JPS61123497A - Filler metal - Google Patents
Filler metalInfo
- Publication number
- JPS61123497A JPS61123497A JP24223084A JP24223084A JPS61123497A JP S61123497 A JPS61123497 A JP S61123497A JP 24223084 A JP24223084 A JP 24223084A JP 24223084 A JP24223084 A JP 24223084A JP S61123497 A JPS61123497 A JP S61123497A
- Authority
- JP
- Japan
- Prior art keywords
- corrosion
- stainless steel
- ferrite
- less
- steel
- 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
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
- B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
- B23K35/24—Selection of soldering or welding materials proper
- B23K35/30—Selection of soldering or welding materials proper with the principal constituent melting at less than 1550 degrees C
- B23K35/3053—Fe as the principal constituent
- B23K35/308—Fe as the principal constituent with Cr as next major constituent
- B23K35/3086—Fe as the principal constituent with Cr as next major constituent containing Ni or Mn
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Gasket Seals (AREA)
Abstract
Description
【発明の詳細な説明】
(産業上の利用分野)
本発明は、炭素鋼、低合金鋼又はオーステナイト系ステ
ンレス鋼などの鋼種に対応し、防食対象個所の肉盛溶接
する際に使用される溶加材に関する。Detailed Description of the Invention (Field of Industrial Application) The present invention is applicable to steel types such as carbon steel, low-alloy steel, or austenitic stainless steel, and is applicable to welding of corrosion-protected areas. Regarding filling materials.
(従来の技術)
オーステナイト系ステンレス鋼は諸性質が優れてl!P
シ、装置材料として広く供用されてきたが、海水などの
塩素イオンCd、−を含む環境では孔食、隙間腐食など
の局部腐食を生じるという欠点がある。・
約25 % Or を基とするオーステナイト0とフ
ェライト(ロ)の両相が共存する2相ステンレス鋼は耐
食性に優れてオリ、これらの欠点を補うことができるが
、強度が高く加工が困難であったり、組織が不安定であ
ったりして製造コストが高く、高価である。(Prior art) Austenitic stainless steel has excellent properties! P
Although it has been widely used as a material for equipment, it has the disadvantage of causing local corrosion such as pitting corrosion and crevice corrosion in environments containing chlorine ions, such as seawater.・ Duplex stainless steel based on about 25% Or, in which both austenite and ferrite coexist, has excellent corrosion resistance and can compensate for these drawbacks, but it has high strength and is difficult to process. The manufacturing cost is high because the structure is unstable and the manufacturing cost is high.
従って、水密構造物の防食方法として2相ステンレスを
肉盛溶接することが考えられるが、溶接金属は溶加材と
母材とが溶は合って形成されるので2相ステンレスの溶
加材が母材に希釈されて組成が変わってしまう。そのた
め肉感の1層目は所望の2相組織を得にくく、2相組織
を得るためには何層も肉盛りを重ねる必要があシ、構造
物の寸法変形の問題や、工数が多くかかり経済的でない
などの問題がある。Therefore, overlay welding of two-phase stainless steel may be considered as a corrosion prevention method for watertight structures, but since the weld metal is formed by melting the filler metal and the base metal, the filler metal of two-phase stainless steel is It is diluted into the base material and its composition changes. For this reason, it is difficult to obtain the desired two-phase structure in the first layer of fleshy texture, and in order to obtain the two-phase structure, it is necessary to build up many layers, which causes problems of dimensional deformation of the structure and requires a large number of man-hours, making it economical. There are problems such as not being accurate.
(発明が解決しようとする問題点)
本発明は、海水などの塩素イオンCZ−を含む環境にか
けろ水密構造物の孔食や隙間腐食の発生防止のために、
耐海水性の優れる約25%Orを基とするオーステナイ
トQ)、フェライトに)の2相ステンレス鋼を、防食対
象個所だけに適用することができ、かつ安価で、しかも
上記従来法のような欠点のない溶加材を提供しようとす
るものであるう
(問題点を解決するための手段)
本発明は、構造物の防食対象個所を、肉盛溶接によシ耐
海水性の優れる2相ステンレス鋼とするに際し、母材の
溶込みを考えて予め溶加材のCr 含有量を増しておく
ことKよシ、少ない溶接パスで肉盛溶接部を2相組織化
すること、すなわち、肉盛溶接金属は溶加材が母材に薄
められて新たな組成となるので、肉盛溶接後に約25
% (!r を基とするオーステナイ)(r)、フェ
ライト←)の2相組織が得られるように溶加材の組成を
設定するものである。すなわち本発明は炭素鋼、低合金
鋼又はオーステナイト系ステンレス鋼と溶融してなる溶
着金属の組成が、Cr;23〜28チ(重量%、以下同
じ)、N1:3〜8チ、MO;1〜5eI11及びc
: ao as以下、Sl;2−以下、Mn: 2 %
以下ならびにその他の不可避的不純物により構成され、
かつフェライトが40〜60qIIのオーステナイト会
フェライトの2相ステンレス鋼となるようにしたことを
特徴とする溶加材である。(Problems to be Solved by the Invention) The present invention aims to prevent the occurrence of pitting corrosion and crevice corrosion in watertight structures exposed to environments containing chlorine ions CZ- such as seawater.
Duplex stainless steel with austenitic Q) and ferrite based on approximately 25% Or, which has excellent seawater resistance, can be applied only to the areas to be protected against corrosion, is inexpensive, and does not have the drawbacks of the conventional methods mentioned above. (Means for solving the problem) The present invention aims to provide a filler metal that is free from corrosion by overlay welding the corrosion-protected areas of a structure using two-phase stainless steel that has excellent seawater resistance. When making steel, it is better to increase the Cr content of the filler metal in advance in consideration of penetration into the base metal, and to create a two-phase structure in the overlay weld with a few welding passes. The weld metal has a new composition as the filler metal is diluted with the base metal, so after overlay welding, the
The composition of the filler metal is set so as to obtain a two-phase structure of % (!r based on austenite) (r), ferrite←). That is, in the present invention, the composition of the weld metal formed by melting carbon steel, low alloy steel, or austenitic stainless steel is Cr: 23 to 28 inches (weight %, same hereinafter), N1: 3 to 8 inches, MO: 1 ~5eI11 and c
: ao as or less, Sl: 2- or less, Mn: 2%
Consists of the following and other unavoidable impurities:
The filler metal is characterized in that it is a duplex stainless steel of austenitic ferrite with ferrite of 40 to 60qII.
本発明は、海水熱交、海洋構造物、船舶、海水配管など
の海水関連装置や、化学工業反応装彎、公害防止機器な
どで塩素イオンCZ″″を含む環境で供用されろ水密構
造物の製作K、有利に適用することができる。The present invention is applicable to seawater-related equipment such as seawater heat exchangers, marine structures, ships, and seawater piping, chemical industry reaction systems, pollution prevention equipment, etc., which are used in environments containing chlorine ion CZ''. Manufacture K can be advantageously applied.
本発明は、水密構造物の鋼種に対応して、防食対象部の
肉盛溶接部がOr’、 25〜28 vt%。In the present invention, depending on the steel type of the watertight structure, the overlay welded portion of the part to be protected against corrosion is Or', 25 to 28 vt%.
x+; 3〜8 wtチ、Mo: 1〜5 wtチ及び
a : (LO8vt%以下、8凰: 2 vtq11
以下、Mn: 2 wt%以下ならびにその他年可避的
不純物よシなる組成でフェライトに)が40〜60チの
オーステナイトケ)、フェライト@)2相ステンレス鋼
となるような溶加材であって、水密構造物の対象部分が
Or: 5vt%以下、Ml: 5 wt%以下、Mo
: 2 wt%以下、C;α16 vt%以下、Bt:
2 ytl以下、Mn:2wt%以下の炭素鋼または
低合金鋼のときは溶加材はCr: 2 a5〜47wt
%、 Ml: O〜135vtチ、Mo: 0〜a 5
wt%とし、対象部分がCr:15〜20wt%、M
弓7〜12 wt$、Mo;O〜3 vt%、C; Q
、 08 vt%以下、Si;2wt%以下、Mn;
2 wtts以下を主成分とするオーステナイト系ステ
ンレス鋼のときけ、溶加材はmr: 25〜57 wt
%、Ni; 0〜9 wt%XMo: O〜IIL 5
wt%としていずれも母材の溶込み率を10〜40%
とすることにより、母材と溶加材とが溶は合って形成さ
れる溶接金属の3組成及びγ、αの比率を制御して2相
ステンレス鋼とする。x+; 3-8 wt Chi, Mo: 1-5 wt Chi and a: (LO8vt% or less, 8 凰: 2 vtq11
Hereinafter, Mn: 2 wt% or less and other unavoidable impurities are used as a filler metal that becomes ferrite, 40 to 60% austenite, ferrite, and duplex stainless steel. , the target part of the watertight structure is Or: 5vt% or less, Ml: 5wt% or less, Mo
: 2 wt% or less, C; α16 vt% or less, Bt:
For carbon steel or low alloy steel with Mn: 2wt% or less, the filler metal is Cr: 2a5~47wt
%, Ml: O~135vt, Mo: 0~a 5
wt%, and the target part is Cr: 15-20wt%, M
Bow 7-12 wt$, Mo; O-3 vt%, C; Q
, 08 vt% or less, Si; 2wt% or less, Mn;
For austenitic stainless steel whose main component is less than 2 wtts, the filler metal is mr: 25-57 wt.
%, Ni; 0-9 wt%XMo: O-IIL 5
In both cases, the penetration rate of the base metal is 10 to 40% as wt%.
By doing so, the three compositions and the ratios of γ and α of the weld metal formed by melting the base metal and the filler metal are controlled to form a duplex stainless steel.
溶接方法は通常の被覆アーク溶接、T工G溶接、Ml溶
接、プラズマ溶接などで施工できる。溶加材は棒状、ワ
イヤ状などで添加したり、対象面に板状の溶加材を敷い
てその上から溶接アークを当てて溶融させたシすること
が可能である。Welding can be carried out by conventional covered arc welding, T-type G welding, Ml welding, plasma welding, etc. The filler metal can be added in the form of a rod or wire, or it can be melted by laying a plate-shaped filler metal on the target surface and applying a welding arc over it.
得られた表層部は適当な寸法形状に切削加工して供用す
ればよいが、熱処理を施したり、さらに2相ステンレス
鋼を肉盛りすることも可能である。The obtained surface layer portion may be cut into an appropriate size and shape for use, but it is also possible to heat-treat it or to overlay it with duplex stainless steel.
(作用)
溶接金属の組成は母材の組成と溶加材の組成及び双方の
溶接金属への溶込み率によって決まる。表層部を完全に
融合させるためには母材の溶込み率は10%以上とする
必要があシ、また母材の溶込み率が増すと溶加材の・:
r等の含有量を増す必要があり、多すぎると経済的でな
いので溶込み率は4011でに抑見る。溶込み率は母材
温度、溶接入熱などを適当に選ぶことによって通常の方
法で容易に制御できる、母材は一般に海水環境でよく使
用されるr;15〜20 wt%XNl: 7〜12w
tチ、MO;0〜5 wt%程度を含有するJ工S 5
U8304.5UE1316 及びこれらに相当する
鍛鋼、鋳鋼などのオーステナイト系ステンレス鋼を対象
とするが、本発明溶加材は、表層部が2組ステンレス鋼
組織になるものならば、その母材の組成は特に限定され
ない。また、表層部の防食が図れることから炭素鋼、低
合金鋼などのような耐海水性は著しく劣るが安価な材料
を使用することも可能である。(Function) The composition of the weld metal is determined by the composition of the base metal, the composition of the filler metal, and the penetration rate of both into the weld metal. In order to completely fuse the surface layer, the base metal penetration rate must be 10% or more, and as the base metal penetration rate increases, the filler metal...
It is necessary to increase the content of r, etc., and if it is too large, it is not economical, so the penetration rate is suppressed to 4011. The penetration rate can be easily controlled in the usual way by appropriately selecting the base metal temperature, welding heat input, etc. The base metal is generally used in seawater environments r: 15-20 wt%XNl: 7-12w
J-S 5 containing about 0 to 5 wt% of MO;
The target is U8304.5UE1316 and equivalent austenitic stainless steels such as forged steel and cast steel, but if the filler metal of the present invention has a two-set stainless steel structure in the surface layer, the composition of the base metal can be Not particularly limited. Further, since the surface layer can be protected from corrosion, it is also possible to use inexpensive materials such as carbon steel and low alloy steel, which have significantly inferior seawater resistance.
母材がCr: 15〜20 vt%XNl: 7〜12
wt%、Mo; o〜3wt%、 c : a、 o
8 wt%以下、SI: 2 wt%以下、Mn: 2
wt%以下を主成分とするオーステナイト系ステンレ
ス鋼であって母材の溶込み率を10〜40チに制御する
ときは、溶加材はrr: 25〜57 vt%、Ni
e、 O〜9 wt%、Mo: O〜FL 5 wt%
、C: 0.08 wt%以下、sB2 vrt%以下
、Mn; 2 vt%以下とすればよい。オた、母材が
Cr: 3 wt%以下、ll:5vt%以下、Mo;
2 wt%以下、C: [Ll 6 wt%以下、s
!:2wt%以下、Mu: 2 wt%以下を主成分と
する炭素鋼もしくは低合金鋼であって、母材の溶込み率
で10〜401%に制御するときは、溶加材はcr:
25.5〜47 wt%XNl: O〜115 vt%
、ld。Base material is Cr: 15-20 vt%XNl: 7-12
wt%, Mo; o~3wt%, c: a, o
8 wt% or less, SI: 2 wt% or less, Mn: 2
When controlling the penetration rate of the base metal to 10 to 40 in an austenitic stainless steel whose main component is less than wt%, the filler metal is rr: 25 to 57 vt%, Ni
e, O~9 wt%, Mo: O~FL5 wt%
, C: 0.08 wt% or less, sB2 vrt% or less, Mn: 2 vt% or less. Also, the base material is Cr: 3 wt% or less, ll: 5 vt% or less, Mo;
2 wt% or less, C: [Ll 6 wt% or less, s
! : 2 wt% or less, Mu: 2 wt% or less as a main component of carbon steel or low alloy steel, and when controlling the penetration rate of the base metal to 10 to 401%, the filler metal is cr:
25.5-47 wt%XNl: O-115 vt%
,ld.
;0〜a5Wtq6、c ; t3. Q 5 vt9
6以下、81:2vt%以下、Mno 2 vtチ以下
とすればよい。;0~a5Wtq6,c; t3. Q 5 vt9
6 or less, 81:2vt% or less, Mno 2 vtchi or less.
以下、本発明の溶接金属の組成限定理由及びその効果に
ついて述べる。Cr は不動態皮膜を形成して耐食性を
向上させる。耐海水性を向上するには25 Wt−以上
必要である。一方、Orはフェライト@)形成元素であ
るため28%を超えるとフェライトに)が多くなりすぎ
2組組織を維持しにくくなるので、Cr は2゛3〜2
8チの範囲とする。旧 はオーステナイトケ)形成元素
であり、多すぎても少なすぎても2組組織のバランスを
こわすので3〜8 vt%とする。tた、N1 は耐
孔食性を向上させる効果がある。M。The reason for limiting the composition of the weld metal of the present invention and its effects will be described below. Cr forms a passive film and improves corrosion resistance. 25 Wt- or more is required to improve seawater resistance. On the other hand, since Or is a ferrite forming element, if it exceeds 28%, the amount of ferrite becomes too large and it becomes difficult to maintain the two-set structure.
The range is 8 inches. It is an austenite-forming element, and if it is too much or too little, the balance of the two-set structure will be disturbed, so the content is set at 3 to 8 vt%. Additionally, N1 has the effect of improving pitting corrosion resistance. M.
はcr と同様にフェライト@)形成元素であるとと
もに孔食及び隙間腐食を防止するので1〜5wt%とす
る。Cはor化合物を形成してフェライト←)やオース
テナイトケ)中にCr 欠乏領域をつくるのでα08
vt%以下とする。S!及びMnは肉盛溶接部の欠陥発
生を抑止するが、耐食性向上の効果は無いのでそれぞれ
2 Wtfy以下とする。この′ような組成でフェライ
ト@):40〜60チのフェライト@)、オーステナイ
) (752相ステンレス鋼溶接金属は不動態皮膜が安
定で優れた耐海水性を有する。フェライト@):40〜
6゜チの範囲から外れるとフェライト(ロ)が多過ぎて
も少な過ぎても、Or、 cなどの両相中での拡散、均
一化が容易でなく不動態皮膜が破壊されやすくなってし
まい、孔食や隙間腐食などの局部腐食が発生しやすい傾
向になる。Like cr, it is a ferrite forming element and prevents pitting corrosion and crevice corrosion, so it is set at 1 to 5 wt%. C forms an or compound and creates a Cr-deficient region in ferrite←) and austenite←), so α08
vt% or less. S! Although Mn and Mn suppress the occurrence of defects in overlay welds, they do not have the effect of improving corrosion resistance, so they are each set at 2 Wtfy or less. With this composition, ferrite@): 40~60 ferrite@), austenite) (752 phase stainless steel weld metal has a stable passive film and excellent seawater resistance. Ferrite@): 40~
If it is outside the 6° range, whether there is too much or too little ferrite (b), it will not be easy to diffuse and make it uniform in both phases such as Or and C, and the passive film will be easily destroyed. , localized corrosion such as pitting corrosion and crevice corrosion tends to occur.
表1は活性化した35℃の人工海水中(3チNa’J!
+1/20 M Na!s04+活性炭)に試験片を
14日間浸漬1−て隙間腐食試験を行った結果を示す。Table 1 shows activated artificial seawater at 35°C (3-chi Na'J!
+1/20 M Na! The results of a crevice corrosion test performed by immersing a test piece in s04+activated carbon for 14 days are shown below.
すなわち、低合金鋼の表層部を本発明溶加材によって肉
盛溶接して、2組組織と1−た後、第1図に示すような
大小2枚の試験板A、Bを切出し、図示のようKA、B
をテフロン製ボルドーナツトで締めつけて実際に隙間を
形成し、上記活性化した人工海水中に浸漬して腐食発生
状況を調べた。That is, after overlaying the surface layer of low alloy steel with the filler metal of the present invention and forming two sets of structures, two large and small test plates A and B as shown in Fig. 1 were cut out. Like KA, B
was tightened with a Teflon bolt donut to actually form a gap, and then immersed in the activated artificial seawater to examine the occurrence of corrosion.
肉盛溶接金属部は2組とも腐食の発生はなく、同様に行
った2相ステンレス鋼板材(母材)及びオーステナイト
系ステンレス鋼板材(母材)と比較すると肉盛溶接部は
オルステナイト系ステンレス鋼板材より耐隙間腐食性に
優れ、2相ステンレス鋼板材と同等であった。There was no corrosion in the overlay welded metal parts of the two sets, and compared with the duplex stainless steel sheet material (base material) and the austenitic stainless steel sheet material (base material) that were similarly performed, the overlay welded parts were made of orstenitic stainless steel. It had better crevice corrosion resistance than steel plate material and was equivalent to duplex stainless steel plate material.
表1 0:腐食なし、×:腐食Table 1 0: No corrosion, ×: Corrosion
第1図は、本発明溶加材の効果を確認するために作製し
た試験片の概要を説明するだめの図である。
復代理人 内 1) 明
復代理人 萩 原 亮 −FIG. 1 is a diagram illustrating the outline of a test piece prepared to confirm the effect of the filler metal of the present invention. Sub-agents 1) Meifuku agent Ryo Hagiwara -
Claims (1)
溶融してなる溶着金属の組成が、Cr;23〜28%(
重量%、以下同じ)、Ni;3〜8%、Mo;1〜5%
、及びC;0.08%以下、Si;2%以下、Mn;2
%以下ならびにその他の不可避的不純物により構成され
、かつフェライトが40〜60%のオーステナイト・フ
ェライトの2相ステンレス鋼となるようにしたことを特
徴とする溶加材。The composition of the weld metal obtained by melting carbon steel, low alloy steel, or austenitic stainless steel is Cr; 23 to 28% (
weight%, the same applies hereinafter), Ni: 3 to 8%, Mo: 1 to 5%
, and C; 0.08% or less, Si; 2% or less, Mn; 2
% or less and other unavoidable impurities, and is characterized by being an austenite-ferrite duplex stainless steel containing 40 to 60% ferrite.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP24223084A JPS61123497A (en) | 1984-11-19 | 1984-11-19 | Filler metal |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP24223084A JPS61123497A (en) | 1984-11-19 | 1984-11-19 | Filler metal |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS61123497A true JPS61123497A (en) | 1986-06-11 |
Family
ID=17086166
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP24223084A Pending JPS61123497A (en) | 1984-11-19 | 1984-11-19 | Filler metal |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS61123497A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0415570A2 (en) * | 1989-08-01 | 1991-03-06 | Ishikawajima-Harima Heavy Industries Co., Ltd. | Corrosion resistant stainless steel |
-
1984
- 1984-11-19 JP JP24223084A patent/JPS61123497A/en active Pending
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0415570A2 (en) * | 1989-08-01 | 1991-03-06 | Ishikawajima-Harima Heavy Industries Co., Ltd. | Corrosion resistant stainless steel |
EP0415570B1 (en) * | 1989-08-01 | 1996-03-13 | Ishikawajima-Harima Heavy Industries Co., Ltd. | Corrosion resistant stainless steel |
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