JP2866986B2 - Piezoelectric ceramic composition - Google Patents
Piezoelectric ceramic compositionInfo
- Publication number
- JP2866986B2 JP2866986B2 JP2319182A JP31918290A JP2866986B2 JP 2866986 B2 JP2866986 B2 JP 2866986B2 JP 2319182 A JP2319182 A JP 2319182A JP 31918290 A JP31918290 A JP 31918290A JP 2866986 B2 JP2866986 B2 JP 2866986B2
- Authority
- JP
- Japan
- Prior art keywords
- piezoelectric ceramic
- ceramic composition
- composition
- present
- porcelain
- 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.)
- Expired - Fee Related
Links
- 239000000203 mixture Substances 0.000 title claims description 22
- 239000000919 ceramic Substances 0.000 title claims description 13
- 229910052573 porcelain Inorganic materials 0.000 claims description 8
- 229910052788 barium Inorganic materials 0.000 claims description 6
- 229910052791 calcium Inorganic materials 0.000 claims description 6
- 229910052712 strontium Inorganic materials 0.000 claims description 6
- 239000013078 crystal Substances 0.000 claims description 3
- 230000008878 coupling Effects 0.000 description 6
- 238000010168 coupling process Methods 0.000 description 6
- 238000005859 coupling reaction Methods 0.000 description 6
- 239000010955 niobium Substances 0.000 description 6
- 229910052758 niobium Inorganic materials 0.000 description 5
- 239000000843 powder Substances 0.000 description 5
- 238000010304 firing Methods 0.000 description 4
- 229910052749 magnesium Inorganic materials 0.000 description 4
- 229910052748 manganese Inorganic materials 0.000 description 4
- 238000004891 communication Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 239000010936 titanium Substances 0.000 description 3
- 229910010413 TiO 2 Inorganic materials 0.000 description 2
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 230000010287 polarization Effects 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 229910052787 antimony Inorganic materials 0.000 description 1
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000001351 cycling effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000007606 doctor blade method Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- YEXPOXQUZXUXJW-UHFFFAOYSA-N lead(II) oxide Inorganic materials [Pb]=O YEXPOXQUZXUXJW-UHFFFAOYSA-N 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 239000011812 mixed powder Substances 0.000 description 1
- 238000010295 mobile communication Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- VSZWPYCFIRKVQL-UHFFFAOYSA-N selanylidenegallium;selenium Chemical compound [Se].[Se]=[Ga].[Se]=[Ga] VSZWPYCFIRKVQL-UHFFFAOYSA-N 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- 230000005236 sound signal Effects 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
Landscapes
- Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
- Compositions Of Oxide Ceramics (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は、低損失、高減衰量のラダー型フィルタ等に
好適な圧電磁器組成物に関する。Description: TECHNICAL FIELD The present invention relates to a piezoelectric ceramic composition suitable for a low-loss, high-attenuation ladder-type filter or the like.
（従来技術） 近年、映像信号や音声信号など通信情報量の大容量化
や、自動車電話、移動体通信など通信端末の多様化に伴
い、高感度、低損失、高信頼性のフィルタが求められ、
このようなフィルタに適した圧電磁器組成物の開発が望
まれている。(Prior Art) In recent years, with the increase in the amount of communication information such as video signals and audio signals, and the diversification of communication terminals such as car phones and mobile communications, filters with high sensitivity, low loss, and high reliability have been required. ,
The development of a piezoelectric ceramic composition suitable for such a filter is desired.
従来、この種の圧電磁器組成物として、鉛（Pb）、ジ
ルコニウム（Zr）およびチタン（Ti）の複合酸化物から
なるいわゆるPZT系圧電磁器組成物が知られており、こ
のPZTに対し添加成分として錫（Sn）およびニオブ（N
b）の酸化物を添加し機械的品質係数（Qm）を高め共振
周波数の温度特性の変化を小さくした組成物が特公昭54
−34920号公報にて提案されている。Conventionally, a so-called PZT-based piezoelectric ceramic composition comprising a composite oxide of lead (Pb), zirconium (Zr) and titanium (Ti) has been known as a piezoelectric ceramic composition of this kind. Tin (Sn) and niobium (N
A composition in which the oxide of b) is added to increase the mechanical quality factor (Qm) and reduce the change in temperature characteristics of the resonance frequency is disclosed in
No. 34920.
また、上記PZTに対しアンチモン（Sb）及び錫（Sn）
の酸化物を添加することにより誘電率（εｒ）、圧電定
数を改善し、電気機械結合係数（Kp）を高めることが特
公昭54−36756号公報にて提案されている。In addition, antimony (Sb) and tin (Sn)
It has been proposed in Japanese Patent Publication No. 54-36756 to improve the dielectric constant (εr) and the piezoelectric constant and increase the electromechanical coupling coefficient (Kp) by adding an oxide of (i).
（発明が解決しようとする問題点） しかしながら、特公昭54−34920号の磁器は機械的品
質係数を高めることについて記載されるものの電気機械
結合係数（Kp）については何ら改善されておらず、特公
昭54−36756号の磁器は電気機械的結合係数（Kp）の改
善については言及されるものの機械的品質係数（Qm）に
ついてはなんら記載されていない。(Problems to be Solved by the Invention) However, although the porcelain disclosed in Japanese Patent Publication No. 54-34920 is described as enhancing the mechanical quality factor, it does not improve the electromechanical coupling factor (Kp) at all. The porcelain disclosed in JP-B-54-36756 mentions improvement of the electromechanical coupling coefficient (Kp), but does not describe any mechanical quality factor (Qm).
さらに、上記先行技術の磁器は実用上重要な特性であ
る温度変化に対する共振周波数の変化が大きいという問
題があった。これにより例えば環境変化の激しい車両搭
載用通信装置などのフィルタとして用いた場合、設定し
た送受信周波数が車内の温度変化により変動し安定した
送受信ができなくなるという問題があった。Furthermore, the prior art porcelain has a problem that the resonance frequency greatly changes with temperature change which is an important characteristic in practical use. As a result, for example, when used as a filter for a vehicle-mounted communication device or the like in which the environment changes drastically, there has been a problem that a set transmission / reception frequency fluctuates due to a temperature change in the vehicle, and stable transmission / reception cannot be performed.
（発明の目的） 本発明の目的は、上記問題点を解決し、高い機械的品
質係数Qmを有するとともに誘電率εｒが大きい低損失で
高減衰量を有するラダー型フィルタ等に適した新規な圧
電磁器組成物を提供するにある。(Object of the Invention) An object of the present invention is to solve the above problems and provide a novel piezoelectric material suitable for a ladder-type filter having a high mechanical quality factor Qm, a large dielectric constant εr, a low loss and a high attenuation. It is to provide a porcelain composition.
（問題点を解決するための手段） 本発明者等は、上記の問題点に対し検討を進めた結
果、PZT系圧電磁器組成物に対してMn、MgおよびNbの酸
化物を添加することによって、高い電気機械結合係数を
有するとともに温度サイクル前後の共振周波数の変動
（ドリフト）を小さくすることができることを知見し本
発明に至った。(Means for Solving the Problems) As a result of studying the above problems, the present inventors have found that by adding oxides of Mn, Mg and Nb to a PZT-based piezoelectric ceramic composition, It has been found that the present invention has a high electromechanical coupling coefficient and can reduce fluctuation (drift) of the resonance frequency before and after the temperature cycle.
即ち、本発明の圧電磁器組成物は下記式（１） Pb｛ZrxTiy（NbaMgbMnc）２｝O3 で表されるペロブスカイト型結晶構造からなる圧電磁器
組成物であって、 式中、x,y,zは ・・・（１） 0.42≦ｘ≦0.45 0.46≦ｙ≦0.49 0.08≦ｚ≦0.150 ｘ＋ｙ＋ｚ＝１ であり、a,b,cは、ａ＝１に対し 0.05≦ｂ≦0.30 0.20≦ｃ≦0.50 からなるもので、さらに前記組成物中、Pbの３〜15原子
％をBa、CaおよびSrから選ばれる少なくとも１種で置換
することを特徴とするものである。That is, the piezoelectric ceramic composition of the present invention is a formula (1) Pb {Zr x Ti y (Nb a Mg b Mn c) 2} piezoelectric ceramic composition comprising a perovskite-type crystal structure represented by O 3 Where x, y, z are: (1) 0.42 ≦ x ≦ 0.45 0.46 ≦ y ≦ 0.49 0.08 ≦ z ≦ 0.150 x + y + z = 1, and a, b, and c are 0.05 for a = 1. ≦ b ≦ 0.30 0.20 ≦ c ≦ 0.50, wherein 3 to 15 atom% of Pb in the composition is replaced by at least one selected from Ba, Ca and Sr. .
本発明の磁器組成物の各金属元素の割合を上記の範囲
に設定したのは、ｘ値が0.42より小さいと電気機械結合
係数が小さく、0.45より大きくなると温度サイクル後の
共振周波数の変動（ドリフト）が大きくなる。また、ｚ
値が0.08より小さいと焼結性が悪く、0.15より大きいキ
ュリー点（Tc）が低くなる。The ratio of each metal element in the porcelain composition of the present invention is set in the above range. When the value x is smaller than 0.42, the electromechanical coupling coefficient is small, and when the value x is larger than 0.45, the resonance frequency fluctuation (drift) after temperature cycling. ) Increases. Also, z
If the value is smaller than 0.08, the sinterability is poor, and the Curie point (Tc) larger than 0.15 is low.
また、Nb、MgおよびMnの割合において、ａ＝１に対
し、ｂ値が0.30より大きいとQmが大きく低下する。ま
た、ｃ値が0.20より小さいと温度サイクル後のfaドリフ
トが大きくなる。なお、Mn量の上限値は、第３成分であ
るNb、Mg、Mnの全体の価数を平均４価にするためにはMn
量は0.5となることにより設定した。Further, in the ratio of Nb, Mg, and Mn, if a value of b is larger than 0.30 with respect to a = 1, Qm is greatly reduced. If the c value is smaller than 0.20, the fa drift after the temperature cycle increases. Note that the upper limit of the amount of Mn is Mn in order to make the total valence of Nb, Mg, and Mn as the third component an average of four.
The amount was set to be 0.5.
Nb、Mg、Mnの添加量の最適値は式（１）で、ａ＝１に
対して0.05≦ｂ≦0.25、0.25≦ｃ≦0.40である。The optimum values of the added amounts of Nb, Mg, and Mn are expressed by the formula (1), where a = 1 and 0.05 ≦ b ≦ 0.25 and 0.25 ≦ c ≦ 0.40.
また、本発明によれば、上記の圧電磁器組成物に対し
て、Ba、CaおよびSrの酸化物を添加することにより何ら
悪影響を及ぼすことなく誘電率εｒを高めることができ
る。Ba、CaおよびSrの酸化物はそれ自体、前述した式
（１）で表されるペロブスカイト型結晶構造においてＡ
サイトを形成する。本発明によれば、式（１）において
ＡサイトであるPbに対し３〜13原子％、特に８〜12原子
％の割合でPbの一部を置換する。この置換量が３原子％
未満では誘電率の向上効果が期待できず、13原子％を越
えると耐熱性の劣化という問題が生じる。Further, according to the present invention, the dielectric constant εr can be increased without any adverse effect by adding oxides of Ba, Ca and Sr to the piezoelectric ceramic composition. The oxides of Ba, Ca and Sr are themselves A in the perovskite type crystal structure represented by the above formula (1).
Form a site. According to the present invention, a part of Pb is substituted at a rate of 3 to 13 atomic%, particularly 8 to 12 atomic%, with respect to Pb which is an A site in the formula (1). This substitution amount is 3 atomic%
If it is less than 13%, the effect of improving the dielectric constant cannot be expected, and if it exceeds 13 atomic%, the problem of deterioration in heat resistance occurs.
本発明において磁器の製造に際しては、周知の方法が
採用でき、具体的には前述した組成を形成するPbO、TiO
2、ZrO2、Nb2O5、MgCO3、MnO2等の構成金属元素の各金
属酸化物を原料粉末としてそれらの割合が前述の範囲に
なるように秤量混合する。この時、用いる原料は酸化物
粉末や炭酸塩やしゅう酸塩等も使用できる。また、調合
に当たっては上記の各酸化物粉末を組合せて仮焼しPbTi
O3やPbZrO3等の複合酸化物粉末を調製し混合することも
当然可能である。In the production of porcelain in the present invention, well-known methods can be employed, and specifically, PbO, TiO
2 , metal oxides of constituent metal elements such as ZrO 2 , Nb 2 O 5 , MgCO 3 , and MnO 2 are used as raw material powders and weighed and mixed such that their proportions fall within the above-mentioned range. At this time, as a raw material to be used, oxide powder, carbonate, oxalate and the like can be used. In addition, the above oxide powders were combined and calcined to prepare PbTi.
Of course, it is also possible to prepare and mix a composite oxide powder such as O 3 or PbZrO 3 .
秤量混合した混合粉末はプレス成形、ドクターブレー
ド法等により所望の形状に成形した後に焼成する。The weighed mixed powder is formed into a desired shape by press molding, a doctor blade method or the like, and then fired.
焼成は、1200〜1340℃の酸化性雰囲気中で２〜６時間
行えばよい。The firing may be performed in an oxidizing atmosphere at 1200 to 1340 ° C. for 2 to 6 hours.
得られる焼結体は相対密度95％以上の高密度体である
ことが波形不良を抑制する上で望ましく、例えば通常の
焼成法により得られた焼結体を熱間静水圧焼成法により
1000〜1200℃、500〜2000気圧下の酸化性雰囲気中で焼
成することにより相対密度97％以上の焼結体を得ること
ができる。The obtained sintered body is desirably a high-density body having a relative density of 95% or more in order to suppress waveform defects. For example, a sintered body obtained by a normal firing method is subjected to a hot isostatic firing method.
By firing in an oxidizing atmosphere at 1000 to 1200 ° C. and 500 to 2000 atm, a sintered body having a relative density of 97% or more can be obtained.
以下、本発明を次の例で説明する。 Hereinafter, the present invention will be described with reference to the following examples.
（実施例） 出発原料として、純度99.5％以上、平均粒径が1.0〜
3.0μｍの市販のPbO、TiO2、ZrO2、Nb2O5、MgCO3、Mn
O2、BaCO3、CaCO3およびSrCO3の各粉末を用いて第１表
に示す割合で秤量し、ボールミルにて湿式混合後乾燥し
てこれを1000℃で仮焼した。(Example) As a starting material, the purity is 99.5% or more, and the average particle size is 1.0 to
3.0 μm commercially available PbO, TiO 2 , ZrO 2 , Nb 2 O 5 , MgCO 3 , Mn
Each powder of O 2 , BaCO 3 , CaCO 3 and SrCO 3 was weighed at the ratio shown in Table 1, wet-mixed in a ball mill, dried and calcined at 1000 ° C.
得られた仮焼物をボールミルにて24時間湿式粉砕した
後、有機系粘結剤を添加し、しかる後直径17mm、高さ1.
5mmの円柱状に加圧成形した。After the obtained calcined product was wet-pulverized for 24 hours by a ball mill, an organic binder was added, and then the diameter was 17 mm and the height was 1.
It was press-formed into a 5 mm cylindrical shape.
得られた成形体を酸化性雰囲気にて1260〜1340℃で６
時間焼成した。The obtained molded body is heated at 1260 to 1340 ° C in an oxidizing atmosphere for 6 hours.
Fired for hours.
焼結体を直径15mm、高さ1mmに研磨加工しその両端面
に銀ペーストを焼き付けた。出来上がった素子を80℃の
絶縁油中に浸漬し、両端面に5KV/mmの直流電圧を印加し
て分極処理した。The sintered body was polished to a diameter of 15 mm and a height of 1 mm, and silver paste was baked on both end surfaces. The completed device was immersed in insulating oil at 80 ° C., and a polarization treatment was performed by applying a DC voltage of 5 KV / mm to both end surfaces.
分極後、24時間経過した素子の特性をインピーアナラ
イザーにより電気機械結合係数（Kp）、機械的品質係数
（Qm）、比誘電率（εｒ）ならびにfaドリフトを測定し
た。24 hours after the polarization, the characteristics of the device were measured with an impedance analyzer for electromechanical coupling coefficient (Kp), mechanical quality coefficient (Qm), relative permittivity (εr) and fa drift.
結果は第１表に示した。 The results are shown in Table 1.
第１表によれば、各元素の組成が本発明の範囲にある
試料はいずれも優れた特性を示し、Kpが40以上、Qmが15
00以上、εｒが1000以上、faドリフトが±0.3以内が達
成され、特にPbの一部をBa、Ca、Srで置換することによ
りεｒを高めることができた。 According to Table 1, all the samples in which the composition of each element is within the range of the present invention show excellent characteristics, and have a Kp of 40 or more and a Qm of 15 or more.
At least 00, εr of 1000 or more, and fa drift within ± 0.3 were achieved. In particular, εr could be increased by substituting a part of Pb with Ba, Ca, and Sr.
これに対して磁器組成物の各添加量が範囲を逸脱する
試料は、いずれも特性上不十分であり、本発明の目的を
達成することができなかった。On the other hand, all of the samples in which the amount of the porcelain composition added deviated from the range were insufficient in characteristics and could not achieve the object of the present invention.
（発明の効果） 以上詳述した通り、本発明の圧電磁器組成物はPZTに
対し（Nb−Mg−Mn）系酸化物を添加することにより機械
的品質係数を大幅に向上でき、さらにPbの一部をBa、Ca
あるいはSrで置換することにより比誘電率を向上するこ
とできる。これによりフィルタ用として特に中間周波数
帯域の低損失型として高選択性を付与することができ
る。(Effect of the Invention) As described in detail above, the piezoelectric ceramic composition of the present invention can significantly improve the mechanical quality factor by adding an (Nb-Mg-Mn) -based oxide to PZT, Partly Ba, Ca
Alternatively, the relative permittivity can be improved by substituting with Sr. Thereby, high selectivity can be imparted to the filter, particularly as a low-loss type in the intermediate frequency band.
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.6，ＤＢ名) C04B 35/49──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 6 , DB name) C04B 35/49
Claims (2)
組成物であって、 式中、x,y,zは 0.42≦ｘ≦0.45 0.46≦ｙ≦0.49 0.08≦ｚ≦0.150 ｘ＋ｙ＋ｚ＝１ であり、a,b,cは、ａ＝１に対し 0.05≦ｂ≦0.30 0.20≦ｃ≦0.50 で表される圧電磁器組成物。1. A piezoelectric ceramic composition represented by the following formulas Pb {Zr x Ti y (Nb a Mg b Mn c) 2} perovskite-type crystal structure represented by O 3, wherein, x, y, z is 0.42 ≦ x ≦ 0.45 0.46 ≦ y ≦ 0.49 0.08 ≦ z ≦ 0.150 x + y + z = 1, and a, b, and c are the piezoelectric expressed by 0.05 ≦ b ≦ 0.30 0.20 ≦ c ≦ 0.50 for a = 1. Porcelain composition.
およびSrから選ばれる少なくとも１種で置換した請求項
１記載の圧電磁器組成物。2. The composition according to claim 1, wherein 3-15 atomic% of Pb is Ba, Ca
The piezoelectric ceramic composition according to claim 1, wherein the piezoelectric ceramic composition is substituted with at least one selected from Sr and Sr.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2319182A JP2866986B2 (en) | 1990-11-22 | 1990-11-22 | Piezoelectric ceramic composition |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2319182A JP2866986B2 (en) | 1990-11-22 | 1990-11-22 | Piezoelectric ceramic composition |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04188882A JPH04188882A (en) | 1992-07-07 |
| JP2866986B2 true JP2866986B2 (en) | 1999-03-08 |
Family
ID=18107334
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2319182A Expired - Fee Related JP2866986B2 (en) | 1990-11-22 | 1990-11-22 | Piezoelectric ceramic composition |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2866986B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3562402B2 (en) * | 1999-09-29 | 2004-09-08 | 株式会社村田製作所 | Piezoelectric ceramic material and surface wave device using the same |
| JP3783534B2 (en) * | 2000-08-18 | 2006-06-07 | 株式会社村田製作所 | Piezoelectric ceramic sintered body and piezoelectric ceramic element |
| KR100544091B1 (en) * | 2002-12-05 | 2006-01-25 | 주식회사 스마텍 | Piezoelectric Ceramic Composition |
| JP5170905B2 (en) * | 2009-10-13 | 2013-03-27 | 日本特殊陶業株式会社 | Non-resonant knock sensor |
-
1990
- 1990-11-22 JP JP2319182A patent/JP2866986B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04188882A (en) | 1992-07-07 |
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