JPH0319714B2 - - Google Patents

Info

Publication number
JPH0319714B2
JPH0319714B2 JP23700686A JP23700686A JPH0319714B2 JP H0319714 B2 JPH0319714 B2 JP H0319714B2 JP 23700686 A JP23700686 A JP 23700686A JP 23700686 A JP23700686 A JP 23700686A JP H0319714 B2 JPH0319714 B2 JP H0319714B2
Authority
JP
Japan
Prior art keywords
powder
piezoelectric
sintering
sheets
sintered
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 - Lifetime
Application number
JP23700686A
Other languages
Japanese (ja)
Other versions
JPS6392069A (en
Inventor
Kogaku Ochiai
Noboru Miura
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JGC Corp
Original Assignee
JGC Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by JGC Corp filed Critical JGC Corp
Priority to JP61237006A priority Critical patent/JPS6392069A/en
Publication of JPS6392069A publication Critical patent/JPS6392069A/en
Publication of JPH0319714B2 publication Critical patent/JPH0319714B2/ja
Granted legal-status Critical Current

Links

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、鉛、ビスマス、錫などの揮発性成分
を含んだ圧電体シート焼結体の製造方法に関する
もである。特に厚さが50μm〜0.5mmの焼結体の焼
結に際し、揮発分の揮発を抑え、かつ、そり、う
ねりの小さい薄板を効率良く、かつ安定に製造で
きる方法を提供するものである。
DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a piezoelectric sheet sintered body containing volatile components such as lead, bismuth, and tin. In particular, the present invention provides a method for efficiently and stably manufacturing thin plates with small warpage and waviness while suppressing the volatilization of volatile components when sintering a sintered body having a thickness of 50 μm to 0.5 mm.

〔従来の技術及びその問題点〕[Conventional technology and its problems]

圧電体薄板セラミツクスは圧電ブザー、スピー
カー、アクチユエーターなどの応用分野は多岐に
恒り、生産規模も増大の一途にある。
Piezoelectric thin plate ceramics are being applied in a wide variety of fields, such as piezoelectric buzzers, speakers, and actuators, and the scale of production is continuing to increase.

このため、効率的な製造方法が望まれている。
通常、圧電体薄板セラミツクスの製造は、焼結体
ブロツクを切断、研摩加工する方法と、圧電セラ
ミツク原料粉を有機結合剤、有機溶剤と混合し、
スラリーとなし、これをドクタープレード法など
の方法によりグリーンシートを作り、所望の形に
打ち抜き焼結する方法がある。前者の方法は切
断、研摩加工に工数が掛り大量生産には不利であ
る。一方、後者は焼成時の収縮のため変形、亀
裂、反り、うねりが生ずることが多い。また薄板
製造の場合は、ブロツク状の場合に比し体積当り
の外表面積が大きいため鉛、ビスマス、錫などの
揮発成分を含むものではこれら揮発分が焼結時に
揮発し焼結体に不均一を生ずる欠点があつた。
Therefore, an efficient manufacturing method is desired.
Normally, piezoelectric thin plate ceramics are manufactured by cutting and polishing a sintered block, mixing piezoelectric ceramic raw material powder with an organic binder and an organic solvent,
There is a method in which a slurry is made, a green sheet is made from this using a method such as a doctor blade method, and the green sheet is punched into a desired shape and sintered. The former method requires many man-hours for cutting and polishing, and is disadvantageous for mass production. On the other hand, the latter often suffers from deformation, cracking, warping, and waviness due to shrinkage during firing. In addition, in the case of manufacturing thin plates, the outer surface area per volume is larger than in the case of blocks, so if the material contains volatile components such as lead, bismuth, and tin, these volatile components will volatilize during sintering, resulting in unevenness in the sintered body. There was a defect that caused this.

これまでに、グリーンシートを焼結する際に、
グリーンシート面に散布または塗布する粉体とし
て、酸化アルミニウム、酸化マグネシウム、酸化
ジルコニウムなどの高融点酸化物を用いる方法
(特公昭60−8990号公報、特開昭56−14476号公
報)、純度95%以上、粒径2〜7μmで分級された
酸化ジルコニウムを用いる方法(特開昭57−
60877号公報)、シート素材と同じ組成の焼結され
た焼結材粉末を用いる方法(特開昭57−190377号
公報)及び1000〜1400℃で熱処理した10〜50μm
の粒子を80重量%以上含むジルコニア粉末を用い
る方法(特開昭61−31353号公報)などが提案さ
れている。
Until now, when sintering green sheets,
Method using high melting point oxides such as aluminum oxide, magnesium oxide, zirconium oxide, etc. as powder to be sprinkled or coated on the green sheet surface (Japanese Patent Publication No. 60-8990, Japanese Patent Application Laid-Open No. 14476-1983), purity 95 % or more, and a method using zirconium oxide classified with a particle size of 2 to 7 μm (Japanese Patent Application Laid-Open No. 1987-
60877), a method using sintered material powder having the same composition as the sheet material (Japanese Patent Application Laid-open No. 190377/1983), and a method of 10 to 50 μm heat-treated at 1000 to 1400°C.
A method using zirconia powder containing 80% by weight or more of particles has been proposed (Japanese Unexamined Patent Publication No. 31353/1983).

上記のうち、ジルコニア、アルミナ、マグネシ
アなどの粉末を用いるケースではこれら粉末が焼
結体に喰い込み凹凸を生じ、またジルコニア、ア
ルミナは特に酸化鉛と反応しやすく酸化鉛の外部
への拡散を助長するため、焼結体に不均一を生じ
やすいという欠点がある。
Among the above, in cases where powders such as zirconia, alumina, and magnesia are used, these powders dig into the sintered body and cause unevenness, and zirconia and alumina are particularly prone to react with lead oxide, promoting the diffusion of lead oxide to the outside. Therefore, there is a drawback that non-uniformity tends to occur in the sintered body.

他方、シート素材と同じ組成の焼結された焼結
粉末では上記のような問題はないが、1度高温で
焼結されたものを粉砕することは極めて困難な作
業であり、粉砕工程で不純物などの混入の危検性
が多い。さらに焼結体を粉砕できたとしてもこの
粉体は一度、焼結温度に加熱されており、もはや
収縮しない。このためグリーンシート間にある粉
末に角部があれば焼結体表面に凹凸部が出来易
い。したがつてグリーンシートの間に散布粉末の
大きさに限定が生ずる。特開昭57−190377号公報
ではこの粒径を1〜5μmとしている。しかし、
1〜5μmの粉末を効率良く作ることは極めて困
難であると考えられる。
On the other hand, sintered powder with the same composition as the sheet material does not have the above problems, but it is an extremely difficult task to crush something that has been sintered at a high temperature, and impurities are generated during the crushing process. There is a high risk of contamination. Furthermore, even if the sintered body can be crushed, this powder has already been heated to the sintering temperature and will no longer shrink. Therefore, if the powder between the green sheets has corners, uneven portions are likely to be formed on the surface of the sintered body. Therefore, there is a limit to the size of the powder to be spread between the green sheets. In JP-A-57-190377, the particle size is set to 1 to 5 μm. but,
It is considered extremely difficult to efficiently produce powder with a size of 1 to 5 μm.

〔発明の目的〕[Purpose of the invention]

本発明は、以上の従来技術における問題を解決
して均一な圧電体薄板セラミツクスを効率良く、
安定に製造する方法を提供することを目的とす
る。
The present invention solves the problems in the prior art described above and efficiently produces uniform piezoelectric thin plate ceramics.
The purpose is to provide a stable manufacturing method.

〔発明の構成〕[Structure of the invention]

本発明は、焼結することにより圧電特性を示す
圧電体原料粉末より製造したグリーンシートと重
ねて焼結するに際し、該グリーンシート間にグリ
ーンシートを製造する際に使用した圧電体原料粉
末と同一組成の600〜900℃で仮焼された粒度1〜
50μmの粉末を散布もしくは塗布して重ね焼きす
る方法である。
In the present invention, when stacking and sintering a green sheet produced from a piezoelectric material powder that exhibits piezoelectric properties by sintering, the piezoelectric material powder used in producing the green sheet between the green sheets is the same. Particle size 1~ calcined at 600~900℃ of composition
This is a method in which 50 μm powder is sprinkled or coated and layered.

本発明者らは、前記諸問題を解決すべく鋭意研
究した結果、グリーンシートの製造に用いたのと
同じ圧電体原料粉末を600〜900℃で仮焼し、これ
を1〜50μmの範囲内の大きさに粉砕もしくは微
粉砕した粉末をグリーンシートの間に散布もしく
は塗布した後グリーンシートを重ね焼きすること
により効率良く、かつ安定して焼結薄板を製造し
うることを見いだし本発明をなすに至つた。
As a result of intensive research to solve the above-mentioned problems, the present inventors calcined the same piezoelectric raw material powder used for manufacturing green sheets at 600 to 900°C, We have discovered that it is possible to efficiently and stably produce a sintered thin plate by scattering or coating powder that has been crushed or finely pulverized to a size between green sheets, and then baking the green sheets in layers, and have thus accomplished the present invention. It came to this.

以下、本発明を詳しく説明する。 The present invention will be explained in detail below.

本発明に用いられる圧電体セラミツクス素材は
鉛、ビスマス、錫などの揮発性成分を含むペロブ
スカイト型、タングステンブロンズ型結晶化合物
からなるものであれば単成分、多成分いずれでも
良い。
The piezoelectric ceramic material used in the present invention may be either single-component or multi-component as long as it is made of perovskite-type or tungsten bronze-type crystalline compounds containing volatile components such as lead, bismuth, and tin.

上記素材を構成する原料粉をボールミルなどに
より混合し600〜900℃で仮焼する。この仮焼粉の
一部を取り、粉砕機により1〜50μmに粉砕する
か、あるいは湿式ボールミルなどにより微粉砕
し、スプレー乾燥により1〜50μmの粉末を得
る。
The raw material powders constituting the above material are mixed using a ball mill or the like and calcined at 600 to 900°C. A portion of this calcined powder is taken and pulverized to a size of 1 to 50 .mu.m using a pulverizer, or finely pulverized using a wet ball mill or the like, and then spray-dried to obtain a powder of 1 to 50 .mu.m.

粒径が1μm以下となると粉末の流動性が悪く
なり取り扱いが困難となり、また50μm以上では
焼結体薄板の表面性状が悪くなる。
When the particle size is less than 1 μm, the fluidity of the powder deteriorates and it becomes difficult to handle, and when it is more than 50 μm, the surface quality of the sintered thin plate deteriorates.

粉砕方法または造粒方法については何ら限定す
るものはない。
There are no limitations on the pulverization method or granulation method.

他方、仮焼粉の大部分は有機結合剤、可塑剤、
揮発性有機溶剤と混合されボールミル、チユーブ
ミル、振動ミルなどにより混合され、ドクターブ
レード法などによる製造に適した粘度に調整しつ
つ脱泡される。ここに用いられる有機結合剤、可
塑剤等およびそれらの混合率は通常用いられてい
る比率で特に問題はない。また、ドクターブレー
ド用スラリーの調製は有機溶剤法に限定するもの
でなく、水溶液法でも良い。
On the other hand, most of the calcined powder contains organic binders, plasticizers,
The mixture is mixed with a volatile organic solvent using a ball mill, tube mill, vibration mill, etc., and defoamed while adjusting the viscosity to be suitable for manufacturing using a doctor blade method. The organic binder, plasticizer, etc. used here and the mixing ratio thereof are the commonly used ratios and there is no particular problem. Further, the preparation of the slurry for doctor blades is not limited to the organic solvent method, but may also be an aqueous solution method.

上記スラリーをドクターブレード法などにより
グリーンシートにする。
The above slurry is made into a green sheet by a doctor blade method or the like.

このグリーンシートを所定の寸法に切断後、先
に調整した1〜50μmの仮焼粉をグリーンシート
表面に散布または塗布し、これを重ねる。重ねる
枚数はグリーンシートの厚みによるが、50μmで
10〜300枚100μmで10〜200枚、0.5mmで5〜40枚
程度が好ましい。
After cutting this green sheet into a predetermined size, the previously adjusted calcined powder of 1 to 50 μm is sprinkled or coated on the surface of the green sheet, and the green sheet is overlapped. The number of stacked sheets depends on the thickness of the green sheet, but 50 μm
10 to 300 sheets, preferably 10 to 200 sheets at 100 μm, and 5 to 40 sheets at 0.5 mm.

前記重ねる枚数の下限値以下の枚数の場合重ね
焼結による工業的効果が小さく、また重ねた際の
全体の厚みが小さい場合には外表面積が大きくな
り過ぎて揮発成分の揮発が問題となつてくるため
雰囲気制御に特別な工夫が必要となつてくる。
If the number of stacked sheets is below the lower limit value, the industrial effect of stacked sintering will be small, and if the overall thickness when stacked is small, the outer surface area will become too large and volatilization of volatile components will become a problem. Therefore, special measures are needed to control the atmosphere.

他方、上記の重ねる枚数の上限以上となる場
合、焼結時に下部のシート同志が融着する傾向が
みられるので好ましくない。
On the other hand, if the number of stacked sheets exceeds the above upper limit, the lower sheets tend to fuse together during sintering, which is not preferable.

粉の散布または塗布方法については特に限定は
ない。例えばグリーンシートを並べておき、フル
イを通し、グリーンシート表面に散布する方法、
粉を水に懸濁させておきグリーンシートに塗布す
る方法などがある。
There are no particular limitations on the powder scattering or application method. For example, a method of arranging green sheets, passing them through a sieve, and scattering them on the surface of the green sheets,
There are methods such as suspending the powder in water and applying it to the green sheet.

以上のように粉体を散布または塗布されたグリ
ーンシートを重ね電気炉内で500℃程度の温度で
十分脱脂し室温まで徐冷する。ついでこのもの
を、積み重ねた状態でさや詰し、密閉し、焼結す
る。焼結温度は用いる圧電体素材に適した温度で
行われるが、通常は1000℃〜1350℃の範囲内の温
度が用いられる。
The green sheets sprinkled with or coated with powder as described above are stacked and thoroughly degreased in an electric furnace at a temperature of about 500°C, and then slowly cooled to room temperature. This material is then stacked in a pod, sealed, and sintered. Sintering is carried out at a temperature suitable for the piezoelectric material used, but usually a temperature within the range of 1000°C to 1350°C is used.

本発明によれば反り、うねりが少なく、反り戻
し焼結はまつたく不要で、均質で良好な圧電特性
を示す薄板焼結体が得られる。
According to the present invention, it is possible to obtain a thin plate sintered body with little warpage and waviness, no need for warp-back sintering, and exhibiting homogeneous and good piezoelectric properties.

以下、本発明について実施例により説明する。 The present invention will be explained below using examples.

実施例 1 Pb(Zr0.535 Ti0.465)O3の組成比になるよう
配合された原料粉末を湿式ボールミル粉砕し、
850℃で仮焼した。この1部を取り、1〜50μm
にメノウ乳鉢で粉砕、融着防止用粉末を得た。次
に、残りの仮焼粉に結合剤3重量%、可塑剤2重
量%、分散剤0.2重量%、湿潤剤2重量%を加え、
さらに溶剤としてエタノール、MEK、イソプロ
パノール、ブタノールを合せて40重量%を加え、
ボールミルにて24時間混合した。この混合物を真
空脱泡機に入れ粘度が30000cpになるよう粘度調
整しつつ脱泡し、シート用スラリーを得た。この
スラリーをドクターブレード法により乾燥膜厚
0.1mmの生シートを得た。これを30mmφの円板に
打抜き、100メツシユの振動機付フルイ下をコン
ベヤーで流し、円板上に前記粉体を散布した。こ
の円板を150枚重ね電気炉内で500℃で脱脂したの
ち、アルミナ製匣鉢に密閉し、1200℃で3時間焼
結した。
Example 1 Raw material powder blended to have a composition ratio of Pb(Zr0.535 Ti0.465)O 3 was ground in a wet ball mill,
Calcined at 850℃. Take one part of this and make it 1~50μm.
The mixture was ground in an agate mortar to obtain a powder for preventing adhesion. Next, 3% by weight of binder, 2% by weight of plasticizer, 0.2% by weight of dispersant, and 2% by weight of wetting agent were added to the remaining calcined powder.
Furthermore, a total of 40% by weight of ethanol, MEK, isopropanol, and butanol was added as a solvent.
The mixture was mixed in a ball mill for 24 hours. This mixture was placed in a vacuum defoaming machine and defoamed while adjusting the viscosity to 30,000 cp to obtain a slurry for sheets. This slurry is dried to a film thickness using the doctor blade method.
A green sheet of 0.1 mm was obtained. This was punched into a disk of 30 mmφ and passed through a 100-mesh vibrating sieve using a conveyor to scatter the powder onto the disk. After stacking 150 of these disks and degreasing them at 500°C in an electric furnace, they were sealed in an alumina sagger pot and sintered at 1200°C for 3 hours.

得られた薄板焼結体は反りうねりが少なく、電
極印刷時の割れは皆無であつた。
The obtained thin plate sintered body had little warpage and no cracks during electrode printing.

実施例 2 実施例1で用いたスラリーから乾燥膜厚0.6mm
の生シートを得た。これを40mm×70mmに打ち抜
き、実施例1と同様に生シート上に粉を散布し
た。この矩形板を30枚重ね、実施例1の方法で脱
脂、焼結した。得られた薄板焼結体は反り、うね
りが少なく電極印刷時の割れは皆無であつた。
Example 2 Dry film thickness of 0.6 mm from the slurry used in Example 1
I got raw sheets. This was punched out into a size of 40 mm x 70 mm, and powder was sprinkled on the raw sheet in the same manner as in Example 1. Thirty of these rectangular plates were stacked, degreased and sintered in the same manner as in Example 1. The obtained thin plate sintered body had little warpage or waviness, and there were no cracks during electrode printing.

実施例 3 実施例1で用いたと同じ仮焼粉を用い、その1
部を取り、1.5wt%の結合剤、0.2wt%の分散材、
少量の消泡材と水を加え16時間ボールミルしたの
ち、スプレードライヤーにて1〜50μmの粉体を
得た。次に、実施例1、2で得た生シート上に上
記粉体を散布し0.1mmの厚さのものについては200
枚、0.6mmの厚さのものについては40枚重ね、実
施例1、2と同様に脱脂、焼結した。
Example 3 Using the same calcined powder as used in Example 1,
1.5wt% binder, 0.2wt% dispersant,
After adding a small amount of antifoaming agent and water and ball milling for 16 hours, a powder of 1 to 50 μm was obtained using a spray dryer. Next, the above powder was sprinkled on the raw sheets obtained in Examples 1 and 2, and 200
40 sheets with a thickness of 0.6 mm were stacked, degreased and sintered in the same manner as in Examples 1 and 2.

得られた薄板は実施例1、2と同様、良好であ
つた。
The obtained thin plate was good as in Examples 1 and 2.

〔発明の効果〕〔Effect of the invention〕

600〜900℃で仮焼した粉体を用いることにより 600〜900℃では粉体同志の固着が弱く容易に
1〜5μmに粉砕できるため、粉砕コストも安
く、不純物も混入されにくい。
By using powder calcined at 600 to 900°C, the adhesion of the powders to each other is weak at 600 to 900°C, and it can be easily ground to 1 to 5 μm, so the grinding cost is low and impurities are less likely to be mixed in.

微粉砕も容易であり、スプレードライヤーな
どにより1〜50μmの造粒粉を得やすい。
It is easy to pulverize, and it is easy to obtain granulated powder of 1 to 50 μm using a spray dryer or the like.

焼結時、粉自体が部分焼結し、粒径が小さく
なるため散布または塗布する粒径の範囲を広く
取つても反り、うねり等に対してもまつたく問
題ない。
During sintering, the powder itself is partially sintered and the particle size becomes smaller, so there is no problem with warping, waviness, etc. even if the particle size range for scattering or coating is wide.

以上、散布または塗布する粉末の調製が極め
て容易である。
As described above, it is extremely easy to prepare a powder to be sprayed or applied.

など実用値価値が大きい。It has great practical value.

Claims (1)

【特許請求の範囲】[Claims] 1 焼結することにより圧電特性を示す圧電体原
料粉末より製造したグリーンシートを重ねて焼結
するに際し、該グリーンシート間にグリーンシー
トを製造する際に使用する圧電体原料粉末と同一
組成の600〜900℃で仮焼された粒径1〜50μmの
粉末を散布もしくは塗布して重ね焼きすることを
特徴とする圧電セラミツク薄板焼結体の製造方
法。
1. When stacking and sintering green sheets manufactured from piezoelectric raw material powder that exhibits piezoelectric properties by sintering, a 600% carbon fiber having the same composition as the piezoelectric raw material powder used in manufacturing the green sheet is placed between the green sheets. A method for producing a piezoelectric ceramic thin plate sintered body, which comprises scattering or coating powder with a particle size of 1 to 50 μm calcined at ~900°C and then over-firing.
JP61237006A 1986-10-07 1986-10-07 Manufacture of sintered thin plate of piezoelectric ceramic Granted JPS6392069A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP61237006A JPS6392069A (en) 1986-10-07 1986-10-07 Manufacture of sintered thin plate of piezoelectric ceramic

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP61237006A JPS6392069A (en) 1986-10-07 1986-10-07 Manufacture of sintered thin plate of piezoelectric ceramic

Publications (2)

Publication Number Publication Date
JPS6392069A JPS6392069A (en) 1988-04-22
JPH0319714B2 true JPH0319714B2 (en) 1991-03-15

Family

ID=17008989

Family Applications (1)

Application Number Title Priority Date Filing Date
JP61237006A Granted JPS6392069A (en) 1986-10-07 1986-10-07 Manufacture of sintered thin plate of piezoelectric ceramic

Country Status (1)

Country Link
JP (1) JPS6392069A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6715192B2 (en) * 1998-12-28 2004-04-06 Ngk Insulators, Ltd. Method for manufacturing a piezoelectric/electrostrictive device

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61208880A (en) * 1985-03-14 1986-09-17 Nec Corp Manufacture of electrostrictive effect element

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61208880A (en) * 1985-03-14 1986-09-17 Nec Corp Manufacture of electrostrictive effect element

Also Published As

Publication number Publication date
JPS6392069A (en) 1988-04-22

Similar Documents

Publication Publication Date Title
US4735666A (en) Method of producing ceramics
US6277254B1 (en) Ceramic compositions, physical vapor deposition targets and methods of forming ceramic compositions
EP0169636B1 (en) Low-temperature-fired dielectric ceramic composition with a flat temperature characteristic
JP2013507526A (en) Tin oxide ceramic sputtering target and method for producing the same
US7381671B2 (en) Ferroelectric ceramic composition and applied ferroelectric element including same
CN1206700A (en) Sintered piezoelectric ceramics, piezoelectric ceramic device, and preparation process thereof
JP4582835B2 (en) Method for manufacturing piezoelectric member for actuator
JPH0319714B2 (en)
RU2801090C1 (en) Modified material for electrostrictor
JP3042899B2 (en) Mixture of fine-grained barium titanate and method for producing the same
JP3914635B2 (en) Manufacturing method of ceramic electronic component
JP3018683B2 (en) Method for producing lead-containing ceramics
JP3036094B2 (en) Method for preparing clay for extrusion molding
JPH0579941B2 (en)
JPH0524916A (en) Piezoelectric porcelain material
KR20110115718A (en) Method for manufacturing ferroelectric ceramics and ferroelectric ceramics manufactured by the method
JPH02197181A (en) Ferroelectric porcelain body
JPH04306889A (en) Manufacture of electrostrictive element
Umakantham et al. Ferroelectric properties and microstructure of doped PbTiO3 ceramics
JPS63136677A (en) Manufacture of piezoelectric ceramics thin plate
JPH06116024A (en) Production of bismuth laminar compound
JPH04325464A (en) Method for burning piezoelectric ceramics
JPS608990B2 (en) Method for manufacturing piezoelectric sintered sheet
JPH02197182A (en) Ferroelectric porcelain body
JPH0848572A (en) Manufacture of piezoelectric ceramic element containing lead compound