JPH0426546A - Production of high strength zirconia ceramics having high acid resistance - Google Patents
Production of high strength zirconia ceramics having high acid resistanceInfo
- Publication number
- JPH0426546A JPH0426546A JP2129846A JP12984690A JPH0426546A JP H0426546 A JPH0426546 A JP H0426546A JP 2129846 A JP2129846 A JP 2129846A JP 12984690 A JP12984690 A JP 12984690A JP H0426546 A JPH0426546 A JP H0426546A
- Authority
- JP
- Japan
- Prior art keywords
- phase
- acid resistance
- zirconia
- powder
- zirconia ceramics
- 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
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 title claims abstract description 52
- 239000002253 acid Substances 0.000 title claims abstract description 17
- 239000000919 ceramic Substances 0.000 title claims description 16
- 238000004519 manufacturing process Methods 0.000 title claims description 8
- 238000000137 annealing Methods 0.000 claims abstract description 16
- RKTYLMNFRDHKIL-UHFFFAOYSA-N copper;5,10,15,20-tetraphenylporphyrin-22,24-diide Chemical compound [Cu+2].C1=CC(C(=C2C=CC([N-]2)=C(C=2C=CC=CC=2)C=2C=CC(N=2)=C(C=2C=CC=CC=2)C2=CC=C3[N-]2)C=2C=CC=CC=2)=NC1=C3C1=CC=CC=C1 RKTYLMNFRDHKIL-UHFFFAOYSA-N 0.000 claims abstract description 10
- 238000005498 polishing Methods 0.000 claims description 9
- 238000010304 firing Methods 0.000 claims description 5
- 239000000843 powder Substances 0.000 abstract description 12
- 230000003746 surface roughness Effects 0.000 abstract description 6
- 239000003381 stabilizer Substances 0.000 abstract description 5
- 239000002994 raw material Substances 0.000 abstract description 4
- 238000005245 sintering Methods 0.000 abstract description 3
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract description 2
- 229910052593 corundum Inorganic materials 0.000 abstract description 2
- 229910001845 yogo sapphire Inorganic materials 0.000 abstract description 2
- 238000001035 drying Methods 0.000 abstract 1
- 238000000227 grinding Methods 0.000 abstract 1
- 238000002156 mixing Methods 0.000 abstract 1
- 239000000203 mixture Substances 0.000 abstract 1
- 239000013078 crystal Substances 0.000 description 11
- 230000007704 transition Effects 0.000 description 10
- 238000000034 method Methods 0.000 description 6
- 238000010438 heat treatment Methods 0.000 description 3
- 238000002441 X-ray diffraction Methods 0.000 description 2
- 238000005452 bending Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 229910003460 diamond Inorganic materials 0.000 description 2
- 239000010432 diamond Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910002077 partially stabilized zirconia Inorganic materials 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 238000010998 test method Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 235000009849 Cucumis sativus Nutrition 0.000 description 1
- 240000008067 Cucumis sativus Species 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 235000019402 calcium peroxide Nutrition 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000013001 point bending Methods 0.000 description 1
- 230000004580 weight loss Effects 0.000 description 1
- 238000001238 wet grinding Methods 0.000 description 1
Landscapes
- Compositions Of Oxide Ceramics (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は高耐酸性の高強度ジルコニアセラミックスの製
造方法に関する。DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for manufacturing highly acid-resistant and high-strength zirconia ceramics.
（従来技術）
安定化剤としてＹ２Ｏ１を含有するＺｒ０ｔ粉末の焼結
体テするジルコニアセラミックスは部分安定化ジルコニ
アセラミックス（ＰＳＺ）と称され、高強度のジルコニ
アセラミックスとして機械構造材料としての用途開発が
なされている。(Prior art) Zirconia ceramics made of a sintered body of Zr0t powder containing Y2O1 as a stabilizer are called partially stabilized zirconia ceramics (PSZ), and have been developed for use as mechanical structural materials as high-strength zirconia ceramics. ing.
しかしながら、かかるジルコニアセラミックスの結晶構
造は準安定相であって経時変化を生じやすく、２００〜
４０Ｇ’ Ｃという比較的低い加熱により正方晶から単
斜晶へ相移転し、この相移転に伴う体積変化により強度
が経時的に劣化して熱安定性にかける。このため、かか
る相移転のし難いジルコニアセラミ・２クスの製造方法
が特開昭６１−７７６６５号公報、特開昭６３−６４９
６１号公報、特開昭６３−１５６０６ｆ１号公報等に示
されている。However, the crystal structure of such zirconia ceramics is a metastable phase and easily changes over time.
Heating at a relatively low temperature of 40 G'C causes a phase transition from tetragonal to monoclinic, and due to the volume change accompanying this phase transition, the strength deteriorates over time and thermal stability is affected. For this reason, methods for manufacturing zirconia ceramic 2x, which are difficult to undergo phase transfer, are disclosed in JP-A-61-77665 and JP-A-63-649.
This is disclosed in Japanese Patent Application Laid-Open No. 63-15606f1, etc.
（発明が解決しようとする課題）
ところで、一般にジルコニアセラミ、クスを素材とする
構造部品においては、焼結体に研磨加工を施して目的と
する形状に形成されるものであるが、単斜晶に相移転し
難いジルコニアセラミックス、すなわち結晶相のほとん
どが正方晶からなるジルコニアセラミックスを研磨加工
すると、単斜晶は発生しないものの斜方面体晶相（Ｒ相
）が焼結体の表面に発生する。かかるＲ相の発生により
機械的強度が向上することが知られている。しかしなが
ら、耐酸性および熱安定性に対する影響については何等
知られていない。(Problems to be Solved by the Invention) Generally speaking, structural parts made of zirconia ceramic or glass are formed into a desired shape by polishing a sintered body. When polishing zirconia ceramics that are difficult to undergo phase transition, that is, zirconia ceramics whose crystalline phase is mostly tetragonal, a monoclinic crystal phase does not occur, but an orthorhombahedral crystal phase (R phase) occurs on the surface of the sintered body. . It is known that mechanical strength is improved by the generation of such an R phase. However, nothing is known about the effects on acid resistance and thermal stability.
本発明者はジルコニア焼結体に研磨加工を施すと、焼結
体の表面相が正方晶相（Ｔ相）から斜方面体晶相に変態
することにより、耐酸性および熱安定性が著しく低下す
ることを見いだした。The present inventor discovered that when a zirconia sintered body is polished, the surface phase of the sintered body transforms from a tetragonal phase (T phase) to a rhombohedral phase, resulting in a significant decrease in acid resistance and thermal stability. I found something to do.
従って、本発明の目的は高耐酸性の高強度ジルコニアセ
ラミックスを提供することにある。Therefore, an object of the present invention is to provide a highly acid-resistant, high-strength zirconia ceramic.
＜ｍ題を解決するための手段）
本発明は高耐酸性の高強度ジルコニアセラミックスの製
造方法に関し、正方晶ジルコニア相が９９％以上で構成
されるジルコニア焼結体からなるジルコニアセラミック
スの製造方法であり、焼結体を研磨加工した後ｓｏｏ’
ｃ以上でかつ焼成温度以下の温度でアニール処理を施
すことを特徴とするものである。<Means for Solving Problem M) The present invention relates to a method for producing a highly acid-resistant, high-strength zirconia ceramic, and a method for producing a zirconia ceramic made of a zirconia sintered body composed of 99% or more of a tetragonal zirconia phase. Yes, after polishing the sintered body
This method is characterized in that the annealing treatment is performed at a temperature higher than c and lower than the firing temperature.
（発明の作用・効果）
本発明に係る製造方法によれば、研磨加工後にアニール
処理が施されて歪みが解消されるため、耐酸性および耐
熱性が向上するが、特に特定範囲の温度でアニール処理
を施して結晶構造中の正方晶の割合が９９％以上となっ
ているため、耐酸性および耐熱性は著しく高い。(Operations and Effects of the Invention) According to the manufacturing method according to the present invention, annealing treatment is performed after polishing to eliminate distortion, so acid resistance and heat resistance are improved. Since the treatment has made the proportion of tetragonal crystals in the crystal structure to be 99% or more, the acid resistance and heat resistance are extremely high.
なお、ジルコニアの結晶相が正方晶９９１以上としたの
は、研磨加工後にできる転移相を斜方面体晶相とするた
めである。正方晶が９９％以下になると、転移相が単斜
晶相（Ｍ相）になりやすい。この場合結晶相の平均粒子
径が０．１〜０２μである場合には単斜晶相への移転は
起こり難く、斜方面体晶相に移転する。The reason why the crystal phase of zirconia is set to be 991 or more tetragonal is to make the transition phase formed after polishing a rhombohedral crystal phase. When the tetragonal crystal content is 99% or less, the transition phase tends to become a monoclinic phase (M phase). In this case, if the average particle diameter of the crystal phase is 0.1 to 0.2 μm, the transition to the monoclinic phase is difficult to occur, and the transition to the rhombohedral phase occurs.
（実施ｆ４）
（１）Ｎ料の調合
試料Ａの原料： Ｙ２Ｏ５を主体とする安定化剤を３ｍ
ｏ１％含有するＺｒＯ２粉末にＡｌｅ’ｓ粉末とＭｇＯ
粉末を添加し、ボットミルを用いて湿式にて粉砕混合し
た後噴霧乾燥した。(Implementation f4) (1) Raw material for N material preparation sample A: 3 m of a stabilizer mainly composed of Y2O5
Ale's powder and MgO in ZrO2 powder containing o1%
The powder was added, wet-pulverized and mixed using a bot mill, and then spray-dried.
試料Ｂの原料： Ｙ２Ｏ，を主体とする安定化剤を３ｍ
０１駕含有するＺｒＯ２粉末１０％と、ＣａＯ２を主体
とする安定化剤を１２ｍｏ１％含有するＺｒ０ｚ粉末３
０ｖｔ％にＡｌ２Ｏ３粉末とＭｇＯ粉末を添加し、ポッ
トミルを用いて湿式にて粉砕混合した。Raw material for sample B: 3 m of a stabilizer mainly composed of Y2O.
Zr0z powder 3 containing 10% of ZrO2 powder containing 0.01 mole and 12 mo1% of a stabilizer mainly composed of CaO2
Al2O3 powder and MgO powder were added to 0vt% and mixed by wet grinding using a pot mill.
（２）試料の調製
各種の原料を２００ｋｇ／ｃ■２の圧力で予備成形し、
これらの予備成形物をラバープレス法にて３ ｔｏｎ／
ｃ■２の圧力で成形して６０ｓ■Ｘ ６０ｍ嘗の方形で
厚さ８■嘗の各種の角板を得た。これらの角板を１２０
０〜１３ＳＯ’Ｃで常圧焼結法、等方加圧焼結法（ＨＩ
Ｆ・・・圧力ｚｔｏｎ）にて焼成し試料とした。得られ
た焼結体にはＴ相のみが認められた。(2) Preparation of samples Various raw materials were preformed at a pressure of 200 kg/cm2,
These preforms were made into 3 ton/piece by rubber press method.
By molding at a pressure of c2, various rectangular plates measuring 60 seconds x 60 m and 8 thick were obtained. These square plates are 120
Normal pressure sintering method, isostatic pressure sintering method (HI
A sample was prepared by firing at F...pressure zton). Only T phase was observed in the obtained sintered body.
（３）研磨加工
各試料から所定の寸法の加工用試料を切り出し、ダイヤ
モンドペーストを用いて各加工用試料の全表面を所定の
表面粗度に研磨加工した。(3) Polishing Processing samples of predetermined dimensions were cut out from each sample, and the entire surface of each processing sample was polished to a predetermined surface roughness using diamond paste.
（４）アニール処理
研磨加工を施した各試料を２００°Ｃ／ｈｒで昇温し、
所定の温度に達した後同温度にて１時間保持し、その後
２００°Ｃで常温まで降下させた。(4) Each sample subjected to annealing and polishing was heated at 200°C/hr,
After reaching a predetermined temperature, it was maintained at the same temperature for 1 hour, and then lowered to room temperature at 200°C.
（５）試験
曲げ強度試験： Ｊ Ｉ ５−Ｒｌ６０１４点曲げ強
度の試験法に基づ＜ （ｋｇｆ／會■）。但し試料は４
■ＸＳ■■Ｘ４０曽諷、クロスヘメドスピード ０５■
■／■ｉｎ、上［ｘ ｔ＜ ン１０ｍｍ、 下ｆＸス
パン３０■■。(5) Test bending strength test: Based on the JI 5-Rl6014-point bending strength test method < (kgf/time). However, the sample is 4
■XS■■X40 Somage, Cross Hemed Speed 05■
■／■in, upper [x t< n10mm, lower fX span 30■■.
耐酸性： 試料およびＸ６ｖｔ％ＨＣＩ溶液を密封容器
に入れ、１５０°Ｃで２００時間放置したときの重量を
測定し、単位面積当りの重量減（■ｇ／ｃｍ２）を算出
した。但し試料はＩＳｓｍＸ １５■富の方形で厚さ３
龍。Acid resistance: The sample and the X6vt% HCI solution were placed in a sealed container and left at 150°C for 200 hours.The weight was measured and the weight loss per unit area (g/cm2) was calculated. However, the sample is ISsmX 15mm square with a thickness of 3
Dragon.
熱劣化試験：特開昭６０−３５０号公報に開示された「
セラミ、クスの試験法」に基づき、試料をオドクレープ
内の熱水中（熱水温度２５０ ’Ｃ，オートクレーブ内
の蒸気圧ｕｋｇ／ｅ■２）で５０時間熱処理シ、予めダ
イヤモンドペーストにて研磨して別表に示した表面粗度
に調整した試料の熱処理後のＸ線回折をおこない、単斜
晶の（１１１）面の回折ピークの積分強度ＩＭおよび正
方晶の（１１１）面と斜方面体晶の（１１１）面の回折
ピークの積分強度との和（ＩＴ＋ＩＲ）から、熱処理後
の単斜晶への転移率
転移率（％）＝ＩＭ／（ＩＭ＋ＩＴ＋ＩＲ）×１００
にて算出する。また、各段階におけるＲ化率をＲ化率（
％）−ＩＲ／（ＩＲ＋ＩＴ）Ｘ１００にて算出する。Thermal deterioration test: "
Based on the "Test Methods for Ceramics and Cucumbers", the sample was heat treated in hot water in an odocrape (hot water temperature 250'C, vapor pressure in the autoclave 2 kg/e) for 50 hours, and polished with diamond paste in advance. X-ray diffraction was performed on the sample after heat treatment, and the surface roughness was adjusted to the surface roughness shown in the attached table. The transition rate to monoclinic crystal after heat treatment is calculated from the sum (IT+IR) of the integrated intensity of the diffraction peak of the (111) plane as follows: Transition rate (%)=IM/(IM+IT+IR)×100. In addition, the R conversion rate at each stage is calculated as the R conversion rate (
%)-IR/(IR+IT)X100.
（６）試験結果
各試料の試験結果を別表に示すと共に、アニル処理温度
と耐酸性の関係を第１図に、同処理温度と耐熱性の関係
を第２図に、アニール処理前後のＸ線回折の結果を第３
図（ａ）、 （ｂ）にそれぞれ示す。(6) Test results The test results for each sample are shown in the attached table, and the relationship between annealing temperature and acid resistance is shown in Figure 1, and the relationship between the same treatment temperature and heat resistance is shown in Figure 2. The third diffraction result
These are shown in Figures (a) and (b), respectively.
別表から明らかなように、アニール処理をａｔことによ
り各試料の曲げ強度は若干低下し、その強度低下はアニ
ール処理温度が高くなるに伴い漸次増大する。耐酸性お
よび耐熱性（熱劣化転移率）は漸次向上する。箪１図お
よび第２図のグラフは試験Ｎｏ、 １− Ｎｏ、 １７
の結果を示しているが、これらの結果から判断すればア
ニール処理温度が５００’Ｃ以上で焼成温度以下の場合
に耐酸性および耐熱性共に著しく向上している。なお、
耐酸性に関しては、表面粗ｌ１ｌｉ：（Ｒｍａｘ）が小
さい方が向上する傾向にある。第３図（８）、 （ｂ）
のグラフは試験１１０．１８゜Ｎ０１９の結果、すなわ
ち焼成温度１３００°Ｃ１表面粗度３．０μの試料にお
けるアニール処理（処理温度１２５０゛Ｃ５１時間）前
後のＸ線回折ピークを示している。As is clear from the attached table, the bending strength of each sample is slightly reduced by the annealing treatment, and the decrease in strength gradually increases as the annealing temperature increases. Acid resistance and heat resistance (thermal deterioration transition rate) gradually improve. The graphs in Figures 1 and 2 are test No. 1- No. 17
Judging from these results, both acid resistance and heat resistance are significantly improved when the annealing temperature is 500'C or higher and lower than the firing temperature. In addition,
Regarding acid resistance, the smaller the surface roughness l1li:(Rmax), the better it tends to be. Figure 3 (8), (b)
The graph shows the results of test 110.18°N019, that is, the X-ray diffraction peaks before and after annealing treatment (processing temperature 1250°C for 51 hours) for a sample with a firing temperature of 1300°C and a surface roughness of 3.0μ.
各試料においては表面の研磨加工により同表面にＲ相の
生成が認められるが、アニール処理によりＲ相が消失し
てＴ相の割合が著しく増大していることがわかる。上記
した範囲の温度でのアニール処理により、正方晶の割合
が９９％以上となる。In each sample, the formation of an R phase is observed on the surface due to surface polishing, but it can be seen that the R phase disappears due to the annealing treatment and the proportion of the T phase increases significantly. By annealing at a temperature within the above range, the proportion of tetragonal crystals becomes 99% or more.
（以下余白）(Margin below)
第１図はアニール処理温度と耐酸性の関係を示すグラフ
、第２図は同処理温度と耐熱性の関係を示すグラフ、第
３図は（ａ）、 （ｂ）ｉｔアニール処理前後のＸ線回
折ピークを示すグラフである。Figure 1 is a graph showing the relationship between annealing temperature and acid resistance, Figure 2 is a graph showing the relationship between annealing temperature and heat resistance, and Figure 3 is (a) and (b) X-rays before and after it annealing. It is a graph showing diffraction peaks.
Claims (1)
ニア焼結体からなる高耐酸性の高強度ジルコニアセラミ
ックスの製造方法であり、焼結体を研磨加工した後５０
０℃以上でかつ焼成温度以下の温度でアニール処理を施
すことを特徴とする高耐酸性の高強度ジルコニアセラミ
ックスの製造方法。This is a method for producing highly acid-resistant, high-strength zirconia ceramics made of a zirconia sintered body composed of 99% or more of tetragonal zirconia phase, and after polishing the sintered body,
A method for producing highly acid-resistant and high-strength zirconia ceramics, characterized by performing an annealing treatment at a temperature of 0° C. or higher and lower than the firing temperature.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2129846A JPH0426546A (en) | 1990-05-18 | 1990-05-18 | Production of high strength zirconia ceramics having high acid resistance |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2129846A JPH0426546A (en) | 1990-05-18 | 1990-05-18 | Production of high strength zirconia ceramics having high acid resistance |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0426546A true JPH0426546A (en) | 1992-01-29 |
Family
ID=15019687
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2129846A Pending JPH0426546A (en) | 1990-05-18 | 1990-05-18 | Production of high strength zirconia ceramics having high acid resistance |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0426546A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0846667A3 (en) * | 1996-12-05 | 1999-01-27 | Ngk Insulators, Ltd. | Ceramic parts and a producing process thereof |
| JP2010034212A (en) * | 2008-07-28 | 2010-02-12 | Toshiba Corp | High-frequency ceramic package and method of fabricating the same |
-
1990
- 1990-05-18 JP JP2129846A patent/JPH0426546A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0846667A3 (en) * | 1996-12-05 | 1999-01-27 | Ngk Insulators, Ltd. | Ceramic parts and a producing process thereof |
| US6258440B1 (en) | 1996-12-05 | 2001-07-10 | Ngk Insulators, Ltd. | Ceramic parts and a producing process thereof |
| JP2010034212A (en) * | 2008-07-28 | 2010-02-12 | Toshiba Corp | High-frequency ceramic package and method of fabricating the same |
| US8476755B2 (en) | 2008-07-28 | 2013-07-02 | Kabushiki Kaisha Toshiba | High frequency ceramic package and fabrication method for the same |
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