JPH0323283A - Formation of oxidation preventing film for conductive nonoxide-based ceramic - Google Patents
Formation of oxidation preventing film for conductive nonoxide-based ceramicInfo
- Publication number
- JPH0323283A JPH0323283A JP15566889A JP15566889A JPH0323283A JP H0323283 A JPH0323283 A JP H0323283A JP 15566889 A JP15566889 A JP 15566889A JP 15566889 A JP15566889 A JP 15566889A JP H0323283 A JPH0323283 A JP H0323283A
- Authority
- JP
- Japan
- Prior art keywords
- ceramic
- oxidation
- film
- conductive
- oxide film
- 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
- 239000000919 ceramic Substances 0.000 title claims abstract description 25
- 230000003647 oxidation Effects 0.000 title abstract description 16
- 238000007254 oxidation reaction Methods 0.000 title abstract description 16
- 230000015572 biosynthetic process Effects 0.000 title description 2
- 230000002378 acidificating effect Effects 0.000 claims abstract description 9
- 239000007864 aqueous solution Substances 0.000 claims description 14
- 239000011225 non-oxide ceramic Substances 0.000 claims description 10
- 229910052575 non-oxide ceramic Inorganic materials 0.000 claims description 10
- 239000003963 antioxidant agent Substances 0.000 claims description 8
- 230000003078 antioxidant effect Effects 0.000 claims description 8
- 238000004519 manufacturing process Methods 0.000 claims description 4
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 abstract description 6
- 238000007598 dipping method Methods 0.000 abstract 1
- 238000000034 method Methods 0.000 description 14
- 239000000463 material Substances 0.000 description 11
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 239000002585 base Substances 0.000 description 5
- 239000011248 coating agent Substances 0.000 description 5
- 238000000576 coating method Methods 0.000 description 5
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 239000000523 sample Substances 0.000 description 4
- 239000011521 glass Substances 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 230000003064 anti-oxidating effect Effects 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 230000008646 thermal stress Effects 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 241000270666 Testudines Species 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- KCQLSIKUOYWBAO-UHFFFAOYSA-N azaborinine Chemical compound B1=NC=CC=C1 KCQLSIKUOYWBAO-UHFFFAOYSA-N 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 239000000920 calcium hydroxide Substances 0.000 description 1
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 1
- 239000010406 cathode material Substances 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 1
- 239000010452 phosphate Substances 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 235000019353 potassium silicate Nutrition 0.000 description 1
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 1
- 238000004901 spalling Methods 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 230000004584 weight gain Effects 0.000 description 1
- 235000019786 weight gain Nutrition 0.000 description 1
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明は導電性非酸化物系セラミックスを高温酸化雰囲
気で使用する際の酸化防止として事前に酸化皮膜を生成
し、使用中の酸化を防止することにより耐用性を向上さ
せることができる方法に関するものである。[Detailed Description of the Invention] [Industrial Application Field] The present invention creates an oxide film in advance to prevent oxidation when using conductive non-oxide ceramics in a high-temperature oxidizing atmosphere to prevent oxidation during use. The present invention relates to a method for improving durability.
［従来の技術］
？来、ＳｉＣ，ＴｉＮ，ＴｉＧ．ＺｒＢ■．Ｃｒ，．Ｃ
２，＾１２０．−Ｃ系セラミックス等の非酸化物系セラ
ミックスの酸化防止方法としては■特公昭５３−２３３
２７号公報に提案されるようにＳｉｎ２、金属Ｓｉ、リ
ン酸塩、Ｂ２０，および水ガラスなどから成るガラス系
のゆう薬をはけぬりし乾燥させ酸化防止膜を形成させた
り、■バーナなどを用いて表面をあぶり酸化皮膜を事前
に生成することにより、高温酸化雰囲気での酸化を防止
し母材の耐用性向上を図っている。[Conventional technology]? Since then, SiC, TiN, TiG. ZrB ■. Cr,. C
2, ^120. - As a method for preventing oxidation of non-oxide ceramics such as C-based ceramics, ■Special Publication No. 53-233
As proposed in Publication No. 27, a glass-based powder made of Sin2, metal Si, phosphate, B20, water glass, etc. is brushed off and dried to form an oxidation-preventing film, and burners, etc. By using this method to burn the surface and generate an oxide film in advance, oxidation in high-temperature oxidizing atmospheres is prevented and the durability of the base material is improved.
［発明が解決しようとする３題］
しかしながら上記■の方法は、材料表面温度が被覆材の
融点を超えた場合被覆材の収縮および母材との濡れ性等
の点から、被覆材が均一に母材を覆うことができなかっ
たり、塗布時間気孔内部まで被覆材が十分侵入出来ない
ので、直接大気と接し酸化が生じその効果を発揮しない
。仮に、ガラス系のゆう薬が使用時において均−に形成
されたとしても、酸素がこの膜内を拡散し母材の酸化が
進行する。また、■の方法はバーナスポット部の酸化膜
が厚く、最大の難点は大型品あるいは複雑形状品の場合
、熱応力等の集中によりスポールが発生する。[Three Problems to be Solved by the Invention] However, in the method (2) above, the coating material cannot be uniformly coated due to shrinkage of the coating material and wettability with the base material when the material surface temperature exceeds the melting point of the coating material. Since the base material cannot be covered or the coating material cannot sufficiently penetrate into the pores during application, it comes into direct contact with the atmosphere and oxidizes, making it ineffective. Even if a glass-based powder is formed uniformly during use, oxygen will diffuse within this film and oxidation of the base material will progress. In addition, the method (2) has a thick oxide film at the burner spot, and the biggest drawback is that in the case of large products or products with complex shapes, spalls occur due to concentration of thermal stress, etc.
［課題を解決するための手段］
本発明は、以上の課題を解決する酸化防止皮膜生成方法
を提供するものであり、その要旨は次のとおりである。[Means for Solving the Problems] The present invention provides a method for producing an antioxidant film that solves the above problems, and the gist thereof is as follows.
導電性非酸化物系セラミックスをＩＪ極として酸性また
はアルカリ性水溶液中に浸漬し、上記水溶液中に浸漬し
た陰極との間に電圧を印加することにより、上記セラミ
ックスの表面に均一に酸化皮膜を生成させることを特徴
とする導電性非酸化物系セラミックスの酸化防止膜生成
方法。A conductive non-oxide ceramic is immersed in an acidic or alkaline aqueous solution as an IJ electrode, and a voltage is applied between it and a cathode immersed in the aqueous solution to uniformly generate an oxide film on the surface of the ceramic. A method for producing an antioxidant film on conductive non-oxide ceramics, characterized by:
なお、陰極材料としては、耐酸性或は耐アルカリ性のも
のでイオン化傾向の小さい白金板等が最適であるが、通
電時間が短いのでＳＵＳ棒等で十分である。酸性水溶液
としては、希硫酸溶液、希塩酸溶液、アルカリ溶液とし
ては、水酸化ナトリウム、水酸化カルシウム溶液等が考
えられるが、陽極に酸素が発生する電解水溶液であれば
良い。As the cathode material, a platinum plate or the like, which is acid- or alkali-resistant and has a small tendency to ionize, is optimal, but a SUS rod or the like is sufficient because the current application time is short. Examples of the acidic aqueous solution include a dilute sulfuric acid solution and a dilute hydrochloric acid solution, and examples of the alkaline solution include sodium hydroxide and calcium hydroxide solutions, but any electrolytic aqueous solution that generates oxygen at the anode may be used.
［作用］
本発明による酸化防止皮膜生成方法は、導電性非酸化物
系セラミックスを陽極として上記水溶液中Ｃ浸漬し、上
記水溶液中に浸消した陰極との間に電圧を印加するため
、導電性のある非酸化物が表面に存在するかぎり電流が
流れ、酸化皮膜が全面に均一に生成するまで処理するこ
とができる。[Function] In the method for producing an antioxidant film according to the present invention, a conductive non-oxide ceramic is immersed in C in the aqueous solution as an anode, and a voltage is applied between the cathode immersed in the aqueous solution. As long as a certain non-oxide is present on the surface, a current will flow and the treatment can be carried out until an oxide film is uniformly formed over the entire surface.
そのため母材表面の酸化膜のむらがなく、また酸性また
はアルカリ性水溶液が侵入する開気孔の表面まで均一に
酸化皮膜を生成することができる。Therefore, there is no unevenness of the oxide film on the surface of the base material, and the oxide film can be uniformly formed even on the surface of the open pores into which the acidic or alkaline aqueous solution enters.
さらに本方法での酸化皮膜の厚みは非常に薄く，かつ酸
化防止皮膜が均一に形成されるので酸化防止皮膜として
の機能を十分に発揮できる。また、大型品あるいは複雑
形状品でも酸性またはアルカリ性水溶液中に浸漬出来れ
ば、簡単に酸化防止皮膜を生成でき熱応力等によるスポ
ールについても心配する必要がない。Furthermore, the thickness of the oxidized film in this method is very thin and the oxidation-preventing film is formed uniformly, so that it can fully exhibit its function as an oxidation-preventing film. Furthermore, if even large products or products with complex shapes can be immersed in an acidic or alkaline aqueous solution, an antioxidant film can be easily formed, and there is no need to worry about spalling caused by thermal stress or the like.
［実施例］
（実施例１）
以下にこの発明の具体例を詳細に説明する。導電性非酸
化物系セラミックスとしてＳｉＣ系セラミックについて
本発明による方法で酸化皮膜の生成を実施した。第１図
に示すように、硫酸濃度５％の酸性水溶液４にＳｉｃ系
セラミック棒２ （３０ｍ−φｘ ４００ｍｓ ）及び
ＳＵＳ棒３を浸漬し、ＳｊＣ系セラミック棒２が陽極、
ＳＵＳ棒３が陰極となるように直流定電圧発生装置１に
接続した。モして５ｖ・２０Ａ程度の電流を流した。第
２図にその際の電流値の変化を示しているが、約５分間
で電流が流れなくなり、セラミック棒２の表面が酸化膜
で覆われたことを示している。処理中にＳｉＣ系セラミ
ック棒２の表面は白っぽく変化し、酸化皮膜の生成が確
認できた。処理後のセラミック棒２の断面を観察したと
ころ、酸化膜が約１００μ一の厚みで均一に生成してい
た。[Example] (Example 1) A specific example of the present invention will be described in detail below. An oxide film was formed on a SiC ceramic as a conductive non-oxide ceramic by the method according to the present invention. As shown in FIG. 1, a SiC ceramic rod 2 (30m-φx 400ms) and a SUS rod 3 are immersed in an acidic aqueous solution 4 with a sulfuric acid concentration of 5%, and the SJC ceramic rod 2 serves as an anode;
The SUS rod 3 was connected to the DC constant voltage generator 1 so as to serve as a cathode. A current of about 5V and 20A was applied. FIG. 2 shows the change in current value at that time, which shows that the current stopped flowing after about 5 minutes, indicating that the surface of the ceramic rod 2 was covered with an oxide film. During the treatment, the surface of the SiC ceramic rod 2 turned whitish, and the formation of an oxide film was confirmed. When the cross section of the ceramic rod 2 after the treatment was observed, an oxide film was formed uniformly with a thickness of about 100 μm.
次に、厚さ１００ｕ−の酸化膜を形成したＳｉＣ系セラ
ミック棒（本発明品）について酸化測定温度１４００℃
、酸化時間２時間、大気雰囲気の条件下で耐酸化性につ
いて測定した。測定項目としては、酸化増量、試料断面
の酸化膜厚みを取り上げた。Next, the oxidation measurement temperature was 1400°C for the SiC ceramic rod (product of the present invention) on which an oxide film with a thickness of 100 μ- was formed.
The oxidation resistance was measured under atmospheric conditions with an oxidation time of 2 hours. The measurement items included oxidation weight gain and oxide film thickness on the cross section of the sample.
その結果を第１表に示す。尚、第１表には第２表に示す
組成（ｗｔ亀）のガラス系のゆう薬を塗布し、１２０℃
で乾燥させて５００μ−の酸化防止皮膜を形成させたＳ
ｉＣ系セラミック棒（従来品）及び何ら表面処理しない
ＳｉＣ系セラミック棒（未処理品）の上記耐酸化性につ
いても併記した。The results are shown in Table 1. In addition, a glass-based powder with the composition shown in Table 2 (wt turtle) was applied to Table 1, and heated at 120°C.
S dried to form a 500μ-thick anti-oxidation film
The above oxidation resistance of the iC ceramic rod (conventional product) and the SiC ceramic rod without any surface treatment (untreated product) is also described.
第１表
第２表
第１表より明らかなように本発明による酸化皮膜の母材
への酸化防止効果は非常に良好である。As is clear from Table 1, Table 2, and Table 1, the oxidation-preventing effect of the oxide film according to the present invention on the base material is very good.
また、試験後の試刺断而を観察した結果でも、本発明に
よる酸化防止皮膜を生成させたものはほとんど酸化の進
行は見られなかった。Further, as a result of observing the test specimens after the test, almost no progress of oxidation was observed in the specimens on which the oxidation-preventing film of the present invention was formed.
（実施例２）
複雑形状品として内径３０開、外径４０ＩＩＩ１、曲率
７０１■、ストレート部２００ａ＋ｍのＴｉＮセラミッ
ク製υ字バイブについて検討した。酸化防止皮膜生成方
法として、本発明による方法と、バーナによる方法とを
比較した。ＴｉＮセラミック製Ｕ字バイブな５％水酸化
ナトリウム水溶液に浸漬し、上記実施例！と同様に５ｖ
・２０Ａ程度の電流を流した。約数分後に電流が流れな
くなり、試料を観察した結果、内・外面とも白色化し、
均一に酸化防止膜が形成されていた。また断面観察の結
果、酸化膜の厚みは１００ ｕｖｓ程度であり均−であ
った。(Example 2) A TiN ceramic υ-shaped vibrator with an inner diameter of 30 mm, an outer diameter of 40 mm, a curvature of 701 mm, and a straight portion of 200 a+m was studied as a complex-shaped product. The method according to the present invention and the method using a burner were compared as methods for producing an antioxidant film. The above example is a TiN ceramic U-shaped vibe immersed in a 5% sodium hydroxide aqueous solution! Similarly, 5v
・A current of about 20A was applied. After about a few minutes, the current stopped flowing, and as a result of observing the sample, both the inner and outer surfaces turned white.
An anti-oxidation film was formed uniformly. Further, as a result of cross-sectional observation, the thickness of the oxide film was about 100 uvs, which was uniform.
次にエアープロバンパーナ（５ Ｎｓ３／ｌ｛ｒ）を用
いて、ＴｉＮセラミック′ＩＩＡＵ字バイブの表面をあ
ぶり酸化膜を生成した。処理後のＴｉＮセラミック製Ｕ
字バイブの表面を観察した結果、無数のへアークラック
が確認できた。また断面ｗＡ察の結果、酸化膜の厚みは
、１０μ一から８００μ一とぼらつレ）でいた。Next, using an air probe burner (5 Ns3/l{r), the surface of the TiN ceramic 'IIAU-shaped vibrator was burnt to form an oxide film. TiN ceramic U after treatment
As a result of observing the surface of the vibrator, countless hair cracks were confirmed. Further, as a result of cross-sectional inspection, the thickness of the oxide film was irregular, ranging from 10 μm to 800 μm.
［発明の効果］
以上詳述したように本発明の導電性非酸化物系セラミッ
クスの酸化防止皮膜生戒方法として、導電性非酸化物系
セラミックスを陽極として酸性またはアルカリ性水溶液
中に浸漬し、上記水溶液中に浸漬した陰極との間に電圧
を印加することにより、上記セラミックスの表面に均−
・に酸化ｎｑを生成させる方法を用いることにより、便
川中の酸化を大幅に改善することができ、また熱処理工
程がないため大型品・複雑形状品を容易に亀裂発生する
ことなく酸化防止皮膜を生成することができる。[Effects of the Invention] As detailed above, as the method for preserving the antioxidant coating of conductive non-oxide ceramics of the present invention, the conductive non-oxide ceramics is immersed as an anode in an acidic or alkaline aqueous solution. By applying a voltage between the cathode and the cathode immersed in an aqueous solution, the surface of the ceramic is uniformly applied.
・By using a method that generates oxidized nq, it is possible to significantly improve oxidation in the river, and since there is no heat treatment process, it is possible to easily coat large products and complex-shaped products without cracking. can be generated.
第１図は、本発明の酸化防止皮膜の生成ノＪ′法、第２
図は試験サンプルに本発明の処理を通用した場合の電流
値の変化を示したものである。Figure 1 shows the J' method of forming the antioxidant film of the present invention,
The figure shows the change in current value when a test sample is subjected to the treatment of the present invention.
Claims (1)
たはアルカリ性水溶液中に浸漬し上記水溶液中に浸漬し
た陰極との間に電圧を印加することにより、上記セラミ
ックスの表面に均一に酸化膜を生成させることを特徴と
する導電性非酸化物系セラミックスの酸化防止皮膜生成
方法。1. A conductive non-oxide ceramic is immersed in an acidic or alkaline aqueous solution as an anode, and a voltage is applied between the cathode immersed in the aqueous solution and a uniform oxide film is generated on the surface of the ceramic. A method for producing an antioxidant film on conductive non-oxide ceramics, characterized by:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15566889A JPH0323283A (en) | 1989-06-20 | 1989-06-20 | Formation of oxidation preventing film for conductive nonoxide-based ceramic |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15566889A JPH0323283A (en) | 1989-06-20 | 1989-06-20 | Formation of oxidation preventing film for conductive nonoxide-based ceramic |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0323283A true JPH0323283A (en) | 1991-01-31 |
Family
ID=15610980
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15566889A Pending JPH0323283A (en) | 1989-06-20 | 1989-06-20 | Formation of oxidation preventing film for conductive nonoxide-based ceramic |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0323283A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002040423A1 (en) * | 2000-11-17 | 2002-05-23 | Ngk Insulators,Ltd. | Silicon carbide based porous article and method for preparing the same |
-
1989
- 1989-06-20 JP JP15566889A patent/JPH0323283A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002040423A1 (en) * | 2000-11-17 | 2002-05-23 | Ngk Insulators,Ltd. | Silicon carbide based porous article and method for preparing the same |
| JP2002154882A (en) * | 2000-11-17 | 2002-05-28 | Ngk Insulators Ltd | Silicon carbide porous body and method for producing the same |
| US6777114B2 (en) | 2000-11-17 | 2004-08-17 | Ngk Insulators, Ltd. | Silicon carbide-based porous body and process for production thereof |
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