JPH0422864B2 - - Google Patents
Info
- Publication number
- JPH0422864B2 JPH0422864B2 JP60251144A JP25114485A JPH0422864B2 JP H0422864 B2 JPH0422864 B2 JP H0422864B2 JP 60251144 A JP60251144 A JP 60251144A JP 25114485 A JP25114485 A JP 25114485A JP H0422864 B2 JPH0422864 B2 JP H0422864B2
- Authority
- JP
- Japan
- Prior art keywords
- zro
- temperature
- sintering
- raw material
- ceramic
- 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
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims description 17
- 238000005245 sintering Methods 0.000 claims description 16
- 239000002994 raw material Substances 0.000 claims description 15
- 238000001354 calcination Methods 0.000 claims description 14
- 239000000843 powder Substances 0.000 claims description 14
- 238000001513 hot isostatic pressing Methods 0.000 claims description 11
- 239000000919 ceramic Substances 0.000 claims description 10
- 239000000203 mixture Substances 0.000 claims description 10
- 150000004703 alkoxides Chemical class 0.000 claims description 8
- 229910010293 ceramic material Inorganic materials 0.000 claims description 6
- 238000000465 moulding Methods 0.000 claims description 5
- 238000005467 ceramic manufacturing process Methods 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 239000012535 impurity Substances 0.000 claims description 3
- 230000003301 hydrolyzing effect Effects 0.000 claims description 2
- 229910052751 metal Inorganic materials 0.000 claims description 2
- 239000002184 metal Substances 0.000 claims description 2
- 239000011259 mixed solution Substances 0.000 claims description 2
- 239000000463 material Substances 0.000 description 21
- 238000005520 cutting process Methods 0.000 description 14
- 239000002245 particle Substances 0.000 description 13
- 238000000034 method Methods 0.000 description 11
- 230000000694 effects Effects 0.000 description 5
- 230000007062 hydrolysis Effects 0.000 description 5
- 238000006460 hydrolysis reaction Methods 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 238000003801 milling Methods 0.000 description 4
- 235000013339 cereals Nutrition 0.000 description 3
- 239000006185 dispersion Substances 0.000 description 3
- 239000011159 matrix material Substances 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 238000005452 bending Methods 0.000 description 2
- 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 description 2
- 238000010304 firing Methods 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 238000005728 strengthening Methods 0.000 description 2
- 229910002706 AlOOH Inorganic materials 0.000 description 1
- FIPWRIJSWJWJAI-UHFFFAOYSA-N Butyl carbitol 6-propylpiperonyl ether Chemical compound C1=C(CCC)C(COCCOCCOCCCC)=CC2=C1OCO2 FIPWRIJSWJWJAI-UHFFFAOYSA-N 0.000 description 1
- 240000007594 Oryza sativa Species 0.000 description 1
- 235000007164 Oryza sativa Nutrition 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- SMZOGRDCAXLAAR-UHFFFAOYSA-N aluminium isopropoxide Chemical compound [Al+3].CC(C)[O-].CC(C)[O-].CC(C)[O-] SMZOGRDCAXLAAR-UHFFFAOYSA-N 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- BSDOQSMQCZQLDV-UHFFFAOYSA-N butan-1-olate;zirconium(4+) Chemical compound [Zr+4].CCCC[O-].CCCC[O-].CCCC[O-].CCCC[O-] BSDOQSMQCZQLDV-UHFFFAOYSA-N 0.000 description 1
- 238000009770 conventional sintering Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 239000010730 cutting oil Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000000280 densification Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 238000007731 hot pressing Methods 0.000 description 1
- 238000007373 indentation Methods 0.000 description 1
- 238000003475 lamination Methods 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 239000012188 paraffin wax Substances 0.000 description 1
- 229960005235 piperonyl butoxide Drugs 0.000 description 1
- 238000013001 point bending Methods 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 235000009566 rice Nutrition 0.000 description 1
- 239000011163 secondary particle Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- 238000007514 turning Methods 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Landscapes
- Compositions Of Oxide Ceramics (AREA)
Description
(産業上の利用分野)
本発明は強靭セラミツクス材料、例えばエンジ
ニアリングセラミツクス分野、特に耐摩耗、耐欠
損性にすぐれ重切削及びフライスのような断続切
削用チツプ等の切削工具材料に用いて好適なセラ
ミツクス材料の製造方法に関するものである。
(従来の技術)
加工工具、特に切削工具の分野では焼結技術の
向上によつて従来用いることができなかつた種々
の物質が活用できるようになり、セラミツクス工
具が近年、注目されている。
セラミツクス工具は大別すると、純アルミナセ
ラミツクス(Al2O399%以上)とTiC添加セラミ
ツクス(TiC20〜40W%)の2種類であり、この
うち、前者の純アルミナセラミツクスは大量生産
ができること、耐摩耗性が高いことが長所である
反面、靭性に乏しい欠点があり、主として仕上連
続旋削に用いられている。
一方、これに対しAl2O3焼結体中TiC微粒子を
分散された後者のセラミツクスは、純Al2O3に比
べて靭性、強度にすぐれ、特にフライス加工のよ
うな断続切削工具材料として利用されている。
又、近時、Al2O3にZrO2を分散させた材料が同
様にAl2O3の機械的特性を改善させるものとして
公知であり、その利用が試みられている。
(発明が解決しようとする問題点)
ところで、Al2O3−ZrO2(Y2O3)のような分散
強化型材料の作製上、必要なことは分散粒子を微
細化すること、Al2O3マトリツクス中に均一に分
散させることであるが、従来においてはかかる粒
子の分散は主として原料酸化物粒子の機械的混合
によるものであり、分散粒子は必ずしも均質に分
散しているものとは言えなかつた。
本発明はかかる実状に鑑み、ZrO2粒子を理想
的に微細化し、かつこれをマトリツクス中に均一
に分散させる方法を提供するものである。
(問題点を解決するための手段)
即ち、本発明の特徴とするところは、原料とし
てAl及びZrのアルコキシドを用い、溶液中で原
子レベルで完全に均質混合状態を作り、これを加
水分解することによりAl2O3−ZrO2の完全均質混
合原料を得ることであり、かつ、これを用い仮焼
処理を行うことにより焼結用原料粉末とし、以後
は通常のセラミツクス製造プロセスにより成形焼
成して最終の強靭セラミツクス焼結体とすること
にある。
これをより具体的に説明すると、金属アルコキ
シドの均一混合溶液を加水分解によつてAl2O3
と、ZrO2と、Y2O3,MgO及びCaOからなる群か
ら選ばれた少なくとも1つとを含む混合物を得
て、この得られたZrO25〜30Vol%と、Y2O3,
MgO,CaOから選ばれた1種以上を前記ZrO2に
対して5mol%以下と、残部がAl2O3及び不可避不
純物とから構成される組成の共沈澱物を作り、こ
れを900〜1300℃で仮焼してセラミツクス原料粉
末を得、これを通常のセラミツクス製造過程に従
つて成形後、1400〜1650℃で普通焼結又は/及び
高圧焼結することからなる方法である。
以下、更にこれを順次詳述する。
先ず、本発明は原料としてAl(i−OC3H7)3
(アルミニウムイソプロポキシド)および
(OC4H9)4(ジルコニウムブトキシド)、Y
(OC4H9)3(イツトリウムブトキシド)をエタノー
ル中に所定量溶解させる。
この場合、原料に用いたアルコキシドは例えば
Al(i−OC3H7)3以外のAl(OC4H9)3でもよく、
要は要倍に完全に溶解し加水分解できるものであ
れば可能であるが、通常はAl(i−OC3H7)3,Zr
(OC4H9)3が一般的であつて入手し易いので使用
される。
そして、上記の如く溶解させた溶液を、次いで
撹拌しながら水を滴下し、加水分解を行い、
ZrO25〜30Vol%と、Y2O3,MgO,CaOから選
ばれた1種以上ここではY2O3を前記ZrO2に対し
tmol%以下と残部がAl2O3及び不可避的不純物か
らなる組成の沈澱物を作る。このときZrO2の量
を5〜30Vol%としたのは5%未満ではAl2O3マ
トリツクス粒子の粒界点をすべて満たすことが出
来ず、Al2O3の粒成長を抑制できないため焼結中
にAl2O3の異常粒成長が発生した組成が不均一に
なつて機械的強度を低下させ、一方30%以上にな
るとZrO2の特性が顕在化し硬度の低下が著しく
耐摩耗性が悪くなるからである。
又、Y2O3,MgO,CaOの一種以上をZrO2に対
して5mol%以下を添加するのは、焼結体中の分
散ZrO2粒子を正方晶の状態で安定又は準安定状
態にさせておくためである。
正方晶Zr粒子はクラツク先端で単斜晶に相転
移し、破壊圧力を吸収することによりクラツクの
伝播を阻止する転移強化効果を有する。
しかし、Y2O3等を5mol%以上にすると、立方
晶ZrO2として完全安定化する割合が増し、上記
転移強化の効果がなくなるため靭性、強度の増加
が著しくなる。
従つて、Y2O3等は5mol%以下に止めることが
好ましい。
ところで、加水分解はそのままでは数10Åの非
常に微細粒であり、嵩密度が低く、形成困難であ
る。このため引き続き適当な温度で仮焼処理を行
うことが可能である。勿論、仮焼処理には外に
Al(OC3H7)加水分解生成物はAlOOHのような
水を含んだ状態になつているのでこれを脱水する
という意味もある。
そこで、前記得られた沈澱物をろ過し乾燥した
後、仮焼処理を行い焼結用原料粉末とする。
この場合、仮焼温度として900〜1300℃の範囲
が適用される。
これは例えば仮焼温度と比表面積値の関係は第
1図の通りであり、Al2O3−20%ZrO2(Y2O3)の
900〜1300℃、1hrの仮焼時に65m2/g〜15m2/g
の比表面積値となり、後の成形操作に使える状態
の原料粉末が得られることにより推測される。
なお、900℃以下ではBET値が大きく(粒径
小)成形困難であり、一方、1300℃を越えると粒
子同同志の結晶が顕著となり、仮焼後の解砕が困
難となる。
従つて、900〜1300℃が好ましく、更には1100
〜1300℃が好ましい。
かくして、叙上のようにして得た粉末を以後、
通常のセラミツクス製造プロセスによりバインダ
−添加、成形、焼成を経て最終焼結体に形成する
が、焼成に際しては普通焼結、普通焼結と熱間静
水圧プレス(HIP)の併用、ホツトプレス等、既
知の各手段の単独又は併用が適宜採用可能であ
る。
第2図にかかる焼結時における焼結温度と密度
の関係を示す。
同図においてその焼結体組成は、
Al2O3−20%ZrO2(3mol%Y2O3)であり、焼結
時間は2時間、そしてHIP条件は1450℃で
150MPa,1hrである。
図より明らかなように普通焼結の場合(図中の
白丸)は1400℃以上で92%TDとなり、実用に耐
えるのが好ましくは97%以上の密度が得られる
1450℃以上が必要である。
一方、HIP処理により99%以上に緻密化するた
めにはHIP以前の焼結で95%以上になつているこ
とが好ましく、焼結温度1425℃以上の焼成体を
HIP用とする。
そのため、原料粉末当成形体を1450〜1650℃未
満で普通焼結した後、該焼結体を直接HIP処理す
ることが有効である。
ここで、焼成温度上限を1650℃未満とするのは
この温度で充分緻密化しており、これ以上の温度
は不要であるのみならず、粒成長による機械的特
性の低下を招くからである。
以下、更に具体的な実施例を掲げる。
(実施例)
Al2O3及びZrO2に換算して夫々80Vol%及び
20Vol%のAl(i−OC3H7)3とZr(OC4H9)4、更に
ZrO2に体して3mol%のY2O3に相当するY
(OC4H9)3を三つ口フラスコ中にてエタノールを
溶媒としてアルコキシドの濃度で20WT%を溶解
した。次いでスターラーで上記溶液を撹拌しなが
ら蒸留水を滴下し、アルコキシドを加水分解し
た。
得られた加水分解生成物は比表面積値で100
m2/gの非常に微細で嵩密度の低い粉枠であつ
た。
この粉枠を引き続き大気炉で1200℃、1hrで仮
焼処理し比表面積値30m2/gの原料粉末を得た。
(第1図参照)
上記原料粉末にパラフインワツクスを混合後、
サイズ50×50×8tに1000Kg/cm2で金型成形した。
この成形体の嵩密度は45%であつた。
かくして、上記得られた成形体を更に大気中、
1500℃、2hr焼成したところ、焼成後の焼結体密
度は98.5%であり、抗折強度(3点曲げ)は第3
図より90Kg/Kg、KIC(ビツカース圧子圧入法)
10MN/m3/2、ビツカース硬度(Hv)1680Kg/
mm2と従来材に比べて優れた特性を有していた。
(第2図及び第3図参照)
そこで、上記焼結体を更に1450℃、15MPa,
1hrの条件でHIP処理したところ、第2図、第3
図の各黒丸いで示すように抵抗強度142Kg/mm2,
SIC12MN/m3/2、ビツカース硬度(Hv)1740
Kg/mm2という従来材に比べ大幅に優れた特性を示
した。
以下、上記実施例を実施例1とし実施例2〜
6、比較例1〜7をまとめて第1表に表記する。
表中、組成のその他はZrO2比mol%であり、
HIP処理条件は1450℃、150MPa,1hr、ホツト
プレスは圧力250Kg/cm2,1hrである。
(Field of Industrial Application) The present invention is a tough ceramic material, for example, a ceramic material in the field of engineering ceramics, which has excellent wear resistance and chipping resistance, and is suitable for use in cutting tool materials such as tips for heavy cutting and interrupted cutting such as milling cutters. This invention relates to a method for manufacturing materials. (Prior Art) In the field of processing tools, especially cutting tools, improvements in sintering technology have made it possible to utilize various materials that could not be used in the past, and ceramic tools have been attracting attention in recent years. Ceramic tools can be roughly divided into two types: pure alumina ceramics (99% Al 2 O 3 or more) and TiC-added ceramics (TiC 20 to 40W%). Of these, the former pure alumina ceramics can be mass-produced and has excellent durability. Although its advantage is high abrasion resistance, it has the disadvantage of poor toughness, so it is mainly used for finish continuous turning. On the other hand, the latter ceramics, which are made by dispersing TiC particles in an Al 2 O 3 sintered body, have superior toughness and strength compared to pure Al 2 O 3 , and are particularly useful as materials for interrupted cutting tools such as milling. has been done. Moreover, recently, a material in which ZrO 2 is dispersed in Al 2 O 3 is known as a material that similarly improves the mechanical properties of Al 2 O 3 , and attempts have been made to utilize this material. (Problems to be Solved by the Invention) By the way, in producing a dispersion-strengthened material such as Al 2 O 3 −ZrO 2 (Y 2 O 3 ), what is necessary is to make the dispersed particles finer, and to make the dispersed particles finer. The goal is to uniformly disperse the particles in the O 3 matrix, but in the past, the dispersion of such particles was mainly due to mechanical mixing of the raw material oxide particles, and although the dispersed particles were not necessarily homogeneously dispersed, Nakatsuta. In view of this situation, the present invention provides a method for ideally making ZrO 2 particles fine and uniformly dispersing them in a matrix. (Means for Solving the Problems) That is, the present invention is characterized by using Al and Zr alkoxides as raw materials, creating a completely homogeneous mixed state at the atomic level in a solution, and then hydrolyzing this. By doing this, a completely homogeneous mixed raw material of Al 2 O 3 -ZrO 2 is obtained, and by performing a calcination treatment using this, it is made into a raw material powder for sintering, which is then shaped and fired using a normal ceramic manufacturing process. The purpose is to produce a final tough ceramic sintered body. To explain this more specifically, a homogeneous mixed solution of metal alkoxides is hydrolyzed to form Al 2 O 3
, ZrO 2 , and at least one selected from the group consisting of Y 2 O 3 , MgO, and CaO.
A coprecipitate having a composition of 5 mol% or less of one or more selected from MgO and CaO based on the ZrO 2 and the balance consisting of Al 2 O 3 and unavoidable impurities is prepared, and this is heated at 900 to 1300°C. This method consists of calcination to obtain a ceramic raw material powder, which is molded according to a normal ceramic manufacturing process, and then normal sintered and/or high pressure sintered at 1400 to 1650°C. This will be further explained in detail below. First, the present invention uses Al(i-OC 3 H 7 ) 3 as a raw material.
(aluminum isopropoxide) and (OC 4 H 9 ) 4 (zirconium butoxide), Y
A predetermined amount of (OC 4 H 9 ) 3 (yztrium butoxide) is dissolved in ethanol. In this case, the alkoxide used as the raw material is, for example,
Al(OC 4 H 9 ) 3 other than Al(i-OC 3 H 7 ) 3 may be used,
In short, it is possible as long as it can be completely dissolved and hydrolyzed, but usually Al(i-OC 3 H 7 ) 3 , Zr
(OC 4 H 9 ) 3 is used because it is common and easily available. Then, water was added dropwise to the solution dissolved as above while stirring to perform hydrolysis.
ZrO 2 5 to 30 Vol% and one or more selected from Y 2 O 3 , MgO, CaO Here, Y 2 O 3 is added to the ZrO 2
A precipitate having a composition of less than tmol% and the remainder consisting of Al 2 O 3 and inevitable impurities is produced. At this time, the amount of ZrO 2 was set to 5 to 30 Vol% because if it was less than 5%, it would not be possible to fill all the grain boundary points of the Al 2 O 3 matrix particles and the grain growth of Al 2 O 3 could not be suppressed. Abnormal grain growth of Al 2 O 3 occurs in the composition, which makes it non-uniform and reduces mechanical strength.On the other hand, when it exceeds 30%, the characteristics of ZrO 2 become apparent and the hardness decreases significantly, resulting in poor wear resistance. Because it will be. Furthermore, adding 5 mol% or less of one or more of Y 2 O 3 , MgO, and CaO to ZrO 2 makes the dispersed ZrO 2 particles in the sintered body stable or metastable in the tetragonal state. This is to keep it safe. Tetragonal Zr particles undergo a phase transition to monoclinic crystal at the tip of the crack, and have a transition-strengthening effect that prevents crack propagation by absorbing fracture pressure. However, when Y 2 O 3 or the like is increased to 5 mol % or more, the proportion of complete stabilization as cubic ZrO 2 increases, and the above-mentioned dislocation strengthening effect disappears, resulting in a significant increase in toughness and strength. Therefore, it is preferable to limit Y 2 O 3 etc. to 5 mol % or less. By the way, hydrolysis produces very fine particles of several tens of angstroms in size, which have a low bulk density and are difficult to form. For this reason, it is possible to subsequently perform the calcination treatment at an appropriate temperature. Of course, the outside is used for the calcination process.
Since the Al (OC 3 H 7 ) hydrolysis product is in a water-containing state like AlOOH, it also means dehydrating it. Therefore, the obtained precipitate is filtered and dried, and then subjected to a calcining treatment to obtain a raw material powder for sintering. In this case, a range of 900 to 1300°C is applied as the calcination temperature. For example, the relationship between the calcination temperature and the specific surface area value is shown in Figure 1 .
65m 2 /g - 15m 2 /g when calcined for 1 hour at 900 - 1300℃
This is estimated based on the fact that the raw material powder is ready for use in subsequent molding operations. Note that below 900°C, the BET value is large (particle size is small) and forming is difficult; on the other hand, when the temperature exceeds 1300°C, crystallization of particles becomes noticeable, making it difficult to crush after calcination. Therefore, the temperature is preferably 900 to 1300°C, more preferably 1100°C.
~1300°C is preferred. Henceforth, the powder obtained as described above,
The final sintered body is formed through the addition of a binder, molding, and sintering using the usual ceramic manufacturing process, but the sintering process can be performed using conventional sintering, a combination of sintering and hot isostatic pressing (HIP), hot pressing, etc. Each of the above means can be used alone or in combination as appropriate. FIG. 2 shows the relationship between sintering temperature and density during sintering. In the figure, the composition of the sintered body is Al2O3-20 % ZrO2 ( 3mol % Y2O3 ), the sintering time is 2 hours, and the HIP condition is 1450℃.
150MPa, 1hr. As is clear from the figure, in the case of normal sintering (white circles in the figure), the TD is 92% at temperatures above 1400℃, and a density of 97% or higher is preferably obtained for practical use.
A temperature of 1450℃ or higher is required. On the other hand, in order to achieve densification of 99% or more by HIP treatment, it is preferable that the sintering before HIP achieves 95% or more, and the sintered body should be sintered at a temperature of 1425℃ or higher.
For HIP use. Therefore, it is effective to normally sinter the molded body of the raw material powder at a temperature below 1450 to 1650°C, and then directly subject the sintered body to HIP treatment. Here, the upper limit of the firing temperature is set to less than 1650°C because the material is sufficiently densified at this temperature, and a temperature higher than this is not only unnecessary, but also causes deterioration of mechanical properties due to grain growth. More specific examples are listed below. (Example) 80Vol% and 80Vol% respectively in terms of Al 2 O 3 and ZrO 2
20Vol% Al(i- OC3H7 ) 3 and Zr ( OC4H9 ) 4 , and
Y corresponding to 3 mol% Y 2 O 3 based on ZrO 2
(OC 4 H 9 ) 3 was dissolved at an alkoxide concentration of 20WT% in a three-necked flask using ethanol as a solvent. Distilled water was then added dropwise to the solution while stirring it with a stirrer to hydrolyze the alkoxide. The obtained hydrolysis product has a specific surface area of 100
The powder frame was extremely fine and had a low bulk density of m 2 /g. This powder frame was then calcined in an air furnace at 1200°C for 1 hour to obtain a raw material powder with a specific surface area of 30 m 2 /g.
(See Figure 1) After mixing paraffin wax with the above raw material powder,
It was molded into a mold with a size of 50 x 50 x 8 tons at 1000 kg/cm 2 .
The bulk density of this molded body was 45%. In this way, the molded product obtained above is further exposed to the atmosphere.
When fired at 1500℃ for 2 hours, the density of the sintered body after firing was 98.5%, and the bending strength (3-point bending) was 3rd grade.
From the diagram, 90Kg/Kg, KIC (Bitzkers indentation method)
10MN/m 3/2 , Bitkers hardness (Hv) 1680Kg/
mm 2 and had superior properties compared to conventional materials.
(See Figures 2 and 3) Therefore, the above sintered body was further heated at 1450℃ and 15MPa.
After HIP treatment for 1 hour, Figures 2 and 3
As shown by each black circle in the figure, the resistance strength is 142Kg/mm 2 ,
SIC12MN/m 3/2 , Bitkers hardness (Hv) 1740
Kg/mm 2 , which showed significantly superior properties compared to conventional materials. Hereinafter, the above example will be referred to as Example 1, and Examples 2 to 2 will be described as Example 1.
6. Comparative Examples 1 to 7 are summarized in Table 1. In the table, the other compositions are ZrO 2 mol%,
The HIP treatment conditions are 1450° C., 150 MPa, 1 hr, and the hot press pressure is 250 Kg/cm 2 , 1 hr.
【表】
なお、上表において、比較例1は実施例1と同
様にして得た加水分解生成物を用い、仮焼温度を
900℃とした場合で、BET比表面積値は60m2/g
である。(第1図参照)
これは金型プレス成形1000Kg/cm2でラミネーシ
ヨンを越して成形できなかつた。
500Kg/cm2に圧力を下げたところ、成形するこ
とはできたが嵩高密度は32%であり、この成形体
は1650℃までで95%以上に焼結しなかつた。
又、比較例2に見られる如く仮焼温度850℃で
は粉体の圧縮性が極めて悪く成形不可能であつ
た。
一方、1350℃で仮焼処理した比較例3では粉体
間の焼結が起こり、2次粒子の解枠が困難であつ
た。
このため、焼結体中に大きな欠陥(ボア)が残
留し易く、従つて強度は62Kg/cm2と比較的低く、
分散強化の効果は殆ど認められない。またHIP処
理によつても大径ポアは除去できず、強度改善も
望めない。
次に上記各実施例における試料焼結体を抽出し
シリンダーブロツク上面のフライス加工用の切削
工具に用いた使用例を第2表に掲げる。
被削材;シリンダーブロツク上面(200×500)材
料……FC−25
切削速度 V=500m/min
切込み t0.5mm
送 り f=0.15mm/t
工 具 SNGNTST(15.875×15.875×6.35mm、
コーナーR2.0mm 切れ刃チヤンフアー0.13mm×
20
なお、表中、試料No.は第1表における試料No.を
示す。[Table] In the above table, Comparative Example 1 uses a hydrolysis product obtained in the same manner as Example 1, and the calcination temperature is
At 900℃, the BET specific surface area value is 60m 2 /g
It is. (See Figure 1) This could not be molded beyond the lamination when press molded with a mold of 1000 kg/cm 2 . When the pressure was lowered to 500 Kg/cm 2 , molding was possible, but the bulk density was 32%, and this molded product was not sintered to more than 95% at temperatures up to 1650°C. Further, as seen in Comparative Example 2, at a calcination temperature of 850°C, the compressibility of the powder was extremely poor and molding was impossible. On the other hand, in Comparative Example 3, which was calcined at 1350°C, sintering occurred between the powders, making it difficult to break up the secondary particles. For this reason, large defects (bores) tend to remain in the sintered body, and the strength is relatively low at 62 kg/cm 2 .
Almost no effect of dispersion reinforcement was observed. Moreover, even with HIP treatment, large diameter pores cannot be removed and no improvement in strength can be expected. Next, Table 2 lists examples of use in which sample sintered bodies in each of the above examples were extracted and used as a cutting tool for milling the upper surface of a cylinder block. Work material: Cylinder block top surface (200 x 500) Material: FC-25 Cutting speed V = 500 m/min Depth of cut t0.5 mm Feed f = 0.15 mm/t Tool SNGNTST (15.875 x 15.875 x 6.35 mm,
Corner R2.0mm Cutting edge chamfer 0.13mm×
20 In the table, the sample number indicates the sample number in Table 1.
【表】
上記表より分かる如く、本発明方法による材料
1a,3a,4aは他のものに比べ強靭性をもつ
た耐欠損性にすぐれ、フライス加工のような断続
切削用工具材として最適である。
(発明の効果)
以上の如く本発明方法によればアルコキシド法
によりAl2O3とZrO2の理想的な均一分散が達成で
きたため、均一微細組成が得られ、その結果、従
来のセラミツクス材料に比較して著しく高密度か
つ高靭性の材料を得ることができると共に、仮焼
処理の最適化により従来、取扱いに難があるとさ
れていたアルコキシド加水分解原料の形成を容易
となし、しかも近時、高速加工化と共にその性能
向上が求められていた切削工具に本材料を使用
し、かつライス加工のような断続切削やNC加工
で切削油を用いなければならない場合においても
すぐれた切削性能(耐欠損性)が認められ、重切
削及い断続切削用チツプ材等として本発明方法は
この材料特性の改善、該材料の応用の拡大に顕著
な効用が期待される。[Table] As can be seen from the above table, materials 1a, 3a, and 4a produced by the method of the present invention have superior toughness and fracture resistance compared to other materials, and are optimal as tool materials for interrupted cutting such as milling. . (Effects of the Invention) As described above, according to the method of the present invention, ideal uniform dispersion of Al 2 O 3 and ZrO 2 was achieved by the alkoxide method, so a uniform fine composition was obtained, and as a result, it was superior to conventional ceramic materials. In addition to being able to obtain a material with significantly higher density and toughness compared to other materials, the optimization of the calcination process facilitates the formation of alkoxide hydrolyzed raw materials, which were previously thought to be difficult to handle. This material was used in cutting tools that were required to improve performance along with high-speed machining, and it also provided excellent cutting performance (durability) even when cutting oil was required in interrupted cutting such as rice processing and NC processing. The method of the present invention is expected to have remarkable effects on improving the properties of this material and expanding its applications as a chip material for heavy cutting and interrupted cutting.
第1図は比表面積値に及ぼす仮焼温度の影響を
表す図表、第2図は焼結温度に対する焼結体密度
の関係を示す図表、第3図は普通焼結体(白丸)
及びHIP処理(黒丸)の焼結温度に対する抗折強
度を示す図表である。
Figure 1 is a chart showing the influence of calcination temperature on the specific surface area value, Figure 2 is a chart showing the relationship between sintered compact density and sintering temperature, and Figure 3 is a chart showing normal sintered compact (white circles).
It is a chart showing the bending strength against the sintering temperature of the HIP treatment (black circles).
Claims (1)
することによつてAl2O3と、ZrO2と、Y2O3,
MgO及びCaOからなる群から選択された少なく
とも1つとを含む混合物を得て、この得られた混
合物の組成がZrO25〜30Vol%と、前記群から選
択された成分をZrO2に対して5mol%以下と残部
がAl2O3及び不可避不純物から構成されており、
しかも、この混合物を900〜1300℃で仮焼して得
たセラミツクス原料粉末を用い、これを通常のセ
ラミツクス製造過程に従つて成形した後、1400〜
1650℃未満で普通焼結又は/及び加圧焼結せしめ
ることを特徴とする強靭セラミツク材料の製造方
法。 2 仮焼温度が1100〜1300℃である特許請求の範
囲第1項記載の強靭セラミツク材料の製造方法。 3 原料粉末形成体を1450〜1650℃未満で普通焼
結した後、該焼結体を引き続き直接熱間静水圧加
圧処理する特許請求の範囲第1項又は第2項記載
の強靭セラミツク材料の製造方法。[Claims] 1. By hydrolyzing a homogeneous mixed solution of metal alkoxides, Al 2 O 3 , ZrO 2 , Y 2 O 3 ,
A mixture containing at least one selected from the group consisting of MgO and CaO is obtained, and the composition of the obtained mixture is 5 to 30 Vol% of ZrO 2 and 5 mol of the component selected from the group relative to ZrO 2. % or less and the remainder consists of Al 2 O 3 and inevitable impurities,
Moreover, using the ceramic raw material powder obtained by calcining this mixture at 900 to 1300°C, and molding it according to the normal ceramic manufacturing process,
A method for producing a tough ceramic material, characterized by normal sintering and/or pressure sintering at a temperature below 1650°C. 2. The method for producing a tough ceramic material according to claim 1, wherein the calcination temperature is 1100 to 1300°C. 3. The tough ceramic material according to claim 1 or 2, wherein the raw material powder formed body is normally sintered at a temperature of 1450 to less than 1650°C, and then the sintered body is directly subjected to hot isostatic pressing. Production method.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP60251144A JPS62108765A (en) | 1985-11-08 | 1985-11-08 | Manufacture of tough ceramic material |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP60251144A JPS62108765A (en) | 1985-11-08 | 1985-11-08 | Manufacture of tough ceramic material |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS62108765A JPS62108765A (en) | 1987-05-20 |
JPH0422864B2 true JPH0422864B2 (en) | 1992-04-20 |
Family
ID=17218325
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP60251144A Granted JPS62108765A (en) | 1985-11-08 | 1985-11-08 | Manufacture of tough ceramic material |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS62108765A (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2511700B2 (en) * | 1988-08-22 | 1996-07-03 | 東芝タンガロイ株式会社 | Ceramics sintered body for cutting tools |
JPH03112854A (en) * | 1989-09-25 | 1991-05-14 | Osaka Cement Co Ltd | Production of high strength alumina-zirconia system ceramic |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5614473A (en) * | 1979-07-17 | 1981-02-12 | Ngk Spark Plug Co | Ceramic sintered body for cutting tool |
JPS57175724A (en) * | 1981-04-23 | 1982-10-28 | Ngk Insulators Ltd | Preparation of high purity ceramic powder |
JPS5924751A (en) * | 1982-08-02 | 1984-02-08 | Toray Ind Inc | Polyamide resin composition |
JPS60161371A (en) * | 1984-02-01 | 1985-08-23 | 工業技術院長 | Manufacture of high strength ceramic sintered body |
-
1985
- 1985-11-08 JP JP60251144A patent/JPS62108765A/en active Granted
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5614473A (en) * | 1979-07-17 | 1981-02-12 | Ngk Spark Plug Co | Ceramic sintered body for cutting tool |
JPS57175724A (en) * | 1981-04-23 | 1982-10-28 | Ngk Insulators Ltd | Preparation of high purity ceramic powder |
JPS5924751A (en) * | 1982-08-02 | 1984-02-08 | Toray Ind Inc | Polyamide resin composition |
JPS60161371A (en) * | 1984-02-01 | 1985-08-23 | 工業技術院長 | Manufacture of high strength ceramic sintered body |
Also Published As
Publication number | Publication date |
---|---|
JPS62108765A (en) | 1987-05-20 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5114891A (en) | Sintered material based on aluminum oxide | |
KR910005053B1 (en) | High toughness zro2 sintered body and method of producing the same | |
KR20070065353A (en) | A zirconia ceramic | |
CN113563074B (en) | Two-phase calcium tantalate ceramic and preparation method thereof | |
JPS6140621B2 (en) | ||
JP2001521874A (en) | Platelet reinforced sintered compact | |
US4678761A (en) | Sinterable and strengthened magnesium oxide ceramic materials | |
US3929498A (en) | Sintered zirconia bodies | |
JPH0553751B2 (en) | ||
JPH0422864B2 (en) | ||
JPH0137348B2 (en) | ||
JPS6259565A (en) | High density alumina/zirconia sintered body and its production | |
JP3076682B2 (en) | Alumina-based sintered body and method for producing the same | |
JPH04209761A (en) | Zirconia porcelain and its production | |
JPH02180747A (en) | Wear resistant alumina ceramics and production thereof | |
EP0467539B1 (en) | Process for forming ceramics | |
JP2650049B2 (en) | Ceramic cutting tool and its manufacturing method | |
CN107129296A (en) | A kind of doping vario-property yellow zirconium oxide ceramic and its production method of wire-drawing wheel for wire-drawing wheel | |
JPS62275067A (en) | Manufacture of silicon nitride sintered body | |
JPH0687650A (en) | Alumina-based sintered compact and its production | |
JPH03146454A (en) | Production of fine powder of ceramics and refractories | |
JPH052622B2 (en) | ||
JPS6337075B2 (en) | ||
CN116514543A (en) | Zirconia composite ceramic | |
JPH04160053A (en) | Wear-resistant alumina-zirconia sintered body and its production |