【０００１】
【産業上の利用分野】
この発明は、鉄、Ｆｅ−Ｓｉ系鉄基軟磁性合金、Ｆｅ−Ａｌ系鉄基軟磁性合金、Ｆｅ−Ｓｉ−Ａｌ系鉄基軟磁性合金、Ｆｅ−Ｃｒ系鉄基軟磁性合金またはニッケル基軟磁性合金（以下、これらを軟磁性合金という）粒の粒界に水素化物を形成することができまた窒化物をも形成することのできる金属（以下、水素化物・窒化物形成可能金属という）の窒化物が介在する組織を有する金属窒化物介在軟磁性焼結合金の製造方法に関するものである。
【０００２】
【従来の技術】
前記軟磁性合金の粉末を燒結して得られた軟磁性焼結合金は高磁束密度を有しているが、固有抵抗が低く、これを磁心として用いると、渦電流損失が発生して実効透磁率が低下するために、高周波用としては使用できない。これを避けるために、軟磁性合金の粉末の表面に固有抵抗の大きい金属窒化物を被覆した金属窒化物層被覆軟磁性粉末を作製し、この金属窒化物層被覆軟磁性粉末を燒結して軟磁性合金粒の粒界に固有抵抗の大きい金属窒化物を介在させた組織を有する金属窒化物介在軟磁性焼結合金がすでに提案されている。この金属窒化物介在軟磁性焼結合金は軟磁性合金粒の粒界に固有抵抗の大きな金属窒化物が介在しているために、抵抗値が大きくなり、渦電流損失の発生は大幅に低下するところから高周波用として使用できるとされている。
【０００３】
この軟磁性合金粒の粒界に固有抵抗の大きい物質が介在している組織を有する金属窒化物介在軟磁性焼結合金は、軟磁性合金粉末に、金属窒化物のコロイドを混合して金属窒化物層被覆軟磁性粉末を作製し、この金属窒化物層被覆軟磁性粉末を焼結することにより作られる（例えば、特許文献１参照）。
【０００４】
【特許文献１】
特開平５−２５８９３号公報
【０００５】
【発明が解決しようとする課題】
しかし、軟磁性合金粉末の表面に金属窒化物層を被覆してなる従来の金属窒化物層被覆軟磁性粉末は、金属窒化物が高融点を有するために軟磁性粉末の通常の焼結温度では拡散し固溶することが少ないところから、金属窒化物層は軟磁性合金粉末同士の焼結接合を妨げ、十分な機械的強度および密度を有する金属窒化物介在軟磁性焼結合金は得られないという欠点がある。
ところが、近年、これら金属窒化物介在軟磁性焼結合金は、電話機振動板、ドットプリンターのヘッド、電磁弁、プランジャーなどの振動または衝撃を受ける部品にも使用されようとしており、前記従来の金属窒化物介在軟磁性焼結合金では機械的強度が不十分であって、かかる振動または衝撃を受ける部品に使用することができない。したがって、従来の金属窒化物介在軟磁性焼結合金よりも一層高強度および高密度で磁気特性に優れた金属窒化物介在軟磁性焼結合金が求められている。
【０００６】
【課題を解決するための手段】
そこで、本発明者らは、高強度、高密度を有しかつ高抵抗を有する金属窒化物介在軟磁性焼結合金を得るべく研究を行った。その結果、
（イ）軟磁性合金粉末に、水素化物を形成することができまた窒化物をも形成することのできる金属（以下、水素化物・窒化物形成可能金属という）の水素化物粉末を添加し、粉砕混合して混合粉末を作製し、得られた混合粉末を圧密成形して圧密成形体を作製し、得られた圧密成形体を非酸化雰囲気中、温度：１０００〜１３００℃、１〜３時間保持の条件でで燒結して軟磁性合金粒の粒界に金属水素化物が介在する組織を有する焼結体を作製し、得られた焼結体を温度：３００〜８００℃、３〜１０時間保持の条件で窒化処理すると、軟磁性合金粒の粒界に金属水素化物が介在する組織を有する焼結体の金属水素化物は金属窒化物に置換されて金属窒化物が介在する組織を有する金属窒化物介在軟磁性焼結合金が得られ、この金属水素化物から置換して得られた金属窒化物が介在する金属窒化物介在軟磁性焼結合金は、従来の軟磁性合金粉末の表面に金属窒化物層を被覆してなる金属窒化物層被覆軟磁性粉末を燒結して得られた金属窒化物介在軟磁性焼結合金に比べて強度および密度が格段に向上し、その値は抗折強度＞８０ＭＰａ、相対密度＞９５％となる、
（ロ）前記圧密成形体を燒結して粒界に金属水素化物が介在する組織を有する焼結体を作製する非酸化雰囲気は、真空雰囲気、不活性ガス雰囲気または窒素ガス雰囲気の何れでも良く、また焼結体を窒化処理する雰囲気は窒素ガス雰囲気が好ましい、
（ハ）前記水素化物・窒化物形成可能金属は、Ｙを含む希土類元素（以下、Ｒで示す）、Ａｌ、Ｌｉ、Ｃａ、Ｓｒ、Ｍｇの内のいずれかであることが好ましい、などの研究結果が得られたのである。
【０００７】
この発明は、かかる研究結果に基づいてなされたものであって、
（１）軟磁性合金粉末に、水素化物・窒化物形成可能金属の水素化物粉末を添加し、粉砕混合して混合粉末を作製し、得られた混合粉末を圧密成形して圧密成形体を作製し、得られた圧密成形体を非酸化雰囲気中で燒結して焼結体を作製し、この焼結体を窒化処理する軟磁性合金粒の粒界に金属窒化物が介在する組織を有する金属窒化物介在軟磁性焼結合金の製造方法、
（２）軟磁性合金粉末に、水素化物・窒化物形成可能金属の水素化物粉末を添加し、粉砕混合して混合粉末を作製し、得られた混合粉末を圧密成形して圧密成形体を作製し、得られた圧密成形体を非酸化雰囲気中、温度：１０００〜１３００℃で燒結して焼結体を作製し、得られた焼結体を温度：３００〜８００℃で窒化処理する軟磁性合金粒の粒界に金属窒化物が介在する組織を有する金属窒化物介在軟磁性焼結合金の製造方法、
（３）軟磁性合金粉末に、水素化物・窒化物形成可能金属の水素化物粉末を添加し、粉砕混合して混合粉末を作製し、得られた混合粉末を圧密成形して圧密成形体を作製し、得られた圧密成形体を窒素ガス雰囲気中で燒結して焼結体を作製し、この焼結体を窒化処理する軟磁性合金粒の粒界に金属窒化物が介在する組織を有する金属窒化物介在軟磁性焼結合金の製造方法、
（４）軟磁性合金粉末に、水素化物・窒化物形成可能金属の水素化物粉末を添加し、粉砕混合して混合粉末を作製し、得られた混合粉末を圧密成形して圧密成形体を作製し、得られた圧密成形体を窒素ガス雰囲気中、温度：１０００〜１３００℃で燒結して焼結体を作製し、得られた焼結体を温度：３００〜８００℃で窒化処理する軟磁性合金粒の粒界に金属窒化物が介在する組織を有する金属窒化物介在軟磁性焼結合金の製造方法、
（５）軟磁性合金粉末に、水素化物・窒化物形成可能金属の水素化物粉末を添加し、粉砕混合して混合粉末を作製し、得られた混合粉末を圧密成形して圧密成形体を作製し、得られた圧密成形体を真空または不活性ガス雰囲気中で燒結して焼結体を作製し、この焼結体を窒化処理する軟磁性合金粒の粒界に金属窒化物が介在する組織を有する金属窒化物介在軟磁性焼結合金の製造方法、
（６）軟磁性合金粉末に、水素化物・窒化物形成可能金属の水素化物粉末を添加し、粉砕混合して混合粉末を作製し、得られた混合粉末を圧密成形して圧密成形体を作製し、得られた圧密成形体を真空または不活性ガス雰囲気中、温度：１０００〜１３００℃で燒結して焼結体を作製し、得られた焼結体を温度：３００〜８００℃で窒化処理する軟磁性合金粒の粒界に金属窒化物が介在する組織を有する金属窒化物介在軟磁性焼結合金の製造方法、に特徴を有するものである。
【０００８】
この発明の軟磁性合金粒の粒界に金属窒化物が介在する組織を有する金属窒化物介在軟磁性焼結合金を製造する方法において、原料粉末として使用する軟磁性合金粉末は平均粒径：１０〜１５０μｍを有することが好ましく、また原料粉末として使用する金属水素化物粉末は軟磁性合金粉末よりも微細な平均粒径：１〜１０μｍを有する金属水素化物粉末を用いることが好ましいが、その形状および寸法は特に限定されるものではない。その理由は、軟磁性合金粉末と金属水素化物粉末をボールミルなどの破砕混合機に装入し、混合すると、軟磁性合金粉末よりも微細な平均粒径：１〜１０μｍを有する金属水素化物粉末は破砕しやすいので一層微細化するが、軟磁性合金粉末は破砕しにくいので金属水素化物は粉末でなくても先に破砕されて粉末となり、一方、軟磁性合金粉末の平均粒径は殆ど変化することがないからである。
また、この発明の軟磁性合金粒の粒界に金属窒化物が介在する組織を有する金属窒化物介在軟磁性焼結合金を製造する際に、軟磁性合金粉末に対して配合する水素化物・窒化物形成可能金属（Ｒ、Ａｌ、Ｌｉ、Ｃａ、Ｓｒ、Ｍｇの内のいずれか）の水素化物粉末の量は、０．０５〜５質量％の範囲内に有ることが好ましい。０．０５質量％未満含有しても高抵抗化の効果が十分でなく、一方、５質量％を越えて含有すると、磁気特性の低下が大きいので好ましくないからである。
【０００９】
この発明の金属窒化物介在軟磁性合金を製造するための原料粉末である軟磁性合金粉末は、アトマイズ法、電解法、還元法のいずれかの方法で作製した軟磁性合金粉末を使用することができる。
そして、この発明の軟磁性焼結合金の製造方法において使用する軟磁性合金粉末は、具体的には、鉄粉末、Ｆｅ−Ｓｉ系鉄基軟磁性合金粉末、Ｆｅ−Ａｌ系鉄基軟磁性合金粉末、Ｆｅ−Ｓｉ−Ａｌ系鉄基軟磁性合金粉末、Ｆｅ−Ｃｒ系鉄基軟磁性合金粉末またはニッケル基軟磁性合金粉末の内のいすれかであって、これら軟磁性合金粉末は従来から一般に知られている軟磁性合金粉末であり、さらに具体的には、鉄粉末、
Ｓｉ：０．１〜１０％を含有し、残部がＦｅおよび不可避不純物からなるＦｅ−Ｓｉ系鉄基軟磁性合金粉末、
Ｓｉ：０．１〜１０％、Ａｌ：０．１〜２０％を含有し、残部がＦｅおよび不可避不純物からなるＦｅ−Ｓｉ−Ａｌ系鉄基軟磁性合金粉末、
Ａｌ：０．１〜２０％を含有し、残部がＦｅおよび不可避不純物からなるＦｅ−Ａｌ系鉄基軟磁性合金粉末、
Ｃｒ：１〜２０％を含有し、必要に応じてＡｌ：５％以下、Ｓｉ：５％以下の内の１種または２種を含有し、残部がＦｅおよび不可避不純物からなるＦｅ−Ｃｒ系鉄基軟磁性合金粉末、または、
Ｎｉ：３５〜８５％を含有し、必要に応じてＭｏ：５％以下、Ｃｕ：５％以下、Ｃｒ：２％以下、Ｍｎ：０．５％以下の１種または２種以上を含有し、残部がＦｅおよび不可避不純物からなるニッケル基軟磁性合金粉末などの金属軟磁性粉末を使用することができる。
【００１０】
前記圧密成形体を非酸化雰囲気中、温度：１０００〜１３００℃で燒結して得られた焼結体は、軟磁性合金粒の粒界に水素化物が脱水素して水素化物・窒化物形成可能金属が介在する組織が形成される。この時の非酸化雰囲気は真空又は不活性ガス雰囲気であり、このときの１０００〜１３００℃という温度は金属水素化物が脱水素する温度範囲として一般に知られている温度範囲である。
この脱水素した焼結体の粒界に介在する水素化物・窒化物形成可能金属は窒化物を形成しやすく、前記焼結体を引き続いて窒化処理すると、焼結体の粒界に存在する水素化物・窒化物形成可能金属は窒化して焼結体内部中心部まで金属窒化物相を形成する。この時の窒化処理条件は、窒素雰囲気中、温度：１０００〜１３００℃で１〜３時間加熱した後、同雰囲気のまま３００〜８００℃で３〜１０時間保持することにより行なわれる。
【００１１】
水素化物・窒化物形成可能金属は、Ｒ、Ａｌ、Ｌｉ、Ｃａ、Ｓｒ、Ｍｇの内のいずれかである。ただし、Ｒは、Ｙ，Ｃｅ，Ｌａ，Ｐｒ，Ｎｄ，Ｓｍ，Ｇｄ，Ｈｏ，Ｅｒ，Ｙｂ，Ｌｕの内のいずれかである。したがって、この発明の金属窒化物介在軟磁性合金を製造するための原料粉末である水素化物・窒化物形成可能金属の水素化物粉末は、具体的には、水素化Ｒ粉末、水素化Ａｌ粉末、水素化Ｌｉ粉末、水素化Ｃａ粉末、水素化Ｓｒ粉末、水素化Ｍｇ粉末の内のいずれかである。水素化Ｒ粉末のうちでも水素化Ｙ粉末，水素化Ｃｅ粉末，水素化Ｌａ粉末，水素化Ｎｄ粉末，水素化Ｓｍ粉末が最も入手しやすいので使用しやすい。
【００１２】
【発明の実施の形態】
原料粉末として、いずれも平均粒径：６０μｍを有し、いずれもガスアトマイズすることにより製造した、純鉄粉末、
Ｓｉ：３％を含有し、残部がＦｅおよび不可避不純物からなるＦｅ−Ｓｉ系鉄基軟磁性合金粉末、
Ｓｉ：３％、Ａｌ：３％を含有し、残部がＦｅおよび不可避不純物からなるＦｅ−Ｓｉ−Ａｌ系鉄基軟磁性合金粉末、
Ａｌ：５％を含有し、残部がＦｅおよび不可避不純物からなるＦｅ−Ａｌ系鉄基軟磁性合金粉末、
Ｃｒ：１７％を含有し、残部がＦｅおよび不可避不純物からなるＦｅ−Ｃｒ系鉄基軟磁性合金粉末、
Ｎｉ：２０％を含有し、残部がＦｅおよび不可避不純物からなるニッケル基軟磁性合金粉末を用意した。さらに、いずれも平均粒径：３μｍを有する水素化Ａｌ粉末、水素化Ｌｉ粉末、水素化Ｃａ粉末、水素化Ｓｒ粉末、水素化Ｍｇ粉末、水素化Ｙ粉末，水素化Ｃｅ粉末，水素化Ｌａ粉末，水素化Ｎｄ粉末，水素化Ｓｍ粉末を用意した。
【００１３】
実施例１
先に用意した純鉄粉末に水素化物粉末を表１に示される割合で配合し、ボールミルに装入し、回転数：８０ｒ．ｐ．ｍ．で５時間回転することにより粉砕混合して混合粉末を作製した。得られた混合粉末を６ｔｏｎ／ｃｍ２の成形圧をかけることにより縦：４０ｍｍ、横：１０ｍｍ、厚さ：５ｍｍの寸法を有する圧密体を成形し、得られた圧密体を表２に示される雰囲気および温度で焼結し、次に表２に示される条件で窒化処理して粒界に金属窒化物が介在する金属窒化物介在軟磁性焼結合金を製造することにより本発明法１〜１２および比較法１〜６を実施した。
比較のために、純鉄粉末の表面にコロイドＡｌＮを被覆した従来のＡｌＮ被覆軟磁性粉末を用意し、この従来粉末を６ｔｏｎ／ｃｍ２の成形圧をかけることにより縦：４０ｍｍ、横：１０ｍｍ、厚さ：５ｍｍの寸法を有する圧密体を成形し、得られた圧密体を窒素雰囲気中で燒結することにより粒界にＡｌＮが介在した金属窒化物介在軟磁性焼結合金を作製することにより従来法１を実施した。
【００１４】
本発明法１〜１０、比較法１〜６および従来法１により得られた金属窒化物介在軟磁性焼結合金について相対密度および抗折力を測定し、その結果を表２に示し、さらに、飽和磁束密度Ｂ１０Ｋ（ただし、Ｂ１０Ｋは外部磁界１０ｋＡを加えたときの磁束密度の値を示す。以下同じ）、比抵抗および周波数：１００ＫＨｚの高周波における比透磁率を測定し、その結果を表２に示した。
【００１５】
【表１】
【００１６】
【表２】
【００１７】
表１〜表２に示される結果から、本発明法１〜１０で作製した金属窒化物介在軟磁性焼結合金は、従来法１で作製した金属窒化物介在軟磁性焼結合金に比べて相対密度、強度、磁気特性が共に優れていることが分かる。しかし、比較法１〜６で作製した金属窒化物介在軟磁性焼結合金は前記特性の内の少なくとも１つが不満足な特性を示すことが分かる。
【００１８】
実施例２
先に用意したＦｅ−Ｓｉ系鉄基軟磁性合金粉末に水素化物粉末を表３に示される割合で配合し、ボールミルに装入し、回転数：８０ｒ．ｐ．ｍ．で５時間回転することにより粉砕混合して混合粉末を作製した。得られた混合粉末を６ｔｏｎ／ｃｍ２の成形圧をかけることにより縦：４０ｍｍ、横：１０ｍｍ、厚さ：５ｍｍの寸法を有する圧密体を成形し、得られた圧密体を表４に示される雰囲気および温度で焼結し、次に表４に示される条件で窒化処理して粒界に金属窒化物が介在する金属窒化物介在軟磁性焼結合金を製造することにより本発明法１１〜２０および比較法７〜１２を実施した。
比較のために、Ｆｅ−Ｓｉ系鉄基軟磁性合金粉末の表面にコロイドＡｌＮを被覆した従来のＡｌＮ被覆軟磁性粉末を用意し、この従来粉末を６ｔｏｎ／ｃｍ２の成形圧をかけることにより縦：４０ｍｍ、横：１０ｍｍ、厚さ：５ｍｍの寸法を有する圧密体を成形し、得られた圧密体を窒素雰囲気中で燒結することにより粒界にＡｌＮが介在した金属窒化物介在軟磁性焼結合金を作製することにより従来法２を実施した。
【００１９】
本発明法１１〜２０、比較法７〜１２および従来法２により得られた金属窒化物介在軟磁性焼結合金について相対密度および抗折力を測定し、その結果を表４に示し、さらに、飽和磁束密度Ｂ１０Ｋ、比抵抗および周波数：１００ＫＨｚの高周波における比透磁率を測定し、その結果を表４に示した。
【００２０】
【表３】
【００２１】
【表４】
【００２２】
表３〜表４に示される結果から、本発明法１１〜２０で作製した金属窒化物介在軟磁性焼結合金は、従来法２で作製した金属窒化物介在軟磁性焼結合金に比べて相対密度、強度、磁気特性が共に優れていることが分かる。しかし、比較法７〜１２で作製した金属窒化物介在軟磁性焼結合金は前記特性の内の少なくとも１つが不満足な特性を示すことが分かる。
【００２３】
実施例３
先に用意したＦｅ−Ｓｉ−Ａｌ系鉄基軟磁性合金粉末に水素化物粉末を表５に示される割合で配合し、ボールミルに装入し、回転数：８０ｒ．ｐ．ｍ．で４時間回転することにより粉砕混合して混合粉末を作製した。得られた混合粉末を６ｔｏｎ／ｃｍ２の成形圧をかけることにより縦：４０ｍｍ、横：１０ｍｍ、厚さ：５ｍｍの寸法を有する圧密体を成形し、得られた圧密体を表６に示される雰囲気および温度で焼結し、次に表６に示される条件で窒化処理して粒界に金属窒化物が介在する金属窒化物介在軟磁性焼結合金を製造することにより本発明法２１〜３０および比較法１３〜１８を実施した。
比較のために、Ｆｅ−Ｓｉ−Ａｌ系鉄基軟磁性合金粉末の表面にコロイドＡｌＮを被覆した従来のＡｌＮ被覆軟磁性粉末を用意し、この従来粉末を６ｔｏｎ／ｃｍ２の成形圧をかけることにより縦：４０ｍｍ、横：１０ｍｍ、厚さ：５ｍｍの寸法を有する圧密体を成形し、得られた圧密体を窒素雰囲気中で燒結することにより粒界にＡｌＮが介在した金属窒化物介在軟磁性焼結合金を作製することにより従来法３を実施した。
【００２４】
本発明法２１〜３０、比較法１３〜１８および従来法３により得られた金属窒化物介在軟磁性焼結合金について相対密度および抗折力を測定し、その結果を表６に示し、さらに、飽和磁束密度Ｂ１０Ｋ、比抵抗および周波数：１００ＫＨｚの高周波における比透磁率を測定し、その結果を表６に示した。
【００２５】
【表５】
【００２６】
【表６】
【００２７】
表５〜表６に示される結果から、本発明法２１〜３０で作製した金属窒化物介在軟磁性焼結合金は、従来法３で作製した金属窒化物介在軟磁性焼結合金に比べて相対密度、強度、磁気特性が共に優れていることが分かる。しかし、比較法１３〜１８で作製した金属窒化物介在軟磁性焼結合金は前記特性の内の少なくとも１つが不満足な特性を示すことが分かる。
【００２８】
実施例４
先に用意したＦｅ−Ａｌ系鉄基軟磁性合金粉末に水素化物粉末を表７に示される割合で配合し、ボールミルに装入し、回転数：８０ｒ．ｐ．ｍ．で４．５時間回転することにより粉砕混合して混合粉末を作製した。得られた混合粉末を６ｔｏｎ／ｃｍ２の成形圧をかけることにより縦：４０ｍｍ、横：１０ｍｍ、厚さ：５ｍｍの寸法を有する圧密体を成形し、得られた圧密体を表８に示される雰囲気および温度で焼結し、次に表８に示される条件で窒化処理して粒界に金属窒化物が介在する金属窒化物介在軟磁性焼結合金を製造することにより本発明法３１〜４０および比較法１９〜２４を実施した。
比較のために、Ｆｅ−Ａｌ系鉄基軟磁性合金粉末の表面にコロイドＡｌＮを被覆した従来のＡｌＮ被覆軟磁性粉末を用意し、この従来粉末を６ｔｏｎ／ｃｍ２の成形圧をかけることにより縦：４０ｍｍ、横：１０ｍｍ、厚さ：５ｍｍの寸法を有する圧密体を成形し、得られた圧密体を窒素雰囲気中で燒結することにより粒界にＡｌＮが介在した金属窒化物介在軟磁性焼結合金を作製することにより従来法４を実施した。
【００２９】
本発明法３１〜４０、比較法１９〜２４および従来法４により得られた金属窒化物介在軟磁性焼結合金について相対密度および抗折力を測定し、その結果を表８に示し、さらに、飽和磁束密度Ｂ１０Ｋ、比抵抗および周波数：１００ＫＨｚの高周波における比透磁率を測定し、その結果を表８に示した。
【００３０】
【表７】
【００３１】
【表８】
【００３２】
表７〜表８に示される結果から、本発明法３１〜４０で作製した金属窒化物介在軟磁性焼結合金は、従来法４で作製した金属窒化物介在軟磁性焼結合金に比べて相対密度、強度、磁気特性が共に優れていることが分かる。しかし、比較法１９〜２４で作製した金属窒化物介在軟磁性焼結合金は前記特性の内の少なくとも１つが不満足な特性を示すことが分かる。
【００３３】
実施例５
先に用意したＦｅ−Ｃｒ系鉄基軟磁性合金粉末に水素化物粉末を表９に示される割合で配合し、ボールミルに装入し、回転数：８０ｒ．ｐ．ｍ．で６時間回転することにより粉砕混合して混合粉末を作製した。得られた混合粉末を６ｔｏｎ／ｃｍ２の成形圧をかけることにより縦：４０ｍｍ、横：１０ｍｍ、厚さ：５ｍｍの寸法を有する圧密体を成形し、得られた圧密体を表１０に示される雰囲気および温度で焼結し、次に表１０に示される条件で窒化処理して粒界に金属窒化物が介在する金属窒化物介在軟磁性焼結合金を製造することにより本発明法４１〜５０および比較法２５〜３０を実施した。
比較のために、Ｆｅ−Ｃｒ系鉄基軟磁性合金粉末の表面にコロイドＡｌＮを被覆した従来のＡｌＮ被覆軟磁性粉末を用意し、この従来粉末を６ｔｏｎ／ｃｍ２の成形圧をかけることにより縦：４０ｍｍ、横：１０ｍｍ、厚さ：５ｍｍの寸法を有する圧密体を成形し、得られた圧密体を窒素雰囲気中で燒結することにより粒界にＡｌＮが介在した金属窒化物介在軟磁性焼結合金を作製することにより従来法５を実施した。
【００３４】
本発明法４１〜５０、比較法２５〜３０および従来法５により得られた金属窒化物介在軟磁性焼結合金について相対密度および抗折力を測定し、その結果を表１０に示し、さらに、飽和磁束密度Ｂ１０Ｋ、比抵抗および周波数：１００ＫＨｚの高周波における比透磁率を測定し、その結果を表１０に示した。
【００３５】
【表９】
【００３６】
【表１０】
【００３７】
表９〜表１０に示される結果から、本発明法４１〜５０で作製した金属窒化物介在軟磁性焼結合金は、従来法５で作製した金属窒化物介在軟磁性焼結合金に比べて相対密度、強度、磁気特性が共に優れていることが分かる。しかし、比較法２５〜３０で作製した金属窒化物介在軟磁性焼結合金は前記特性の内の少なくとも１つが不満足な特性を示すことが分かる。
【００３８】
実施例６
先に用意したニッケル基軟磁性合金粉末に水素化物粉末を表１１に示される割合で配合し、ボールミルに装入し、回転数：８０ｒ．ｐ．ｍ．で５．５時間回転することにより粉砕混合して混合粉末を作製した。得られた混合粉末を６ｔｏｎ／ｃｍ２の成形圧をかけることにより縦：４０ｍｍ、横：１０ｍｍ、厚さ：５ｍｍの寸法を有する圧密体を成形し、得られた圧密体を表１２に示される雰囲気および温度で焼結し、次に表１２に示される条件で窒化処理して粒界に金属窒化物が介在する金属窒化物介在軟磁性焼結合金を製造することにより本発明法５１〜６０および比較法３１〜３６を実施した。
比較のために、ニッケル基軟磁性合金粉末の表面にコロイドＡｌＮを被覆した従来のＡｌＮ被覆軟磁性粉末を用意し、この従来粉末を６ｔｏｎ／ｃｍ２の成形圧をかけることにより縦：４０ｍｍ、横：１０ｍｍ、厚さ：５ｍｍの寸法を有する圧密体を成形し、得られた圧密体を窒素雰囲気中で燒結することにより粒界にＡｌＮが介在した金属窒化物介在軟磁性焼結合金を作製することにより従来法６を実施した。
【００３９】
本発明法５１〜６０、比較法３１〜３６および従来法６により得られた金属窒化物介在軟磁性焼結合金について相対密度および抗折力を測定し、その結果を表１２に示し、さらに、飽和磁束密度Ｂ１０Ｋ、比抵抗および周波数：１００ＫＨｚの高周波における比透磁率を測定し、その結果を表１２に示した。
【００４０】
【表１１】
【００４１】
【表１２】
【００４２】
表１１〜表１２に示される結果から、本発明法５１〜６０で作製した金属窒化物介在軟磁性焼結合金は、従来法６で作製した金属窒化物介在軟磁性焼結合金に比べて相対密度、強度、磁気特性が共に優れていることが分かる。しかし、比較法３１〜３６で作製した金属窒化物介在軟磁性焼結合金は前記特性の内の少なくとも１つが不満足な特性を示すことが分かる。
【００４３】
【発明の効果】
この発明は、高密度で機械的強度が優れ、かつ高周波の比透磁率の高い金属窒化物介在軟磁性焼結合金を提供することができ、電気および電子産業において優れた効果をもたらすものである。[0001]
[Industrial application fields]
This invention relates to iron, Fe—Si based iron-based soft magnetic alloy, Fe—Al based iron based soft magnetic alloy, Fe—Si—Al based iron based soft magnetic alloy, Fe—Cr based iron based soft magnetic alloy or nickel based Metals capable of forming hydrides at the grain boundaries of soft magnetic alloys (hereinafter referred to as soft magnetic alloys) and also capable of forming nitrides (hereinafter referred to as hydride / nitride-forming metals) The present invention relates to a method for producing a metal nitride-containing soft magnetic sintered alloy having a structure in which a nitride is interposed.
[0002]
[Prior art]
The soft magnetic sintered alloy obtained by sintering the powder of the soft magnetic alloy has a high magnetic flux density, but has a low specific resistance. If this is used as a magnetic core, eddy current loss occurs and effective transmission is lost. Since the magnetic susceptibility is lowered, it cannot be used for high frequencies. In order to avoid this, a metal nitride layer-coated soft magnetic powder in which the surface of the soft magnetic alloy powder is coated with a metal nitride having a large specific resistance is produced, and this metal nitride layer-coated soft magnetic powder is sintered and softened. A metal nitride-mediated soft magnetic sintered alloy having a structure in which a metal nitride having a large specific resistance is interposed at the grain boundary of magnetic alloy grains has already been proposed. In this metal nitride intervening soft magnetic sintered alloy, the resistance value increases and the occurrence of eddy current loss is greatly reduced because the metal nitride having a large specific resistance is present at the grain boundary of the soft magnetic alloy grains. It is said that it can be used for high frequency.
[0003]
The metal nitride intervening soft magnetic sintered alloy having a structure in which a substance having a large specific resistance is present at the grain boundary of the soft magnetic alloy grain is obtained by mixing a metal nitride colloid into a soft magnetic alloy powder and performing metal nitriding. It is made by producing a physical layer-coated soft magnetic powder and sintering this metal nitride layer-coated soft magnetic powder (see, for example, Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 5-25893
[Problems to be solved by the invention]
However, the conventional metal nitride layer-coated soft magnetic powder obtained by coating the surface of the soft magnetic alloy powder with the metal nitride layer has a high melting point, so that the normal sintering temperature of the soft magnetic powder is low. The metal nitride layer prevents the soft magnetic alloy powders from being sintered and bonded together because the metal nitride layer hardly diffuses and dissolves, and a metal nitride intervening soft magnetic sintered alloy having sufficient mechanical strength and density cannot be obtained. There is a drawback.
However, in recent years, these metal nitride intervening soft magnetic sintered alloys have been used for parts subjected to vibration or impact such as telephone diaphragms, dot printer heads, solenoid valves, plungers, etc. A nitride-containing soft magnetic sintered alloy has insufficient mechanical strength and cannot be used for a component that receives such vibration or impact. Accordingly, there is a need for a metal nitride-mediated soft magnetic sintered alloy that has higher strength, higher density, and superior magnetic properties than conventional metal nitride-mediated soft magnetic sintered alloys.
[0006]
[Means for Solving the Problems]
Therefore, the present inventors have studied to obtain a metal nitride-mediated soft magnetic sintered alloy having high strength, high density and high resistance. as a result,
(B) A hydride powder of a metal capable of forming a hydride and capable of forming a nitride (hereinafter referred to as a hydride / nitride-forming metal) is added to the soft magnetic alloy powder and pulverized. A mixed powder is prepared by mixing, and the obtained mixed powder is compacted to prepare a compacted body. The compacted body is held in a non-oxidizing atmosphere at a temperature of 1000 to 1300 ° C. for 1 to 3 hours. A sintered body having a structure in which a metal hydride intervenes at the grain boundary of soft magnetic alloy grains is produced by sintering under the above conditions, and the obtained sintered body is maintained at a temperature of 300 to 800 ° C. for 3 to 10 hours. When the nitriding treatment is performed under the above conditions, the metal hydride of the sintered body having a structure in which the metal hydride is interposed at the grain boundary of the soft magnetic alloy grains is replaced with the metal nitride, and the metal nitriding having the structure in which the metal nitride is interposed An intervening soft magnetic sintered alloy is obtained, and this metal hydrogenation The metal nitride intercalated soft magnetic sintered alloy with the metal nitride intervening obtained by substituting from the above is a metal nitride layer-coated soft magnetic powder obtained by coating the surface of a conventional soft magnetic alloy powder with a metal nitride layer Compared with the metal nitride-mediated soft magnetic sintered alloy obtained by sintering, the strength and density are remarkably improved, and the values are bending strength> 80 MPa, relative density> 95%,
(B) The non-oxidizing atmosphere in which the compacted body is sintered to produce a sintered body having a structure in which metal hydrides are present at grain boundaries may be any of a vacuum atmosphere, an inert gas atmosphere, or a nitrogen gas atmosphere, The atmosphere for nitriding the sintered body is preferably a nitrogen gas atmosphere.
(C) Research such that the metal capable of forming hydrides and nitrides is preferably any of rare earth elements including Y (hereinafter referred to as R), Al, Li, Ca, Sr, and Mg. The result was obtained.
[0007]
The present invention has been made based on the results of such research,
(1) Add hydride / nitride-formable metal hydride powder to soft magnetic alloy powder, pulverize and mix to produce mixed powder, and then compact the resulting mixed powder to produce a compacted body. The resulting compacted body is sintered in a non-oxidizing atmosphere to produce a sintered body, and a metal having a structure in which a metal nitride is present at the grain boundary of soft magnetic alloy grains for nitriding the sintered body Method for producing nitride-mediated soft magnetic sintered alloy,
(2) Add hydride / nitride-formable metal hydride powder to soft magnetic alloy powder, pulverize and mix to produce mixed powder, and then compact the resulting mixed powder to produce a compacted body. Then, the obtained compacted body is sintered at a temperature of 1000 to 1300 ° C. in a non-oxidizing atmosphere to produce a sintered body, and the obtained sintered body is nitrided at a temperature of 300 to 800 ° C. A method for producing a metal nitride-mediated soft magnetic sintered alloy having a structure in which metal nitride is present at the grain boundaries of the alloy grains,
(3) Add hydride / nitride-formable metal hydride powder to soft magnetic alloy powder, pulverize and mix to produce mixed powder, and then compact the resulting mixed powder to produce a compacted body. Then, the obtained compacted body is sintered in a nitrogen gas atmosphere to produce a sintered body, and a metal having a structure in which a metal nitride is interposed at the grain boundary of soft magnetic alloy grains for nitriding the sintered body Method for producing nitride-mediated soft magnetic sintered alloy,
(4) Add hydride / nitride-formable metal hydride powder to soft magnetic alloy powder, pulverize and mix to produce mixed powder, and then compact the resulting mixed powder to produce a compacted body. Then, the obtained compacted body is sintered at a temperature of 1000 to 1300 ° C. in a nitrogen gas atmosphere to produce a sintered body, and the obtained sintered body is subjected to nitriding treatment at a temperature of 300 to 800 ° C. A method for producing a metal nitride-mediated soft magnetic sintered alloy having a structure in which metal nitride is present at the grain boundaries of the alloy grains,
(5) Add hydride / nitride-formable metal hydride powder to soft magnetic alloy powder, pulverize and mix to produce mixed powder, and then compact the resulting mixed powder to produce a compacted body. The resulting compacted body is sintered in a vacuum or an inert gas atmosphere to produce a sintered body, and a structure in which metal nitride is present at the grain boundaries of soft magnetic alloy grains for nitriding the sintered body A method for producing a metal nitride-mediated soft magnetic sintered alloy having
(6) Add hydride / nitride-formable metal hydride powder to soft magnetic alloy powder, pulverize and mix to produce mixed powder, and then compact the resulting mixed powder to produce a compacted body. Then, the obtained compacted body is sintered at a temperature of 1000 to 1300 ° C. in a vacuum or an inert gas atmosphere to produce a sintered body, and the obtained sintered body is subjected to nitriding treatment at a temperature of 300 to 800 ° C. The present invention is characterized by a method for producing a metal nitride-mediated soft magnetic sintered alloy having a structure in which metal nitride is present at grain boundaries of soft magnetic alloy grains.
[0008]
In the method for producing a metal nitride-mediated soft magnetic sintered alloy having a structure in which metal nitride is present at the grain boundaries of the soft magnetic alloy grains of the present invention, the soft magnetic alloy powder used as the raw material powder has an average particle size of 10 The metal hydride powder used as the raw material powder is preferably a metal hydride powder having an average particle diameter of 1 to 10 μm finer than that of the soft magnetic alloy powder. The dimensions are not particularly limited. The reason is that when the soft magnetic alloy powder and the metal hydride powder are charged into a crushing and mixing machine such as a ball mill and mixed, the metal hydride powder having an average particle size of 1 to 10 μm finer than that of the soft magnetic alloy powder is obtained. Although it is easy to crush, it is further refined, but the soft magnetic alloy powder is difficult to crush, so even if it is not a powder, the metal hydride is crushed first to become a powder, while the average particle size of the soft magnetic alloy powder changes almost Because there is nothing.
The hydride / nitridation compounded with the soft magnetic alloy powder when producing a metal nitride intercalated soft magnetic sintered alloy having a structure in which the metal nitride intervenes at the grain boundary of the soft magnetic alloy grains of the present invention. It is preferable that the amount of the hydride powder of the metal that can form a product (any one of R, Al, Li, Ca, Sr, and Mg) is in the range of 0.05 to 5% by mass. This is because even if the content is less than 0.05% by mass, the effect of increasing the resistance is not sufficient. On the other hand, if the content exceeds 5% by mass, the magnetic characteristics are greatly deteriorated, which is not preferable.
[0009]
The soft magnetic alloy powder, which is a raw material powder for producing the metal nitride intervening soft magnetic alloy of the present invention, may be a soft magnetic alloy powder produced by any of the atomizing method, electrolytic method, and reducing method. it can.
The soft magnetic alloy powder used in the method for producing a soft magnetic sintered alloy of the present invention specifically includes iron powder, Fe-Si iron-based soft magnetic alloy powder, Fe-Al iron-based soft magnetic alloy. Any one of powder, Fe-Si-Al-based iron-based soft magnetic alloy powder, Fe-Cr-based iron-based soft magnetic alloy powder, or nickel-based soft magnetic alloy powder. It is a generally known soft magnetic alloy powder, more specifically, iron powder,
Si: Fe—Si-based iron-based soft magnetic alloy powder containing 0.1 to 10%, the balance being Fe and inevitable impurities,
Fe: Si—Al-based iron-based soft magnetic alloy powder containing Si: 0.1 to 10%, Al: 0.1 to 20%, the balance being Fe and inevitable impurities,
Al: Fe—Al-based iron-based soft magnetic alloy powder containing 0.1 to 20%, the balance being Fe and inevitable impurities,
Fe: Cr-based iron containing 1 to 20% of Cr, optionally containing one or two of Al: 5% or less, Si: 5% or less, the balance being Fe and inevitable impurities Base soft magnetic alloy powder, or
Ni: 35 to 85%, if necessary, Mo: 5% or less, Cu: 5% or less, Cr: 2% or less, Mn: 0.5% or less, one or two or more types, Metal soft magnetic powders such as nickel-based soft magnetic alloy powders with the balance being Fe and inevitable impurities can be used.
[0010]
A sintered body obtained by sintering the compacted body in a non-oxidizing atmosphere at a temperature of 1000 to 1300 ° C. can form hydrides and nitrides by hydride dehydrogenation at the grain boundaries of soft magnetic alloy grains. A metal intervening structure is formed. The non-oxidizing atmosphere at this time is a vacuum or an inert gas atmosphere, and a temperature of 1000 to 1300 ° C. at this time is a temperature range generally known as a temperature range in which the metal hydride is dehydrogenated.
The hydride / nitride-forming metal intervening in the grain boundary of the dehydrogenated sintered body is easy to form a nitride, and if the sintered body is subsequently subjected to nitriding treatment, the hydrogen present in the grain boundary of the sintered body The nitride / nitride-forming metal is nitrided to form a metal nitride phase up to the inner center of the sintered body. The nitriding conditions at this time are performed by heating in a nitrogen atmosphere at a temperature of 1000 to 1300 ° C. for 1 to 3 hours and then maintaining the same atmosphere at 300 to 800 ° C. for 3 to 10 hours.
[0011]
The metal capable of forming hydride / nitride is any one of R, Al, Li, Ca, Sr, and Mg. However, R is any one of Y, Ce, La, Pr, Nd, Sm, Gd, Ho, Er, Yb, and Lu. Therefore, the hydride / nitride-forming metal hydride powder, which is a raw material powder for producing the metal nitride-mediated soft magnetic alloy of the present invention, specifically includes a hydride R powder, a hydride Al powder, One of hydrogenated Li powder, hydrogenated Ca powder, hydrogenated Sr powder, and hydrogenated Mg powder. Among the hydrogenated R powders, the hydrogenated Y powder, the hydrogenated Ce powder, the hydrogenated La powder, the hydrogenated Nd powder, and the hydrogenated Sm powder are the most readily available and therefore easy to use.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
As raw material powders, all have an average particle size: 60 μm, all manufactured by gas atomization, pure iron powder,
Si: Fe-Si-based iron-based soft magnetic alloy powder containing 3%, the balance being Fe and inevitable impurities,
Fe—Si—Al-based iron-based soft magnetic alloy powder containing Si: 3%, Al: 3%, the balance being Fe and inevitable impurities,
Al: Fe—Al-based iron-based soft magnetic alloy powder containing 5%, the balance being Fe and inevitable impurities,
Fe: Cr-based iron-based soft magnetic alloy powder containing 17% of Cr, the balance being Fe and inevitable impurities,
A nickel-based soft magnetic alloy powder containing Ni: 20% and the balance being Fe and inevitable impurities was prepared. Further, all of them have an average particle size: 3 μm, Al powder, hydrogenated Li powder, hydrogenated Ca powder, hydrogenated Sr powder, hydrogenated Mg powder, hydrogenated Y powder, hydrogenated Ce powder, hydrogenated La powder. Hydrogenated Nd powder and hydrogenated Sm powder were prepared.
[0013]
Example 1
Hydride powder was blended in the ratio shown in Table 1 into the pure iron powder prepared earlier, charged into a ball mill, and the rotational speed: 80 r. p. m. The mixture was pulverized and mixed by rotating for 5 hours to prepare a mixed powder. By applying a molding pressure of 6 ton / cm 2 to the obtained mixed powder, a consolidated body having dimensions of 40 mm in length, 10 mm in width, and 5 mm in thickness was molded, and the obtained compact is shown in Table 2. Sintering in an atmosphere and temperature, and then nitriding under the conditions shown in Table 2 to produce a metal nitride intervening soft magnetic sintered alloy in which a metal nitride intervenes at grain boundaries. And Comparative Methods 1-6 were performed.
For comparison, a conventional AlN-coated soft magnetic powder in which colloidal AlN is coated on the surface of pure iron powder is prepared. By applying a molding pressure of 6 ton / cm 2 to this conventional powder, the length is 40 mm, the width is 10 mm, By forming a compact having a thickness of 5 mm and sintering the resulting compact in a nitrogen atmosphere, a metal nitride-mediated soft magnetic sintered alloy in which AlN is interposed at the grain boundary is conventionally produced. Method 1 was performed.
[0014]
Relative density and bending strength were measured for the metal nitride-mediated soft magnetic sintered alloys obtained by the present invention methods 1 to 10, comparative methods 1 to 6 and the conventional method 1, and the results are shown in Table 2, Saturation magnetic flux density B 10K (B 10K indicates the value of magnetic flux density when an external magnetic field of 10 kA is applied; the same applies hereinafter), specific resistance and frequency: The relative permeability at a high frequency of 100 KHz is measured, and the result is shown It was shown in 2.
[0015]
[Table 1]
[0016]
[Table 2]
[0017]
From the results shown in Tables 1 and 2, the metal nitride-mediated soft magnetic sintered alloy produced by the inventive methods 1 to 10 is relatively in comparison with the metal nitride-mediated soft magnetic sintered alloy produced by the conventional method 1. It can be seen that the density, strength, and magnetic properties are all excellent. However, it can be seen that the metal nitride intervening soft magnetic sintered alloys produced by Comparative Methods 1 to 6 exhibit unsatisfactory characteristics in at least one of the above characteristics.
[0018]
Example 2
Hydride powder was blended in the proportion shown in Table 3 into the Fe-Si-based iron-based soft magnetic alloy powder prepared earlier, charged in a ball mill, and the rotation speed: 80 r. p. m. The mixture was pulverized and mixed by rotating for 5 hours to prepare a mixed powder. By applying a molding pressure of 6 ton / cm 2 to the obtained mixed powder, a consolidated body having dimensions of 40 mm in length, 10 mm in width, and 5 mm in thickness was molded, and the obtained compact is shown in Table 4. Sintering in the atmosphere and temperature, and then nitriding under the conditions shown in Table 4 to produce metal nitride intervening soft magnetic sintered alloys in which metal nitride intervenes at the grain boundaries. And Comparative Methods 7-12 were carried out.
For comparison, a conventional AlN-coated soft magnetic powder in which colloidal AlN is coated on the surface of an Fe-Si-based iron-based soft magnetic alloy powder is prepared, and this conventional powder is longitudinally applied by applying a molding pressure of 6 ton / cm 2. : Compacted body having dimensions of 40 mm, width: 10 mm, thickness: 5 mm, and sintered the resulting compacted body in a nitrogen atmosphere, whereby metal nitride mediated soft magnetic sintering with AlN intervening at grain boundaries Conventional method 2 was performed by making gold.
[0019]
Relative density and bending strength were measured for the metal nitride-mediated soft magnetic sintered alloys obtained by the present invention methods 11 to 20, comparative methods 7 to 12 and conventional method 2, and the results are shown in Table 4, Saturated magnetic flux density B 10K , specific resistance and frequency: The relative permeability at a high frequency of 100 KHz was measured, and the results are shown in Table 4.
[0020]
[Table 3]
[0021]
[Table 4]
[0022]
From the results shown in Tables 3 to 4, the metal nitride-mediated soft magnetic sintered alloy produced by the inventive methods 11 to 20 is relatively in comparison with the metal nitride-mediated soft magnetic sintered alloy produced by the conventional method 2. It can be seen that the density, strength, and magnetic properties are all excellent. However, it can be seen that the metal nitride-mediated soft magnetic sintered alloy produced by Comparative Methods 7 to 12 exhibits unsatisfactory characteristics in at least one of the above characteristics.
[0023]
Example 3
Hydride powder was blended with the Fe-Si-Al-based iron-based soft magnetic alloy powder prepared in the ratio shown in Table 5 and charged into a ball mill, and the rotational speed was 80 r. p. m. The mixture was pulverized and mixed by rotating for 4 hours to prepare a mixed powder. By applying a molding pressure of 6 ton / cm 2 to the obtained mixed powder, a compact having dimensions of 40 mm in length, 10 mm in width, and 5 mm in thickness was formed. Table 6 shows the resulting compact. Sintering in the atmosphere and temperature, and then nitriding under the conditions shown in Table 6 to produce metal nitride intervening soft magnetic sintered alloys in which metal nitride intervenes at grain boundaries. And comparative methods 13-18 were carried out.
For comparison, a conventional AlN-coated soft magnetic powder in which colloidal AlN is coated on the surface of an Fe-Si-Al-based iron-based soft magnetic alloy powder is prepared, and a molding pressure of 6 ton / cm 2 is applied to the conventional powder. By forming a compact with a dimension of 40 mm in length, 10 mm in width, and 5 mm in thickness, and sintering the resulting compact in a nitrogen atmosphere, metal nitride-mediated soft magnetism in which AlN is present at the grain boundaries Conventional method 3 was performed by making a sintered alloy.
[0024]
Relative density and bending strength were measured for the metal nitride-mediated soft magnetic sintered alloys obtained by the present invention methods 21-30, comparative methods 13-18, and the conventional method 3, and the results are shown in Table 6, Saturated magnetic flux density B 10K , specific resistance and frequency: The relative permeability at a high frequency of 100 KHz was measured, and the results are shown in Table 6.
[0025]
[Table 5]
[0026]
[Table 6]
[0027]
From the results shown in Tables 5 to 6, the metal nitride-mediated soft magnetic sintered alloy produced by the inventive methods 21 to 30 is relatively in comparison with the metal nitride-mediated soft magnetic sintered alloy produced by the conventional method 3. It can be seen that the density, strength, and magnetic properties are all excellent. However, it can be seen that at least one of the above characteristics of the metal nitride-mediated soft magnetic sintered alloy produced by Comparative Methods 13 to 18 exhibits unsatisfactory characteristics.
[0028]
Example 4
Hydride powder was blended with the Fe-Al based iron-based soft magnetic alloy powder prepared in the ratio shown in Table 7 and charged into a ball mill. p. m. The mixture was pulverized and mixed by rotating for 4.5 hours to prepare a mixed powder. By applying a molding pressure of 6 ton / cm 2 to the obtained mixed powder, a consolidated body having dimensions of 40 mm in length, 10 mm in width, and 5 mm in thickness was molded, and the obtained compact is shown in Table 8. Sintering at atmosphere and temperature, and then nitriding under the conditions shown in Table 8 to produce a metal nitride intervening soft magnetic sintered alloy in which metal nitride intervenes at grain boundaries. And Comparative Methods 19-24 were performed.
For comparison, a conventional AlN-coated soft magnetic powder in which colloidal AlN is coated on the surface of an Fe-Al-based iron-based soft magnetic alloy powder is prepared, and this conventional powder is longitudinally applied by applying a molding pressure of 6 ton / cm 2. : Compacted body having dimensions of 40 mm, width: 10 mm, thickness: 5 mm, and sintered the resulting compacted body in a nitrogen atmosphere, whereby metal nitride mediated soft magnetic sintering with AlN intervening at grain boundaries Conventional method 4 was performed by making gold.
[0029]
Relative density and bending strength were measured for the metal nitride-mediated soft magnetic sintered alloys obtained by the inventive methods 31 to 40, comparative methods 19 to 24 and the conventional method 4, and the results are shown in Table 8, Saturated magnetic flux density B 10K , specific resistance and frequency: The relative permeability at a high frequency of 100 KHz was measured, and the results are shown in Table 8.
[0030]
[Table 7]
[0031]
[Table 8]
[0032]
From the results shown in Tables 7 to 8, the metal nitride-mediated soft magnetic sintered alloy produced by the inventive methods 31 to 40 is relatively in comparison with the metal nitride-mediated soft magnetic sintered alloy produced by the conventional method 4. It can be seen that the density, strength, and magnetic properties are all excellent. However, it can be seen that the metal nitride intervening soft magnetic sintered alloys produced by the comparative methods 19 to 24 exhibit unsatisfactory characteristics in at least one of the above characteristics.
[0033]
Example 5
Hydride powder was blended in the proportion shown in Table 9 into the Fe—Cr-based iron-based soft magnetic alloy powder prepared earlier, charged in a ball mill, and the rotational speed: 80 r. p. m. The mixture was pulverized and mixed by rotating for 6 hours to prepare a mixed powder. By applying a molding pressure of 6 ton / cm 2 to the obtained mixed powder, a consolidated body having dimensions of 40 mm in length, 10 mm in width, and 5 mm in thickness was molded, and the obtained compact is shown in Table 10. Sintering in the atmosphere and temperature, and then nitriding under the conditions shown in Table 10 to produce metal nitride intervening soft magnetic sintered alloys in which metal nitride intervenes at grain boundaries. And Comparative Methods 25-30 were performed.
For comparison, a conventional AlN-coated soft magnetic powder in which colloidal AlN is coated on the surface of an Fe—Cr-based iron-based soft magnetic alloy powder is prepared, and this conventional powder is longitudinally applied by applying a molding pressure of 6 ton / cm 2. : Compacted body having dimensions of 40 mm, width: 10 mm, thickness: 5 mm, and sintered the resulting compacted body in a nitrogen atmosphere, whereby metal nitride mediated soft magnetic sintering with AlN intervening at grain boundaries Conventional method 5 was performed by making gold.
[0034]
Relative density and bending strength were measured for the metal nitride-mediated soft magnetic sintered alloys obtained by the present invention methods 41 to 50, comparative methods 25 to 30 and the conventional method 5, and the results are shown in Table 10, Saturated magnetic flux density B 10K , specific resistance and frequency: The relative permeability at a high frequency of 100 KHz was measured, and the results are shown in Table 10.
[0035]
[Table 9]
[0036]
[Table 10]
[0037]
From the results shown in Tables 9 to 10, the metal nitride-mediated soft magnetic sintered alloy produced by the inventive methods 41 to 50 is relatively in comparison with the metal nitride-mediated soft magnetic sintered alloy produced by the conventional method 5. It can be seen that the density, strength, and magnetic properties are all excellent. However, it can be seen that the metal nitride-containing soft magnetic sintered alloy produced by Comparative Methods 25 to 30 exhibits unsatisfactory characteristics in at least one of the above characteristics.
[0038]
Example 6
The nickel-based soft magnetic alloy powder prepared above was mixed with hydride powder in the proportions shown in Table 11 and charged into a ball mill. p. m. The mixture was pulverized and mixed by rotating for 5.5 hours to prepare a mixed powder. By applying a molding pressure of 6 ton / cm 2 to the obtained mixed powder, a consolidated body having dimensions of 40 mm in length, 10 mm in width, and 5 mm in thickness was molded, and the obtained compact is shown in Table 12. Sintering in the atmosphere and temperature, and then nitriding under the conditions shown in Table 12 to produce metal nitride intervening soft magnetic sintered alloys in which metal nitride intervenes at grain boundaries, thereby producing the inventive methods 51-60 And Comparative Methods 31-36 were performed.
For comparison, a conventional AlN-coated soft magnetic powder in which colloidal AlN is coated on the surface of a nickel-based soft magnetic alloy powder is prepared, and this conventional powder is subjected to a forming pressure of 6 ton / cm 2 to obtain a length of 40 mm and a width of A compact body having a size of 10 mm and a thickness of 5 mm is formed, and the resulting compact body is sintered in a nitrogen atmosphere to produce a metal nitride-mediated soft magnetic sintered alloy in which AlN is interposed at the grain boundaries. Thus, the conventional method 6 was carried out.
[0039]
Relative density and bending strength were measured for the metal nitride-containing soft magnetic sintered alloys obtained by the present invention methods 51-60, comparative methods 31-36 and conventional method 6, and the results are shown in Table 12, Saturated magnetic flux density B 10K , specific resistance and frequency: The relative permeability at a high frequency of 100 KHz was measured, and the results are shown in Table 12.
[0040]
[Table 11]
[0041]
[Table 12]
[0042]
From the results shown in Tables 11 to 12, the metal nitride-mediated soft magnetic sintered alloy produced by the inventive methods 51 to 60 is relatively in comparison with the metal nitride-mediated soft magnetic sintered alloy produced by the conventional method 6. It can be seen that the density, strength, and magnetic properties are all excellent. However, it can be seen that the metal nitride-mediated soft magnetic sintered alloy produced by the comparative methods 31 to 36 exhibits an unsatisfactory characteristic in at least one of the above characteristics.
[0043]
【The invention's effect】
The present invention can provide a metal nitride intervening soft magnetic sintered alloy with high density, excellent mechanical strength, and high high-frequency relative permeability, and has excellent effects in the electrical and electronic industries. .
