む溶液中に浸漬処理し、次いで加熱脱水してニツケ
ル含有α−ヘマタイト粉末とした後、これをケイ素化合
物を含む溶液中に浸漬処理して行なつてもよい。In the case of silicon compounds, the amount to be used is 0.2% to 30% because if the weight ratio of Si to iron is less than 0.2%, there will be no sintering prevention effect, and if it is more than 30%, the saturation magnetization will not increase. The content is preferably 0.5% to 20%, and more preferably 0.5% to 20%. In addition, in the case of aluminum compounds, if the weight ratio of Al to iron is less than 0.01%, there is no sintering prevention effect5.
If it exceeds 0.01%, the saturation magnetization will decrease, and preferably 0.1% to 5%.
More preferably, it is 2%. For the sintering prevention treatment, nickel-containing α-iron oxyhydroxide powder is heated and dehydrated to form nickel-containing α-hematite powder, and then immersed in a solution containing a silicon compound, an aluminum compound, or both. Alternatively, the nickel-containing α-iron oxyhydroxide powder may be first immersed in a solution containing an aluminum compound, then heated and dehydrated to form a nickel-containing α-hematite powder, which is then converted into a silicon compound. The treatment may also be carried out by immersion treatment in a solution containing.

このような焼結防止処理により、加熱還元時の粉末粒子
間の焼結は有効に防止され、従つてこれらの焼結防止処
理を施こしたニツケル含有α−オキシ水酸化鉄粉末また
はニツケル含有α−ヘマタイト粉末を還元ガス、たとえ
ば水素気流中で３００〜５００℃で加熱還元すると枝分
れがほとんどなく比較的粒子径が小さくて粒度分布の均
一な針状のニツケル含有磁性金属鉄粉末が得られ、磁気
特性が一段と向上する。Such sintering prevention treatment effectively prevents sintering between powder particles during thermal reduction, and therefore nickel-containing α-iron oxyhydroxide powder or nickel-containing α-iron oxyhydroxide powder that has undergone these sintering prevention treatments - When hematite powder is heated and reduced at 300 to 500°C in a reducing gas such as hydrogen stream, an acicular nickel-containing magnetic metal iron powder with almost no branching, relatively small particle size, and uniform particle size distribution can be obtained. , the magnetic properties are further improved.

次に、この発明の実施例について説明する。Next, embodiments of the invention will be described.

実施例 １濃度５モル／ｌの水酸化ナトリウム水溶液１
．５１フ“０ に、室温で攪拌しながら硫酸第一鉄（ＦｅＳＯ４）と硫
酸第一ニツケル（ＮｉＳＯ４）の混合溶液ＦｅｓＯ４の
濃度０．７１９モル／１．ＮｉＳＯ４の濃度０．０３モ
ル／１１鉄に対するニツケルの原子比５．０％）１．５
１を加えて反応させ、水酸化第一鉄と水酸化第一ニツケ
ルの緑色を帯びた乳白色共同沈殿物を得た。Example 1 Aqueous sodium hydroxide solution 1 with a concentration of 5 mol/l
．． A mixed solution of ferrous sulfate (FeSO4) and nickel sulfate (NiSO4) was prepared at room temperature with stirring at a concentration of 0.719 mol/1.Concentration of NiSO4 was 0.719 mol/1. Nickel atomic ratio 5.0%) 1.5
1 was added and reacted to obtain a greenish, opalescent co-precipitate of ferrous hydroxide and nickel hydroxide.

この懸濁液のＰＨは１２以上であつた。次いでこの共同
沈殿物懸濁液を４０℃に保ちながら１．６１／分の速度
で空気を吹き込み８時間攪拌した。The pH of this suspension was 12 or higher. Then, air was blown into the co-precipitate suspension at a rate of 1.61/min and stirred for 8 hours while maintaining the co-precipitate suspension at 40°C.

この攪拌で生成した黄色の沈殿物をろ別し、充分に水洗
した後１００℃で乾燥したところ、粒径０．４μ、軸比
１５のニツケル含有α−オキシ水酸化鉄粉末を得た。次
に、この粉末１００ｇを濃度０．０１８モノＺｑのケイ
酸ナトリウム（Ｎａ４ＳｉＯ４）水溶液６１中に分散さ
せ、５１／分の速度で炭酸ガスを吹き込んで処理した後
水洗、乾燥した。The yellow precipitate produced by this stirring was filtered out, thoroughly washed with water, and then dried at 100°C to obtain a nickel-containing α-iron oxyhydroxide powder with a particle size of 0.4 μm and an axial ratio of 15. Next, 100 g of this powder was dispersed in a sodium silicate (Na4SiO4) aqueous solution 61 having a concentration of 0.018 monoZq, treated by blowing carbon dioxide gas at a rate of 51/min, washed with water, and dried.

処理後の粉末１ｇを石英ボード中に均一に展開し、管状
電気炉内に載置して水素ガスを１１／分の速度で通気し
、４００℃で加熱還元した。1 g of the treated powder was spread uniformly on a quartz board, placed in a tubular electric furnace, hydrogen gas was passed through the board at a rate of 11/min, and the board was heated and reduced at 400°C.

還元終了空気中での発火を防ぐため一旦トルエンに浸し
てから取り出し、ニツケル含有磁性金属粉末を得た。実
施例 ２ 実施例１と同様にしてニツケル含有α−オキシ水酸化鉄
粉末を製造し、粒径０．４μ、軸比１５のニツケル含有
α−オキシ水酸化鉄粉末を得た後、この粉末１００ｇを
ケイ酸ナトリウム（Ｎａ４ＳｉＯ４）と硫酸アルミニウ
ム（Ａｌ２（ＳＯ４）３）の混合水溶液（Ｎａ４ＳｌＯ
４の濃度０．０１８モル／ｌ、Ａ１２（ＳＯ４）３の濃
度１．９５×１０モル／ｌ）６１中に分散させ、５１／
分の速度で炭酸ガスを吹き込んで処理した後水洗、乾燥
した。After completion of reduction, to prevent ignition in the air, it was immersed in toluene and then taken out to obtain a nickel-containing magnetic metal powder. Example 2 A nickel-containing α-iron oxyhydroxide powder was produced in the same manner as in Example 1 to obtain a nickel-containing α-iron oxyhydroxide powder with a particle size of 0.4 μ and an axial ratio of 15, and then 100 g of this powder was obtained. A mixed aqueous solution of sodium silicate (Na4SiO4) and aluminum sulfate (Al2(SO4)3) (Na4SlO
4 (concentration 0.018 mol/l, A12(SO4)3 concentration 1.95×10 mol/l) 61, 51/
It was treated by blowing carbon dioxide gas at a rate of 1 minute, then washed with water and dried.

次いで処理後の粉末１ｇを採取し実施例１と同様にして
加熱還元し、ニツケル含有磁性金属鉄粉末を得た。Next, 1 g of the treated powder was collected and heated and reduced in the same manner as in Example 1 to obtain a nickel-containing magnetic metal iron powder.

実施例 ３ 実施例１と同様にしてニツケル含有α−オキシ水酸化鉄
粉末を製造し、粒径０．４μ、軸比１５のニツケル含有
α−オキシ水酸化鉄粉末を得た。Example 3 A nickel-containing α-iron oxyhydroxide powder was produced in the same manner as in Example 1 to obtain a nickel-containing α-iron oxyhydroxide powder having a particle size of 0.4 μm and an axial ratio of 15.

次いでこの粉末を空気中で３００℃の条件下に３時間加
熱脱水してニツケル含有α−ヘマタイト粉末とした。こ
の粉末１００ｇを濃度０．０１８モル／ｌのケイ酸ナト
リウム（Ｎａ４ＳｉＯ４）水溶液６１中に分散させ、５
１／分の速度で炭酸ガスを吹き込んで処理した後水洗、
乾燥した。次いで処理後の粉末１ｇを採取した実施例１
と同様にして加熱還元し、−ツケル含有磁性金属鉄粉末
を得た。Next, this powder was heated and dehydrated in air at 300° C. for 3 hours to obtain a nickel-containing α-hematite powder. 100 g of this powder was dispersed in a sodium silicate (Na4SiO4) aqueous solution 61 with a concentration of 0.018 mol/l,
After treatment by blowing carbon dioxide gas at a rate of 1/min, washing with water,
Dry. Example 1: 1 g of powder was then collected after treatment.
The mixture was heated and reduced in the same manner as in the above to obtain a magnetic metallic iron powder containing -Tsukeru.

実施例 ４ 実施例３と同様にしてニツケル含有α−ヘマタイト粉末
を得た後、この粉末１００ｇをケイ酸ナトリウム（Ｎａ
４ＳｉＯ４）ど硫酸アルミニウム（Ａｌ２（ＳＯ４）３
）の混合水溶液（Ｎａ４ＳｉＯ４の濃度０．０１８モル
／１．Ａｌ２（ＳＯ４）３の濃度１．９５Ｘ１０モル／
ｌ）６′中に分散させ、５１／分の速度で炭酸ガスを吹
き込んで処理した後、水洗、乾燥した。Example 4 After obtaining nickel-containing α-hematite powder in the same manner as in Example 3, 100 g of this powder was mixed with sodium silicate (Na
4SiO4) Aluminum sulfate (Al2(SO4)3
) mixed aqueous solution (Na4SiO4 concentration 0.018 mol/1.Al2(SO4)3 concentration 1.95X10 mol/
l) 6' and treated by blowing carbon dioxide gas at a rate of 51/min, followed by washing with water and drying.

次いで処理後の粉末１ｇを採取して実施例１と同様にし
て加熱還元し、ニツケル含有磁性金属鉄粉末を得た。比
較例 濃度５モル／ｌの水酸化ナトリウム水溶液１．５１に、
室温で攪拌しながら濃度０．７１９モル／ｌの硫酸第一
鉄（ＦｅＳＯ４）水溶液１．５１を加えて反応させ、水
酸化第一鉄の白緑色の沈殿を得た。Next, 1 g of the treated powder was collected and heated and reduced in the same manner as in Example 1 to obtain a nickel-containing magnetic metallic iron powder. Comparative Example Into 1.51 of a sodium hydroxide aqueous solution with a concentration of 5 mol/l,
While stirring at room temperature, 1.51 ml of an aqueous solution of ferrous sulfate (FeSO4) having a concentration of 0.719 mol/l was added and reacted to obtain a white-green precipitate of ferrous hydroxide.

この懸濁液のＰＨは１２以上であつた。次いでこの水酸
化第一鉄の懸濁液を４０℃に保ちながら１、６１／分の
速度で空気を吹き込み８時 二間攪拌した。The pH of this suspension was 12 or higher. Next, air was blown into the ferrous hydroxide suspension at a rate of 1.61/min while maintaining the temperature at 40° C., and the suspension was stirred for 8 hours and 2 hours.

この攪拌で生成した黄色の沈殿物をろ別し、充分に水洗
した後１００℃で乾燥したところ、粒径０．５μ、軸比
１５のα−オキシ水酸化鉄粉末を得た。次に、この粉末
１００ｇをケイ酸ナトリウム（Ｎａ４ＳｌＯ４）と硫酸
アルミニウム（Ａｌ２（ＳＯ４）３）の混合水溶液（Ｎ
ａ４ＳｉＯ４の濃度０．０１８七吟ｑ１Ａ２２（ＳＯ４
）３の濃度１．９５Ｘ１０モノレ／ｌ）６１中に分散さ
せ、５１／分の速度で炭酸ガスを吹き込んで処理した後
水洗、乾燥した。The yellow precipitate produced by this stirring was filtered out, thoroughly washed with water, and then dried at 100°C to obtain α-iron oxyhydroxide powder with a particle size of 0.5 μm and an axial ratio of 15. Next, 100 g of this powder was added to a mixed aqueous solution (N
a4SiO4 concentration 0.018 Shichiginq1A22 (SO4
) 3 at a concentration of 1.95×10 monomer/l) 61, treated by blowing carbon dioxide gas at a rate of 51/min, washed with water, and dried.

次いで、処理後の粉末１ｇを採取して実施例１と同様に
して加熱還元し、磁性金属鉄粉末を得た。Next, 1 g of the treated powder was collected and heated and reduced in the same manner as in Example 1 to obtain magnetic metal iron powder.

各実施例で得られたニツケル含有磁性金属鉄粉末および
比較例で得られた磁性金属鉄粉末の飽和磁化（σ８）、
保磁力（Ｈｃ）および角型比（σｒ／σ８）を測定した
結果は下表に示すとおりであつた。国ミ 上記から明らかなように、この発明方法によつて得られ
たニツケル含有磁性金属鉄粉末（実施例１〜４）はいず
れも従来の磁性金属鉄粉末（比較例）に比し、保磁力お
よび角型比が高く、このことからこの発明方法によつて
得られる磁性金属粉末は磁気特性が一段と優れているこ
とがわかる。Saturation magnetization (σ8) of the nickel-containing magnetic metal iron powder obtained in each example and the magnetic metal iron powder obtained in the comparative example,
The results of measuring coercive force (Hc) and squareness ratio (σr/σ8) were as shown in the table below. As is clear from the above, the nickel-containing magnetic metal iron powders (Examples 1 to 4) obtained by the method of this invention all have a higher coercive force than the conventional magnetic metal iron powder (comparative example). and a high squareness ratio, which indicates that the magnetic metal powder obtained by the method of the present invention has even better magnetic properties.

Claims (1)

【特許請求の範囲】[Claims] １ 第一鉄塩と第一ニッケル塩の混合溶液とアルカリ溶
液とを混合して水酸化第一鉄と水酸化第一ニッケルを共
沈させた後、あるいは第一鉄塩溶液と第一ニッケル塩溶
液の各々にアルカリ溶液を加えて水酸化第一鉄と水酸化
第一ニッケルを別々に沈殿させてから混合した後、この
沈殿物懸濁液に酸素含有ガスを接触させてニッケル含有
α−オキシ水酸化鉄粉末を生成し、ろ過、乾燥後この生
成粉末をケイ素化合物およびアルミニウム化合物から選
ばれる一種又は二種の化合物を含む溶液中に浸漬処理し
た後、還元ガスで加熱還元してニッケル含有磁性金属鉄
粉末とすることを特徴とする磁性金属粉末の製造方法。1 After co-precipitating ferrous hydroxide and nickel hydroxide by mixing a mixed solution of ferrous salt and nickel salt and an alkaline solution, or after co-precipitating ferrous hydroxide and nickel hydroxide, or after co-precipitating ferrous salt solution and nickel salt An alkaline solution is added to each of the solutions to precipitate ferrous hydroxide and nickel hydroxide separately, and then mixed, the precipitate suspension is contacted with an oxygen-containing gas to form nickel-containing α-oxy After producing iron hydroxide powder, filtering and drying, the produced powder is immersed in a solution containing one or two compounds selected from silicon compounds and aluminum compounds, and then heated and reduced with a reducing gas to produce nickel-containing magnetism. A method for producing magnetic metal powder, characterized in that it is a metal iron powder.