JPH11281259A - Continuous atmospheric furnace - Google Patents

Continuous atmospheric furnace

Info

Publication number
JPH11281259A
JPH11281259A JP12158298A JP12158298A JPH11281259A JP H11281259 A JPH11281259 A JP H11281259A JP 12158298 A JP12158298 A JP 12158298A JP 12158298 A JP12158298 A JP 12158298A JP H11281259 A JPH11281259 A JP H11281259A
Authority
JP
Japan
Prior art keywords
gas
furnace
atmosphere
heat treatment
continuous heat
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
Application number
JP12158298A
Other languages
Japanese (ja)
Inventor
Sunao Tanaka
直 田中
Kazuo Watabe
一夫 渡部
Kazumi Motokisawa
一実 元木沢
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tokai Konetsu Kogyo Co Ltd
Original Assignee
Tokai Konetsu Kogyo Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Tokai Konetsu Kogyo Co Ltd filed Critical Tokai Konetsu Kogyo Co Ltd
Priority to JP12158298A priority Critical patent/JPH11281259A/en
Publication of JPH11281259A publication Critical patent/JPH11281259A/en
Pending legal-status Critical Current

Links

Abstract

PROBLEM TO BE SOLVED: To separate atmosphere by simply providing an atmospheric interference band of abnormal gas in a furnace through the use of an entire or combinational gas separation means of gas blowing/discharging structures and gas diffusion blocking structure at several positions in the longitudinal direction of a tunnel furnace. SOLUTION: The furnace has adjacent gas curtain structures 1, 2 for separating different gas atmosphere bands and provided with a heat insulating brick layer of furnace, and means 11 for blocking different kinds of gas being diffused between joints. The gas curtain structure has a barrier wall for sectioning the inside of the furnace constructed of high alumina deformed bricks 1. Gas curtain gas is supplied from a gas supply piping 2 into an equalizing chamber 3 and ejected through a large number of nozzles 4 into the furnace. Exhaust gas is discharged to the outside through a duct 6 of deformed bricks disposed at the end of several exhaust gas introduction 5 grooves made in the outer surface of the barrier wall.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、主に機能性電子セ
ラミック素子などを焼成する炉に於いて、該素子の機能
性を引き出すために必要な焼成炉の焼成雰囲気、焼成技
術に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a furnace for firing functional electronic ceramic elements and the like, and more particularly to a firing atmosphere and a firing technique of a firing furnace necessary for bringing out the functionality of the elements.

【0002】[0002]

【従来の技術】一般の雰囲気炉は、単一雰囲気または、
2種類以上のガスを均一に混合したガスを炉内に導入し
て所定の雰囲気を構成し、処理品の酸化を防止したり、
還元処理する目的で使用されている。しかしながら、近
年、特に一部の機能性セラミックの焼成については、そ
の焼成過程において酸化→還元→再酸化、あるいは同種
のガスであっても、その中に含む水蒸気の分圧を変化さ
せたそれぞれの雰囲気の領域をつくることが必要になっ
てきている。従来、この様な場合、一連のトンネル炉の
中で雰囲気ガスを可変させることが非常に困難なため
に、例えば、酸化雰囲気専用炉と還元雰囲気専用炉を別
個に設けてそれぞれの目的に適合した処理を行ってい
た。そのため一度加熱した処理品を大気温度付近まで冷
却してから、再度別の雰囲気ガスで調整された別個の専
用炉へ移して焼成していた。このため、設備費が高価に
なる。再加熱するためのエネルギーが必要、処理品の移
し替え(移動)労力が必要、熱処理時間が長い、設置ス
ペースが広くいる、等々のデメリットがあった。
2. Description of the Related Art A general atmosphere furnace has a single atmosphere or
A gas in which two or more kinds of gases are uniformly mixed is introduced into a furnace to form a predetermined atmosphere to prevent oxidation of a processed product,
It is used for the purpose of reduction treatment. However, in recent years, especially for the firing of some functional ceramics, in the firing process, oxidation, reduction, and reoxidation, or even with the same type of gas, the respective partial pressures of the steam contained therein have been changed. It is becoming necessary to create an atmosphere area. Conventionally, in such a case, since it is very difficult to change the atmosphere gas in a series of tunnel furnaces, for example, a furnace dedicated to an oxidizing atmosphere and a furnace dedicated to a reducing atmosphere are separately provided to meet respective purposes. Processing was being performed. For this reason, once heated, the treated product is cooled to a temperature close to the atmospheric temperature, and then transferred again to a separate dedicated furnace adjusted with another atmospheric gas for firing. For this reason, equipment costs are high. There are disadvantages such as the need for energy for reheating, the labor for transferring (moving) the processed product, the long heat treatment time, the large installation space, and the like.

【0003】[0003]

【発明が解決しようとする課題】本発明は、一連のトン
ネル炉の中で性状の異なるガスを、僅かな雰囲気の干渉
帯を設けるだけでほぼ完全に雰囲気を分離することが可
能な炉を提供して、焼成時間の短縮、省エネ、省コス
ト、省労力、省スペイスを図ることを目的とするもので
ある。
SUMMARY OF THE INVENTION The present invention provides a furnace in which a series of tunnel furnaces can be used to completely separate the atmospheres of gases having different properties by providing an interference band having a slight atmosphere. The purpose of the present invention is to reduce the firing time, save energy, save cost, save labor, and save space.

【0004】[0004]

【課題を解決するための手段】本発明は、図1に示すよ
うにトンネル炉の長手方向の数カ所に、ガスの分離手段
として、図1の1,2に示すガスの吹込み、排気構造と
11,12に示すガス拡散遮断構造の全部、または、何
れかの構造を組み合わせて使用することによって、一連
のトンネル炉の中で性質の異なったガスの雰囲気帯を構
成可能な炉を提供する。即ち、本発明は、図1,2の
1,2,11,12に示す構造、即ち、1,2は相隣接
する異なるガス雰囲気帯を分離するための、一種のガス
カーテン構造である。11,12は炉の断熱レンガ層お
よび、その目地間を拡散してくる異種のガスを遮断する
ための手段である。図1,2に示すガスカーテン構造
は、請求項2に記載されているもので、各炉内を区分す
る隔壁レンガ1をガスが透過しないハイアルミナ質の異
形状レンガで構成する。該隔壁レンガ1はその内部に炉
外からガス供給用配管2で供給されるガスカーテン用ガ
ス(一般には窒素ガス等の中性ガスが用いられる。)を
導く均圧室3と、均圧室3へ導かれたガスを、炉内に噴
出させる多数のガス噴出ノズル4を有している。該ガス
噴出ノズル4の取り付け個数とノズル径は、炉内の有効
開口幅と開口高さによって、ノズルからの最適なガスの
噴出速度を計算して決められるが、通常その速度は12
〜18m/sec程度である。また、該隔壁レンガの外
表面には排気ガスを炉外に導く数条の排気ガス誘導溝5
が掘られている。排気ガス誘導溝5の端部は断熱レンガ
層の中に設けられ、異形状レンガで作られたダクト6に
集合され、そこからセラミックチューブ7を通して炉外
に導かれ、更に、ガス排気用配管8を通して強制排気ブ
ロワー9へ導かれる。該ブロワー9は炉内雰囲気の状態
に応じて、インバーターを介してガスの排気量をコント
ロールできるようになっている。図2に示す拡散ガス遮
断板11と断熱レンガ目地の気密接着用ペースト12は
請求項3に記載されているもので、異なるガス雰囲気帯
を相互に拡散してくるガスを遮断するものである。拡散
ガス遮断板11は、一般には可とう性のある金属板、例
えば、インコネルなどの薄板が使用されている。また、
とくに高温にさらされる部分にはセラミック質の板、例
えばSiC、SiC−Si、ハイアルミナ質の薄板が用
いられる。
According to the present invention, as shown in FIG. 1, gas blowing and exhaust structures shown in FIGS. By using all or any of the gas diffusion blocking structures shown in 11 and 12 in combination, it is possible to provide a furnace capable of forming an atmosphere zone of gas having different properties in a series of tunnel furnaces. That is, the present invention is a structure shown in FIGS. 1 and 2 as 1, 2, 11 and 12, that is, 1 and 2 are a kind of gas curtain structure for separating adjacent different gas atmosphere zones. Numerals 11 and 12 are means for blocking the different types of gas diffusing between the insulating brick layer of the furnace and the joints. The gas curtain structure shown in FIGS. 1 and 2 is the one described in claim 2, wherein the partition wall brick 1 that partitions the inside of each furnace is made of a high-alumina-shaped irregular-shaped brick that does not allow gas to permeate. The equalizing chamber 3 for introducing a gas for gas curtain (generally, a neutral gas such as nitrogen gas) supplied from outside the furnace by a gas supply pipe 2 to the inside of the partition brick 1, and an equalizing chamber It has a number of gas ejection nozzles 4 for ejecting the gas guided to 3 into the furnace. The number of nozzles and the diameter of the gas ejection nozzles 4 are determined by calculating the optimum gas ejection speed from the nozzles according to the effective opening width and opening height in the furnace.
1818 m / sec. Also, on the outer surface of the partition wall brick, there are provided several exhaust gas guide grooves 5 for guiding exhaust gas to the outside of the furnace.
Has been dug. The end of the exhaust gas guide groove 5 is provided in a heat insulating brick layer, is assembled in a duct 6 made of irregular-shaped brick, is led out of the furnace through a ceramic tube 7, and further has a gas exhaust pipe 8. Through the forced exhaust blower 9. The blower 9 can control the amount of gas exhausted via an inverter according to the state of the furnace atmosphere. The airtight bonding paste 12 between the diffusion gas blocking plate 11 and the insulating brick joint shown in FIG. 2 is the one described in claim 3 and blocks the gas that diffuses into different gas atmosphere zones. As the diffusion gas blocking plate 11, a flexible metal plate, for example, a thin plate such as Inconel is generally used. Also,
In particular, a ceramic plate, for example, a thin plate of SiC, SiC-Si, or high alumina is used for a portion exposed to a high temperature.

【0005】[0005]

【発明の実施の形態】図3は以上に述べた隔壁部におけ
るガスの流れを縦断面で模視した図である。ガスカーテ
ン用ガスは一定の速度と角度の広がりをもって炉内に噴
出された後、炉内を通過する処理品または、対面から噴
出されるカーテン用ガス等と衝突して速度を失い、隔壁
レンガの外表面の掘られた溝を通して、強制排気してい
るダクトへと導かれる。また、同様に炉内に滞留してい
るガスも図3の矢印の方向へ向かって移動し、隔壁レン
ガの外表面に掘られた溝を通して炉外へ強制排気され
る。従って、隔壁レンガの前後に存在する雰囲気は、互
いに混合することなしに分離することが出来る。しかし
ながら、ガスカーテン用ガス、炉内への供給ガス、強制
排気されるガスの排気速度がうまくバランスしていない
と良好な結果は得られない。即ち、排気されるガス量の
総和は常に、炉内に導入されるガスカーテン用ガスと雰
囲気構成用ガスとの合計量より少ないこと、雰囲気構成
用ガス帯の雰囲気圧力が大気圧より高くなるように、そ
れぞれのガス量、ガス圧力を制御しておかなければなら
ない。
DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 is a view schematically showing the flow of gas in the above-mentioned partition wall in a vertical section. After the gas for gas curtain is injected into the furnace at a constant speed and at a certain angular spread, it collides with the processed product passing through the furnace, or the gas for curtain injected from the opposite side, and loses its speed. It is led to a forced exhaust duct through a dug groove on the outer surface. Similarly, the gas remaining in the furnace also moves in the direction of the arrow in FIG. 3 and is forcibly exhausted out of the furnace through a groove dug in the outer surface of the partition wall brick. Therefore, the atmospheres before and after the partition brick can be separated without mixing with each other. However, good results cannot be obtained unless the exhaust speeds of the gas for the gas curtain, the gas supplied into the furnace, and the gas to be forcibly exhausted are not well balanced. That is, the sum of the exhausted gas amounts is always smaller than the total amount of the gas curtain gas and the atmosphere forming gas introduced into the furnace, and the atmospheric pressure of the atmosphere forming gas zone is higher than the atmospheric pressure. In addition, each gas amount and gas pressure must be controlled.

【0006】[0006]

【実施例】図1は、炉の有効間口がW400×H200
mm炉長が20,000mmの連続式雰囲気トンネル炉
の縦断面の一部を示したものである。本炉に於いては、
入り口部から順に、窒素ガス+微量酸素、窒素95%+
水素5%+水分(露点+50℃)、窒素95%+水素5
%+水分(露点+10℃)、窒素+微量酸素の4段階で
炉内の雰囲気を変更している。この様な、雰囲気を必要
とする熱処理は、主に、セラミックと金属をメタライズ
したり積層焼結する場合である。上記の雰囲気はセラミ
ックと金属ペーストを積層焼結する場合の一例で、第一
の雰囲気は、グリーン状態の処理品からその成形助剤で
あるバインダーを除去するために必要な雰囲気であり、
第二の雰囲気は焼成に、第三の雰囲気はセラミックの焼
結と金属の焼付に、第四の雰囲気はセラミックの再酸化
と冷却を目的として構成した雰囲気炉である。なお、本
炉に於いては、各雰囲気帯における雰囲気の状況をそれ
ぞれの雰囲気帯に設けられた、酸素、水素、露点等の分
析計で管理し、ガスの供給、排気ガス量の制御にフィー
ドバックされている。
FIG. 1 shows that the effective width of the furnace is W400 × H200.
1 shows a part of a vertical section of a continuous atmosphere tunnel furnace having a furnace length of 20,000 mm. In this furnace,
Nitrogen gas + trace oxygen, nitrogen 95% +
5% hydrogen + moisture (dew point + 50 ° C), 95% nitrogen + 5 hydrogen
The atmosphere in the furnace is changed in four stages of% + moisture (dew point + 10 ° C.), nitrogen + trace oxygen. Such a heat treatment requiring an atmosphere is mainly when metallizing and laminating and sintering ceramic and metal. The above atmosphere is an example of laminating and sintering the ceramic and metal paste, the first atmosphere is an atmosphere necessary to remove the binder as a molding aid from the green processed product,
The second atmosphere is for firing, the third atmosphere is for sintering ceramic and baking metal, and the fourth atmosphere is an atmosphere furnace for reoxidizing and cooling the ceramic. In this furnace, the condition of the atmosphere in each atmosphere zone is managed by analyzers provided for each atmosphere zone, such as oxygen, hydrogen, dew point, etc., and fed back to gas supply and exhaust gas control. Have been.

【0007】[0007]

【発明の効果】以上に述べたように、本発明に係わる方
法で一連のトンネル炉の炉内ガス雰囲気を分離すること
によって、これまで、一種類の条件の異なる処理品を焼
成するのに、2基ないし複数基の雰囲気を異にする専用
トンネル炉を必要としていたが、本発明による構造を有
する一連のトンネル炉を構築することによって、全く異
なった条件で処理しなければならなかった熱処理の行程
を、一連の炉で処理出来ることになり、設備基数の削
減、(設備費の大幅な削減)、処理品の昇降温に要する
熱エネルギーロス、処理品の移動に伴う労力、設置スペ
ースの削減等が可能になり、産業上の効果は極めて大で
ある。
As described above, by separating the gas atmosphere in a series of tunnel furnaces by the method according to the present invention, it has been possible to sinter one type of processed product under different conditions. Although a special tunnel furnace having two or more different atmospheres was required, by constructing a series of tunnel furnaces having a structure according to the present invention, heat treatment which had to be performed under completely different conditions was required. The process can be processed in a series of furnaces, reducing the number of equipment, (significant reduction in equipment cost), heat energy loss required for raising and lowering the temperature of processed products, labor involved in moving processed products, and reducing installation space Etc. are possible, and the industrial effect is extremely large.

【図面の簡単な説明】[Brief description of the drawings]

【図1】本発明による雰囲気ガス分離構造を示した炉の
縦断面図。
FIG. 1 is a vertical sectional view of a furnace showing an atmosphere gas separation structure according to the present invention.

【図2】本発明による雰囲気ガス分離構造を示した横断
面図。
FIG. 2 is a cross-sectional view showing an atmosphere gas separation structure according to the present invention.

【図3】本発明による雰囲気ガス分離部のガスの流れを
模視した図。
FIG. 3 is a diagram simulating the flow of gas in an atmosphere gas separation unit according to the present invention.

【符号の説明】[Explanation of symbols]

1.隔壁レンガ 2.ガス供給用配管 3.均圧室 4.ガス噴出ノズル 5.排気ガス誘導溝 6.ダクト 7.セラミックチューブ 8.ガス排気用配管 9.ブロワー 10.ガス供給用流量計 11.拡散ガス遮断板 12.気密接着用ペースト 13.台板 14.発熱体 15.炉殻 16.断熱レンガ 17.内張耐火レンガ 1. Partition wall brick 2. Gas supply piping 3. Equalizing chamber 4. Gas jet nozzle 5. Exhaust gas guide groove 6. Duct 7. Ceramic tube 8. 8. Gas exhaust piping Blower 10. Flow meter for gas supply 11. Diffusion gas blocking plate 12. 12. Airtight bonding paste Base plate 14. Heating element 15. Furnace shell 16. Insulated brick 17. Lining fire brick

Claims (3)

【特許請求の範囲】[Claims] 【請求項1】 プッシャ、ローラハース等の処理物連続
搬送装置を有するトンネル型電気加熱式連続熱処理炉で
あって、搬送方向に沿って炉体を2ないしそれ以上のゾ
ーンに分け、毎ゾーン毎に成分比を任意に調整した雰囲
気ガスを炉内に導入し、容易に各ゾーン内を実質上該成
分比の雰囲気に保つことを可能ならしめ、よって熱処理
過程の進行に伴い、処理雰囲気を容易に加減、調整でき
る構造を有する連続熱処理炉。
1. A tunnel-type electric heating type continuous heat treatment furnace having a treatment object continuous conveyance device such as a pusher, a roller hearth, etc., wherein a furnace body is divided into two or more zones along a conveyance direction, and each zone is divided into two or more zones. Atmosphere gas whose component ratio is arbitrarily adjusted is introduced into the furnace, so that it is possible to easily maintain the inside of each zone substantially at the atmosphere of the component ratio, so that the processing atmosphere can be easily changed with the progress of the heat treatment process. A continuous heat treatment furnace with a structure that can be adjusted and adjusted.
【請求項2】 上記において、異なる雰囲気のゾーンの
間に、炉内内張煉瓦の全面あるいは一部に多数のガス導
入用の細孔を設けたガスカーテン構造を有する隔壁を設
け、かつ該隔壁はその両面に空隙のある溝あるいは複数
の孔を設け、炉外への強制排気を可能ならしめた構造を
有する請求項1記載の連続熱処理炉。
2. In the above, a partition having a gas curtain structure in which a large number of pores for introducing gas are provided on the entire surface or a part of a brick in a furnace between zones of different atmospheres, and the partition is provided. 2. The continuous heat treatment furnace according to claim 1, wherein the continuous heat treatment furnace has a structure in which a groove or a plurality of holes having voids is provided on both surfaces thereof to enable forced exhaust to the outside of the furnace.
【請求項3】 上記ガスカーテン構造部前後の外側の炉
内耐火、断熱煉瓦部において、搬送方向に対し、ガスカ
ーテン部手前およびその後部にガス拡散防止用遮断板を
設け、さらに該箇所の煉瓦目地部に気密性に優れたガス
漏れ防止ペーストを塗布・充填したガス拡散遮断構造を
有する請求項2記載の連続熱処理炉。
3. A gas diffusion preventing shut-off plate is provided before and after the gas curtain portion in the transport direction in the fireproof and heat-insulating brick portion outside the furnace before and after the gas curtain structure portion. 3. The continuous heat treatment furnace according to claim 2, wherein the joint has a gas diffusion blocking structure in which a gas leakage prevention paste having excellent airtightness is applied and filled.
JP12158298A 1998-03-27 1998-03-27 Continuous atmospheric furnace Pending JPH11281259A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP12158298A JPH11281259A (en) 1998-03-27 1998-03-27 Continuous atmospheric furnace

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP12158298A JPH11281259A (en) 1998-03-27 1998-03-27 Continuous atmospheric furnace

Publications (1)

Publication Number Publication Date
JPH11281259A true JPH11281259A (en) 1999-10-15

Family

ID=14814819

Family Applications (1)

Application Number Title Priority Date Filing Date
JP12158298A Pending JPH11281259A (en) 1998-03-27 1998-03-27 Continuous atmospheric furnace

Country Status (1)

Country Link
JP (1) JPH11281259A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102515139A (en) * 2011-11-10 2012-06-27 青岛科技大学 Two-chamber vertical vacuum controllable atmosphere furnace for continuously preparing nano materials through gas-phase method
JP2016536557A (en) * 2013-09-27 2016-11-24 エーディーピーヴィー シーアイジーエス リミテッド Furnace with convection and radiant heating
JP2016536558A (en) * 2013-09-27 2016-11-24 エーディーピーヴィー シーアイジーエス リミテッド Furnace with sealed temperature controlled part
JP2018505376A (en) * 2015-01-08 2018-02-22 リンデ アクチエンゲゼルシャフトLinde Aktiengesellschaft Apparatus and method for controlling a sintering process
JP2022042560A (en) * 2020-09-03 2022-03-15 株式会社ノリタケカンパニーリミテド Heat treatment furnace and method for producing inorganic material using heat treatment furnace

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102515139A (en) * 2011-11-10 2012-06-27 青岛科技大学 Two-chamber vertical vacuum controllable atmosphere furnace for continuously preparing nano materials through gas-phase method
JP2016536557A (en) * 2013-09-27 2016-11-24 エーディーピーヴィー シーアイジーエス リミテッド Furnace with convection and radiant heating
JP2016536558A (en) * 2013-09-27 2016-11-24 エーディーピーヴィー シーアイジーエス リミテッド Furnace with sealed temperature controlled part
JP2018505376A (en) * 2015-01-08 2018-02-22 リンデ アクチエンゲゼルシャフトLinde Aktiengesellschaft Apparatus and method for controlling a sintering process
JP2022042560A (en) * 2020-09-03 2022-03-15 株式会社ノリタケカンパニーリミテド Heat treatment furnace and method for producing inorganic material using heat treatment furnace

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