CN1200192A - 复合磁体和使用该复合磁体的电磁干扰抑制体 - Google Patents

复合磁体和使用该复合磁体的电磁干扰抑制体 Download PDF

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CN1200192A
CN1200192A CN97191188A CN97191188A CN1200192A CN 1200192 A CN1200192 A CN 1200192A CN 97191188 A CN97191188 A CN 97191188A CN 97191188 A CN97191188 A CN 97191188A CN 1200192 A CN1200192 A CN 1200192A
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吉田荣吉
小野典彦
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Abstract

在有机粘结剂中分散扁平状软磁粉末而构成的复合磁体中,通过使用生物分解性塑料作为该有机粘结剂,提供没有因废弃而导致的公害担心的复合磁体。作为生物分解性塑料,可使用微生物系、化学合成系、天然高分子系中的任一种。

Description

复合磁体和使用该复合磁体的电磁干扰抑制体
本发明涉及适用于在电子仪器中抑制电磁干扰的复合磁体。
在电子仪器中，存在由来自外部的电磁波引起的故障，或者仪器本身发射的电磁波对外部仪器造成的故障，亦即所谓的电磁干扰成为问题。此电磁干扰问题随着电子仪器的高频率化、小型化、非市电供电化(停电力化)而更为显著。
为了抑制这种电磁干扰，以往是使用导体板制成的电磁屏蔽。然而，导体板虽然可以阻断电磁波的透过，但是却存在因反射引起的二次发射的问题。亦即，虽然保护电子仪器不受来自仪器外部的电磁波的影响，但是因反射引起的二次发射对外部仪器造成影响。而且，来自仪器内部的电磁波在仪器内部反射，对同一仪器内的其它电子部件施加不利影响。而且，这种不需要的电磁波，特别是在高频仪器中，其成分遍及较宽的频率范围，也存在不少难以确定与电磁故障相关的频率成分的情况。
因此，为了抑制这种电磁干扰，期望有在较宽频率吸收无用电磁波的材料。
作为响应这种期望的材料，特开平7-212079号公报提供了一种复合磁体，是在有机粘结剂中分散具有形状各向异性的软磁粉末。这种复合磁体是在电磁波的吸收中，利用通过难磁化体粉末的复数磁性共振发现和类推的遍及数十MHz至数GHZ的磁性损耗。
所述特开平7-212079号公报公开了一种电磁干扰抑制体，层叠该复合磁体和导体，由导体层阻断电磁波的透过，同时由复合磁体吸收电磁波，防止电磁波的侵入反射。
另一方面，近年来，对工业上的多种制品日益增强的期望是废弃处理时不产生有害物质，自然完全分解不留残渣，或者回收性强等。但是，所述的电磁干扰抑制体和作为该材料的复合磁体，未全面考虑这些期望。
本发明的目的是为了解决这些问题，提供一种可以保证废弃处理时的安全性、自然分解、而且回收性强的复合磁体和使用该复合磁体的电磁干扰抑制体。
如权利要求1所述，本发明提供一种复合磁体，在有机粘结剂中分散扁平状软磁粉末而构成，其特征在于所述有机粘结剂是生物分解性塑料。
本发明的复合磁体的实施例如从属权利要求2、3和4所述。
而且，如权利要求4所述，本发明提供由所述复合磁体和导电性材料构成的电磁干扰抑制体。
图1是展示本发明的复合磁体的基本构成的侧视剖面图。
图2是在使用图1所示复合磁体的电磁干扰抑制体的特性评价中使用的评价装置的概略构成的透视图。
图3作为与图1所示复合磁体的磁各向异性不同相关的实验样品的磁特性，展示了研究导磁率与频率的特性的结果。
以下，参照附图详细说明本发明的复合磁体和采用该磁体的电磁干扰抑制体的实施例。
图1是展示本发明的复合磁体3的基本构成的侧视剖面图。此复合磁体3是在有机粘结剂中分散扁平状软磁粉末2而构成的保持期望的磁特性的绝缘性软磁体，有机粘结剂1使用生物分解性塑料。就生物分解性塑料而言，有微生物系、化学合成系、天然高分子系，其中任何一种制品均可使用。而且，软磁粉末2，可以是铁粉、或者至少含有铁和硅的合金粉末。
此复合磁体3，由于占相当部分的体积的生物分解性塑料的有机粘结剂1，随着废弃处理时的时间推移易于分解，而且作为主要构成因素之一的软磁粉末2中，使用铁粉或含铁和硅的合金粉末保证了安全性，所以便于废弃处理或回收使用。
关于微生物系生物分解性塑料，市售的有商品名为生物极点(バイオポ-ル)的β-羟基正丁酸和β-羟基戊酸制成的微生物产生的共聚合聚酯。另一方面，已知开发中的有通过微生物和产碱杆菌属细菌产生的生物聚酯，由一种乙酸菌生产的生物聚合物，作为有效利用污水处理的在微生物菌体内生成生物分解性聚酯等。
而且，关于化学合成系生物分解性塑料，市售的有以乙二酸和脂肪族二羧酸作为原料通过缩聚合法合成的脂肪族聚酯(商品名是ビオノ-レ)，通过乳酸的环状2量体的开环聚合的生成物(商品名是ラクテイ)，由脂肪族线状聚酯制成的高分子量聚己内酯(商品名是ブラクセル-H)，脂肪族系聚酯树脂聚己内酯(商品名是ト-ン)等。另一方面，正在开发中的已知有以脂肪族系酯为基的化学合成而产生的共聚合体生成物，由生物分解性纤维的制成物等。
再有，关于天然高分子系生物分解性塑料，市售的有与以淀粉为主要成分的改性PVA等的聚合物混合体(商品名是マタ-ビ-)，在淀粉质主成分中添加天然或合成添加剂的生成物(商品名是ノボン)等。另一方面，正在开发中的已知有脱乙酰壳多糖、纤维素、淀粉的共聚合体的制成物，在聚己内酯中添加淀粉的生成物等。
但是，通过使此复合磁体3的磁特性具有在互不相同的频率区域出现的多个磁共振，而在遍及宽带域的频率区域获得期望的磁性损耗特性。
亦即，这种复合磁体3除了可以保证上述废弃处理时的安全性并容易回收使用外，还具有期望的高频导磁率特性，而且提供非良好导电性，作为电波吸收体对空间阻抗的调整也是有效的。
把这种复合磁体3加工成薄板状并在金属制成的薄板上层叠，由此可以制成以电磁干扰抑制为目的的电磁干扰抑制体。但是，在这种电磁干扰抑制体中，在复合磁体3的不同频率区域出现的复数磁性共振之中，在最低频率区域出现的磁性共振希望处于比期望的电磁干扰抑制频率区域下限还低的频率区域。
在复合磁体3的表面形成介电层，使其夹着金属网等导电支持体多重层叠，获得电磁干扰抑制体。在此层叠构造中，具有降低涡流损耗的效果。在高频电子仪器的应做电磁干扰抑制之处实际设置这种电磁干扰抑制体的情况下，切成适当大小使用。
如此制作的电磁干扰抑制体的特性，可以用图2所示的特性评价用的评价装置来测试。这种评价装置配备有在铜板8上层叠复合磁体3而构成的电磁干扰抑制体10的复合磁体3一侧附近，与电磁场波源用发生器6连接的微型环形天线4，和与网络分析器等电磁场强度测试仪7连接的微型环形天线5。而且，作为电磁干扰抑制体10，使用以铜板8做衬的厚2mm、一边长20cm的复合磁体3，微型环形天线4、5的环直径为1.5mm。
使用这种评价装置，从电磁场波源用发生器6通过微型环形天线4，向电磁干扰抑制体10发射预定强度的电磁波，通过微型环形天线5由电磁场强度测试仪7测试与电磁干扰抑制体10之间的结合电平，由此可以评价电磁干扰抑制体10的性能。
以下对这种复合磁体3的制备工序、磁特性和电磁干扰抑制性能的评价做具体说明。
制造复合磁体3时，准备最初通过雾化法制备的磁致伸缩常数λ不同的多种铁-硅合金粉末和铁铝硅合金粉末，采用主式球磨(アトライタ)和喷丸研磨(ピンミル)在各种条件下对粉末进行粉碎、延展、扯裂加工，然后一边在碳氢化合物系有机溶剂中导入氧分压为35％的氮-氧混合气体，一边搅拌8小时，进行液相中的缓慢氧化处理后，进行分级处理获得磁各向异性不同的多种粉末。对由此获得的粉末做表面分析，结果明确地证实了金属氧化物的生成，证实了样品粉末表面存在氧化被膜。
而且，对经粉碎、延展、扯裂加工处理的铁-硅合金粉末和铁铝硅合金粉末进行减压干燥，在氧分压为20％的氮-氧混合气体气氛中对粉末进行气相缓慢氧化的样品，在其表面检测出金属氧化物，可以作为复合磁体3使用，证实了通过液相中缓慢氧化法或者气相中缓慢氧化法，可以制备至少其表面氧化的软磁粉末。
再有，作为关于复合磁体3的制造和磁特性的具体验证例，列举以下的样品1～3作为展示。但是，在对这里的各样品的磁特性的测试中，使用加工成圆环形状的复合磁体样品，把这些样品插入形成1匝线圈的测试装置中，通过测量阻抗求得实数导磁率μ’和磁共振频率fr。
(样品1)
按扁平状软磁体(Fe-Al-Si合金)微粉末A[平均粒径：φ＝20μm×0.3μmt，磁致伸缩大小：+0.72，退火处理：无]为95重量份，作为有机粘结剂1的上述微生物系生物分解性塑料、化学合成系生物分解性塑料、天然高分子系生物分解性塑料的商品化中的任何一种为8重量份，固化剂(异氰酸酯化合物)为2重量份，溶剂(溶纤剂(セルソルブ)系混合溶剂)为40重量份配合，调和成软磁性浆料，利用刮刀法用这些浆料制膜，施加热压后在85℃进行24小时的固化，获得样品1。
采用扫描型电子显微镜分析此样品1后，发现粒子排列方向是样品膜面内方向。而且，样品1的粉末填充率是30％，实数导磁率μ’是14，磁共振频率fr是50MHz。
而且，在H＝200奥斯特时，磁致伸缩量值为d1/1×10-6。
(样品2)
按扁平状软磁体(Fe-Al-Si合金)微粉末B[平均粒径：φ＝20μm×0.3μmt，磁致伸缩大小：+0.72，退火处理条件：650℃×2小时]为95重量份，作为有机粘结剂1的上述微生物系生物分解性塑料、化学合成系生物分解性塑料、天然高分子系生物分解性塑料的商品化中的任何一种为8重量份，固化剂(异氰酸酯化合物)为2重量份，溶剂(溶纤剂(セルソルブ)系混合溶剂)为40重量份配合，调和成软磁性浆料，利用刮刀法用这些浆料制膜，施加热压后在85℃进行24小时的固化，获得样品2。
采用扫描型电子显微镜分析此样品2后，发现粒子排列方向是样品膜面内方向。而且，样品2的粉末填充率是29％，实数导磁率μ’是16，磁共振频率fr是30MHz。
(样品3)
按扁平状软磁体(Fe-Al-Si合金)微粉末E[平均粒径：φ＝20μm×0.4μmt，磁致伸缩大小：几乎为0]为95重量份，作为有机粘结剂1的上述微生物系生物分解性塑料、化学合成系生物分解性塑料、天然高分子系生物分解性塑料的商品化中的任何一种为8重量份，固化剂(异氰酸酯化合物)为2重量份，溶剂(溶纤剂(セルソルブ)系混合溶剂)为40重量份配合，调和成软磁性浆料，利用刮刀法用这些浆料制膜，施加热压后在85℃进行24小时的固化，获得样品3。
采用扫描型电子显微镜分析此样品3后，发现粒子排列方向是样品膜面内方向。而且，样品3的粉末填充率是31％，实数导磁率μ’是17，磁共振频率fr是25MHz。
图3中分别由曲线C1、C2和C3展示了这些样品1、样品2和样品3与频率f(MHz)对应的实数导磁率(μ’)的测试值。
从该图可知，使用具有正磁致伸缩常数λ的磁性粉末的样品1的磁共振频率fr为最高。而且，磁致伸缩常数λ几乎为0的样品3的实数导磁率μ’的值最大。关于曲线2所示的样品2，是把样品1所用的磁性粉末施加退火处理后用做原料粉末，但是无论是磁共振频率fr还是实数导磁率μ’的值均处于样品1和样品3的中间位置。
关于生物分解性塑料，从这些结果可断定采用属于何种分类的制品均不影响磁特性，可以作为复合磁体的有机粘结剂利用。而且，关于磁特性断定使磁致伸缩常数λ不为0值，再通过退火改变残留的磁致伸缩量，则可把导磁率的频率特性控制在较宽范围。
如上所述，根据本发明的复合磁体和使用该磁体的电磁干扰抑制体，由于在向有机粘结剂中分散扁平状软磁粉末而构成的保持所期望的磁特性的作为绝缘性软磁体的复合磁体中的有机粘结剂中使用生物分解性塑料，软磁粉末采用铁粉、或者至少含有铁和硅的合金粉末，所以可保证废弃处理时的安全性，回收性强。

Claims (5)

1.一种复合磁体，在有机粘结剂中分散扁平状软磁体粉末而构成，其特征在于，所述有机粘结剂是生物分解性塑料。
2.根据权利要求1的复合磁体，其特征在于，所述生物分解性塑料是微生物系、化学合成系、天然高分子系中的任一种。
3.根据权利要求1或2的复合磁体，其特征在于，所述软磁粉末是铁粉、或者至少含有铁和硅的合金粉末。
4.一种电磁干扰抑制体，其特征在于，由权利要求1～3中的任一项所记载的复合磁体和导电材料构成。
5.根据权利要求4的电磁干扰抑制体，其特征在于，所述复合磁体具有在互不相同的频率区域出现的多个磁共振。
CNB971911886A 1996-09-06 1997-09-05 复合磁体和使用该复合磁体的电磁干扰抑制体 Expired - Fee Related CN1149592C (zh)

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CN102744398B (zh) * 2005-09-06 2015-01-14 株式会社三德 多孔铁粉、其制造方法及电波吸收体
CN105744818A (zh) * 2016-02-03 2016-07-06 中电海康集团有限公司 一种柔性磁屏蔽和抗辐照薄膜

Families Citing this family (6)

* Cited by examiner, † Cited by third party
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DE10106172A1 (de) * 2001-02-10 2002-08-29 Bosch Gmbh Robert Verfahren zur Herstellung eines Formteils aus einem weichmagnetischen Verbundwerkstoff
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JP2011129798A (ja) * 2009-12-21 2011-06-30 Mitsumi Electric Co Ltd 高周波用磁性材料、高周波デバイス及び磁性粒子
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Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5275880A (en) * 1989-05-17 1994-01-04 Minnesota Mining And Manufacturing Company Microwave absorber for direct surface application
JPH05251222A (ja) * 1992-03-05 1993-09-28 Seiko Epson Corp 樹脂結合型磁石
FI117224B (fi) * 1994-01-20 2006-07-31 Nec Tokin Corp Sähkömagneettinen häiriönpoistokappale, ja sitä soveltavat elektroninen laite ja hybridimikropiirielementti

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CN102744398B (zh) * 2005-09-06 2015-01-14 株式会社三德 多孔铁粉、其制造方法及电波吸收体
CN105744818A (zh) * 2016-02-03 2016-07-06 中电海康集团有限公司 一种柔性磁屏蔽和抗辐照薄膜

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