JPS63139071A - Ceramic body joining method - Google Patents
Ceramic body joining methodInfo
- Publication number
- JPS63139071A JPS63139071A JP28614086A JP28614086A JPS63139071A JP S63139071 A JPS63139071 A JP S63139071A JP 28614086 A JP28614086 A JP 28614086A JP 28614086 A JP28614086 A JP 28614086A JP S63139071 A JPS63139071 A JP S63139071A
- Authority
- JP
- Japan
- Prior art keywords
- bonding
- weight
- ceramic bodies
- joining
- turbine impeller
- 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.)
- Granted
Links
- 239000000919 ceramic Substances 0.000 title claims description 41
- 238000000034 method Methods 0.000 title claims description 32
- 238000005304 joining Methods 0.000 title claims description 25
- 239000002245 particle Substances 0.000 claims description 39
- 239000000463 material Substances 0.000 claims description 38
- 239000011148 porous material Substances 0.000 claims description 24
- 238000005245 sintering Methods 0.000 claims description 24
- 238000000465 moulding Methods 0.000 claims description 7
- 238000002844 melting Methods 0.000 claims description 4
- 230000008018 melting Effects 0.000 claims description 4
- 238000005219 brazing Methods 0.000 description 18
- 239000000843 powder Substances 0.000 description 16
- 230000000694 effects Effects 0.000 description 14
- 239000000945 filler Substances 0.000 description 13
- 229910052751 metal Inorganic materials 0.000 description 13
- 239000002184 metal Substances 0.000 description 13
- 239000002994 raw material Substances 0.000 description 13
- 239000002253 acid Substances 0.000 description 11
- 238000005452 bending Methods 0.000 description 9
- 239000013078 crystal Substances 0.000 description 8
- 238000010828 elution Methods 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- 229910018054 Ni-Cu Inorganic materials 0.000 description 5
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 5
- 229910018487 Ni—Cr Inorganic materials 0.000 description 5
- 229910018481 Ni—Cu Inorganic materials 0.000 description 5
- 239000002612 dispersion medium Substances 0.000 description 5
- 238000005470 impregnation Methods 0.000 description 5
- 229910017604 nitric acid Inorganic materials 0.000 description 5
- 238000007569 slipcasting Methods 0.000 description 5
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 238000004873 anchoring Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 230000002159 abnormal effect Effects 0.000 description 3
- 150000007513 acids Chemical class 0.000 description 3
- 238000000280 densification Methods 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 238000013001 point bending Methods 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- 229910010293 ceramic material Inorganic materials 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 229910052681 coesite Inorganic materials 0.000 description 2
- 229910052906 cristobalite Inorganic materials 0.000 description 2
- 239000011261 inert gas Substances 0.000 description 2
- 239000000155 melt Substances 0.000 description 2
- 239000011812 mixed powder Substances 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 238000010298 pulverizing process Methods 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- 235000012239 silicon dioxide Nutrition 0.000 description 2
- 239000006104 solid solution Substances 0.000 description 2
- 229910052682 stishovite Inorganic materials 0.000 description 2
- 229910052905 tridymite Inorganic materials 0.000 description 2
- 239000013585 weight reducing agent Substances 0.000 description 2
- 101100348017 Drosophila melanogaster Nazo gene Proteins 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 230000005856 abnormality Effects 0.000 description 1
- 235000019402 calcium peroxide Nutrition 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 150000004820 halides Chemical class 0.000 description 1
- 238000001746 injection moulding Methods 0.000 description 1
- 239000012633 leachable Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000007740 vapor deposition Methods 0.000 description 1
Landscapes
- Ceramic Products (AREA)
Abstract
(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.
Description
【発明の詳細な説明】
A1発明の目的
(1)産業上の利用分野
本発明はセラミック体の接合方法、特に成形および焼結
工程を経て得られる第1および第2セラミック体を接合
する方法に関する。DETAILED DESCRIPTION OF THE INVENTION A1 Object of the Invention (1) Industrial Application Field The present invention relates to a method for joining ceramic bodies, particularly to a method for joining first and second ceramic bodies obtained through a molding and sintering process. .
(2)従来の技術
従来、この種接合方法として、両セラミック体の接合面
間に存する金属性接合材を熔融してそれらを接合する手
法が知られている(特開昭60−260479号公報参
照)。(2) Prior Art Conventionally, as a joining method of this type, a method is known in which a metallic joining material existing between the joining surfaces of both ceramic bodies is melted to join them (Japanese Patent Laid-Open No. 60-260479). reference).
(3)発明が解決しようとする問題点
しかしながら、前記方法は両セラミック体の接合面に対
する接合材の濡れ性および両接合面と接合材との化学反
応による結合を狙ったもので、あくまでも両接合面上に
おける接合材の接合効果を期待するものであるから、高
温下等、苛酷な状況下においては接合強度が不十分であ
るといった問題がある。(3) Problems to be Solved by the Invention However, the above-mentioned method aims at the wettability of the bonding material to the bonding surfaces of both ceramic bodies and the bonding through a chemical reaction between both bonding surfaces and the bonding material. Since the bonding effect of the bonding material on the surface is expected, there is a problem that the bonding strength is insufficient under harsh conditions such as high temperatures.
本発明は前記に鑑み、両セラミック体の接合面上におけ
る接合材の接合効果だけでなく、両接合面よりも内部に
対する接合材のアンカ効果を得、これにより両セラミッ
ク体の接合強度を大幅に向上させることのできる前記接
合方法を提供することを目的とする。In view of the above, the present invention provides not only the bonding effect of the bonding material on the bonding surfaces of both ceramic bodies, but also the anchoring effect of the bonding material on the inside of both the bonding surfaces, thereby significantly increasing the bonding strength of both ceramic bodies. It is an object of the present invention to provide the above-mentioned joining method that can be improved.
B6発明の構成
fll 問題点を解決するための手段本発明は、成形
および焼結工程を経て得られる第1および第2セラミッ
ク体を接合するに当り、前記第1および第2セラミック
体より、それらの成形に先立って配合された溶出可能粒
子を溶出し、両セラミック体に、それらの接合面に開口
する多数の連続気孔を形成する工程と;前記第1および
第2セラミック体の前記再接合面間に介在させた金属性
接合材を溶融し、該接合材を前記両セラミック体の前記
連続気孔に含浸させる工程と;を用いることを特徴とす
る。B6 Structure of the InventionFll Means for Solving the Problems The present invention provides that when joining the first and second ceramic bodies obtained through the molding and sintering process, the first and second ceramic bodies eluting the blended elutable particles prior to molding to form a large number of continuous pores in both ceramic bodies that open at the bonding surfaces thereof; the re-bonding surfaces of the first and second ceramic bodies; The method is characterized by using a step of melting a metallic bonding material interposed therebetween and impregnating the continuous pores of both the ceramic bodies with the bonding material.
(2)作 用
溶融した接合材は両セラミック体の接合面を儒らすので
、両接合面上における接合材の接合効果を得ることがで
きる。また両セラミック体の連続気孔への接合材の含浸
により接合材のアンカ効果を得ることができる。(2) Function Since the molten bonding material makes the bonding surfaces of both ceramic bodies elastic, the bonding effect of the bonding material on both bonding surfaces can be obtained. Further, by impregnating the continuous pores of both ceramic bodies with the bonding material, an anchoring effect of the bonding material can be obtained.
これにより、両セラミック体の接合強度を大幅に向上さ
せることができる。Thereby, the bonding strength between both ceramic bodies can be significantly improved.
(3)実施例
第1図(alは第1セラミック体としてのタービン羽根
車1を示し、また同図(blはタービン羽根車lに接合
される第2セラミック体としての回転軸2を示す。(3) Embodiment FIG. 1 (al indicates a turbine impeller 1 as a first ceramic body, and bl indicates a rotating shaft 2 as a second ceramic body joined to the turbine impeller 1.
タービン羽根車1は、小径軸部3を備えた羽根車本体4
と、その小径軸部3の外面全体を覆うように羽根車本体
4と一体化された接合筒部5とよりなる。The turbine impeller 1 includes an impeller body 4 having a small diameter shaft portion 3.
and a joint cylindrical portion 5 that is integrated with the impeller main body 4 so as to cover the entire outer surface of the small diameter shaft portion 3.
回転軸2は、横断面四角形の角筒部6を備えた軸本体7
と、その角筒部6の内面全体を覆うように軸本体7と一
体化された接合筒部8とよりなる。The rotating shaft 2 has a shaft body 7 having a rectangular tube portion 6 with a square cross section.
and a joint cylinder part 8 that is integrated with the shaft body 7 so as to cover the entire inner surface of the square cylinder part 6.
タービン羽根車lおよび回転軸2は、原料の調製、成形
および焼結の各工程を経て製造される。The turbine impeller 1 and the rotating shaft 2 are manufactured through the steps of preparing raw materials, molding, and sintering.
原料は、羽根車本体4および軸本体7と再接合筒部5,
8とでは異なり、羽根車本体4および軸本体7の原料と
してはセラミック粉末、その粉末の焼結温度で焼結作用
を発揮する焼結助剤等が用いられ、また再接合筒部5,
8の原料には、前記の外にそれら筒部5.8を連続気孔
を持つ三次元網目構造にするため、酸により溶出し得る
溶出可能粒子が用いられる。The raw material is the impeller main body 4, the shaft main body 7, the rejoining cylinder part 5,
8, the raw materials for the impeller body 4 and the shaft body 7 are ceramic powder, a sintering aid that exhibits a sintering effect at the sintering temperature of the powder, and the rejoining cylindrical portion 5,
In addition to the above, elutable particles that can be eluted with acid are used as the raw material No. 8 in order to form the cylindrical portion 5.8 into a three-dimensional network structure with continuous pores.
セラミック粉末としては、5izN4.5iC1ZrO
□、Tic、TiN等の単独粉末およびこれらから選択
されたものの混合粉末が該当する。As the ceramic powder, 5izN4.5iC1ZrO
This includes individual powders such as □, Tic, and TiN, and mixed powders of materials selected from these.
焼結助剤としては、A It Os 、Yz 03 、
Mgo、SiO□等の単独粉末およびこれらから選択さ
れたものの混合粉末が該当する。As the sintering aid, A It Os , Yz 03 ,
Single powders such as Mgo and SiO□ and mixed powders of materials selected from these are applicable.
溶出可能粒子としては、Alz Os 、NatOlS
i Ox 、Mg OlK、01Bz Os 、Ca
Oおよび必要に応じてCa Cl zを混合、溶融、冷
却固化および微粉砕の各工程を経て製造されたものが8
亥当する。Elutable particles include AlzOs, NatOlS
iOx, MgOlK, 01BzOs, Ca
8 is produced through the steps of mixing O and Ca Cl z as necessary, melting, solidifying by cooling, and pulverizing.
Inferred.
原料の調製に当たっては、前記各種構成物質をボールミ
ル等の混合機を用いて所定時間混合し、それらを均一に
分散させる。In preparing the raw materials, the various constituent substances are mixed for a predetermined time using a mixer such as a ball mill to uniformly disperse them.
前記原料を用いて成形体を得る場合には、加圧成形法、
射出成形法、水を分散媒としたスリップキャスティング
法等が用いられる。When obtaining a molded body using the above-mentioned raw materials, a pressure molding method,
An injection molding method, a slip casting method using water as a dispersion medium, etc. are used.
前記成形体に焼結処理を施す場合の条件は、N2ガス等
の不活性ガス雰囲気中にて1200〜1800℃、0.
5〜24時間である。The conditions for performing the sintering treatment on the molded body are 1200 to 1800° C. and 0.5° C. in an inert gas atmosphere such as N2 gas.
5 to 24 hours.
前記焼結処理によって緻密な組織を有するタービン羽根
車1および回転軸2が得られる。タービン羽根車lおよ
び回転軸2の緻密化の程度は、主として焼結助剤の配合
量ならびに焼結処理における温度および時間によって制
御される。The sintering process provides a turbine impeller 1 and a rotating shaft 2 having a dense structure. The degree of densification of the turbine impeller 1 and the rotating shaft 2 is mainly controlled by the amount of the sintering aid and the temperature and time in the sintering process.
また溶出可能粒子も焼結助剤的な機能をするので、再接
合筒部5,8においては前記粒子の配合量も緻密化に関
与する因子となる。Furthermore, since the elutable particles also function as a sintering aid, the amount of the particles blended in the rejoining cylindrical portions 5 and 8 is also a factor involved in densification.
再接合筒部5,8から溶出可能粒子を溶出するために用
いられる酸としては、硝酸、塩酸等の単−酸、これらの
混酸、前記単一酸または前記混酸に少量のフッ化水素酸
を添加したもの等が用いられる。The acids used to elute the elutable particles from the rejoining cylinder parts 5 and 8 include single acids such as nitric acid and hydrochloric acid, mixed acids thereof, and a small amount of hydrofluoric acid added to the single acid or mixed acid. Those added are used.
多酸により溶出可能粒子を可溶性塩類に変えて再接合筒
部5,8より溶出する。その際、酸を流通させると共に
それに超音波振動を付与し、これにより連続気孔内にお
ける可溶性塩類の沈積を回避し、また溶出反応を促進す
ることができる。The elutable particles are converted into soluble salts by the polyacid and eluted from the rejoining cylinder portions 5 and 8. At this time, the acid is allowed to flow and ultrasonic vibrations are applied thereto, thereby avoiding the deposition of soluble salts in the continuous pores and promoting the elution reaction.
前記溶出処理によって、再接合筒部5.8は連続気孔を
持つ三次元網目構造となるもので、この場合再接合筒部
5.8の強度は、主として連続気孔の大きさく直径)お
よび気孔率により左右される。Through the elution process, the rejoined cylinder part 5.8 becomes a three-dimensional network structure with continuous pores, and in this case, the strength of the rejoined cylinder part 5.8 is mainly determined by the size and diameter of the continuous pores and the porosity. depends on.
第2図は、再接合筒部5,8の気孔率と曲げ強さとの関
係を示し、それらの接合強度を考慮すると、気孔率は1
0〜30%が適当であり、また連続気孔の大きさは1〜
10μmが適当である。このように連続気孔の大きさお
よび気孔率を設定することにより、前記焼結処理におけ
る緻密化に伴うセラミック粉末の結晶成長もあって、再
接合筒部5.8の強度を向上させることができる。Figure 2 shows the relationship between the porosity and bending strength of the rejoined cylindrical parts 5 and 8. Considering their joining strength, the porosity is 1.
0 to 30% is appropriate, and the size of continuous pores is 1 to 30%.
10 μm is appropriate. By setting the size and porosity of the continuous pores in this manner, the strength of the rejoined cylindrical portion 5.8 can be improved due to crystal growth of the ceramic powder accompanying densification in the sintering process. .
前記連続気孔の大きさおよび気孔率は溶出可能粒子の粒
径および配合量によって左右されるものであるから、前
記適当範囲を得ることができるように前記粒径および配
合量が決定される。Since the size of the continuous pores and the porosity depend on the particle size and amount of the elutable particles, the particle size and amount of the elutable particles are determined so as to obtain the appropriate range.
タービン羽根車1と回転軸2とを一体化する場合は、溶
出処理後の再接合筒部5,8を嵌合すると共に接合筒部
5の外面および接合筒部8の内面、したがって再接合面
間に金属性接合材を介在させる。そして、大気下、真空
下等の雰囲気下において角筒部6をその外周から加圧す
ると共に接合材を溶融し、その接合材によって再接合筒
部5,8の接合面を濡らし、またその接合材を再接合筒
部5.8の連続気孔に含浸させるものである。接合材の
溶融は真空下で行う方が、その接合材の酸化を防止し得
るので、接合強度を増す上に有効である。When the turbine impeller 1 and the rotating shaft 2 are integrated, the rejoined cylinder parts 5 and 8 after elution treatment are fitted together, and the outer surface of the joint cylinder part 5 and the inner surface of the joint cylinder part 8, and therefore the rejoined surface. A metallic bonding material is interposed in between. Then, in an atmosphere such as air or vacuum, the rectangular tube part 6 is pressurized from its outer periphery, the bonding material is melted, the bonding material wets the bonding surfaces of the re-bonding tube sections 5 and 8, and the bonding material is impregnated into the continuous pores of the rejoining cylindrical portion 5.8. Melting the bonding material under vacuum can prevent the bonding material from oxidizing, which is more effective in increasing the bonding strength.
また接合材は、蒸着等の手段を用いて予め再接合筒部5
,8の少なくとも一方に保持させておいてもよい。In addition, the bonding material is applied to the re-bonded cylindrical portion 5 in advance using means such as vapor deposition.
, 8 may be held.
前記手法により、接合材の濡れ性に恭づく再接合面上に
おける接合効果および接合材の含浸に基づくアンカ効果
を得ることができ、これにより再接合筒部5,8、した
がってタービン羽根車1と回転軸2との接合強度を大幅
に向上させることができる。By the above method, it is possible to obtain a bonding effect on the re-bonded surface based on the wettability of the bonding material and an anchor effect based on the impregnation of the bonding material, thereby making it possible to obtain a bonding effect on the re-bonding surface based on the wettability of the bonding material and an anchoring effect based on the impregnation of the bonding material. The strength of the joint with the rotating shaft 2 can be significantly improved.
金属性接合材としては、5〜8重呈重量uを含むNi−
Cu系ろう材、14重量%Cr、4重量%Si、3.4
重量%Bを含むN i −Cr系ろう材、その他公知の
ろう材等が用いられる。As the metallic bonding material, Ni-
Cu-based brazing filler metal, 14% by weight Cr, 4% by weight Si, 3.4
A N i -Cr-based brazing filler metal containing B by weight %, other known brazing filler metals, etc. are used.
(a) 羽根車本体および軸本体用原料の調製セラミ
ック粉末
平均粒径0.5μm、最大粒径5μmのsi、N、
89重量%焼結助剤扮末
Y2O:l s重量%Al4
zOz 6重量%をボールミ
ルにて24時間混合する。(a) Preparation of raw materials for the impeller body and shaft body Ceramic powder with an average particle size of 0.5 μm and a maximum particle size of 5 μm, N,
89wt% sintering aid powder Y2O:l swt%Al4
6% by weight of zOz is mixed in a ball mill for 24 hours.
(bl 再接合筒部用原料の鋼製 先ず、溶出可能粒子を下記の手法を用いて製造する。(bl Material steel for rejoining cylinder part First, elutable particles are manufactured using the following method.
AlzOi 5.9重量%、Na、0 11.4重量
%、5jOz 25.2重量%、MgO13,0重世
%、Kz04.O重量%、BzOl 38.0重量%
、CaO2,5重量%よりなる配合物をボールミルにて
十分に混合し、その混合物を1400℃まで昇温しで溶
融し、その後熔融物を冷却固化する。その固化物に微粉
砕処理を施して平均粒径0.5μm、最大粒径5μmの
溶出可能粒子を得る。この溶出可能粒子の粒度分布はセ
ラミック粉末のそれに合せである。AlzOi 5.9% by weight, Na, 0 11.4% by weight, 5jOz 25.2% by weight, MgO 13.0% by weight, Kz04. O weight%, BzOl 38.0 weight%
, CaO2, 5% by weight are thoroughly mixed in a ball mill, the mixture is heated to 1400° C. and melted, and then the melt is cooled and solidified. The solidified product is subjected to a fine pulverization treatment to obtain elutable particles having an average particle size of 0.5 μm and a maximum particle size of 5 μm. The particle size distribution of the elutable particles is matched to that of the ceramic powder.
セラミック粉末
平均粒径0.5μm、最大粒径5μmのSi3N4
81重量%焼結助剤粉末
Y、On 2重量%A11i
es 3重量%溶出可能粒子
14重量%をボールミルにて24時
間混合する。Si3N4 ceramic powder average particle size 0.5μm, maximum particle size 5μm
81% by weight Sintering aid powder Y, On 2% by weight A11i
es 3% by weight elutable particles
14% by weight was mixed in a ball mill for 24 hours.
前記(a)の原料および分散媒として水を用い、スリッ
プキャスティング法を適用して羽根車本体1に対応する
成形体を得る。Using water as the raw material and dispersion medium in (a) above, a slip casting method is applied to obtain a molded body corresponding to the impeller body 1.
前記(blの原料および分散媒として水を用い、スリッ
プキャスティング法を適用して接合筒部5に対応する成
形体を得ると同時にその成形体と前記成形体とを一体化
してタービン羽根車1に対応する最終成形体を作製する
。Using water as the raw material and dispersion medium of the above (bl), a slip casting method is applied to obtain a molded body corresponding to the joint cylinder portion 5, and at the same time, the molded body and the molded body are integrated to form the turbine impeller 1. A corresponding final molded body is produced.
同様の手法により回転軸2に対応する最終成形体を作製
する。A final molded body corresponding to the rotating shaft 2 is produced by a similar method.
両最終成形体を焼結炉内に設置し、炉内にN2ガスを流
通させながら炉内温度を1600℃まで昇温し、この温
度を2時間維持する。Both final molded bodies are placed in a sintering furnace, and the temperature inside the furnace is raised to 1600°C while N2 gas is passed through the furnace, and this temperature is maintained for 2 hours.
この焼結処理によってタービン羽根車lおよび回転軸2
を得る。Through this sintering process, the turbine impeller l and the rotating shaft 2 are
get.
タービン羽根車lおよび回転軸2における密度は、理論
密度の95%以上であって非常に緻密であり、また室温
での曲げ強さは3点曲げ試験において85〜90kfr
/me”である。また破断面を走査型電子顕微鏡を用い
て観察したところ、結晶の成長に伴いセラミック粉末は
粒径3〜4μmの六角柱状晶となっており、結晶の異常
成長は認められていない。The density of the turbine impeller l and rotating shaft 2 is 95% or more of the theoretical density, which is very dense, and the bending strength at room temperature is 85 to 90 kfr in a three-point bending test.
/me''. When the fracture surface was observed using a scanning electron microscope, it was found that as the crystals grew, the ceramic powder became hexagonal columnar crystals with a particle size of 3 to 4 μm, and no abnormal crystal growth was observed. Not yet.
前記タービン羽根車1の接合筒部5に、以下に述べる溶
出処理を施す。The joint cylinder portion 5 of the turbine impeller 1 is subjected to the elution treatment described below.
25%の硝酸を50℃に加熱し、その硝酸を流通させる
と共にそれに超音波振動を付与し、この状況下にある硝
酸に接合筒部5を30分間浸消して溶出可能粒子を溶出
する。25% nitric acid is heated to 50° C., the nitric acid is circulated, and ultrasonic vibrations are applied to it, and the joint cylinder 5 is immersed in the nitric acid under this condition for 30 minutes to elute the elutable particles.
同様の手法により回転軸2の接合筒部8に溶出処理を施
す。The elution treatment is performed on the joint cylinder portion 8 of the rotating shaft 2 using a similar method.
再接合筒部5,8の重′Wk減少率は15.0%であり
、溶出可能粒子の略全量が溶出されたことになる。The weight reduction rate of the rejoined cylinder portions 5 and 8 was 15.0%, which means that almost all of the elutable particles were eluted.
再接合筒部5,8の破断面観察により、再接合筒部5,
8における気孔の大きさは約2μm、また気孔率は16
%であり、大部分の気孔が連続していることが確認され
ている。焼結後の気孔率は見掛上0%であったから、約
1%の閉鎖された気孔が存在することになる。By observing the fractured surfaces of the rejoined cylindrical parts 5 and 8, it was found that the rejoined cylindrical parts 5 and 8 were
The size of the pores in No. 8 is about 2 μm, and the porosity is 16
%, and it has been confirmed that most of the pores are continuous. Since the porosity after sintering was apparently 0%, approximately 1% of closed pores were present.
第3図に示すように、再接合筒部5.8を嵌合すると共
に接合筒部5の外面および接合筒部8の内面、したがっ
て両接合面間に、前記N i −Cu系ろう材を介在さ
せ、両者1.2をプレス機9に設置する。そして真空下
において上、下部パンチ10.11により角筒部6を圧
力200 kg f /龍2を以て加圧すると共にNi
−Cu系ろう材を1200℃に加熱して溶融し、その
Ni−Cu系ろう材によって再接合筒部5,8の接合面
を濡らし、またN 1−Cu系ろう材を再接合筒部5,
8の連続気孔に含浸させる。As shown in FIG. 3, while the re-joining cylindrical portion 5.8 is fitted, the Ni-Cu based brazing filler metal is applied to the outer surface of the joining cylindrical portion 5 and the inner surface of the joining cylindrical portion 8, that is, between the two joining surfaces. Both 1 and 2 are placed in the press machine 9. Then, under vacuum, the square tube part 6 is pressurized with a pressure of 200 kgf/dragon 2 using upper and lower punches 10 and 11, and Ni
-Cu-based brazing material is heated to 1200° C. to melt it, and the Ni-Cu-based brazing material wets the joint surfaces of the re-joining cylindrical sections 5 and 8, and the N1-Cu-based brazing material is applied to the re-joining cylindrical section 5. ,
8 continuous pores are impregnated.
前記接合作業後、回転軸2の角筒部6に仕上げ加工を施
して、第4図に示すタービン羽根車1および回転軸2の
接合体を得る。After the joining operation, the rectangular tube portion 6 of the rotary shaft 2 is subjected to finishing processing to obtain a joined body of the turbine impeller 1 and the rotary shaft 2 shown in FIG. 4.
この接合体においては、第5図に示すように再接合筒部
5,8の接合面間がN i −Cu系ろう材Bにより接
合され、またS t x N#を主体とするセラミック
材料C間の連続気孔PがNi −Cu系ろう材Bにより
埋められてアンカ効果が発生している。このN i −
Cu系ろう材Bの含浸状況を光学顕微鏡および走査型電
子顕微鏡にて観察したところ、含浸不良箇所のないこと
が確認されている。In this bonded body, as shown in FIG. 5, the bonding surfaces of the rejoining cylinder parts 5 and 8 are bonded by a Ni-Cu based brazing filler metal B, and a ceramic material C mainly composed of S t x N# is used. The continuous pores P between the two are filled with the Ni--Cu brazing filler metal B, creating an anchor effect. This Ni-
When the impregnation status of the Cu-based brazing material B was observed using an optical microscope and a scanning electron microscope, it was confirmed that there were no impregnated defects.
第6図は、再接合筒部5,8およびNi−Cu系ろう材
Bよりなる接合部分における温度と曲げ強さとの関係を
示し、第6図よりタービン羽根車1と回転軸2とは、そ
れらの一部を構成する、室温および高温下において高強
度な接合部分によって一体化されていることが明らかで
ある。FIG. 6 shows the relationship between temperature and bending strength at the rejoined cylindrical parts 5, 8 and the joint portion made of the Ni-Cu brazing filler metal B. From FIG. 6, the turbine impeller 1 and the rotating shaft 2 are It is clear that they are integrated by a joint part that has high strength at room and high temperatures.
また、前記接合体を、温度差700℃に急熱した後、直
ちに水中に投下し、この操作を繰返す、繰返し熱衝撃性
試験を行ったところ、セラミック材料単体部分には20
回でクラックを生じたが、前記接合部分にはクラックの
発生といったような異状のないことが確認されている。In addition, a repeated thermal shock test was conducted in which the bonded body was rapidly heated to a temperature difference of 700°C, then immediately dropped into water, and this operation was repeated.
However, it has been confirmed that there are no abnormalities such as cracks in the joint portion.
したがって、タービン羽根車lと回転軸2との接合強度
が大幅に向上していることが明らかである。Therefore, it is clear that the bonding strength between the turbine impeller 1 and the rotating shaft 2 is significantly improved.
(al 羽根車本体および軸本体用原料の調製セラミ
ック粉末
平均粒径0.4μm、最大粒径5μmのSi3Ng
90重量%焼結助剤粉末
yzos 5重量%A7!
20. 5重量%をボールミルに
て24時間混合する。(Al Preparation of raw materials for impeller body and shaft body Ceramic powder Si3Ng with average particle size of 0.4 μm and maximum particle size of 5 μm
90% by weight sintering aid powder yzos 5% by weight A7!
20. 5% by weight was mixed in a ball mill for 24 hours.
(bl 両接合筒部用原料の調製
溶出可能粒子において、そのA 7!20x 、M g
O酸成分はセラミック粉末であるS iz N4と固溶
する等の報告もあるため、実施例■の場合と配合量を変
え、また異常な結晶成長を抑制するため新たな成分とし
てハロゲン化物、実施例ではCaCl12を用い、溶出
可能粒子を下記の手法を用いて製造する。(bl Preparation of raw material for both jointed cylinder parts In the elutable particles, its A 7!20x, M g
There are also reports that the O acid component forms a solid solution with S iz N4, which is a ceramic powder, so the blending amount was changed from that in Example ①, and a new component, halide, was added to suppress abnormal crystal growth. The example uses CaCl12 and the elutable particles are produced using the following procedure.
AlzOi 8.6重世%、NazO10,3重量%
、5iOz 24.2重世%、MgO15,0重量%
、K2O2,1重量%、Btus 39.16重量%
、CaO0,6重量%、Ca CI! z 0104
重量%よりなる配合物をボールミルにて十分に混合し、
その混合物を1200℃まで昇温しで溶融し、その後溶
融物を冷却固化する。その固化物に微粉砕処理を施して
平均粒径1μm、最大粒径5μmの溶出可能粒子を得る
。AlzOi 8.6% by weight, NazO 10.3% by weight
, 5iOz 24.2% by weight, MgO 15.0% by weight
, K2O2, 1% by weight, Btus 39.16% by weight
, CaO0.6% by weight, Ca CI! z 0104
Thoroughly mix the composition consisting of % by weight in a ball mill,
The mixture is heated to 1200° C. to melt it, and then the melt is cooled and solidified. The solidified product is pulverized to obtain elutable particles having an average particle size of 1 μm and a maximum particle size of 5 μm.
また溶出可能粒子と焼結助剤とが反応したり、焼結助剤
のうち前記溶出処理により溶出されるものもあることが
懸念されるため焼結助剤を除き、セラミック粉末
平均粒径0.4μM、最大粒径5μmのS ii N−
93重量%
溶出可能粒子 7重吋%をボール
ミルにて24時間混合する。In addition, there is a concern that the elutable particles and the sintering aid may react, and that some of the sintering aid may be eluted during the elution process. .4μM, maximum particle size 5μm S ii N-
93% by weight elutable particles 7% by weight are mixed in a ball mill for 24 hours.
前記ta+の原料および分散媒として水を用い、スリッ
プキャスティング法を適用して羽根車本体4に対応する
成形体を得る。A molded body corresponding to the impeller body 4 is obtained by applying a slip casting method using water as the raw material of the ta+ and a dispersion medium.
前記fblの原料および分散媒として水を用い、スリッ
プキャスティング法を適用して接合筒部5に対応する成
形体を得ると同時にその成形体と前記成形体とを一体化
してタービン羽根車lに対応する最終成形体を作製する
。Using water as the raw material and dispersion medium for the fbl, a slip casting method is applied to obtain a molded body corresponding to the joint cylinder part 5, and at the same time, the molded body and the molded body are integrated to correspond to the turbine impeller l. A final molded body is produced.
同様の手法により回転軸2に対応する最終成形体を作製
する。A final molded body corresponding to the rotating shaft 2 is produced by a similar method.
両最終成形体を焼結炉内に設置し、炉内にN2ガスを流
通させながら炉内温度を1600℃まで昇温し、この温
度を2時間維持する。Both final molded bodies are placed in a sintering furnace, and the temperature inside the furnace is raised to 1600°C while N2 gas is passed through the furnace, and this temperature is maintained for 2 hours.
この焼結処理によってタービン羽根車1および回転軸2
を得る。Through this sintering process, the turbine impeller 1 and the rotating shaft 2 are
get.
このタービン羽根車lおよび回転軸2における密度は、
理論密度の95〜97%であって非常に緻密であり、ま
た室温での曲げ強さは3点曲げ試験において約80kg
f/am”である。また破断面を走査型電子顕微鏡を用
いて観察したところ、結晶成長に伴いセラミック粉末は
粒径3〜4μmの六角柱状晶となっており、結晶の異常
成長は認、められていない。The density in this turbine impeller l and rotating shaft 2 is:
It is extremely dense with a theoretical density of 95-97%, and its bending strength at room temperature is approximately 80 kg in a 3-point bending test.
When the fracture surface was observed using a scanning electron microscope, the ceramic powder became hexagonal columnar crystals with a grain size of 3 to 4 μm due to crystal growth, and no abnormal crystal growth was observed. Not recognized.
前記タービン羽根車1の接合筒部5に、以下に述べる溶
出処理を施す。The joint cylinder portion 5 of the turbine impeller 1 is subjected to the elution treatment described below.
25%の硝酸および0.1%のフッ化水素酸よりなる混
酸を50℃に加熱し、その混酸を流通させると共にそれ
に超音波振動を付与し、この状況下にある混酸に接合筒
部5を30分間浸漬して溶出可能粒子を溶出する。A mixed acid consisting of 25% nitric acid and 0.1% hydrofluoric acid is heated to 50° C., the mixed acid is circulated and ultrasonic vibration is applied to it, and the joint tube 5 is attached to the mixed acid under this condition. Soak for 30 minutes to elute the leachable particles.
同様の手法により回転軸2の接合筒部8に溶出処理を施
す。The elution treatment is performed on the joint cylinder portion 8 of the rotating shaft 2 using a similar method.
再接合筒部5,8の重量減少率は5.8%であり、溶出
可能粒子の配合量よりも少ないが、これは溶出可能粒子
の成分のうちA lz Oi 、Mg O等がSi、N
、と固溶し、またSiO2が窒化されたことに起因する
ものと思われる。The weight reduction rate of the rejoined cylinder parts 5 and 8 is 5.8%, which is less than the blended amount of the elutable particles, but this is because among the components of the elutable particles, A lz Oi , Mg O, etc.
This is thought to be due to the solid solution of SiO2 and nitridation of SiO2.
再接合筒部5.8の破断面観察により、再接合筒部5,
8における連続気孔の大きさは最大約3μm、また気孔
率は15%であり、閉鎖気孔はなく全ての気孔が連続し
ていることが確認されている。Observation of the fractured surface of the rejoined cylindrical portion 5.8 revealed that the rejoined cylindrical portion 5.
The size of the continuous pores in Sample No. 8 was approximately 3 μm at the maximum, and the porosity was 15%, and it was confirmed that there were no closed pores and all pores were continuous.
第3図に示すように、再接合筒部5,8を嵌合すると共
に接合筒部5の外面および接合筒部8の内面、したがっ
て両接合面間に前記Ni−Cr系ろう材を介在させ、両
者1. 2をプレス機9に設置する。そしてNz、Ar
等による不活性ガス雰囲気下において上、下部パンチ1
0.11により角筒部6を圧力150 kg f /s
s”を以て加圧すると共にNi−Cr系ろう材を120
0℃に加熱して/8融し、そのN i −Cr系ろう材
によって再接合筒部5,8の接合面を濡らし、またNi
−Cr系ろう材を再接合筒部5,8の連続気孔に含浸さ
せる。As shown in FIG. 3, the re-joining cylindrical parts 5 and 8 are fitted together, and the Ni-Cr brazing filler metal is interposed between the outer surface of the joining cylindrical part 5 and the inner surface of the joining cylindrical part 8, and therefore between both the joining surfaces. , both 1. 2 is installed in the press machine 9. and Nz, Ar
Upper and lower punches 1 under an inert gas atmosphere such as
0.11, the square tube part 6 is subjected to a pressure of 150 kg f /s
s'' and Ni-Cr brazing filler metal at 120℃.
It is heated to 0°C to melt /8, and the joint surfaces of the rejoined cylinder parts 5 and 8 are wetted with the Ni-Cr brazing filler metal, and the Ni
- Cr-based brazing material is impregnated into the continuous pores of the rejoining cylindrical parts 5 and 8.
前記接合作業後、回転軸2の角筒部6に仕上げ加工を施
して、第4図に示すタービン羽根車Iおよび回転軸2の
接合体を得る。After the joining operation, the rectangular tube portion 6 of the rotary shaft 2 is subjected to finishing processing to obtain a joined body of the turbine impeller I and the rotary shaft 2 shown in FIG. 4.
この接合体においては、第5図に示すように接合筒部5
,8の接合面間がNi−Cr系ろう材Bにより接合され
、またSiI Naを主体とするセラミック材料C間の
連続気孔PがNi−Cr系ろう材Bにより埋められてア
ンカ効果が発生している。In this joined body, as shown in FIG.
. ing.
再接合筒部5,8およびN i −Cr系ろう材Bより
なる接合部分の室温での曲げ強さは、3点曲げ試験にお
いて90kgf/w+*”で、セラミック材料Cの曲げ
強さ85〜90 k+r f / am”と略同等であ
り、また室温〜500°Cにおいて接合部分の強度劣化
も殆どみられず、曲げ強さ80〜100 kgf/am
2を保持していることが判明している。したがって実施
例■同様にタービン羽根車1と回転軸2との接合強度が
大幅に向上していることが明らかである。The bending strength at room temperature of the joint portion made of the rejoined cylindrical parts 5, 8 and the Ni-Cr brazing filler metal B was 90 kgf/w+*" in a three-point bending test, and the bending strength of the ceramic material C was 85~ 90 k+r f/am", and there is almost no deterioration in the strength of the joint at room temperature to 500°C, and the bending strength is 80 to 100 kgf/am.
It has been found that it holds 2. Therefore, it is clear that the joint strength between the turbine impeller 1 and the rotary shaft 2 is significantly improved as in Example 2.
なお、本発明はタービン羽根車と回転軸との接合に限ら
ず、各種セラミック体の接合、例えば板状セラミック体
と板状セラミック体の接合等にも適用される。Note that the present invention is not limited to joining a turbine impeller and a rotating shaft, but is also applicable to joining various ceramic bodies, such as joining plate-shaped ceramic bodies to plate-shaped ceramic bodies.
C0発明の効果
本発明によれば、第1および第2セラミック体の接合面
に対する接合材の濡れ性に基づく接合効果および両セラ
ミック体の連続気孔への接合材の含浸に基づくアンカ効
果を得、これにより両セラミック体の接合強度を大幅に
向上させることができる。C0 Effects of the Invention According to the present invention, a bonding effect based on the wettability of the bonding material to the bonding surfaces of the first and second ceramic bodies and an anchoring effect based on the impregnation of the bonding material into the continuous pores of both ceramic bodies are obtained. This makes it possible to significantly improve the bonding strength between both ceramic bodies.
第1図+a)はタービン羽根車の縦断正面図、第1図(
blは回転軸の要部縦断正面図、第2図はタービン羽根
車および回転軸における接合筒部の気孔率と曲げ強さと
の関係を示すグラフ、第3図は接合材の含浸作業を示す
縦断正面図、第4図は接合体の要部縦断正面図、第5図
は第4図■矢示部の拡大図、第6図はタービン羽根車と
回転軸との接合部分における曲げ強さと温度との関係を
示すグラフである。
1・・・第1セラミック体としてのタービン羽根車、2
・・・第2セラミック体としての回転軸、B・・・金属
性接合材としてのNi−Cu系ろう材、Ni−Cr系ろ
う材、C・・・セラミンク材料、P・・・連続気孔
特 許 出 願 人 本田技研工業株式会社代理人
弁理士 落 合 健第1図
(a〕 (b)第
4図
第3図
第5図
第2図
気化率(’/、)
第6図
温度(Co)Figure 1 + a) is a longitudinal sectional front view of the turbine impeller; Figure 1 (
bl is a longitudinal cross-sectional front view of the main part of the rotating shaft, Fig. 2 is a graph showing the relationship between the porosity and bending strength of the joint cylinder of the turbine impeller and the rotating shaft, and Fig. 3 is a longitudinal cross-sectional view showing the impregnation work of the bonding material. Front view, Figure 4 is a longitudinal sectional front view of the main part of the joined body, Figure 5 is an enlarged view of the part indicated by the arrow in Figure 4, and Figure 6 is the bending strength and temperature at the joint between the turbine impeller and the rotating shaft. It is a graph showing the relationship between 1... Turbine impeller as a first ceramic body, 2
...Rotating shaft as a second ceramic body, B...Ni-Cu brazing filler metal, Ni-Cr brazing filler metal as a metallic bonding material, C...ceramink material, P...continuous pore characteristics Applicant: Agent of Honda Motor Co., Ltd.
Ken Ochiai, Patent Attorney Figure 1 (a) (b) Figure 4 Figure 3 Figure 5 Figure 2 Evaporation rate ('/,) Figure 6 Temperature (Co)
Claims (1)
ミック体を接合するに当り、前記第1および第2セラミ
ック体より、それらの成形に先立って配合された溶出可
能粒子を溶出し、両セラミック体に、それらの接合面に
開口する多数の連続気孔を形成する工程と;前記第1お
よび第2セラミック体の前記両接合面間に介在させた金
属性接合材を溶融し、該接合材を前記両セラミック体の
前記連続気孔に含浸させる工程と;を用いることを特徴
とするセラミック体の接合方法。When joining the first and second ceramic bodies obtained through the molding and sintering process, the elutable particles blended prior to molding are eluted from the first and second ceramic bodies, and both ceramic bodies are bonded together. forming a large number of continuous pores in the body that open to the bonding surfaces thereof; melting a metallic bonding material interposed between the bonding surfaces of the first and second ceramic bodies; A method for joining ceramic bodies, comprising: impregnating the continuous pores of both ceramic bodies.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP61286140A JPH0653621B2 (en) | 1986-12-01 | 1986-12-01 | How to join ceramics |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP61286140A JPH0653621B2 (en) | 1986-12-01 | 1986-12-01 | How to join ceramics |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS63139071A true JPS63139071A (en) | 1988-06-10 |
JPH0653621B2 JPH0653621B2 (en) | 1994-07-20 |
Family
ID=17700453
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP61286140A Expired - Fee Related JPH0653621B2 (en) | 1986-12-01 | 1986-12-01 | How to join ceramics |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0653621B2 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0288470A (en) * | 1988-09-24 | 1990-03-28 | Eagle Ind Co Ltd | Method for joining silicon carbide material |
JP2002255666A (en) * | 2001-02-27 | 2002-09-11 | Kyocera Corp | Jointed body and method of producing the same |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3045314U (en) * | 1997-07-14 | 1998-01-27 | 玉井環境システム株式会社 | Gaze guidance sign for guard rope |
DE10239416B4 (en) * | 2002-08-28 | 2005-03-03 | Robert Bosch Gmbh | Process for the preparation of a ceramic layer composite body |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS59141466A (en) * | 1983-01-31 | 1984-08-14 | 三井造船株式会社 | Ceramic member bonding method |
-
1986
- 1986-12-01 JP JP61286140A patent/JPH0653621B2/en not_active Expired - Fee Related
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS59141466A (en) * | 1983-01-31 | 1984-08-14 | 三井造船株式会社 | Ceramic member bonding method |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0288470A (en) * | 1988-09-24 | 1990-03-28 | Eagle Ind Co Ltd | Method for joining silicon carbide material |
JP2002255666A (en) * | 2001-02-27 | 2002-09-11 | Kyocera Corp | Jointed body and method of producing the same |
JP4666791B2 (en) * | 2001-02-27 | 2011-04-06 | 京セラ株式会社 | CONNECTED BODY AND METHOD FOR PRODUCING THE SAME |
Also Published As
Publication number | Publication date |
---|---|
JPH0653621B2 (en) | 1994-07-20 |
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