JPH0611665B2 - Dense Al 2) O 2 3) -Cr 2) O 2 3) Sintered body manufacturing method - Google Patents
Dense Al 2) O 2 3) -Cr 2) O 2 3) Sintered body manufacturing methodInfo
- Publication number
- JPH0611665B2 JPH0611665B2 JP2003387A JP338790A JPH0611665B2 JP H0611665 B2 JPH0611665 B2 JP H0611665B2 JP 2003387 A JP2003387 A JP 2003387A JP 338790 A JP338790 A JP 338790A JP H0611665 B2 JPH0611665 B2 JP H0611665B2
- Authority
- JP
- Japan
- Prior art keywords
- sintered body
- dense
- weight
- oxide
- body manufacturing
- 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
Links
Landscapes
- 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、緻密質高耐食性Al2O3−Cr2O3焼結体の製造方
法に関する。TECHNICAL FIELD The present invention relates to a method for producing a dense and highly corrosion resistant Al 2 O 3 —Cr 2 O 3 sintered body.
従来の技術 従来、Al2O3系焼結体は、耐食性に優れているので、鉄
鋼業の耐火物等多方面への応用が試みられてきた。しか
し、近年のファインセラミックスの発展に伴いより厳し
い環境下では、Al2O3系焼結体より更に高耐食性を有す
るZrO2が使用されるようになってきた。 2. Description of the Related Art Conventionally, Al 2 O 3 based sintered bodies have been excellent in corrosion resistance, so that application to various fields such as refractory materials in the steel industry has been tried. However, with the recent development of fine ceramics, ZrO 2 having higher corrosion resistance than the Al 2 O 3 based sintered body has come to be used in a more severe environment.
発明が解決しようとする課題 Al2O3系焼結体にCr2O3を添加した場合、単なるAl2O3に
比べて、耐熱性、耐食性、硬度が向上することが期待さ
れる。しかし、Cr2O3成分の高温で蒸発し易さのため
に、緻密に焼結することが困難である。Cr2O3単味の場
合、炭素粉末中という還元条件下で焼結させると、相対
密度の97％近くまで緻密化することは、窯業協会誌、VO
L88、P184〜P190に報告されているが、Al2O3とCr2O3の
混合粉末法で焼結した場合には、あまり緻密化しないこ
とが、窯業協会誌、VOL90、P68〜P73に報告されてい
る。Problems to be Solved by the Invention When Cr 2 O 3 is added to an Al 2 O 3 system sintered body, heat resistance, corrosion resistance, and hardness are expected to be improved as compared with simple Al 2 O 3 . However, it is difficult to sinter densely because the Cr 2 O 3 component easily evaporates at high temperature. In the case of Cr 2 O 3 alone, when sintered under reducing conditions such as carbon powder, it is possible to densify up to 97% of the relative density.
L88, P184 to P190 have been reported, but when sintered by the mixed powder method of Al 2 O 3 and Cr 2 O 3 , it is not densified so much, according to the Society of Ceramic Engineers, VOL90, P68 to P73. It has been reported.
また、Al2O3−Cr2O3固溶体粉末をアンモニウム水溶液か
ら熱分解法で作ったのち、炭素粉末中で焼成すると緻密
化するという報告が、昭和62年度窯業協会年会予稿集P4
43〜P444に記載されているが、大気中では、緻密質焼結
体を得ることはできていない。In addition, a report that the Al 2 O 3 -Cr 2 O 3 solid solution powder was densified by firing it in carbon powder after making it by thermal decomposition method from ammonium aqueous solution was published in 1987, Ceramic Industry Association Annual Meeting Proceeding P4.
43 to P444, it is not possible to obtain a dense sintered body in the atmosphere.
本発明は、苛酷な環境下でも充分な耐用が得られる高耐
食性Al2O3−Cr2O3緻密質焼結体の大気中での製造方法を
提供しようとするものである。The present invention is intended to provide a method for producing a highly corrosion-resistant Al 2 O 3 —Cr 2 O 3 dense sintered body in the atmosphere, which can obtain sufficient durability even in a harsh environment.
課題を解決するための手段 本発明は、元来高耐食性を有するが難焼結性材料である
Cr2O3とAl2O3の緻密質固溶体を大気中雰囲気で生成さ
せ、高耐食性化を図るものである。Means for Solving the Problems The present invention is a material which originally has high corrosion resistance but is hardly sintered.
A dense solid solution of Cr 2 O 3 and Al 2 O 3 is generated in the atmosphere to improve the corrosion resistance.
以下、本発明の製造方法について説明する。Hereinafter, the manufacturing method of the present invention will be described.
本発明は高耐食性Al2O3−Cr2O3の製造方法は、酸化アル
ミニウム70〜50重量％、酸化クロミウム30〜50重量％か
らなる原料を用い、焼結助剤として、酸化チタニウム或
は滑石（3MgO・4SiO2・H2O）を外掛1.5重量％以下添加し
大気雰囲気中で焼成することを特徴とするものである。Production method of the present invention is highly corrosion-resistant Al 2 O 3 -Cr 2 O 3 is aluminum oxide 70 to 50 wt%, using a raw material consisting of chromium oxide 30 to 50 wt%, as a sintering agent, titanium oxide or The feature is that talc (3MgO ・ 4SiO 2・ H 2 O) is added in an external amount of 1.5% by weight or less and fired in an air atmosphere.
ここで、出発原料である酸化アルミニウム、酸化クロミ
ニウム、酸化チタニウム、滑石の純度は、市販品の程度
のものでよい。粒度は５μｍ以下のものが望ましい。こ
れらの原料を所定の量比で混合し、1500〜1600℃で焼成
すれば高耐食性を有し、緻密質なAl2O3−Cr2O3焼結体が
えられる。Here, the purity of aluminum oxide, chromium oxide, titanium oxide, and talc, which are the starting materials, may be on the order of commercial products. The particle size is preferably 5 μm or less. If these raw materials are mixed in a predetermined amount ratio and fired at 1500 to 1600 ° C., a dense Al 2 O 3 —Cr 2 O 3 sintered body having high corrosion resistance can be obtained.
以下に、数値限定の理由についてのべる。The reasons for the numerical limitation are given below.
まず、Al2O3とCr2O3粉体を表１に示す組成比で混合し、
大気中1700℃、４時間の焼成実験を行った。表１におな
じく得られた相対密度も示す。First, Al 2 O 3 and Cr 2 O 3 powder were mixed in the composition ratio shown in Table 1,
A firing experiment was carried out in air at 1700 ° C. for 4 hours. Also shown in Table 1 are the relative densities obtained.
NO.４〜７のCr2O3を30％以上含有した系では、相対密度
が70％以下の多孔質な焼結体しか、えることができなか
った。 In the system containing 30% or more of Cr 2 O 3 of NO. 4 to 7, only a porous sintered body having a relative density of 70% or less could be obtained.
そこで、これらCr2O3を30％以上の組成の緻密質焼結体
を得る目的で焼結助剤の検討を実施した。焼結助剤とし
ては、Al2O3の液相焼結助剤として使用されている酸化
チタニウムと滑石を検討した。これらの焼結助剤を外掛
0.5wt%、1.0wt%、1.5wt%、2.0wt%添加し1500℃、４時間
大気雰囲気中で焼成を行った。結果を表２〜３に示す。Therefore, the sintering aid was studied for the purpose of obtaining a dense sintered body having a composition of 30% or more of Cr 2 O 3 . As a sintering aid, titanium oxide and talc used as a liquid phase sintering aid for Al 2 O 3 were examined. Applying these sintering aids
0.5 wt%, 1.0 wt%, 1.5 wt% and 2.0 wt% were added, and firing was performed at 1500 ° C. for 4 hours in the atmosphere. The results are shown in Tables 2-3.
以上の結果より、Cr2O3含有量が30〜50wt％以下の組成
で、酸化チタニウム或は滑石を1.5wt％以下添加した系
では、焼結の目安とされている95％以上の相対密度が得
られ焼結が殆ど完了していることがわかる。 From the above results, in a system with Cr 2 O 3 content of 30 to 50 wt% or less and titanium oxide or talc added to 1.5 wt% or less, relative density of 95% or more, which is a standard for sintering, It is found that the sintering is almost completed.
一方、Cr2O3含有量が60wt％になると、本検討焼結助剤
では緻密化を図ることができなかった。また、焼結助剤
の量を2.0wt％まで添加すると、比較的低温から大量の
液相が生成し、初期焼結は進み易いが、Al2O3とCr2O3の
固溶体反応を阻害する傾向が認められ緻密化に至らなか
ったものと推定される。On the other hand, when the Cr 2 O 3 content was 60 wt%, densification could not be achieved with the sintering aid of this study. In addition, when the amount of sintering aid is added up to 2.0 wt%, a large amount of liquid phase is generated from a relatively low temperature and the initial sintering is easy to proceed, but it inhibits the solid solution reaction of Al 2 O 3 and Cr 2 O 3. It is highly probable that the densification did not lead to densification.
次に、40mmφ×30mmφ×100mmサイズ底のあるルツボ形
状の各種焼結体を用い、耐食性の試験を実施した。実験
条件としては、焼結体のスポール防止を考えて1500℃ま
で充分予熱を行った後、1600℃の溶綱中に36時間浸漬し
溶損量を調査した。溶鋼成分を表４に、実験結果を表５
に示す。Next, a corrosion resistance test was performed using various crucible-shaped sintered bodies having a 40 mmφ × 30 mmφ × 100 mm size bottom. As an experimental condition, in consideration of spall prevention of the sintered body, after sufficiently preheating up to 1500 ° C, it was immersed in a molten steel at 1600 ° C for 36 hours to examine the amount of melting loss. Table 4 shows the molten steel components and Table 5 shows the experimental results.
Shown in.
本製造方法で得られたCr2O3量が30〜50％、残部がAl2O3
からなる相対密度が97％以上の焼結体は溶鋼にたいし、
ZrO2系に比較しても高耐食性であることが判明した。 The amount of Cr 2 O 3 obtained by this production method is 30 to 50%, and the balance is Al 2 O 3
Sintered bodies with a relative density of 97% or more are
It was found that the corrosion resistance is higher than that of the ZrO 2 system.
酸化アルミニウム70〜50重量％、酸化クロミウム30〜50
重量％からなる原料を用い、焼結助剤として、酸化チタ
ニウム或は滑石（3MgO・4SiO2・H2O）を外掛1.5重量％
以下添加し、大気雰囲気中で1500〜1600℃で焼成すれ
ば、緻密な高耐食性Al2O3−Cr2O3焼結体がえられる。Aluminum oxide 70-50% by weight, chromium oxide 30-50
1.5% by weight of titanium oxide or talc (3MgO ・ 4SiO 2・ H 2 O) as a sintering aid
If added and fired at 1500 to 1600 ° C. in the air atmosphere, a dense and highly corrosion resistant Al 2 O 3 —Cr 2 O 3 sintered body can be obtained.
実施例 実施例１ 平均粒径0.5μｍの酸化アルミニウム及び酸化クロミウ
ムを重量比５：５の割合で秤量し、その後酸化チタニウ
ムを秤量重量にたいし外掛1.0％の重量を添加しボール
ミルで約24時間粉砕混合し、供試粉体を試作した。つい
で、65×65×10mmにcold isostatic pressを1.2ton/cm2
の圧力で行った後、この圧粉体を大気中1500℃で４時間
焼成し、相対密度99％の焼結体を得た。Example Example 1 Aluminum oxide and chromium oxide having an average particle size of 0.5 μm were weighed in a weight ratio of 5: 5, and then titanium oxide was added to the weighed weight of 1.0% to the weighed weight, followed by a ball mill for about 24 hours. It was pulverized and mixed, and a test powder was manufactured as a trial. Then, a cold isostatic press with a size of 65 × 65 × 10 mm is 1.2ton / cm 2
Then, the green compact was fired in the air at 1500 ° C. for 4 hours to obtain a sintered body having a relative density of 99%.
比較例１ 平均粒径0.5μｍの酸化アルミニウム及び酸化クロミウ
ムを重量比５：５の割合で秤量し、ボールミルで約24時
間粉砕混合し、供試粉体を試作した。ついで、65×65×
10mmにcold isostatic pressを1.2ton/cm2の圧力で行っ
た後、この圧粉体を大気中1600℃で４時間焼成したが、
相対密度は82％であった。Comparative Example 1 Aluminum oxide and chromium oxide having an average particle size of 0.5 μm were weighed in a weight ratio of 5: 5, and pulverized and mixed in a ball mill for about 24 hours to prepare a test powder. Then, 65 × 65 ×
After performing a cold isostatic press on 10 mm at a pressure of 1.2 ton / cm 2 , the green compact was fired at 1600 ° C for 4 hours in the air
The relative density was 82%.
発明の効果 以上の結果から明らかなごとく、本発明の方法を用いれ
ば、緻密質高耐食性Al2O3−Cr2O3焼結体が大気中で容易
にえられる。EFFECTS OF THE INVENTION As is clear from the above results, by using the method of the present invention, a dense and highly corrosion-resistant Al 2 O 3 —Cr 2 O 3 sintered body can be easily obtained in the atmosphere.
Claims (1)
ミウム30〜50重量％からなる原料を用い、焼結助剤とし
て、酸化チタニウム或は滑石（3MgO・4SiO2・H2O）を外掛
1.5重量％以下添加し、大気雰囲気中で焼成することを
特徴とする緻密質高耐食性Al2O3−Cr2O3焼結体の製造方
法。1. A raw material consisting of 70 to 50% by weight of aluminum oxide and 30 to 50% by weight of chromium oxide is used, and titanium oxide or talc (3MgO.4SiO 2 .H 2 O) is externally applied as a sintering aid.
A method for producing a dense and highly corrosion-resistant Al 2 O 3 —Cr 2 O 3 sintered body, which comprises adding 1.5 wt% or less and firing in an air atmosphere.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003387A JPH0611665B2 (en) | 1990-01-12 | 1990-01-12 | Dense Al 2) O 2 3) -Cr 2) O 2 3) Sintered body manufacturing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003387A JPH0611665B2 (en) | 1990-01-12 | 1990-01-12 | Dense Al 2) O 2 3) -Cr 2) O 2 3) Sintered body manufacturing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03208863A JPH03208863A (en) | 1991-09-12 |
| JPH0611665B2 true JPH0611665B2 (en) | 1994-02-16 |
Family
ID=11555952
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2003387A Expired - Lifetime JPH0611665B2 (en) | 1990-01-12 | 1990-01-12 | Dense Al 2) O 2 3) -Cr 2) O 2 3) Sintered body manufacturing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0611665B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3930143B2 (en) | 1998-04-28 | 2007-06-13 | 三菱重工業株式会社 | Method for producing chromia-alumina sintered body |
| FR2918659B1 (en) * | 2007-07-11 | 2011-11-11 | Saint Gobain Ct Recherches | FRITTE PRODUCT BASED ON ALUMINA AND CHROME OXIDE. |
-
1990
- 1990-01-12 JP JP2003387A patent/JPH0611665B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH03208863A (en) | 1991-09-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPS5924751B2 (en) | Sintered shaped body | |
| JPH07277814A (en) | Alumina-based ceramic sintered compact | |
| JPS5860677A (en) | Manufacture of high tenacity silicon nitride sintered body | |
| JP2829229B2 (en) | Silicon nitride ceramic sintered body | |
| JP2507479B2 (en) | SiC-Al Lower 2 O Lower 3 Composite Sintered Body and Manufacturing Method Thereof | |
| JPH05221728A (en) | Silicon nitride ceramics | |
| US5308561A (en) | Process for production of a Si3 N4, based material | |
| JPH0611665B2 (en) | Dense Al 2) O 2 3) -Cr 2) O 2 3) Sintered body manufacturing method | |
| JP3315887B2 (en) | Method for producing carbon-containing refractories | |
| JPH02311361A (en) | Production of aluminum titanate sintered compact stable at high temperature | |
| JPS623072A (en) | Silicon carbide base sintered body and manufacture | |
| JPH0224789B2 (en) | ||
| JPH06279124A (en) | Production of silicon nitride sintered compact | |
| JPH01145380A (en) | Manufacturing method of silicon nitride sintered body | |
| JPS5988374A (en) | Manufacture of silicon nitride ceramics | |
| JP2742620B2 (en) | Boride-aluminum oxide sintered body and method for producing the same | |
| JPH04342468A (en) | Refractory for continuous casting and its production | |
| JPH0437653A (en) | Production of ceramics sintered body | |
| JPH0456791B2 (en) | ||
| JPS62128968A (en) | Nitroxide ceramic material and manufacture | |
| Nunn et al. | Silicon nitride containing rare earth silicate intergranular phases | |
| JP2720201B2 (en) | Method for producing silicon nitride sintered body | |
| JP2961389B2 (en) | High strength magnesia sintered body and method for producing the same | |
| KR920006112B1 (en) | Making method for high p carbide si sintering parts | |
| JPH0517210A (en) | Production of alumina-based composite sintered body and the sintered body |