JPH0841578A - Oxide dispersion reinforced heat resistant sintered alloy excellent in toughness at high temperature - Google Patents
Oxide dispersion reinforced heat resistant sintered alloy excellent in toughness at high temperatureInfo
- Publication number
- JPH0841578A JPH0841578A JP18007294A JP18007294A JPH0841578A JP H0841578 A JPH0841578 A JP H0841578A JP 18007294 A JP18007294 A JP 18007294A JP 18007294 A JP18007294 A JP 18007294A JP H0841578 A JPH0841578 A JP H0841578A
- Authority
- JP
- Japan
- Prior art keywords
- metal
- sintered alloy
- high temperature
- toughness
- heat resistant
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Powder Metallurgy (AREA)
- Manufacture Of Alloys Or Alloy Compounds (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、高温靱性にすぐれる酸
化物分散強化耐熱焼結合金に関する。FIELD OF THE INVENTION The present invention relates to an oxide dispersion strengthened heat resistant sintered alloy having excellent high temperature toughness.
【０００２】[0002]
【従来技術】出願人は、以前に、高温における強度及び
耐酸化性にすぐれた酸化物分散強化耐熱焼結合金を提案
した(特開平４−３２５６５１)。2. Description of the Related Art The applicant has previously proposed an oxide dispersion strengthened heat resistant sintered alloy having excellent strength and oxidation resistance at high temperatures (Japanese Patent Laid-Open No. 4-325651).
【０００３】この合金は、Ｃｒ基金属粉末とＹ2Ｏ3粉末
の混合粉末をアトライタ装置（高エネルギー型ボールミ
ル）の中で攪拌してメカニカルアロイング(機械的合金
化)を施すことにより、Ｃｒ基金属のマトリックス中に
平均粒径約0.1μm以下の微細なＹ2Ｏ3が0.2〜2.0重量％
略均一に分散した組織を有する粉末を調製し、該粉末を
適当な金属カプセルに充填した後、脱気密封し、約1000
〜1300℃の温度にて、約1000〜2000kgf/cm2の圧力下で
熱間静水圧処理(ＨＩＰ)することによって得られる。In this alloy, a mixed powder of Cr-based metal powder and Y 2 O 3 powder is agitated in an attritor device (high energy type ball mill) and subjected to mechanical alloying (mechanical alloying) to obtain Cr. 0.2 to 2.0% by weight of fine Y 2 O 3 having an average particle size of about 0.1 μm or less in the matrix of the base metal
A powder having a substantially uniformly dispersed structure was prepared, and the powder was filled in an appropriate metal capsule, then degassed and sealed, and then about 1000
It is obtained by hot isostatic pressing (HIP) at a temperature of ~ 1300 ° C and a pressure of about 1000-2000 kgf / cm 2 .
【０００４】この焼結合金は、Ｙ2Ｏ3粒子が金属マトリ
ックス中の転位の進展を阻害する作用を有しており、結
晶粒界が強固であり、高温下でも結晶粒の変形が阻害さ
れ、高温クリープ強度に関してすぐれた性能を発揮す
る。一方、結晶粒界が強固で変形しにくいことは、靱性
の点で不利であることを意味する。合金の用途によって
は、高温クリープ強度は多少低下しても、高温靱性を重
要視されることがある。In this sintered alloy, the Y 2 O 3 particles have an effect of inhibiting the development of dislocations in the metal matrix, the grain boundaries are strong, and the deformation of the crystal grains is inhibited even at high temperatures. Excellent performance in high temperature creep strength. On the other hand, the fact that the crystal grain boundaries are strong and difficult to deform means that it is disadvantageous in terms of toughness. Depending on the application of the alloy, high temperature toughness may be emphasized even though the high temperature creep strength may be somewhat reduced.
【０００５】[0005]
【発明が解決しようとする課題】本発明は、メカニカル
アロイングによりＣｒ基金属のマトリックス中に微細な
Ｙ2Ｏ3を略均一に分散させた粉末の焼結合金において、
高温靱性の改善を図ることを目的とする。DISCLOSURE OF THE INVENTION The present invention provides a powdered sintered alloy in which fine Y 2 O 3 is dispersed substantially uniformly in a matrix of Cr-based metal by mechanical alloying.
The purpose is to improve high temperature toughness.
【０００６】[0006]
【課題を解決するための手段】本発明の焼結合金は、メ
カニカルアロイングによって金属のマトリックス中に微
細なＹ2Ｏ3とＴａ2Ｏ5を略均一に分散させた粉末を原料
として焼結するものであって、前記金属は、(a)実質的
にＣｒからなる金属、又は、(b)Ｆｅ：20％以下、及び
残部実質的にＣｒからなる金属、又は、(c)Ａｌ、Ｍ
ｏ、Ｗ、Ｎｂ、Ｔａ、Ｈｆ及びＡｌ−Ｔｉから構成され
る群から選択される少なくとも一種が合計量で10％以
下、及び残部実質的にＣｒからなる金属、又は、(d)Ｆ
ｅ：20％以下、Ａｌ、Ｍｏ、Ｗ、Ｎｂ、Ｔａ、Ｈｆ及び
Ａｌ−Ｔｉから構成される群から選択される少なくとも
一種が合計量で10％以下、及び残部実質的にＣｒからな
る金属であり、Ｙ2Ｏ3は0.2〜2.0％(重量％、以下同
じ)、Ｔａ2Ｏ5は0.05〜2.0％含まれている。The sintered alloy of the present invention is obtained by sintering a powder, in which fine Y 2 O 3 and Ta 2 O 5 are dispersed substantially uniformly in a metal matrix by mechanical alloying. The metal is (a) a metal substantially composed of Cr, or (b) Fe: 20% or less, and the remaining metal substantially composed of Cr, or (c) Al, M.
o, W, Nb, Ta, Hf and at least one kind selected from the group consisting of Al-Ti in a total amount of 10% or less, and the balance consisting essentially of Cr, or (d) F
e: 20% or less, at least one selected from the group consisting of Al, Mo, W, Nb, Ta, Hf and Al-Ti in a total amount of 10% or less, and the balance being a metal substantially consisting of Cr. Y 2 O 3 is contained in an amount of 0.2 to 2.0% (weight%, the same applies hereinafter), and Ta 2 O 5 is included in an amount of 0.05 to 2.0%.
【０００７】Ｃｒ基金属のマトリックス中に分散した微
細なＴａ2Ｏ5は、焼結時に結晶粒の粗大化を抑制する働
きがある。この原料粉末から得られる焼結品は、金属マ
トリックスの結晶粒径が平均約10μm以下となり、非常
に微細な組織を有している。Fine Ta 2 O 5 dispersed in a matrix of Cr-based metal has a function of suppressing coarsening of crystal grains during sintering. The sintered product obtained from this raw material powder has an average crystal grain size of about 10 μm or less, and has a very fine structure.
【０００８】Ｔａ2Ｏ5の含有量は、焼結時における結晶
粒の十分な粗大化抑制作用を発揮させるために下限を0.
05重量％とする。一方、あまりに多く含有すると、高温
強度の低下が著しくなるので、上限を2.0重量％とす
る。なお、高温クリープ強度の低下をできるだけ小さく
抑え、かつ所望の高温靱性を得るのに望ましいＴａ2Ｏ5
の範囲は、0.1〜0.5％である。The content of Ta 2 O 5 has a lower limit of 0 in order to exert a sufficient effect of suppressing the coarsening of crystal grains during sintering.
05% by weight On the other hand, if the content is too large, the high temperature strength will be significantly reduced, so the upper limit is made 2.0% by weight. It should be noted that Ta 2 O 5 which is desirable to suppress the decrease in high temperature creep strength as small as possible and to obtain a desired high temperature toughness
The range is 0.1 to 0.5%.
【０００９】基地金属として、実質的にＣｒからなる金
属、又はＦｅ：20％以下、及び残部実質的にＣｒからな
る金属、又はＡｌ、Ｍｏ、Ｗ、Ｎｂ、Ｔａ、Ｈｆ及びＡ
ｌ−Ｔｉから構成される群から選択される少なくとも一
種が合計量で10％以下、及び残部実質的にＣｒからなる
金属、又はＦｅ：20％以下、Ａｌ、Ｍｏ、Ｗ、Ｎｂ、Ｔ
ａ、Ｈｆ及びＡｌ−Ｔｉから構成される群から選択され
る少なくとも一種が合計量で10％以下、及び残部実質的
にＣｒからなる金属を使用するのは、約1300℃の高温で
の使用において、所望の耐酸化性及び高温強度を得るた
めに最適だからである。また、Ｙ2Ｏ3を0.2〜2.0重量％
含有させるのは、0.2％よりも少ないとＹ2Ｏ3の微細分
散による強度向上効果が認められないからであり、2.0
％を超えて含有しても効果は飽和するだけでなく、高温
での使用中にＹ2Ｏ3粒子が凝集して粗大化する虞れもで
てくるからである。As a base metal, a metal consisting essentially of Cr, or Fe: 20% or less, and the balance consisting essentially of Cr, or Al, Mo, W, Nb, Ta, Hf and A.
The total amount of at least one selected from the group consisting of 1-Ti is 10% or less, and the balance is a metal substantially consisting of Cr, or Fe: 20% or less, Al, Mo, W, Nb, T.
a, Hf and at least one selected from the group consisting of Al-Ti in a total amount of 10% or less, and the balance consisting essentially of Cr is used at a high temperature of about 1300 ° C. This is because it is optimal for obtaining desired oxidation resistance and high temperature strength. In addition, Y 2 O 3 is 0.2 to 2.0% by weight.
If the content is less than 0.2%, the effect of improving the strength due to fine dispersion of Y 2 O 3 is not recognized,
This is because the effect is not only saturated when the content exceeds%, but also the Y 2 O 3 particles may aggregate and become coarse during use at high temperature.
【００１０】[0010]
【作用】基地金属の結晶粒が微細化されると、粒界すべ
りが発生しやすくなる結果、合金の変形能が大きくなっ
て靱性が向上する。When the crystal grains of the base metal are made finer, grain boundary slip easily occurs, and as a result, the deformability of the alloy increases and the toughness improves.
【００１１】[0011]
【実施例】Ｃｒ粉末、Ｆｅ粉末、Ｙ2Ｏ3粉末及びＴａ2
Ｏ5粉末を高エネルギー型ボールミル(アトライタ装置)
に投入し、メカニカルアロイング処理を行なって、各種
の粉末を作製した。各供試粉末の成分を表１に示す。各
供試粉末を鋼缶に充填し、脱気密封の後、ＨＩＰ焼結を
行ない、直径30mm×長さ50mmの焼結品を得た。なお、Ｈ
ＩＰは、圧力媒体としてアルゴンガスを用い、温度1250
℃×圧力118MPa×2時間の条件にて実施した。Examples Cr powder, Fe powder, Y 2 O 3 powder and Ta 2
High energy type ball mill for O 5 powder (attritor device)
, And mechanically alloyed to prepare various powders. The components of each test powder are shown in Table 1. Each test powder was filled in a steel can, and after degassing and sealing, HIP sintering was performed to obtain a sintered product having a diameter of 30 mm and a length of 50 mm. In addition, H
IP uses argon gas as a pressure medium and has a temperature of 1250.
It was carried out under the conditions of ℃ × pressure 118 MPa × 2 hours.
【００１２】高温圧縮試験 得られた供試焼結品について高温繰返し圧縮試験を行な
い、その変形量により高温クリープ強度を調べた。試験
は、1350℃の電気炉の中で、ラムの昇降により、圧縮荷
重0.5kgf/mm2を反復負荷して行なった。荷重反復パター
ンは、圧縮荷重0.5kgf/mm2の負荷を5秒間、無負荷5秒間
(負荷状態から無負荷状態への移行1秒、無負荷状態3
秒、無負荷状態から負荷状態への移行1秒)の10秒サイク
ルにて、焼結品に104回圧縮荷重を作用させて変形量(単
位：％)を調べた。試験結果を表１に示す。なお、変形
量は、試験前の長さをＬ1、試験後の長さをＬ2としたと
き、次式により求めた。 圧縮変形量(％) ＝ (Ｌ1−Ｌ2)／Ｌ1 × 100 High-temperature compression test A high-temperature cyclic compression test was conducted on the obtained test sintered product, and the high-temperature creep strength was examined by the deformation amount. The test was performed in an electric furnace at 1350 ° C. by repeatedly raising and lowering a ram and applying a compressive load of 0.5 kgf / mm 2 . Repeated load pattern is a compression load of 0.5 kgf / mm 2 for 5 seconds and no load for 5 seconds.
(Transition from loaded state to unloaded state 1 second, unloaded state 3
The amount of deformation (unit:%) was examined by applying a compressive load to the sintered product 10 4 times in a 10-second cycle of 1 second from the no-load state to the loaded state). Table 1 shows the test results. The amount of deformation was determined by the following equation, where L1 is the length before the test and L2 is the length after the test. Compressive deformation amount (%) = (L1-L2) / L1 x 100
【００１３】高温曲げ試験 各供試焼結品について、高温曲げ試験を行ない、靱性を
調べた。曲げ試験はJIS R 1601に準拠し、3×4×50mmの
試験片について、スパン距離30mm、試験温度1300℃の条
件にて実施した。試験結果を表１に示す。なお、表１で
は、曲げ試験中の最大曲げ荷重と、破断に至るまでのた
わみ量を記載しており、靱性はこれらにより評価する。 High Temperature Bending Test Each sample sintered product was subjected to a high temperature bending test to examine its toughness. The bending test was carried out in accordance with JIS R 1601 on a test piece of 3 × 4 × 50 mm under conditions of a span distance of 30 mm and a test temperature of 1300 ° C. Table 1 shows the test results. In addition, in Table 1, the maximum bending load during the bending test and the amount of deflection until fracture are described, and the toughness is evaluated by these.
【００１４】[0014]
【表１】 [Table 1]
【００１５】供試No.１はＴａ2Ｏ5を含んでいないた
め、高温圧縮試験による変形量は小さいが、120MPaの曲
げ荷重により0.2mm撓んだだけで破断に至っている。供
試No.２はＴａ2Ｏ5を含んでいるが、その含有量は0.01
％と少ないため、No.１の実施例とほぼ同じ結果となっ
ている。供試No.３はＴａ2Ｏ5を0.05％含有しており、
高温圧縮試験における変形量は1.7％と増加して高温ク
リープ強度は僅かに低下するが、高温曲げ試験では、最
大曲げ荷重112MPaにおける撓み量が1.0mmに増加してお
り、Ｔａ2Ｏ5の結晶粒微細効果が認められる。供試No.
４〜No.８を参照すると、Ｔａ2Ｏ5の含有量が増加する
につれて、高温圧縮試験における変形量は大きくなり、
高温クリープ強度は低下する。高温曲げ試験における撓
み量は全て3.0mmであるが、これは撓み量が3.0mmに達し
た時点で試験を中止したためであり、Ｔａ2Ｏ5の含有量
が増加するにつれて、3.0mmの撓み量に達する最大曲げ
荷重が小さくなっている。最大曲げ荷重が小さくなるほ
ど伸びを生じ易いことを意味するから、Ｔａ2Ｏ5の含有
量が増加するにつれて靱性が向上することを表わしてい
る。これらの結果から、微細なＴａ2Ｏ5の基地金属への
分散による結晶粒微細効果が認められる。Since the sample No. 1 does not contain Ta 2 O 5 , the deformation amount by the high temperature compression test is small, but the sample is fractured only by bending 0.2 mm under the bending load of 120 MPa. Test No. 2 contains Ta 2 O 5 , but its content is 0.01
%, It is almost the same as the No. 1 embodiment. Test No. 3 contains 0.05% Ta 2 O 5 ,
Although the high-temperature creep strength deformation amount is increased to 1.7% in the high-temperature compression test decreases slightly at high temperatures bending test, the amount of deflection at the maximum bending load 112MPa is increasing to 1.0 mm, the crystal of Ta 2 O 5 Fine grain effect is observed. Sample No.
4 to No. 8, as the content of Ta 2 O 5 increases, the amount of deformation in the high temperature compression test increases,
The high temperature creep strength decreases. The bending amount in the high temperature bending test was 3.0 mm in all, but this is because the test was stopped when the bending amount reached 3.0 mm, and the bending amount of 3.0 mm increased as the content of Ta 2 O 5 increased. The maximum bending load to reach is smaller. Since it means that the smaller the maximum bending load is, the more easily the elongation is caused, which means that the toughness is improved as the content of Ta 2 O 5 is increased. From these results, the grain refinement effect due to the dispersion of fine Ta 2 O 5 in the base metal is recognized.
【００１６】なお、高温クリープ強度に関しては、前記
繰返し圧縮試験における変形量が4.0％を超えると実用
上不都合の生じる虞れがあるため、Ｔａ2Ｏ5の含有量は
2.0％を上限とする。上記の結果より、高温クリープ強
度の低下をできるだけ小さい範囲に抑え、かつ優れた高
温靱性を具備させるには、Ｔａ2Ｏ5の添加量は0.1〜0.5
％が望ましい。Regarding the high temperature creep strength, if the amount of deformation in the above-mentioned repeated compression test exceeds 4.0%, there is a possibility that practical inconvenience may occur, so the content of Ta 2 O 5 is
The upper limit is 2.0%. From the above results, the amount of Ta 2 O 5 added is 0.1 to 0.5 in order to suppress the decrease in high temperature creep strength to the smallest possible range and to have excellent high temperature toughness.
% Is desirable.
【００１７】[0017]
【発明の効果】本発明にかかる焼結品は、所定の高温圧
縮クリープ強度を具備し、約1300℃以上の高温における
靱性にすぐれている。従って、これら両特性が重要な用
途、例えばウオーキングビームコンベヤー式加熱炉のス
キッドボタン等に好適である。The sintered product according to the present invention has a predetermined high temperature compression creep strength and is excellent in toughness at a high temperature of about 1300 ° C. or higher. Therefore, both of these characteristics are suitable for applications in which the above-mentioned characteristics are important, for example, a skid button of a walking beam conveyor type heating furnace.
Claims (1)
トリックス中に微細なＹ2Ｏ3とＴａ2Ｏ5を略均一に分散
させた粉末の焼結合金であり、前記金属は、(a)実質的
にＣｒからなる金属、又は(b)Ｆｅ：20％以下、及び残
部実質的にＣｒからなる金属、又は(c)Ａｌ、Ｍｏ、
Ｗ、Ｎｂ、Ｔａ、Ｈｆ及びＡｌ−Ｔｉから構成される群
から選択される少なくとも一種が合計量で10％以下、及
び残部実質的にＣｒからなる金属、又は(d)Ｆｅ：20％
以下、Ａｌ、Ｍｏ、Ｗ、Ｎｂ、Ｔａ、Ｈｆ及びＡｌ−Ｔ
ｉから構成される群から選択される少なくとも一種が合
計量で10％以下、及び残部実質的にＣｒからなる金属、
であって、Ｙ2Ｏ3は0.2〜2.0％(重量％、以下同じ)、Ｔ
ａ2Ｏ5は0.05〜2.0％含まれている、高温靱性にすぐれ
る酸化物分散強化耐熱焼結合金。1. A powdered sintered alloy in which fine Y 2 O 3 and Ta 2 O 5 are substantially uniformly dispersed in a metal matrix by mechanical alloying, the metal being (a) substantially Metal consisting of Cr, or (b) Fe: 20% or less, and the balance consisting essentially of Cr, or (c) Al, Mo,
The total amount of at least one selected from the group consisting of W, Nb, Ta, Hf and Al-Ti is 10% or less, and the balance is a metal consisting essentially of Cr, or (d) Fe: 20%.
Hereinafter, Al, Mo, W, Nb, Ta, Hf and Al-T
a metal in which at least one selected from the group consisting of i is 10% or less in total amount, and the balance is substantially Cr.
And Y 2 O 3 is 0.2 to 2.0% (wt%, the same applies hereinafter), T
a 2 O 5 is contained from 0.05 to 2.0%, oxide dispersion strengthened heat sintered alloy having excellent high-temperature toughness.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18007294A JPH0841578A (en) | 1994-08-01 | 1994-08-01 | Oxide dispersion reinforced heat resistant sintered alloy excellent in toughness at high temperature |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18007294A JPH0841578A (en) | 1994-08-01 | 1994-08-01 | Oxide dispersion reinforced heat resistant sintered alloy excellent in toughness at high temperature |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0841578A true JPH0841578A (en) | 1996-02-13 |
Family
ID=16076975
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18007294A Pending JPH0841578A (en) | 1994-08-01 | 1994-08-01 | Oxide dispersion reinforced heat resistant sintered alloy excellent in toughness at high temperature |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0841578A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999000529A1 (en) * | 1997-06-30 | 1999-01-07 | Praxair S.T. Technology, Inc. | Metallic chromium-tantalum oxide composition, sputtering targets and magnetic recording media |
-
1994
- 1994-08-01 JP JP18007294A patent/JPH0841578A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999000529A1 (en) * | 1997-06-30 | 1999-01-07 | Praxair S.T. Technology, Inc. | Metallic chromium-tantalum oxide composition, sputtering targets and magnetic recording media |
| US5989673A (en) * | 1997-06-30 | 1999-11-23 | Sony Corporation | Caromium-tantalum oxides (Cr-TaOx), sputtering targets and thin film seedlayer/sublayers for thin film magnetic recording media |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100236151B1 (en) | Co-cr-mo powder metallurgy articles and process for their manufacture | |
| US7767138B2 (en) | Process for the production of a molybdenum alloy | |
| JPH0747793B2 (en) | Oxide dispersion strengthened heat resistant sintered alloy | |
| JP3271040B2 (en) | Molybdenum alloy and method for producing the same | |
| US6368376B2 (en) | Process for making oxide dispersion-strengthened tungsten heavy alloy by mechanical alloying | |
| US3052538A (en) | Titanium base alloys | |
| US7226492B2 (en) | High-powder tungsten-based sintered alloy | |
| JPH0841578A (en) | Oxide dispersion reinforced heat resistant sintered alloy excellent in toughness at high temperature | |
| JPH0841577A (en) | Oxide dispersion reinforced heat resistant sintered alloy excellent in toughness at high temperature | |
| JPH0633166A (en) | Manufacture of oxide dispersion-strengthened heat resistant alloy sintered compact | |
| JPH0741882A (en) | Production of sintered titanium alloy | |
| CA2473493A1 (en) | Stabilized grain size refractory metal powder metallurgy mill products | |
| JPH0250172B2 (en) | ||
| KR100197152B1 (en) | Method for sintering heavy alloy of w-ni-mn system | |
| JPH08193201A (en) | Production of yttrium oxide-dispersed chromium-base alloy | |
| JP2001152208A (en) | OXIDE DISPERSION STRENGTHENED TYPE Ni BASE ALLOY WIRE AND PRODUCING METHOD THEREFOR | |
| Ruano et al. | Room temperature strength and ductility of rapidly solidified white cast irons | |
| KR20090050732A (en) | Method for fabricating oxide dispersion strengthened tungsten heavy alloy by two-step mechanical alloying process | |
| JP2932653B2 (en) | Skid rail for heating furnace and method of manufacturing the same | |
| JPH0881730A (en) | Cr-based alloy strengthened by dispersing oxide and excellent in high-temperature compressive strength | |
| Huang et al. | Ir-based refractory superalloys by pulse electric current sintering (PECS) process (II prealloyed powder) | |
| Sikora et al. | Dispersion strengthened nickel-yttria sheet alloy produced from comminuted powders | |
| JPH0841562A (en) | Production of chromum-base oxide dispersion reinforced sintered alloy | |
| JPH08193202A (en) | Production of yttrium oxide-dispersed chromium-base alloy powder | |
| JP3628748B2 (en) | Manufacturing method of carbide dispersion sintered alloy |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20001003 |