JPH1059766A - Production of ferrite granule for compound - Google Patents
Production of ferrite granule for compoundInfo
- Publication number
- JPH1059766A JPH1059766A JP8227423A JP22742396A JPH1059766A JP H1059766 A JPH1059766 A JP H1059766A JP 8227423 A JP8227423 A JP 8227423A JP 22742396 A JP22742396 A JP 22742396A JP H1059766 A JPH1059766 A JP H1059766A
- Authority
- JP
- Japan
- Prior art keywords
- ferrite
- sintered
- granules
- compound
- particle size
- 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.)
- Pending
Links
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
- H01F1/34—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 non-metallic substances, e.g. ferrites
- H01F1/36—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 non-metallic substances, e.g. ferrites in the form of particles
Landscapes
- Chemical & Material Sciences (AREA)
- Dispersion Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Hard Magnetic Materials (AREA)
- Soft Magnetic Materials (AREA)
- Magnetic Ceramics (AREA)
Abstract
Description
【0001】[0001]
【発明の属する技術分野】本発明は、有機あるいは無機
の各種の結合材と混合して所定形状の電波吸収体に成形
するための、コンパウンド用のフェライト粉粒物の製造
方法に関するものである。このコンパウンドは、電波暗
室の内壁面や高層建築物の外壁材などの電波吸収体の製
造に広く利用できる。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a ferrite powder for a compound, which is mixed with various organic or inorganic binders to form a radio wave absorber having a predetermined shape. This compound can be widely used for manufacturing radio wave absorbers such as the inner wall surface of an anechoic chamber and the outer wall material of a high-rise building.
【0002】[0002]
【従来の技術】高層建築物では、テレビ電波の反射によ
りテレビ画面にゴースト(二重像あるいは三重像)が生
じるのを防止するために、電波吸収機能を有する外壁材
が使用されている。外壁材の一例としては、内部に鉄筋
を配設し、軽量コンクリートを板状に流し込んだPC
(プレキャスト・コンクリート)パネルの片面に、金属
製の反射体を介して電波吸収体となるフェライトモルタ
ル層を形成し、そのフェライトモルタル層を外装化粧板
の下地とする構造がある。外壁面に入射した電波は一部
がフェライトモルタルで反射する。残りはフェライトモ
ルタルを透過し、反射体で反射して戻り、フェライトモ
ルタルから放射される。電波は、フェライトモルタル中
を透過する行程中、フェライトの磁気損失で減衰する。
フェライトモルタルからの放射電波と、最初の反射電波
とが正反対の波形であれば、両者は相殺されて無反射状
態を実現できる。このようにして電波の反射を低減する
のが、電波吸収機能を有する外壁材である。この外壁材
で用いるフェライトモルタル層は、例えば無機結合材で
あるセメントにフェライト粉粒物を混ぜたコンパウンド
を用いて、板状に成形し固化させたものである。2. Description of the Related Art In a high-rise building, an outer wall material having a radio wave absorbing function is used in order to prevent a ghost (double image or triple image) from being generated on a television screen due to reflection of a television wave. As an example of the outer wall material, a PC in which a reinforcing bar is disposed inside and lightweight concrete is poured into a plate shape
(Precast / Concrete) There is a structure in which a ferrite mortar layer serving as a radio wave absorber is formed on one side of a panel via a metal reflector, and the ferrite mortar layer is used as a base of an exterior decorative panel. A part of the radio wave incident on the outer wall is reflected by the ferrite mortar. The rest is transmitted through the ferrite mortar, reflected back by the reflector, and emitted from the ferrite mortar. The radio waves are attenuated by the magnetic loss of the ferrite during the transmission through the ferrite mortar.
If the radiated radio wave from the ferrite mortar and the first reflected radio wave have exactly opposite waveforms, they are canceled out and a non-reflection state can be realized. The outer wall material having a radio wave absorbing function reduces the reflection of radio waves in this manner. The ferrite mortar layer used for the outer wall material is formed into a plate shape by using, for example, a compound in which ferrite powder is mixed with cement as an inorganic binder and solidified.
【0003】また各種電子機器の電磁波環境試験(EM
I)には、電波暗室が広く使用されている。電波暗室
は、電磁的にシールドされた部屋の周囲の壁や天井、床
に電波吸収体を貼り付けて、外部から侵入する電磁波を
遮断し、内部で発生する電磁波を吸収するように構成さ
れている。ここで用いられている電波吸収体は、例えば
各種の合成樹脂やゴムなどの有機結合材とフェライト粉
粒物とを混合したコンパウンドを用いて成形したフェラ
イトパネルである。In addition, electromagnetic wave environment tests (EM) of various electronic devices
In I), an anechoic chamber is widely used. The anechoic chamber is constructed so that electromagnetic wave absorbers are attached to walls, ceilings, and floors around rooms that are electromagnetically shielded to block electromagnetic waves entering from the outside and absorb electromagnetic waves generated inside. I have. The radio wave absorber used here is, for example, a ferrite panel formed using a compound obtained by mixing an organic binder such as various synthetic resins and rubbers with ferrite particles.
【0004】電波吸収体のコンパウンドとして使用され
ているフェライト粉粒物は、使用する結合材の種類や混
合比率、成形方法、必要な電波吸収特性などによって異
なるが、一般に粒径0.01〜10mm程度の範囲から選
ばれる。従来、このようなフェライト粉粒物は、通常の
フェライト焼結品とほぼ同様の複雑な工程を経て製造し
ている。その製造工程の典型例を図2に示す。フェライ
トの原材料(酸化鉄及び各種の金属酸化物や金属炭酸塩
など)を所定のモル比に秤量し機械的に混合した後、ま
ず仮焼し粉砕する。仮焼は焼結温度よりも低い温度で行
っており、原料の熱分解(焼結中に分解ガスが極力発生
しないようにする)、成分の均質化、焼結性の向上(適
度の粒子サイズに粒成長を起こさせる)などのために必
要とされる。仮焼品の粉砕は、凝集をくずして粒径を調
節し、適度の焼結性をもった粉末を製造するためであ
る。次に、仮焼粉砕品を造粒(粒径100μm程度)
し、得られたフェライト顆粒を用いて適当なブロック形
状にプレス成形する。そして、その成形品を焼結して粉
砕し、篩別によって希望の粒径のフェライト粉粒物を取
り出す。焼結後の粉砕は、通常、粗粉砕と微粉砕の2段
階に分けて行い、希望の粒径のフェライト粉粒物の収率
が高くなるようにする。[0004] The ferrite powder used as the compound of the radio wave absorber varies depending on the kind and the mixing ratio of the binder used, the molding method, the required radio wave absorption characteristics, and the like. Selected from a range of degrees. Conventionally, such ferrite powders have been manufactured through almost the same complicated steps as ordinary ferrite sintered products. FIG. 2 shows a typical example of the manufacturing process. Raw materials of ferrite (iron oxide, various metal oxides, metal carbonates, and the like) are weighed at a predetermined molar ratio, mixed mechanically, and then calcined and pulverized. The calcination is performed at a temperature lower than the sintering temperature, so that the raw material is thermally decomposed (to minimize the generation of decomposition gas during sintering), the components are homogenized, and the sinterability is improved (moderate particle size To cause grain growth). The pulverization of the calcined product is intended to break down agglomeration, adjust the particle size, and produce a powder having appropriate sinterability. Next, the calcined and pulverized product is granulated (particle size: about 100 μm).
Then, the obtained ferrite granules are pressed into a suitable block shape. Then, the molded article is sintered and pulverized, and a ferrite powder having a desired particle diameter is taken out by sieving. The pulverization after sintering is usually performed in two stages of coarse pulverization and fine pulverization so that the yield of ferrite powder having a desired particle size is increased.
【0005】[0005]
【発明が解決しようとする課題】このように従来の製法
は、通常のフェライト製品と同様の工程を踏襲していた
ために、多段階の工程を経る必要があり、製造コストが
高くなる問題があった。またブロック状の焼結体を粉砕
することで所望の粒径に調整するために、得られる粉粒
物、特に粒径の大きなものは、角張った形状となり、コ
ンパウンドとしたときに充填効率が悪いし、また例えば
エポキシ樹脂などと混合して所定形状の型内に射出成形
するような場合にゲート(コンパウンドの通路)が詰ま
るなどのトラブルが生じ易い欠点もあった。As described above, the conventional manufacturing method follows the same process as that of a normal ferrite product, so that it is necessary to go through a multi-step process, and there is a problem that the manufacturing cost is increased. Was. Also, in order to adjust the particle size to a desired value by pulverizing the block-shaped sintered body, the obtained granules, particularly those having a large particle size, have an angular shape, and the filling efficiency is poor when compounded. In addition, for example, when the mixture is mixed with an epoxy resin or the like and injection molded into a mold having a predetermined shape, a problem such as clogging of a gate (compound passage) easily occurs.
【0006】本発明の目的は、上記のような従来技術の
欠点を解消し、製造プロセスを簡素化でき、工程的及び
コスト的不利益を解消できるコンパウンド用フェライト
粉粒物の製造方法を提供することである。An object of the present invention is to provide a method for producing a ferrite powder for a compound, which can solve the above-mentioned disadvantages of the prior art, can simplify the production process, and can eliminate disadvantages in terms of process and cost. That is.
【0007】[0007]
【課題を解決するための手段】本発明は、結合材と混合
して電波吸収体用のコンパウンドを作製するためのフェ
ライト粉粒物を製造する方法である。第1の方法では、
フェライト原材料を秤量して混合した後、仮焼及びその
後の粉砕工程を経ることなく、前記混合物を粉粒状に成
形し、それを焼結して解砕した後、篩別して規定の粒径
の焼結したフェライト粉粒物を取り出す。また第2の方
法では、フェライト原材料を秤量して混合した後、仮焼
及びその後の粉砕工程を経ることなく、前記混合物を粉
粒状に成形し、それを篩別して規定の粒径の粉粒物を取
り出し、それを焼結し解砕して、焼結したフェライト粉
粒物を得、前記篩別工程で取り除いた規定外の粒径の未
焼結粉粒物を前記混合工程に戻して混合する。いずれに
しても、従来工程における仮焼工程及びその後の粉砕工
程を行わない点に本発明の特徴がある。またフェライト
原材料の混合物を粉粒状に成形し、粉粒状のまま焼結し
て解砕する点に本発明の特徴がある。SUMMARY OF THE INVENTION The present invention is a method for producing a ferrite powder to be mixed with a binder to produce a compound for a radio wave absorber. In the first method,
After the ferrite raw materials are weighed and mixed, the mixture is formed into powder and granules without calcination and subsequent pulverization steps, which are sintered and disintegrated, then sieved and sintered to a prescribed particle size. Take out the bound ferrite powder. In the second method, after the ferrite raw materials are weighed and mixed, the mixture is formed into powder and granules without passing through a calcination and a subsequent pulverization step, and the mixture is sieved to obtain a powder or granules having a prescribed particle size. And sintering and crushing to obtain a sintered ferrite powder, and returning the unsintered powder having an irregular particle size removed in the sieving process to the mixing process, and mixing I do. In any case, the present invention is characterized in that the calcining step and the subsequent pulverizing step in the conventional step are not performed. Further, the present invention is characterized in that the mixture of the ferrite raw materials is formed into powder and granules, and the mixture is sintered and disintegrated in the powder and granules.
【0008】本発明によって製造するものはフェライト
の粉粒物であるから、焼結時に分解ガスが発生しても比
較的容易にガスが抜けるし、形状的あるいは寸法的な制
約が少ないため、収縮や変形といった問題はない。従っ
て仮焼工程を経ずに、いきなり焼結(本焼成)のみを行
っても、十分にフェライト化し、必要な特性を発現させ
うる。本発明は、この点に着目してなされたものであ
る。[0008] Since what is produced according to the present invention is a ferrite powder or granule, even if a decomposition gas is generated during sintering, the gas is released relatively easily. There is no problem such as deformation or deformation. Therefore, even if only sintering (main sintering) is performed immediately without passing through the calcination step, ferrite can be sufficiently formed and necessary characteristics can be exhibited. The present invention has been made focusing on this point.
【0009】これらの方法において、フェライト原材料
を混合する工程で、焼結助剤としてモリブデン、ビスマ
ス、あるいはバナジウムなどの酸化物の1種もしくは2
種以上を0.01〜1重量%程度添加しておくのが好ま
しい。これによって、仮焼工程を省略することによる焼
結性の低下の問題があっても、それを解消できるからで
ある。フェライトは、種々の材料系列のものが利用で
き、例えばマンガン−亜鉛系、マグネシウム−亜鉛系、
ニッケル−亜鉛系などでよいし、それらを複合したフェ
ライトでもよい。粉粒物の粒径は、使用目的や使用状況
(結合材の種類や混合割合等)などによって異なるが、
例えば0.01〜10mmの範囲から適宜選択し、1種類
もしくは2種類以上を組み合わせて用いる。In these methods, in the step of mixing ferrite raw materials, one or two of oxides such as molybdenum, bismuth, and vanadium are used as sintering aids.
It is preferable to add at least about 0.01 to 1% by weight of a seed. Thereby, even if there is a problem of a decrease in sinterability due to omitting the calcining step, it can be solved. Ferrite is available in various material series, for example, manganese-zinc system, magnesium-zinc system,
Nickel-zinc or the like may be used, or ferrite obtained by combining them may be used. The particle size of the powdered material varies depending on the purpose of use and usage conditions (type of binder, mixing ratio, etc.).
For example, it is appropriately selected from a range of 0.01 to 10 mm, and one type or a combination of two or more types is used.
【0010】[0010]
【発明の実施の形態】第1の方法は、図1のAに示すよ
うな工程フローで製造する。まずフェライト原材料(酸
化鉄及び各種金属酸化物、例えばマンガン−亜鉛系フェ
ライトの場合は、Fe2 O3 、Mn3 O4 、ZnO)を
フェライトの配合割合に応じて秤量し混合する。その混
合物を粉粒物に成形する。成形は、造粒により豆状の塊
を作製する方法、ローラーコンパクターにより板状の塊
を作製する方法、スラリーを加熱・乾燥して粉末状にす
る方法など任意の方法を採用でき、製造したい粒径に応
じて選択する。ここで、造粒により豆状の塊を作製する
方法は、例えば混合物に水を加えて攪拌していくことで
徐々に粒を大きくしていく方法であり、粒径5mm程度の
粒体が得られる。得られた粉粒状の成形品を乾燥し、焼
結する。その後、解砕し、篩別する。解砕は、焼結工程
で焼き付いた粉粒物同士を単にほぐしてばらばらにする
工程であり、いわゆる粉砕(固まりを砕いて粉粒物にす
る)とは異なる工程であり、粉砕のように長時間を要す
ることはない。これによって焼結した規定粒径のフェラ
イト粉粒物が得られる。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In a first method, manufacturing is performed according to a process flow as shown in FIG. First, ferrite raw materials (iron oxide and various metal oxides, for example, in the case of manganese-zinc ferrite, Fe 2 O 3 , Mn 3 O 4 , ZnO) are weighed and mixed according to the mixing ratio of ferrite. The mixture is formed into granules. The molding can be carried out by any method such as a method of producing a bean-like mass by granulation, a method of producing a plate-like mass by a roller compactor, and a method of heating and drying a slurry to a powder. Select according to the diameter. Here, a method of producing a bean-like mass by granulation is, for example, a method of gradually increasing the size of a mixture by adding water to the mixture and stirring the mixture, so that a granule having a particle size of about 5 mm is obtained. Can be The obtained powdery molded product is dried and sintered. Thereafter, it is crushed and sieved. Disintegration is a process of simply loosening powders and granules baked in the sintering process apart from each other, and is a process different from so-called pulverization (crushing a lump into powders). No time is required. As a result, a sintered ferrite powder having a specified particle size is obtained.
【0011】第2の方法は、図1のBに示すような工程
フローで製造する。まずフェライト原材料を秤量して混
合する。その混合物を粉粒物に成形する。成形方法は、
上記第1の方法と同様でよい。粉粒状の成形品を乾燥
し、篩別する。この篩別工程により、必要な粒径の粉粒
物のみを取り出す。粒径不良の粉粒物(粒径の大き過ぎ
るもの、及び粒径の小さ過ぎるもの)は前記混合工程に
戻して、秤量した原材料と混合する。前記篩別により得
られた規定の粒径の粉粒物のみを、次の焼結工程で焼結
させる。そして解砕する。この解砕も、焼結工程で焼き
付いた粉粒物同士を単にほぐしてばらばらにする工程で
ある。これによって焼結した規定粒径のフェライト粉粒
物が得られる。In the second method, the semiconductor device is manufactured by a process flow as shown in FIG. First, ferrite raw materials are weighed and mixed. The mixture is formed into granules. The molding method is
This may be the same as the first method. The granulated product is dried and sieved. By this sieving process, only the powder having a required particle size is taken out. The powdery material having a poor particle size (one having a too large particle size and one having a too small particle size) is returned to the mixing step and mixed with the weighed raw materials. Only the granular material having a prescribed particle size obtained by the sieving is sintered in the next sintering step. And crush. This crushing is also a step of simply loosening the powders and granules baked in the sintering step into pieces. As a result, a sintered ferrite powder having a specified particle size is obtained.
【0012】これらの工程フローでは、混合工程で必要
に応じて、例えば酸化モリブデン、酸化ビスマス、酸化
バナジウムなどを適量(0.01〜1重量%程度)加え
るのが望ましい。これらの酸化物は焼結助剤として機能
し、焼結性を改善する。最終的に得られたフェライト粉
粒物を、合成樹脂(例えばエポキシ樹脂)や合成ゴムな
どの有機結合材、あるいはセメントなどの無機結合材と
混合してコンパウンドとし、それを用いて各種の成形型
あるいは成形装置によって所定の形状に成形して電波吸
収体とする。このフェライト粉粒物は、従来技術のよう
な粉砕品ではなく、単なる解砕品であるから、成形時の
粉粒物の形状がほぼ保たれており、角の少ない丸みを帯
びた粒子形状をもつ。従って、例えば、樹脂結合材と混
ぜ合わせて射出成形するような場合、粉粒物が角張って
いないために成形機のゲートを通り易く、詰まりなどの
トラブルが発生せず、スムーズな成形が行える。In these process flows, it is desirable to add an appropriate amount (about 0.01 to 1% by weight) of, for example, molybdenum oxide, bismuth oxide, vanadium oxide or the like as necessary in the mixing step. These oxides function as sintering aids and improve sinterability. The finally obtained ferrite powder is mixed with an organic binder such as synthetic resin (eg, epoxy resin) or synthetic rubber, or an inorganic binder such as cement to form a compound. Alternatively, the electromagnetic wave absorber is formed into a predetermined shape by a forming device. The ferrite powder is not a pulverized product as in the prior art, but a crushed product. Therefore, the shape of the powder at the time of molding is substantially maintained, and has a rounded particle shape with few corners. Therefore, for example, in the case of injection molding by mixing with a resin binder, since the granular material is not square, it easily passes through the gate of the molding machine, and troubles such as clogging do not occur and smooth molding can be performed.
【0013】上記2方法のうち、特に第2の方法は、篩
別工程で粒径不良となった粉粒物の未焼結品を、混合工
程に戻すことによって再使用できるため、不良品が生じ
ず、材料使用効率が高まり、その点でもコスト低減に寄
与しうる。[0013] Of the above two methods, the second method is particularly capable of reusing a non-sintered powdery material having a particle size defect in the sieving step by returning it to the mixing step. This does not occur, and the material use efficiency increases, which can also contribute to cost reduction.
【0014】[0014]
【実施例】第2の方法により平均粒径40μm、最小粒
子径10μm、最大粒子径200μmのマンガン−亜鉛
系フェライト粉粒物を作製した。また比較のために、従
来方法によってほぼ同様の粒度分布のマンガン−亜鉛系
フェライト粉粒物を作製した。両者は全く同じ組成(F
e2 O3 :53.4モル%、MnO:36.6モル%、
ZnO:10.0モル%)であり、それは電波吸収体と
して一般的な材料組成である。本発明品は、スラリーを
加熱、乾燥して粉末状にする方法で粉粒物を成形し、1
320℃で焼結した。なお、従来品の焼結温度は130
0℃である。それらのフェライト粉粒物を用いて、フェ
ライト粉粒物が80%、合成ゴムが20%の割合で混合
してコンパウンドを作製し、そのコンパウンドを用いて
縦100mm×横100mm×厚さ6.3mmの板状に成形し
電波吸収体とした。その電波吸収体の電波吸収特性を表
1に示す。EXAMPLE A manganese-zinc ferrite powder having an average particle size of 40 .mu.m, a minimum particle size of 10 .mu.m and a maximum particle size of 200 .mu.m was prepared by the second method. For comparison, a manganese-zinc ferrite powder having substantially the same particle size distribution was prepared by a conventional method. Both have exactly the same composition (F
e 2 O 3 : 53.4 mol%, MnO: 36.6 mol%,
ZnO: 10.0 mol%), which is a general material composition for a radio wave absorber. The product of the present invention is obtained by forming a granular material by heating and drying a slurry to obtain a powder.
Sintered at 320 ° C. The sintering temperature of the conventional product is 130
0 ° C. Using these ferrite particles, a compound is prepared by mixing 80% of ferrite particles and 20% of synthetic rubber, and the compound is used, and the compound is used to be 100 mm long × 100 mm wide × 6.3 mm thick. To form a wave absorber. Table 1 shows the radio wave absorption characteristics of the radio wave absorber.
【0015】[0015]
【表1】 [Table 1]
【0016】第2の方法により平均粒径3mm、最小粒子
径0.5mm、最大粒子径10mmのマンガン−亜鉛系フェ
ライト粉粒物を作製した。また比較のために、従来方法
によってほぼ同様の粒度分布のマンガン−亜鉛系フェラ
イト粉粒物を作製した。両者が同じ組成(Fe2 O3 :
53.4モル%、MnO:36.6モル%、ZnO:1
0.0モル%)であることはいうまでもない。本発明品
は、造粒により豆状の塊にする方法で粉粒物を成形し、
1320℃で焼結した。なお、従来品の焼結温度は13
00℃である。それらを用いて、フェライト粉粒物が8
8%、セメントが12%の割合で混合したコンパウンド
を作製し、それを型に流し込んで板状の電波吸収体とし
た。その電波吸収特性を表2に示す。A manganese-zinc ferrite powder having an average particle diameter of 3 mm, a minimum particle diameter of 0.5 mm, and a maximum particle diameter of 10 mm was prepared by the second method. For comparison, a manganese-zinc ferrite powder having substantially the same particle size distribution was prepared by a conventional method. Both have the same composition (Fe 2 O 3 :
53.4 mol%, MnO: 36.6 mol%, ZnO: 1
0.0 mol%). The product of the present invention is formed into a granular material by a method of forming a bean-like mass by granulation,
Sintered at 1320 ° C. The sintering temperature of the conventional product is 13
00 ° C. Using them, the ferrite powder is
A compound in which 8% and cement were mixed at a ratio of 12% was prepared and poured into a mold to obtain a plate-shaped radio wave absorber. The radio wave absorption characteristics are shown in Table 2.
【0017】[0017]
【表2】 [Table 2]
【0018】上記の表1と表2から、本発明品は仮焼工
程及びその後の粉砕工程を省いているにもかかわらず、
それらの工程を経た従来品とほぼ同等の特性を呈するこ
とが分かった。実際に周波数に対する反射損失の特性曲
線をプロットした結果でも、製法の差による特性の差異
は殆ど生じないことが確認された。From the above Tables 1 and 2, the product of the present invention does not require the calcination step and the subsequent pulverization step.
It has been found that it exhibits almost the same characteristics as the conventional product having undergone these steps. The results of actually plotting the characteristic curve of the return loss with respect to the frequency also confirmed that there was almost no difference in the characteristics due to the difference in the manufacturing method.
【0019】本発明のようなコンパウンド用フェライト
粉粒物においては、その粒径は1種のみではなく、粒度
分布の異なる複数の種類の粉粒物が全体として適度の分
布を持つようにすることで、より一層充填され易いコン
パウンド用フェライト粉粒物が得られる。例えば、粒径
に応じて、 5mm〜2.5mm … 60% 2.5mm〜0.7mm … 30% 0.7mm以下 … 10% といった重量比率で組み合わると、充填され易い。それ
を実現するためには、それぞれの粒径のフェライト粉粒
物を製造し、それを秤量して混ぜ合わせるという方法を
採る。従って、本発明方法で上記のような粒径のフェラ
イト粉粒物を作製し、粒径毎に取り出して混ぜ合わせる
ことで、コンパウンド用として最適なフェライト粉粒物
が得られることになる。In the ferrite powder for compound as in the present invention, the particle size is not limited to one type, and a plurality of types of powder having different particle size distributions have a proper distribution as a whole. Thus, a ferrite powder or granule for a compound which is more easily filled can be obtained. For example, if they are combined in a weight ratio of 5 mm to 2.5 mm 60% 2.5 mm 0.7 mm 30% 0.7 mm or less 10% according to the particle size, filling is easy. In order to realize this, a method is adopted in which ferrite particles having respective particle diameters are manufactured, weighed and mixed. Therefore, by producing ferrite particles having the above-mentioned particle size by the method of the present invention, taking out the particles for each particle size and mixing them, an optimum ferrite particle for compound use can be obtained.
【0020】[0020]
【発明の効果】本発明によれば、上記のように仮焼工程
及びその後の粉砕工程を省略しても、コンパウンドにし
て電波吸収体を作製したときに、従来方法の複雑な工程
を経たのとほぼ同等の電波吸収性能が得られる。また仮
焼及びその後の粉砕工程がなく、焼結後の粉砕工程を必
要としないことから、製造コストを大幅に低減できる。
これらによって、工程的及びコスト的な不利益を全て解
消できる。更に、丸みを帯びたフェライト粉粒物が得ら
れるために、コンパウンドでの充填効率がよく、射出成
形の場合でも、ゲートの詰まりを防止できるし、金型等
の磨耗も抑えることができる。According to the present invention, even when the calcination step and the subsequent pulverization step are omitted as described above, when the compound is used to produce the radio wave absorber, the complicated steps of the conventional method have been passed. Approximately the same electromagnetic wave absorption performance can be obtained. Further, since there is no calcination and subsequent pulverization steps, and no pulverization step after sintering is required, the production cost can be significantly reduced.
With these, all disadvantages in terms of process and cost can be eliminated. Furthermore, since rounded ferrite particles can be obtained, the filling efficiency of the compound is good, and even in the case of injection molding, clogging of the gate can be prevented and wear of the mold and the like can be suppressed.
【0021】更に規格外の粒径のものが発生しても、そ
れを混合工程に戻してリサイクルさせる方法を採用すれ
ば、材料に無駄が生じず、その点でも材料コストの低減
に寄与しうる。Further, even if a particle having a particle size out of the standard is generated, if a method of recycling the particle by returning it to the mixing step is employed, no waste is caused in the material, which can also contribute to a reduction in material cost. .
【図1】本発明に係る製造工程の例を示す工程フロー
図。FIG. 1 is a process flowchart showing an example of a manufacturing process according to the present invention.
【図2】従来技術に係る製造工程の例を示す工程フロー
図。FIG. 2 is a process flowchart showing an example of a manufacturing process according to a conventional technique.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 稲垣 正幸 東京都港区新橋5丁目36番11号 富士電気 化学株式会社内 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masayuki Inagaki 5-36-11 Shimbashi, Minato-ku, Tokyo Inside Fuji Electric Chemical Co., Ltd.
Claims (3)
ウンドを作製するためのフェライト粉粒物を製造する方
法において、 フェライト原材料を秤量して混合した後、仮焼及びその
後の粉砕工程を経ることなく、前記混合物を粉粒状に成
形し、それを焼結して解砕した後、篩別して規定の粒径
の焼結したフェライト粉粒物を取り出すことを特徴とす
るコンパウンド用フェライト粉粒物の製造方法。1. A method for producing a ferrite powder and granules for preparing a compound for a radio wave absorber by mixing with a binder, comprising: weighing and mixing ferrite raw materials; Without passing through, the mixture is formed into granules, which are sintered and crushed, and then sieved to take out sintered ferrite granules having a prescribed particle size; Method of manufacturing a product.
ウンドを作製するためのフェライト粉粒物を製造する方
法において、 フェライト原材料を秤量して混合した後、仮焼及びその
後の粉砕工程を経ることなく、前記混合物を粉粒状に成
形し、それを篩別して規定の粒径の粉粒物を取り出し、
それを焼結し解砕して、焼結したフェライト粉粒物を
得、前記篩別工程で取り除いた規定外の粒径の未焼結粉
粒物を前記混合工程に戻して混合することを特徴とする
コンパウンド用フェライト粉粒物の製造方法。2. A method for producing a ferrite powder for producing a compound for a radio wave absorber by mixing with a binder, comprising: weighing and mixing ferrite raw materials; Without passing through, the mixture is formed into a granular form, which is sieved to take out a granular substance having a prescribed particle size,
It is sintered and crushed to obtain a sintered ferrite powder, and the unsintered powder having an irregular particle diameter removed in the sieving step is returned to the mixing step to be mixed. A method for producing a ferrite powder for a compound.
量した焼結助剤を添加して混合する請求項1又は2記載
のコンパウンド用フェライト粉粒物の製造方法。3. The method according to claim 1, wherein in the step of mixing the ferrite raw materials, a weighed sintering aid is added and mixed.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP8227423A JPH1059766A (en) | 1996-08-09 | 1996-08-09 | Production of ferrite granule for compound |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP8227423A JPH1059766A (en) | 1996-08-09 | 1996-08-09 | Production of ferrite granule for compound |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH1059766A true JPH1059766A (en) | 1998-03-03 |
Family
ID=16860622
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP8227423A Pending JPH1059766A (en) | 1996-08-09 | 1996-08-09 | Production of ferrite granule for compound |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH1059766A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2004244301A (en) * | 2003-01-23 | 2004-09-02 | Denso Corp | Piezoelectric ceramic composition, its production method, piezoelectric element, and dielectric element |
KR100982163B1 (en) | 2007-10-19 | 2010-09-14 | 티디케이가부시기가이샤 | Radio wave absorbing body |
KR20140053027A (en) | 2011-06-30 | 2014-05-07 | 모멘티브 파포만스 마테리아루즈 쟈판 고도가이샤 | Product having traceability displayed thereon and method for displaying traceability of product |
-
1996
- 1996-08-09 JP JP8227423A patent/JPH1059766A/en active Pending
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2004244301A (en) * | 2003-01-23 | 2004-09-02 | Denso Corp | Piezoelectric ceramic composition, its production method, piezoelectric element, and dielectric element |
KR100982163B1 (en) | 2007-10-19 | 2010-09-14 | 티디케이가부시기가이샤 | Radio wave absorbing body |
KR20140053027A (en) | 2011-06-30 | 2014-05-07 | 모멘티브 파포만스 마테리아루즈 쟈판 고도가이샤 | Product having traceability displayed thereon and method for displaying traceability of product |
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