JPH04280946A - Duplex stainless steel excellent in corrosion resistance - Google Patents

Duplex stainless steel excellent in corrosion resistance

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Publication number
JPH04280946A
JPH04280946A JP41893190A JP41893190A JPH04280946A JP H04280946 A JPH04280946 A JP H04280946A JP 41893190 A JP41893190 A JP 41893190A JP 41893190 A JP41893190 A JP 41893190A JP H04280946 A JPH04280946 A JP H04280946A
Authority
JP
Japan
Prior art keywords
duplex stainless
stainless steel
pitting
resistance
corrosion
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
JP41893190A
Other languages
Japanese (ja)
Inventor
Tsuneaki Kobayashi
小林 経明
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.)
Nippon Steel Corp
Original Assignee
Sumitomo Metal Industries 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 Sumitomo Metal Industries Ltd filed Critical Sumitomo Metal Industries Ltd
Priority to JP41893190A priority Critical patent/JPH04280946A/en
Publication of JPH04280946A publication Critical patent/JPH04280946A/en
Pending legal-status Critical Current

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Abstract

PURPOSE:To improve the pitting resistance of a duplex stainless steel without adding Cu and Co. CONSTITUTION:In a duplex stainless steel of a component system containing, by weight ratio, <=0.008% C, 0.2-2.0% Si, 0.2-2.0% Mn, 19-<26% Cr, 3.0-8.0% Ni, 1.0-5.0% Mo, and 0.05-0.3% N, the value of IN=Cr+3Mo+16N is regulated to 34.5%. By this method, >=34.5% IN can be provided and pitting resistance can be remarkably improved. Further, because the necessity of the addition of Cu and Co is obviated, cost reduction can be attained and also superior hot workability can be provided.

Description

【発明の詳細な説明】[Detailed description of the invention]

【0001】0001

【産業上の利用分野】本発明は、油井管、油送管等に使
用される二相ステンレス鋼に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to duplex stainless steel used for oil country tubular goods, oil transmission pipes, etc.

【0002】0002

【従来の技術】フェライト相とオーステナイト相の2相
組織を有する二相ステンレス鋼は、耐食性とりわけ微量
のH2 Sを含むCO2 環境下での耐食性に優れ、且
つ強度、延性等の機械的性質に優れることから、油井管
、油送管の主要素材とされている。油井管、油送管に使
用される代表的な二相ステンレス鋼としては、例えばA
STM  A790  UNS−S31803に規定さ
れた22%Cr二相ステンレス鋼がある。しかし、近時
の採掘条件の悪化に伴い、油井管の使用環境は著しく過
酷になり、以前にも増して厳しい仕様が油井管に要求さ
れるようになった。例えば、ASTM  G48に規定
された10%FeCl3 ・ 6H2 O(30℃)に
よるピッティングテストはその一つであり、上記規格鋼
はこのテストをクリアし得ないとされている。そこで、
最近になってこのテストに耐え得る22%Cr二相ステ
ンレス鋼の開発が始められ、例えば特公平2−3234
3号公報にはCu、Coの添加によって耐ピッティング
性を高めた22%Cr二相ステンレス鋼が開示されてい
る。
[Prior Art] Duplex stainless steel, which has a two-phase structure of a ferrite phase and an austenite phase, has excellent corrosion resistance, especially in a CO2 environment containing a trace amount of H2S, and has excellent mechanical properties such as strength and ductility. For this reason, it is considered the main material for oil country tubular goods and oil transmission pipes. Typical duplex stainless steels used for oil country tubular goods and oil transmission pipes include A
There is a 22% Cr duplex stainless steel specified in STM A790 UNS-S31803. However, with recent deterioration in mining conditions, the environment in which OCTGs are used has become extremely harsh, and OCTGs are now required to meet even more stringent specifications than ever before. For example, the pitting test using 10% FeCl3.6H2O (30° C.) specified in ASTM G48 is one such test, and it is said that the above-mentioned standard steel cannot pass this test. Therefore,
Recently, development of 22% Cr duplex stainless steel that can withstand this test has begun, for example, Japanese Patent Publication No. 2-3234.
Publication No. 3 discloses a 22% Cr duplex stainless steel whose pitting resistance is improved by adding Cu and Co.

【0003】0003

【発明が解決しようとする課題】ここに開示された22
%Cr二相ステンレス鋼は、ASTM  G48に規定
されたピッティングテストをクリアする優れた耐ピッテ
ィング性を有するものの、耐ピッティング性改善のため
にCu、Coを添加しており、合金添加コストが上昇す
るという問題がある。特に、Coは高価な元素であり、
その使用は製品価格の上昇を招く。また、Cu、Coの
何れもが、熱間加工性を低下させる原因になる。
[Problem to be solved by the invention] 22 disclosed herein
%Cr duplex stainless steel has excellent pitting resistance that passes the pitting test specified by ASTM G48, but Cu and Co are added to improve pitting resistance, reducing the cost of alloy addition. There is a problem with the increase in In particular, Co is an expensive element,
Its use leads to increased product prices. Further, both Cu and Co cause deterioration in hot workability.

【0004】本発明の目的は、耐ピッティング性に優れ
、しかも低コストで熱間加工性に優れた二相ステンレス
鋼を提供することにある。
An object of the present invention is to provide a duplex stainless steel that has excellent pitting resistance, low cost, and excellent hot workability.

【0005】[0005]

【課題を解決するための手段】ASTM  A790 
 UNS−S31803に規定された成分組成は、重量
比でC:0.030%以下、Si:1.00%以下、M
n:2.00%以下、P:0.030%以下、S:0.
010%以下、Ni:4.50〜6.50%、Cr:2
1.00〜23.00%、Mo:2.50〜3.50%
、N:0.08〜0.20%というものである。この2
2%Cr二相ステンレス鋼は、前述したように、AST
M  G48に規定された10%FeCl3 ・6H2
 O(30℃)によるピッティングテストをクリアし得
ないとされていた。しかし、本発明者らの調査によれば
、このテストをクリアし得ない二相ステンレス鋼は、各
成分が規格範囲の中心狙いで設計されているものであり
、各成分、とりわけCr、Mo、Nを規格範囲の上限狙
いで設計したものについては、Cu、Coを特に添加し
なくても、これらを添加した場合に匹敵する耐ピッティ
ング性の得られることが明らかになった。
[Means for solving the problem] ASTM A790
The component composition specified by UNS-S31803 is C: 0.030% or less, Si: 1.00% or less, M
n: 2.00% or less, P: 0.030% or less, S: 0.
010% or less, Ni: 4.50 to 6.50%, Cr: 2
1.00-23.00%, Mo: 2.50-3.50%
, N: 0.08 to 0.20%. This 2
The 2% Cr duplex stainless steel is, as mentioned above, AST
10% FeCl3 ・6H2 specified in MG48
It was said that it could not pass the pitting test using O (30°C). However, according to the research conducted by the present inventors, duplex stainless steels that cannot pass this test are designed with each component in the center of the standard range, and each component, especially Cr, Mo, It has become clear that for those designed with N in mind at the upper limit of the standard range, pitting resistance comparable to that achieved when Cu and Co are added can be obtained even without the addition of Cu or Co.

【0006】各成分が規格範囲の中心狙いで設計された
従来の22%Cr二相ステンレス鋼における成分分布を
表1のCase1に示し、その場合のピッティングイン
デッスクPI=Cr+3Mo+16Nの分布を図2のC
ase1に示す。このような成分分布の22%Cr二相
ステンレス鋼は、ASTM  G48に規定された例え
ば10%FeCl3 ・6H2 O(30℃)によるピ
ッティングテストをクリアできない。しかし、Cr、M
o、Nを表1及び図2のCase2に示すように規格成
分範囲の上限狙いとすると、Cu、Coを添加しなくて
も、Cu、Coを添加した場合に匹敵する耐ピッティン
グ性が得られるのである。
The component distribution in a conventional 22% Cr duplex stainless steel in which each component is designed to aim at the center of the standard range is shown in Case 1 of Table 1, and the distribution of the pitting index PI=Cr+3Mo+16N in that case is shown in FIG. C of
It is shown in ase1. A 22% Cr duplex stainless steel having such a component distribution cannot pass a pitting test using, for example, 10% FeCl3.6H2O (30° C.) specified in ASTM G48. However, Cr, M
If o and N are aimed at the upper limits of the standard component ranges as shown in Table 1 and Case 2 in Figure 2, pitting resistance comparable to the case of adding Cu and Co can be obtained even without adding Cu and Co. It will be done.

【0007】[0007]

【表1】[Table 1]

【0008】22%Cr二相ステンレス鋼に10%Fe
Cl3 ・6H2 O、30℃、24hrsのピッティ
ングテストを実施した場合の鋼中PIと腐食速度との関
係を図1に示す。PIが大きくなるほど、腐食速度が低
下し、PI≧34.5で腐食は皆無となる。また、表1
及び図2にCase2として示された22%Cr二相ス
テンレス鋼の機械的性質を図3及び図4に示すが、PI
の高い22%Cr二相ステンレス鋼は機械的性質も良好
である。更に、Case2のフェライト相分布を図5に
示し、Case2の鋼管に自動GTAWで周溶接を行っ
たときの溶接部硬度を図6に示す。耐ピッティング性に
優れた高PI鋼は、組織および溶接性も問題のないこと
が確認された。図7に溶接部硬度の測定点を示す。
22%Cr duplex stainless steel with 10%Fe
Figure 1 shows the relationship between the PI in steel and the corrosion rate when a pitting test was conducted using Cl3.6H2O at 30°C for 24 hours. As PI increases, the corrosion rate decreases, and when PI≧34.5, there is no corrosion. Also, Table 1
The mechanical properties of the 22% Cr duplex stainless steel shown as Case 2 in Fig. 2 are shown in Figs. 3 and 4.
The high 22% Cr duplex stainless steel also has good mechanical properties. Furthermore, the ferrite phase distribution of Case 2 is shown in FIG. 5, and the weld hardness when circumferential welding is performed on the steel pipe of Case 2 by automatic GTAW is shown in FIG. It was confirmed that the high PI steel, which has excellent pitting resistance, has no problems in structure and weldability. Figure 7 shows the measurement points of weld hardness.

【0009】本発明は上記知見に基づきなされたもので
、重量比でC:0.08%以下、Si:0.2〜2.0
%、Mn:0.2〜2.0%、Cr:19%以上、26
%未満、Ni:3.0〜8.0%、Mo:1.0〜5.
0%、N:0.05〜0.3%、を含み、残部Feおよ
び不可避不純物からなり、且つCr+3Mo+16N≧
34.5%を満足することを特徴とする耐食性の優れた
二相ステンレス鋼を要旨とする。
The present invention was made based on the above knowledge, and the weight ratio of C: 0.08% or less, Si: 0.2 to 2.0%
%, Mn: 0.2 to 2.0%, Cr: 19% or more, 26
%, Ni: 3.0-8.0%, Mo: 1.0-5.
0%, N: 0.05 to 0.3%, the balance consists of Fe and inevitable impurities, and Cr+3Mo+16N≧
The main feature is a duplex stainless steel with excellent corrosion resistance that satisfies 34.5%.

【0010】0010

【作用】本発明の二相ステンレス鋼における成分限定理
由は以下のとおりである。
[Operation] The reasons for limiting the components in the duplex stainless steel of the present invention are as follows.

【0011】Cはオーステナイト生成元素であり、且つ
強度の向上に著効を有するが、含有量が多すぎると、ク
ロム炭化物が析出し易くなり、炭化物近傍におけるCr
濃度が減少する結果、孔食、すきま腐食、粒界腐食等の
局部腐食に対する抵抗性が低下し、且つ耐応力腐食割れ
性の劣化をみる。このため、0.08%を上限とする。
C is an austenite-forming element and has a remarkable effect on improving strength, but if the content is too large, chromium carbide tends to precipitate, and Cr near the carbide
As a result of the decrease in concentration, resistance to localized corrosion such as pitting corrosion, crevice corrosion, and intergranular corrosion decreases, and stress corrosion cracking resistance deteriorates. Therefore, the upper limit is set at 0.08%.

【0012】Siは溶鋼の脱酸および鋳造性確保のため
、少なくとも0.2%を必要とする。しかし、多量の含
有は靱性を悪くし、且つ溶接性をも損なうので、2.0
%を上限とする。
[0012] At least 0.2% of Si is required for deoxidizing molten steel and ensuring castability. However, since a large amount of content deteriorates toughness and also impairs weldability, 2.0
The upper limit is %.

【0013】Mnは通常の脱酸・脱硫過程で、1.0%
程度含有されるもので、また鋼素地のオーステナイト相
の安定化に有効な元素である。このための含有量は2%
までで十分であり、それをこえる必要はない。よって、
0.2〜2.0%とする。
[0013] Mn is reduced to 1.0% in the normal deoxidation and desulfurization process.
It is an element that is effective in stabilizing the austenite phase of the steel matrix. The content for this is 2%
Up to this point is sufficient, and there is no need to go beyond that. Therefore,
The content should be 0.2 to 2.0%.

【0014】Crは耐食性、特に耐粒界腐食性の改善に
著効を有するとともに、耐応力腐食割れ向上に寄与する
。また、Crはフェライト相生成元素であり、二相組織
におけるフェライト相の形成により強度を高める。本発
明鋼では後記Ni量との相関関係で、19.0%以上の
Crを含有しないと、所要のフェライト量(面積率で3
0%以上)を確保しがたい。よって、耐食性とフェライ
ト量の点から、Cr量の下限を19.0%とする。一方
、Cr量があまり多くなると、鋼の靱性の著しい低下を
生じ、かつ鋳造時に硬脆なσ相が成長する。更に、Ni
量との相関関係からフェライト相量が70%を超え、二
相組織におけるオーステナイト相とのバランスを失し、
耐食性、就中孔食、すきま腐食に対する抵抗性を損なう
。 このため、Cr量は26%未満とする。
Cr has a remarkable effect on improving corrosion resistance, particularly intergranular corrosion resistance, and also contributes to improving stress corrosion cracking resistance. Further, Cr is a ferrite phase forming element, and increases strength by forming a ferrite phase in a two-phase structure. In the steel of the present invention, the required amount of ferrite (area ratio of 3
0% or more) is difficult to secure. Therefore, from the viewpoint of corrosion resistance and ferrite content, the lower limit of the Cr content is set to 19.0%. On the other hand, if the amount of Cr is too large, the toughness of the steel will be significantly reduced, and a hard and brittle σ phase will grow during casting. Furthermore, Ni
From the correlation with the amount, the amount of ferrite phase exceeds 70%, and the balance with the austenite phase in the two-phase structure is lost.
Impairs corrosion resistance, especially resistance to pitting and crevice corrosion. Therefore, the Cr content is set to less than 26%.

【0015】Niはオーステナイト相を安定化する元素
であり、鋼の靱性の向上をもたらす。また、耐食性の点
からも必要な元素である。含有量が3.0%に満たない
と、これらの効果が不足する。前記Cr量との関係から
、フェライト相量を70%以下にするためにも3.0%
以上の含有を必要とする。しかし、Niを多量に加えて
も、含有量の割に耐食性、機械的性質の向上効果は少な
く経済的に不利であるばかりか、二相組織におけるオー
ステナイト相が過剰になって二相の量的バランスを失う
。従って、Ni量は8.0%を上限とする。
[0015] Ni is an element that stabilizes the austenite phase and improves the toughness of steel. It is also a necessary element from the viewpoint of corrosion resistance. If the content is less than 3.0%, these effects will be insufficient. From the relationship with the Cr content, 3.0% is also required to reduce the ferrite phase content to 70% or less.
or more is required. However, even if a large amount of Ni is added, the effect of improving corrosion resistance and mechanical properties is small compared to the Ni content, which is economically disadvantageous. lose balance. Therefore, the upper limit of the Ni amount is 8.0%.

【0016】Moはステンレス鋼の耐食性の改善に大き
な効果を有する。ことに、孔食、すきま腐食抵抗性の改
善に著効を奏する。1.0%以上において、非酸化性酸
に対する耐食性、また塩化物を含む溶液中での孔食、粒
界腐食および応力腐食割れに対する抵抗性の顕著な向上
をみる。しかし、多量に加えると、耐食性の改善効果は
飽和し、かつσ相の析出による鋳造時の脆化が著しくな
るので、5.0%を上限とする。
Mo has a great effect on improving the corrosion resistance of stainless steel. It is particularly effective in improving resistance to pitting corrosion and crevice corrosion. At 1.0% or more, significant improvements in corrosion resistance to non-oxidizing acids, as well as resistance to pitting corrosion, intergranular corrosion and stress corrosion cracking in chloride-containing solutions are observed. However, if added in a large amount, the effect of improving corrosion resistance will be saturated and embrittlement during casting due to precipitation of σ phase will become significant, so the upper limit is set at 5.0%.

【0017】Nは通常有害な不純物元素として扱われる
が、本発明鋼では強度向上および耐食性改善を目的とし
て0.05〜0.3%の範囲内で添加される。即ち、N
はCと同じく強力なオーステナイト生成元素であり、且
つ侵入型固溶元素であるため、鋼基地の結晶格子に強い
格子歪みをもたらし、強度向上に顕著に寄与する。また
、Nは二相組織において、Cr、Ni、Mo等の主要元
素のフェライト相並びにオーステナイト相への分配率に
影響を与え、ことに耐食性に寄与する元素Cr、Moな
どをオーステナイト相へ高濃度で分配することにより二
相ステンレス鋼の耐食性、就中すきま腐食や孔食などの
局部腐食に対する抵抗性を高める。特に本発明鋼のよう
に、Cr及びMo濃度が高く、そのフェライト相/オー
ステナイト相への分配率の差が顕著な、言い換えると偏
析の度合いの大きい合金系においては、Nの添加はこれ
らの耐食性元素をより高濃度でオーステナイト相に分配
しようとする作用を有し、従ってそれによる耐食性、と
くに局部腐食抵抗性の向上も顕著にあらわれる。この効
果を十分に発揮させるためにN量は少なくとも0.05
%を必要とする。N量の増加に伴って効果も増すが、0
.3%をこえると窒化物として析出し、却って耐食性を
悪くする。Nは固溶状態にあってこそ強度向上および耐
食性の改善に著効を奏するのである。従って、N量は0
.05〜0.3%とする。
Although N is normally treated as a harmful impurity element, it is added in the range of 0.05 to 0.3% in the steel of the present invention for the purpose of improving strength and corrosion resistance. That is, N
Since C is a strong austenite-forming element like C and is an interstitial solid solution element, it causes strong lattice distortion in the crystal lattice of the steel base, and significantly contributes to improving the strength. In addition, in a two-phase structure, N influences the distribution ratio of major elements such as Cr, Ni, and Mo to the ferrite phase and austenite phase, and in particular, it increases the concentration of elements such as Cr and Mo that contribute to corrosion resistance into the austenite phase. This distribution improves the corrosion resistance of duplex stainless steel, especially its resistance to localized corrosion such as crevice corrosion and pitting corrosion. In particular, in alloy systems like the steel of the present invention, which have high Cr and Mo concentrations and a significant difference in their distribution ratio between the ferrite phase and the austenite phase, in other words, a high degree of segregation, the addition of N can improve the corrosion resistance of these. It has the effect of distributing elements to the austenite phase at a higher concentration, and therefore corrosion resistance, especially local corrosion resistance, is significantly improved. In order to fully exhibit this effect, the amount of N is at least 0.05
% is required. The effect increases as the amount of N increases, but 0
.. If it exceeds 3%, it will precipitate as nitrides, which will actually worsen the corrosion resistance. N has a significant effect on improving strength and corrosion resistance only when it is in a solid solution state. Therefore, the amount of N is 0
.. 05 to 0.3%.

【0018】Cr+3Mo+16N(PI)は、耐ピッ
ティング性を左右するCr,Mo,Nの各元素に各々係
数をかけて耐ピッティング性をあらわすインデックスで
ある。これらの係数は、Rockel(M.B.Roc
kel ACHEMA CONFERENCE,FRA
NKFURT,1979) の提唱した式Cr+3Mo
12Nの項を加えたもので、Nの係数は経験的に16と
したものである。このピッティングインデックス(PI
)は、大きい程その材料の孔食電位が高くなるが、例え
ば、10%FeCl3 ,6H2 O,30℃,24H
rsの腐食テスト環境でピッティングをおこさないため
には、その材料のピッティングインデックスの最少値は
実験的に34.5である。
Cr+3Mo+16N (PI) is an index representing the pitting resistance by multiplying each of the elements Cr, Mo, and N, which influence the pitting resistance, by a coefficient. These coefficients are calculated by Rockel (M.B.Roc
kel ACHEMA CONFERENCE,FRA
NKFURT, 1979) proposed the formula Cr+3Mo
12N terms are added, and the coefficient of N is empirically set to 16. This pitting index (PI
), the higher the pitting potential of the material, but for example, 10%FeCl3, 6H2O, 30℃, 24H
Experimentally, the minimum pitting index for the material is 34.5 in order to avoid pitting in the RS corrosion test environment.

【0019】[0019]

【実施例】表2に成分を示す10種類の二相ステンレス
鋼1〜10に10%FeCl3 ・6H2 O、24h
rsのピッティングテストを実施した。テスト温度は2
5℃と30℃の2種類とした。試験片の形状を図8に示
す。 ピッティングテストの結果と機械的特性を調査した結果
を表3に示す。表3から明らかなように、本発明鋼はい
ずれも上記ピッティングテストをクリアし、機械的性質
および熱間加工性も優れる。
[Example] 10 types of duplex stainless steels 1 to 10 whose components are shown in Table 2 were mixed with 10% FeCl3 6H2 O for 24 hours.
A pitting test was conducted on rs. The test temperature is 2
There were two types: 5°C and 30°C. The shape of the test piece is shown in FIG. Table 3 shows the results of the pitting test and the results of investigating the mechanical properties. As is clear from Table 3, all of the steels of the present invention cleared the above pitting test and had excellent mechanical properties and hot workability.

【0020】[0020]

【表2】[Table 2]

【0021】[0021]

【表3】[Table 3]

【0021】[0021]

【発明の効果】本発明の二相ステンレス鋼は、耐ピッテ
ィング性に優れ、しかも、Cu、Coを使用しないので
、熱間加工性が良好で経済性も良い。
[Effects of the Invention] The duplex stainless steel of the present invention has excellent pitting resistance, and since Cu and Co are not used, it has good hot workability and is economical.

【図面の簡単な説明】[Brief explanation of the drawing]

図1 PIとピッティングテストにおける腐食速度との関係を
示すグラフである。 図2 従来鋼および耐ピッティング性に優れた鋼におけるPI
分布を示すグラフである。 図3 耐ピッティング性に優れた高PI鋼の引張性能を示すグ
ラフである。 図4 耐ピッティング性に優れた高PI鋼の硬度を示すグラフ
である。 図5 耐ピッティング性に優れた高PI鋼のフェライト量を示
すグラフである。 図6 耐ピッティング性に優れた高PI鋼からなる鋼管の周溶
接部の硬度を示すグラフである。 図7 周溶接部の硬度測定点を示す概略図である。 図8 ピッティングテストに使用した試験片の形状を示す概略
図である。
FIG. 1 is a graph showing the relationship between PI and corrosion rate in a pitting test. Figure 2 PI of conventional steel and steel with excellent pitting resistance
It is a graph showing distribution. Figure 3 is a graph showing the tensile performance of high PI steel with excellent pitting resistance. Figure 4 is a graph showing the hardness of high PI steel with excellent pitting resistance. FIG. 5 is a graph showing the amount of ferrite in high PI steel with excellent pitting resistance. FIG. 6 is a graph showing the hardness of the circumferential weld of a steel pipe made of high PI steel with excellent pitting resistance. FIG. 7 is a schematic diagram showing the hardness measurement points of the circumferential weld. FIG. 8 is a schematic diagram showing the shape of a test piece used in a pitting test.

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】  重量比でC:0.08%以下、Si:
0.2〜2.0%、Mn:0.2〜2.0%、Cr:1
9%以上、26%未満、Ni:3.0〜8.0%、Mo
:1.0〜5.0%、N:0.05〜0.3%、を含み
、残部Feおよび不可避不純物からなり、且つCr+3
Mo+16N≧34.5%を満足することを特徴とする
耐食性の優れた二相ステンレス鋼。
[Claim 1] C: 0.08% or less, Si:
0.2-2.0%, Mn: 0.2-2.0%, Cr: 1
9% or more, less than 26%, Ni: 3.0-8.0%, Mo
: 1.0 to 5.0%, N: 0.05 to 0.3%, the balance consists of Fe and inevitable impurities, and Cr+3
Duplex stainless steel with excellent corrosion resistance, characterized by satisfying Mo+16N≧34.5%.
JP41893190A 1990-12-28 1990-12-28 Duplex stainless steel excellent in corrosion resistance Pending JPH04280946A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP41893190A JPH04280946A (en) 1990-12-28 1990-12-28 Duplex stainless steel excellent in corrosion resistance

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP41893190A JPH04280946A (en) 1990-12-28 1990-12-28 Duplex stainless steel excellent in corrosion resistance

Publications (1)

Publication Number Publication Date
JPH04280946A true JPH04280946A (en) 1992-10-06

Family

ID=18526681

Family Applications (1)

Application Number Title Priority Date Filing Date
JP41893190A Pending JPH04280946A (en) 1990-12-28 1990-12-28 Duplex stainless steel excellent in corrosion resistance

Country Status (1)

Country Link
JP (1) JPH04280946A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1995341A1 (en) * 2007-03-26 2008-11-26 Sumitomo Metal Industries Limited Oil well pipe for expansion in well and two-phase stainless steel for use as oil well pipe for expansion
JP2012149309A (en) * 2011-01-20 2012-08-09 Jfe Steel Corp Stainless-clad steel excellent in chemical resistance

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1995341A1 (en) * 2007-03-26 2008-11-26 Sumitomo Metal Industries Limited Oil well pipe for expansion in well and two-phase stainless steel for use as oil well pipe for expansion
EP1995341A4 (en) * 2007-03-26 2010-03-10 Sumitomo Metal Ind Oil well pipe for expansion in well and two-phase stainless steel for use as oil well pipe for expansion
JP2012149309A (en) * 2011-01-20 2012-08-09 Jfe Steel Corp Stainless-clad steel excellent in chemical resistance

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