JP2000045058A - Dew point corrosion preventing method - Google Patents
Dew point corrosion preventing methodInfo
- Publication number
- JP2000045058A JP2000045058A JP21120598A JP21120598A JP2000045058A JP 2000045058 A JP2000045058 A JP 2000045058A JP 21120598 A JP21120598 A JP 21120598A JP 21120598 A JP21120598 A JP 21120598A JP 2000045058 A JP2000045058 A JP 2000045058A
- Authority
- JP
- Japan
- Prior art keywords
- corrosion
- spraying method
- dew point
- test piece
- point 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
Links
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】この発明は、たとえばごみ焼
却設備の煙道および煙突内筒等や、ごみ焼却設備に組み
込まれているごみを燃料とするボイラのエコノマイザ等
の露点腐食環境下に置かれる器材の露点腐食、特に塩酸
露点腐食を防止する方法に関する。The present invention relates to a dew-point corrosive environment such as a flue and a chimney inner tube of a refuse incineration plant, and an economizer of a boiler using refuse as a fuel incorporated in the refuse incineration plant. The present invention relates to a method for preventing dew point corrosion of equipment, particularly hydrochloric acid dew point corrosion.
【０００２】[0002]
【従来の技術と発明が解決しようとする課題】従来、ご
み焼却設備の器材は、たとえばJIS ＳＳ４１等の一般構
造用圧延鋼材でつくられていた。従来のごみ焼却整備で
は、排ガスの温度はかなり高温であり、煙道および煙突
内筒等や、ごみ焼却設備に組み込まれているごみを燃料
とするボイラのエコノマイザ等が露点腐食環境下に置か
れることはなく、露点腐食の問題はなかった。2. Description of the Related Art Conventionally, equipment for refuse incineration equipment has been made of rolled steel for general structures such as JIS SS41. In conventional refuse incineration, the temperature of exhaust gas is quite high, and the flue and the stack of chimneys, and the economizer of a boiler using refuse as fuel built in refuse incineration equipment are placed in a dew-point corrosive environment. There was no problem of dew point corrosion.
【０００３】ところが、最近では、ダイオキシンの発生
防止等排ガス規制の要求が厳しくなっており、これに対
応するためには、必然的に排ガスの温度を低くしなけれ
ばならない。すると、ごみ焼却設備の上述したような器
材が露点腐食環境下に置かれることになり、露点腐食、
特に塩酸露点腐食が発生するという問題がある。In recent years, however, the requirements for exhaust gas regulations, such as the prevention of dioxin generation, have become strict, and in order to respond to this, the temperature of exhaust gas must necessarily be lowered. Then, the above-mentioned equipment of the refuse incinerator will be placed in a dew-point corrosion environment,
In particular, there is a problem that hydrochloric acid dew point corrosion occurs.
【０００４】ところで、通常のボイラでは、燃焼排ガス
中のＳＯ3 に起因する硫酸露点腐食を防止するために、
硫酸露点腐食環境下に置かれる器材は、Ｃｒ１．２ｗｔ
％、Ｓｉ０．５ｗｔ％、Ｃｕ０．３ｗｔ％およびＳ０．
０２ｗｔ％を含み、残部Ｆｅおよび不可避不純物からな
る耐硫酸露点腐食鋼で形成されており、ごみ焼却設備の
露点腐食環境下に置かれる器材をこの耐硫酸露点腐食鋼
で形成することも考えられる。しかしながら、この耐硫
酸露点腐食鋼は、塩酸露点腐食の発生を防止することは
できず、主に塩酸露点腐食が発生するごみ焼却設備にお
ける塩酸露点腐食環境下に置かれる器材を上記の耐硫酸
露点腐食鋼で形成したとしても、露点腐食防止効果は得
られないことが判明した。Incidentally, in a normal boiler, in order to prevent sulfuric acid dew point corrosion caused by SO 3 in combustion exhaust gas,
Equipment placed under sulfuric acid dew point corrosion environment is Cr1.2wt
%, 0.5 wt% of Si, 0.3 wt% of Cu and
It is made of sulfuric acid dew-point corrosion resistant steel containing 02 wt%, the balance being Fe and unavoidable impurities. It is also conceivable that equipment placed under the dew-point corrosion environment of refuse incineration equipment is made of this sulfuric acid dew-point corrosion resistant steel. However, this sulfuric acid dew-point corrosion resistant steel cannot prevent the occurrence of hydrochloric acid dew-point corrosion. It was found that even when formed of corroded steel, the effect of preventing dew point corrosion was not obtained.
【０００５】そこで、このような問題を解決するため
に、ごみ焼却設備における露点腐食環境下に置かれる器
材全体をJIS ＳＵＳ３０４、ＳＵＳ３１６Ｌ等のオース
テナイト系ステンレス鋼で形成することも考えられる
が、この場合材料コストが高くなるという問題がある。[0005] In order to solve such a problem, it is conceivable that the entire equipment placed in a dew-point corrosive environment in a refuse incinerator is made of austenitic stainless steel such as JIS SUS304 or SUS316L. There is a problem that the material cost increases.
【０００６】この発明の目的は、上記問題を解決し、露
点腐食、特に塩酸露点腐食の発生を防止することのでき
るコストの安い露点腐食防止方法を提供することにあ
る。An object of the present invention is to solve the above-mentioned problems and to provide a low-cost dew-point corrosion prevention method capable of preventing the occurrence of dew-point corrosion, particularly hydrochloric acid dew-point corrosion.
【０００７】[0007]
【課題を解決するための手段と発明の効果】この発明に
よる露点腐食防止方法は、露点腐食環境下に置かれる器
材の表面に、爆発溶射法または高速ガス炎溶射法によ
り、Ｎｉ８０〜２０ｗｔ％およびＣｒ１５〜５０ｗｔ％
（但し、ＮｉとＣｒの合計量は６０ｗｔ％以上である）
を含み、残部不可避不純物からなる合金の溶射皮膜を形
成することを特徴とするものである。The method for preventing dew-point corrosion according to the present invention is a method for preventing the dew-point corrosion of 80 to 20 wt% of Ni by explosive spraying or high-speed gas flame spraying on the surface of equipment placed in a dew-point corrosion environment. Cr15-50wt%
(However, the total amount of Ni and Cr is 60 wt% or more.)
And forming a thermal spray coating of an alloy comprising the remaining unavoidable impurities.
【０００８】上記において、溶射皮膜を形成する合金中
のＮｉ含有量を８０〜２０ｗｔ％に限定したのは、８０
ｗｔ％を越えるとＣｒの含有量が相対的に減少し、Ｃｒ
の不動態化膜が十分形成されないからであり、２０ｗｔ
％未満であると耐食性を有する単相（γ相）が形成しに
くいからである。In the above, the reason why the Ni content in the alloy forming the thermal spray coating is limited to 80 to 20 wt% is as follows.
If the content exceeds wt%, the Cr content relatively decreases,
This is because the passivation film of
%, It is difficult to form a corrosion-resistant single phase (γ phase).
【０００９】また、溶射皮膜を形成する合金中のＣｒ含
有量を１５〜５０ｗｔ％に限定したのは、１５ｗｔ％未
満であるとＣｒの不動態化膜が十分形成されないからで
あり、５０ｗｔ％を越えると耐食性を有する単相（γ
相）が形成しにくいからである。The reason why the Cr content in the alloy forming the thermal spray coating is limited to 15 to 50 wt% is that if less than 15 wt%, a passivation film of Cr is not sufficiently formed. Beyond that, the corrosion-resistant single phase (γ
Phase) is difficult to form.
【００１０】ＮｉとＣｒの合計量を６０ｗｔ％以上とし
たのは、６０ｗｔ％未満では露点腐食防止効果が得られ
ないからである。ＮｉとＣｒの合計量は７０ｗｔ％が好
ましく、より多いほうが望ましい。たとえば、最も望ま
しいのは１００ｗｔ％である。The reason why the total amount of Ni and Cr is set to 60 wt% or more is that if less than 60 wt%, the effect of preventing dew point corrosion cannot be obtained. The total amount of Ni and Cr is preferably 70% by weight, and more preferably. For example, 100 wt% is most desirable.
【００１１】この発明の露点腐食防止方法によれば、露
点腐食環境下に置かれる器材の露点腐食、特に塩酸露点
腐食を防止することができる。According to the dew-point corrosion prevention method of the present invention, dew-point corrosion of equipment placed in a dew-point corrosion environment, particularly hydrochloric acid dew-point corrosion, can be prevented.
【００１２】この発明の露点腐食防止方法において、溶
射皮膜を形成する合金が、さらにＷ５〜１５ｗｔ％およ
びＭｏ５〜１５ｗｔ％のうちの１種または２種を含む
（但し、ＷとＭｏの両者を含む場合の合計量は２０ｗｔ
％以下である）ことがある。この場合、溶射皮膜が非晶
質化し、その耐食性が一層向上する。ＷおよびＭｏ含有
量を上記のように限定したのは、Ｗ含有量が５ｗｔ％未
満であり、Ｍｏ含有量が５ｗｔ％未満であると耐食性向
上効果が得られず、Ｗ含有量が１５ｗｔ％を越え、Ｍｏ
含有量が１５ｗｔ％を越えると非晶質化した皮膜が脆く
なるからである。また、ＷおよびＭｏの両者を含む場合
の合計量の上限値を２０ｗｔ％としたのは、２０ｗｔ％
を越えると同じく非晶質化した皮膜が脆くなるからであ
る。In the method for preventing dew-point corrosion according to the present invention, the alloy forming the thermal sprayed coating further contains one or two of W5 to 15 wt% and Mo5 to 15 wt% (however, both W and Mo are included). The total amount in the case is 20wt
% Or less). In this case, the thermal spray coating becomes amorphous and its corrosion resistance is further improved. The reason why the W and Mo contents are limited as described above is that the W content is less than 5 wt%, and if the Mo content is less than 5 wt%, the effect of improving corrosion resistance cannot be obtained, and the W content is 15 wt%. Over, Mo
If the content exceeds 15 wt%, the amorphous film becomes brittle. Further, the upper limit of the total amount when both W and Mo are included is set to 20 wt%,
This is because when the ratio exceeds the above, the film which has been made amorphous similarly becomes brittle.
【００１３】この発明の露点腐食防止方法において、溶
射皮膜を形成する合金が、さらにＢ２〜５ｗｔ％、Ｓｉ
２〜５ｗｔ％およびＦｅ２〜５ｗｔ％のうちの１種また
は２種以上含む（但し、Ｂ、ＳｉおよびＦｅのうちの２
種以上を含む場合の合計量は６〜８ｗｔ％である）こと
ある。この場合、上記合金の融点が下がり、形成された
溶射皮膜に熱処理を施すことにより溶射皮膜の緻密性を
向上させることができ、その結果溶射皮膜の耐食性が一
層向上する。Ｂ、ＳｉおよびＦｅ含有量を上記のように
限定したのは、Ｂ含有量が２ｗｔ％未満であり、Ｓｉ含
有量が２ｗｔ％未満であり、Ｆｅ含有量が２ｗｔ％未満
であると融点を下げる効果が得られず、Ｂ含有量が５ｗ
ｔ％を越え、Ｓｉ含有量が５ｗｔ％を越え、Ｆｅ含有量
が５ｗｔ％を越えると耐食性が低下するからである。ま
た、Ｂ、ＳｉおよびＦｅを２種以上含む場合の合計量の
下限値を６ｗｔ％に限定し、上限値を８ｗｔ％に限定し
たのは、６ｗｔ％未満であると融点を下げる効果が得ら
れず、８ｗｔ％を越えると耐食性が低下するからであ
る。[0013] In the method for preventing dew-point corrosion of the present invention, the alloy forming the thermal spray coating further contains B2 to 5 wt%,
2 to 5 wt% and one or more of Fe 2 to 5 wt% (however, 2 out of B, Si and Fe are contained).
The total amount when including more than one species is 6-8 wt%). In this case, the melting point of the alloy is lowered, and the thermal spray coating formed is subjected to heat treatment, whereby the denseness of the spray coating can be improved, and as a result, the corrosion resistance of the spray coating further improves. The B, Si and Fe contents are limited as described above because the B content is less than 2 wt%, the Si content is less than 2 wt%, and the Fe content is less than 2 wt%, the melting point is lowered. No effect, B content 5w
This is because when the content exceeds t%, the Si content exceeds 5 wt%, and the Fe content exceeds 5 wt%, the corrosion resistance decreases. The reason why the lower limit of the total amount is limited to 6 wt% and the upper limit is limited to 8 wt% when two or more kinds of B, Si and Fe are contained is that the melting point is reduced when the content is less than 6 wt%. If the content exceeds 8% by weight, the corrosion resistance decreases.
【００１４】この発明の露点腐食防止方法において、溶
射法として爆発溶射法または高速ガス炎溶射法（以下、
ＨＶＯＦという）を採用したのは、他の溶射法に比べて
緻密な溶射皮膜を形成することが可能となり、これによ
り形成された溶射皮膜の耐食性が優れているからであ
る。特に、ＨＶＯＦは現場施工が可能であるので、既設
の器材、たとえば既設のごみ焼却設備の煙道内面や煙突
内筒内面やエコノマイザ等にも溶射皮膜を形成すること
ができる。In the method for preventing dew-point corrosion of the present invention, an explosive spraying method or a high-speed gas flame spraying method (hereinafter, referred to as a spraying method) is used as a spraying method.
The reason why HVOF is used is that it is possible to form a dense sprayed coating as compared with other spraying methods, and the formed sprayed coating has excellent corrosion resistance. In particular, since HVOF can be constructed on site, a thermal spray coating can be formed on existing equipment, for example, the inner surface of a flue, the inner surface of a chimney cylinder, or an economizer of an existing refuse incinerator.
【００１５】この発明の露点腐食防止方法において、形
成する溶射皮膜の膜厚は２００〜５００μｍであること
が好ましい。溶射皮膜の膜厚が２００μｍ未満であると
充分な耐食性が得られず、５００μｍを越えても耐食性
は変化しないが、施工条件が悪くなり、かつコストが高
くなるからである。In the method for preventing dew-point corrosion of the present invention, the thickness of the thermal spray coating to be formed is preferably 200 to 500 μm. If the thickness of the thermal sprayed coating is less than 200 μm, sufficient corrosion resistance cannot be obtained, and if it exceeds 500 μm, the corrosion resistance does not change, but the working conditions deteriorate and the cost increases.
【００１６】[0016]
【発明の実施の形態】以下、この発明を、具体的実施例
および比較例を基にして説明する。DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on specific examples and comparative examples.
【００１７】実施例１ JIS ＳＳ４１からなる長さ１００ｍｍ、幅８０ｍｍ、厚
さ５ｍｍの基板の全表面、すなわち両面および全周面
に、Ｎｉ５０ｗｔ％およびＣｒ５０ｗｔ％からなる合金
粉末（不可避不純物は含む）を用いて、ＨＶＯＦにより
目標膜厚３００μｍとして溶射皮膜を形成し、試験片を
つくった。そして、この試験片を６０℃の０．１ｗｔ％
ＨＣｌ水溶液中に３２日間浸漬した。Example 1 An alloy powder composed of 50 wt% of Ni and 50 wt% of Cr (including unavoidable impurities) is provided on the entire surface of a substrate made of JIS SS41 having a length of 100 mm, a width of 80 mm and a thickness of 5 mm, that is, both surfaces and the entire peripheral surface. Using HVOF, a thermal spray coating was formed with a target film thickness of 300 μm to prepare a test piece. Then, this test piece is 0.1 wt% at 60 ° C.
It was immersed in an aqueous HCl solution for 32 days.
【００１８】実施例２ Ｎｉ７５ｗｔ％、Ｃｒ１７ｗｔ％、Ｂ２ｗｔ％、Ｓｉ３
ｗｔ％およびＦｅ３ｗｔ％を含み、残部不可避不純物か
らなる合金粉末を用いて溶射皮膜を形成したことを除い
ては、上記実施例１と同様にして試験片をつくった。そ
して、この試験片を６０℃の０．１ｗｔ％ＨＣｌ水溶液
中に３２日間浸漬した。Example 2 Ni 75 wt%, Cr 17 wt%, B 2 wt%, Si 3
A test piece was prepared in the same manner as in Example 1 except that a thermal spray coating was formed using an alloy powder containing wt% and Fe3 wt% and the balance consisting of unavoidable impurities. Then, this test piece was immersed in a 0.1 wt% HCl aqueous solution at 60 ° C. for 32 days.
【００１９】比較例１ JIS ＳＳ４１からなる長さ１００ｍｍ、幅８０ｍｍ、厚
さ３ｍｍの板状試験片をつくった。そして、この試験片
を６０℃の０．１ｗｔ％ＨＣｌ水溶液中に３２日間浸漬
した。浸漬後、その表面には赤錆が発生していた。Comparative Example 1 A plate-like test piece of JIS SS41 having a length of 100 mm, a width of 80 mm and a thickness of 3 mm was prepared. Then, this test piece was immersed in a 0.1 wt% HCl aqueous solution at 60 ° C. for 32 days. After immersion, red rust was generated on the surface.
【００２０】比較例２ Ｃｒ１．２ｗｔ％、Ｓｉ０．５ｗｔ％、Ｃｕ０．３ｗｔ
％およびＳ０．０２ｗｔ％を含み、残部不可避不純物お
よびＦｅからなる長さ１００ｍｍ、幅８０ｍｍ、厚さ３
ｍｍの板状試験片をつくった。そして、この試験片を６
０℃の０．１ｗｔ％ＨＣｌ水溶液中に３２日間浸漬し
た。浸漬後、その表面には赤錆が発生していた。比較例
３ JIS ＳＵＳ４１０からなる長さ１００ｍｍ、幅８０ｍ
ｍ、厚さ３ｍｍの板状試験片をつくった。そして、この
試験片を６０℃の０．１ｗｔ％ＨＣｌ水溶液中に３２日
間浸漬した。Comparative Example 2 Cr 1.2 wt%, Si 0.5 wt%, Cu 0.3 wt
% Of S, 0.02 wt%, and 100% in length, 80 mm in width, and 3 in thickness, which are made up of the remaining unavoidable impurities and Fe.
mm plate specimens were prepared. And this test piece is
It was immersed in a 0.1 wt% HCl aqueous solution at 0 ° C. for 32 days. After immersion, red rust was generated on the surface. Comparative Example 3 Length 100 mm, width 80 m made of JIS SUS410
m, a plate-shaped test piece having a thickness of 3 mm was prepared. Then, this test piece was immersed in a 0.1 wt% HCl aqueous solution at 60 ° C. for 32 days.
【００２１】比較例４ JIS ＳＵＳ３０４からなる長さ１００ｍｍ、幅８０ｍ
ｍ、厚さ３ｍｍの板状試験片をつくった。そして、この
試験片を６０℃の０．１ｗｔ％ＨＣｌ水溶液中に３２日
間浸漬した。Comparative Example 4 JIS SUS304 100 mm long and 80 m wide
m, a plate-shaped test piece having a thickness of 3 mm was prepared. Then, this test piece was immersed in a 0.1 wt% HCl aqueous solution at 60 ° C. for 32 days.
【００２２】比較例５ JIS ＳＵＳ３１６Ｌからなる長さ１００ｍｍ、幅８０ｍ
ｍ、厚さ３ｍｍの板状試験片をつくった。そして、この
試験片を６０℃の０．１ｗｔ％ＨＣｌ水溶液中に３２日
間浸漬した。Comparative Example 5 JIS SUS316L 100 mm long and 80 m wide
m, a plate-shaped test piece having a thickness of 3 mm was prepared. Then, this test piece was immersed in a 0.1 wt% HCl aqueous solution at 60 ° C. for 32 days.
【００２３】比較例６ Ａｌ５ｗｔ％を含み、残部不可避不純物およびＺｎから
なる合金粉末を用いて溶射皮膜を形成したことを除いて
は、上記実施例１と同様にして試験片をつくった。そし
て、この試験片を６０℃の０．１ｗｔ％ＨＣｌ水溶液中
に３２日間浸漬した。Comparative Example 6 A test piece was prepared in the same manner as in Example 1 except that a thermal spray coating was formed using an alloy powder containing 5 wt% of Al and the balance of unavoidable impurities and Zn. Then, this test piece was immersed in a 0.1 wt% HCl aqueous solution at 60 ° C. for 32 days.
【００２４】比較例７ 工業用純Ａｌからなる粉末を用いて溶射皮膜を形成した
ことを除いては、上記実施例１と同様にして試験片をつ
くった。そして、この試験片を６０℃の０．１ｗｔ％Ｈ
Ｃｌ水溶液中に３２日間浸漬した。Comparative Example 7 A test piece was prepared in the same manner as in Example 1 except that a thermal spray coating was formed using a powder of industrial pure Al. Then, this test piece was placed in 0.1 wt% H at 60 ° C.
It was immersed in a Cl aqueous solution for 32 days.
【００２５】そして、上記実施例１〜２および比較例１
〜７の浸漬後の各試験片の腐食速度を測定した。その結
果を図１に示す。図１から、実施例１および２では、比
較例４および５と同様にほとんど腐食は認められず、比
較例１〜３、６および７ではかなり腐食していることが
分かる。The above Examples 1 and 2 and Comparative Example 1
The corrosion rate of each of the test pieces after immersion was measured. The result is shown in FIG. From FIG. 1, it can be seen that almost no corrosion was observed in Examples 1 and 2, as in Comparative Examples 4 and 5, and considerable corrosion was observed in Comparative Examples 1-3, 6, and 7.
【００２６】実施例３ 上記実施例１で用いたのと同じ試験片を、６０℃の０．
１ｗｔ％ＨＣｌ水溶液中に１６時間浸漬した後１５０℃
の加熱炉内に８時間保持する、という試験を３２日間行
った。６０℃の０．１ｗｔ％ＨＣｌ水溶液中に１６時間
浸漬→１５０℃の加熱炉内に８時間保持という条件は、
実際のごみ焼却設備の操業条件に模した条件である。試
験後の試験片の表面を観察したところ、Ｃｒ酸化物と思
われる緑色に着色したものが認められたが、表面状態は
初期状態とほぼ変わりなかった。Example 3 The same test piece as used in Example 1 was used at 60.degree.
After immersion in a 1 wt% HCl aqueous solution for 16 hours, 150 ° C
For 8 hours was carried out for 32 days. The condition of immersing in a 0.1 wt% HCl aqueous solution at 60 ° C. for 16 hours → holding in a heating furnace at 150 ° C. for 8 hours is as follows.
These conditions mimic the operating conditions of actual waste incineration equipment. Observation of the surface of the test piece after the test showed that the test piece was colored green which was considered to be Cr oxide, but the surface state was almost the same as the initial state.
【００２７】実施例４ 上記実施例２で用いたのと同じ試験片を、６０℃の０．
１ｗｔ％ＨＣｌ水溶液中に１６時間浸漬した後１５０℃
の加熱炉内に８時間保持する、という試験を３２日間行
った。試験後の試験片の表面を観察したところ、Ｃｒ酸
化物と思われる緑色に着色したものが認められたが、表
面状態は初期状態とほぼ変わりなかった。Example 4 The same test piece as used in Example 2 was used at 60.degree.
After immersion in a 1 wt% HCl aqueous solution for 16 hours, 150 ° C
For 8 hours was carried out for 32 days. Observation of the surface of the test piece after the test showed that the test piece was colored green which was considered to be Cr oxide, but the surface state was almost the same as the initial state.
【００２８】比較例８ 上記比較例１で用いたのと同じ試験片を、６０℃の０．
１ｗｔ％ＨＣｌ水溶液中に１６時間浸漬した後１５０℃
の加熱炉内に８時間保持する、という試験を３２日間行
った。COMPARATIVE EXAMPLE 8 The same test piece as used in Comparative Example 1 was used at 0.degree.
After immersion in a 1 wt% HCl aqueous solution for 16 hours, 150 ° C
For 8 hours was carried out for 32 days.
【００２９】比較例９ 上記比較例４で用いたのと同じ試験片を、６０℃の０．
１ｗｔ％ＨＣｌ水溶液中に１６時間浸漬した後１５０℃
の加熱炉内に８時間保持する、という試験を３２日間行
った。COMPARATIVE EXAMPLE 9 The same test piece as used in Comparative Example 4 was used at 0.degree.
After immersion in a 1 wt% HCl aqueous solution for 16 hours, 150 ° C
For 8 hours was carried out for 32 days.
【００３０】比較例１０ 上記比較例５で用いたのと同じ試験片を、６０℃の０．
１ｗｔ％ＨＣｌ水溶液中に１６時間浸漬した後１５０℃
の加熱炉内に８時間保持する、という試験を３２日間行
った。Comparative Example 10 The same test piece as used in Comparative Example 5 was used at 60 ° C.
After immersion in a 1 wt% HCl aqueous solution for 16 hours, 150 ° C
For 8 hours was carried out for 32 days.
【００３１】比較例１１ 上記比較例６で用いたのと同じ試験片を、６０℃の０．
１ｗｔ％ＨＣｌ水溶液中に１６時間浸漬した後１５０℃
の加熱炉内に８時間保持する、という試験を３２日間行
った。Comparative Example 11 The same test piece as used in Comparative Example 6 was used at 60 ° C.
After immersion in a 1 wt% HCl aqueous solution for 16 hours, 150 ° C
For 8 hours was carried out for 32 days.
【００３２】比較例１２ 上記比較例７で用いたのと同じ試験片を、６０℃の０．
１ｗｔ％ＨＣｌ水溶液中に１６時間浸漬した後１５０℃
の加熱炉内に８時間保持する、という試験を３２日間行
った。Comparative Example 12 The same test piece as used in Comparative Example 7 was used at 60 ° C.
After immersion in a 1 wt% HCl aqueous solution for 16 hours, 150 ° C
For 8 hours was carried out for 32 days.
【００３３】そして、上記実施例３〜４および比較例８
〜１２の浸漬後の各試験片の腐食速度を測定した。その
結果を図２に示す。図２から、実施例３および４では、
比較例９および１０と同様にほとんど腐食は認められ
ず、比較例８、１１および１２ではかなり腐食している
ことが分かる。Then, the above Examples 3 to 4 and Comparative Example 8
The corrosion rate of each test piece after immersion was measured. The result is shown in FIG. From FIG. 2, in Examples 3 and 4,
As in Comparative Examples 9 and 10, almost no corrosion was observed, and it can be seen that Comparative Examples 8, 11, and 12 were considerably corroded.
【００３４】実施例５ 上記実施例１で用いたのと同じ試験片を、実際のごみ焼
却設備の煙道内に７７０４時間放置した。Example 5 The same test piece as used in Example 1 was allowed to stand for 7704 hours in the flue of an actual refuse incinerator.
【００３５】実施例６ 上記実施例２で用いたのと同じ試験片を、実際のごみ焼
却設備の煙道内に７７０４時間放置した。Example 6 The same test piece as used in Example 2 was left in the flue of an actual refuse incinerator for 7704 hours.
【００３６】実施例７ 上記実施例６で用いたのと同じ試験片の溶射皮膜表面
に、封孔剤を塗布したものを、実際のごみ焼却設備の煙
道内に７７０４時間放置した。Example 7 The same test piece as that used in Example 6 except that the surface of the sprayed coating was coated with a sealing agent was allowed to stand in a flue of an actual refuse incinerator for 7704 hours.
【００３７】実施例８ JIS ＳＳ４１からなる長さ１００ｍｍ、幅８０ｍｍ、厚
さ５ｍｍの基板の全表面、すなわち両面および全周面
に、Ｃｒ２０ｗｔ％およびＷ１０ｗｔ％を含み、残部不
可避不純物およびＮｉからなる合金粉末を用いて、ＨＶ
ＯＦにより目標膜厚３００μｍとして溶射皮膜を形成し
て試験片をつくった。そして、この試験片を、実際のご
み焼却設備の煙道内に７７０４時間放置した。EXAMPLE 8 An alloy comprising 20 wt% of Cr and 10 wt% of W on the entire surface of a substrate made of JIS SS41 having a length of 100 mm, a width of 80 mm and a thickness of 5 mm, that is, both surfaces and the entire peripheral surface, the balance being inevitable impurities and Ni HV using powder
A test piece was prepared by forming a sprayed coating with a target film thickness of 300 μm by OF. And this test piece was left for 7704 hours in the flue of the actual refuse incineration plant.
【００３８】実施例９ JIS ＳＳ４１からなる長さ１００ｍｍ、幅８０ｍｍ、厚
さ５ｍｍの基板の全表面、すなわち両面および全周面
に、Ｃｒ１８ｗｔ％、Ｍｏ６ｗｔ％および不純物として
のＦｅ５ｗｔ％を含み、残部不可避不純物およびＮｉか
らなる合金粉末を用いて、ＨＶＯＦにより目標膜厚３０
０μｍとして溶射皮膜を形成して試験片をつくった。そ
して、この試験片を、実際のごみ焼却設備の煙道内に７
７０４時間放置した。Example 9 The entire surface of a substrate made of JIS SS41 and having a length of 100 mm, a width of 80 mm, and a thickness of 5 mm, that is, 18 wt% of Cr, 6 wt% of Mo, and 5 wt% of Fe as an impurity were inevitably contained on the entire surface and both peripheral surfaces, and the remainder was inevitable. Using an alloy powder consisting of impurities and Ni, target film thickness 30
A test piece was prepared by forming a thermal spray coating at 0 μm. Then, place this test piece in the flue of actual waste incineration equipment.
It was left for 704 hours.
【００３９】比較例１３ 上記比較例１で用いたのと同じ試験片を、実際のごみ焼
却設備の煙道内に７７０４時間放置した。Comparative Example 13 The same test piece as used in Comparative Example 1 was left for 7704 hours in the flue of an actual refuse incinerator.
【００４０】比較例１４ 上記比較例４で用いたのと同じ試験片を、実際のごみ焼
却設備の煙道内に７７０４時間放置した。Comparative Example 14 The same test piece used in Comparative Example 4 was allowed to stand for 7704 hours in the flue of an actual refuse incinerator.
【００４１】比較例１５ 上記比較例５で用いたのと同じ試験片を、実際のごみ焼
却設備の煙道内に７７０４時間放置した。Comparative Example 15 The same test piece as used in Comparative Example 5 was left for 7704 hours in the flue of an actual refuse incinerator.
【００４２】なお、上記実施例５〜９および比較例１３
〜１５において、試験開始時および終了時の煙道内の曝
露環境は表１に示す通りである。なお、表１は、１ｇ／
２０ｍｌＨ2 Ｏで抽出した成分を分析したものである。The above Examples 5 to 9 and Comparative Example 13
At ~ 15, the exposure environment in the flue at the start and end of the test is as shown in Table 1. Table 1 shows that 1 g /
This is an analysis of components extracted with 20 ml H 2 O.
【００４３】[0043]
【表１】 上記実施例５〜９および比較例１３〜１５の試験後の外
観を観察したところ、比較例１３の試験片の表層全体
に、煙道内面と同様に赤褐色の錆が発生していた。この
錆層は剥離性の大きいものではないが、ごみ焼却設備の
操業時に微量ながら飛散すると想定される。比較例１４
および１５の試験片の表面には赤錆の発生は認められな
かったが、孔食が発生していた。実施例５〜９の各試験
片の溶射皮膜の表面にはＣｒ酸化物と思われる緑色に着
色したものが認められたが、表面状態は初期状態とほぼ
変わりなかった。また、実施例５〜９の各試験片の溶射
皮膜の断面ミクロ観察を行ったところ、緑色に着色した
部分において、微小な孔食が観察されたが、溶射皮膜内
部には腐食が進行することによる腐食生成物が形成した
ような介在物は認められなかった。[Table 1] Observation of the appearance of the test pieces of Examples 5 to 9 and Comparative Examples 13 to 15 showed that reddish brown rust occurred on the entire surface layer of the test piece of Comparative Example 13 as in the inner surface of the flue. Although this rust layer does not have a large releasability, it is assumed that a small amount of the rust layer is scattered during operation of the refuse incinerator. Comparative Example 14
No red rust was observed on the surfaces of the test pieces No. 15 and No. 15, but pitting occurred. Although the surface of the thermal spray coating of each of the test pieces of Examples 5 to 9 was colored green, which was considered to be Cr oxide, the surface state was almost the same as the initial state. In addition, when microscopic observation of the cross-section of the thermal spray coating of each of the test pieces of Examples 5 to 9 was performed, minute pitting corrosion was observed in a portion colored green, but corrosion progressed inside the thermal spray coating. No inclusions, such as those formed by corrosion products due to the above, were found.
【００４４】実施例５〜９の各試験片の重量変化、腐食
速度および溶射皮膜の膜厚変化を表２に示し、比較例１
３〜１５の重量変化、腐食速度および腐食孔深さを表３
に示す。なお、腐食孔深さは、焦点深度法による１０点
平均値で求めた。Table 2 shows the change in weight, the corrosion rate, and the change in the thickness of the sprayed coating of each of the test pieces of Examples 5 to 9, and Comparative Example 1
Table 3 shows the weight change, corrosion rate and corrosion hole depth of 3 to 15.
Shown in In addition, the depth of the corrosion hole was determined by a 10-point average value by the depth of focus method.
【００４５】[0045]
【表２】 [Table 2]
【表３】 また、実施例５〜９および比較例１３〜１５の腐食速度
を図３に示す。[Table 3] FIG. 3 shows the corrosion rates of Examples 5 to 9 and Comparative Examples 13 to 15.
【００４６】表２および３、ならびに図３から、実施例
５〜９の腐食減量はほどんどなく、比較例１３〜１５に
比べて耐食性に優れていることが分かる。From Tables 2 and 3, and FIG. 3, it can be seen that the corrosion weight loss of Examples 5 to 9 is negligible and that they are superior to Comparative Examples 13 to 15 in corrosion resistance.
【００４７】実施例１０〜１１および比較例１６ 実際のごみ焼却設備の煙道内周面に、Ｎｉ５０ｗｔ％お
よびＣｒ５０ｗｔ％からなる合金粉末（不可避不純物は
含む）を用いて、ＨＶＯＦにより目標膜厚２００μｍと
して幅２００ｍｍの環状溶射皮膜を全周にわたって形成
した（実施例１０）。また、同じ煙道内周面における実
施例１０の溶射皮膜よりも５００ｍｍ後流側に、Ｎｉ８
０ｗｔ％およびＣｒ２０ｗｔ％からなる合金粉末（不可
避不純物は含む）を用いて、ＨＶＯＦにより目標膜厚２
００μｍとして幅２００ｍｍの環状溶射皮膜を全周にわ
たって形成した（実施例１１）。さらに、同じ煙道内周
面における実施例１１の溶射皮膜よりも５００ｍｍ後流
側に、JIS ＳＵＳ３１６Ｌからなる合金粉末を用いて、
ＨＶＯＦにより目標膜厚２００μｍとして幅２００ｍｍ
の環状溶射皮膜を全周にわたって形成した（比較例１
６）。Examples 10 to 11 and Comparative Example 16 An alloy powder composed of 50 wt% of Ni and 50 wt% of Cr (including unavoidable impurities) was used on the inner peripheral surface of the flue of an actual refuse incineration plant, and the target film thickness was set to 200 μm by HVOF. An annular thermal spray coating having a width of 200 mm was formed over the entire circumference (Example 10). Further, on the inner peripheral surface of the same flue, 500 mm downstream of the thermal sprayed coating of Example 10, Ni8
Using an alloy powder (including unavoidable impurities) composed of 0 wt% and 20 wt% of Cr, the target film thickness 2 was obtained by HVOF.
An annular sprayed coating having a width of 200 mm and a width of 200 mm was formed over the entire circumference (Example 11). Further, on the inner peripheral surface of the same flue, on the downstream side of the thermal sprayed coating of Example 11 by 500 mm, using an alloy powder composed of JIS SUS316L,
The target film thickness is 200 μm and the width is 200 mm by HVOF.
Was formed over the entire circumference (Comparative Example 1).
6).
【００４８】そして、ごみ焼却設備を１年間操業した後
の各溶射皮膜の外観を観察したところ、実施例１０〜１
１の溶射皮膜の表面はほぼ初期状態のままであった。こ
れに対し、比較例１６の溶射皮膜の表面は赤褐色に着色
しており、JIS ＳＵＳ３１６Ｌ中のＦｅ分が腐食したも
のと考えられる。なお、煙道の内周面は赤褐色に着色し
ていた。After observing the appearance of each sprayed coating after operating the refuse incinerator for one year, Examples 10 to 1 were observed.
The surface of the thermal sprayed coating No. 1 remained almost in the initial state. On the other hand, the surface of the thermal spray coating of Comparative Example 16 was colored reddish brown, and it is considered that the Fe component in JIS SUS316L was corroded. The inner peripheral surface of the flue was colored reddish brown.
【００４９】また、ごみ焼却設備を半年間および１年間
操業した後の実施例１０〜１１および比較例１６の溶射
皮膜の各溶射皮膜の膜厚を、流れ方向に所定間隔をおい
た３つの円周上でかつ円周方向に等角度間隔をおいた８
箇所、合計２４箇所で測定したところ、いずれの溶射皮
膜の場合も、半年後も１年後もほとんど変化していなか
った。The thickness of each of the sprayed coatings of Examples 10 to 11 and Comparative Example 16 after operating the refuse incineration facility for half a year and for one year was determined by three circles spaced at predetermined intervals in the flow direction. 8 at equal angular intervals on the circumference and in the circumferential direction
The measurement was performed at 24 points in total, and it was found that there was almost no change in any of the sprayed coatings after half a year or one year.
【図面の簡単な説明】[Brief description of the drawings]
【図１】実施例１〜２および比較例１〜７の各試験片に
おける腐食速度を示すグラフである。FIG. 1 is a graph showing corrosion rates of test pieces of Examples 1 and 2 and Comparative Examples 1 to 7.
【図２】実施例３〜４および比較例８〜１２の各試験片
における腐食速度を示すグラフである。FIG. 2 is a graph showing corrosion rates of test pieces of Examples 3 to 4 and Comparative Examples 8 to 12.
【図３】実施例５〜９および比較例１３〜１５の各試験
片における腐食速度を示すグラフである。FIG. 3 is a graph showing corrosion rates of test pieces of Examples 5 to 9 and Comparative Examples 13 to 15.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 堀田 隆一 大阪市住之江区南港北１丁目７番89号 日 立造船株式会社内 (72)発明者 清水 重雄 大阪市住之江区南港北１丁目７番89号 日 立造船株式会社内 (72)発明者 高橋 虎郎 大阪市住之江区南港北１丁目７番89号 日 立造船株式会社内 Ｆターム(参考） 4K031 AA08 AB09 CB22 CB23 CB24 CB30 DA01 DA06 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ryuichi Hotta 1-7-89 Minami Kohoku, Suminoe-ku, Osaka-shi Inside Tachibashi Shipbuilding Co., Ltd. (72) Inventor Shigeo Shimizu 1- 7-89 Minami Kohoku, Suminoe-ku, Osaka-shi No. Tachibashi Shipbuilding Co., Ltd. (72) Inventor Toro Takahashi 1- 7-89 Minami Kohoku, Suminoe-ku, Osaka City F-Term (in reference) 4K031 AA08 AB09 CB22 CB23 CB24 CB30 DA01 DA06
Claims (5)
に、爆発溶射法または高速ガス炎溶射法により、Ｎｉ８
０〜２０ｗｔ％およびＣｒ１５〜５０ｗｔ％（但し、Ｎ
ｉとＣｒの合計量は６０ｗｔ％以上である）を含み、残
部不可避不純物からなる合金の溶射皮膜を形成すること
を特徴とする露点腐食防止方法。1. An explosion spraying method or a high-speed gas flame spraying method is used to coat Ni8 on the surface of equipment placed in a dew-point corrosion environment.
0-20 wt% and Cr15-50 wt% (however, N
a total amount of i and Cr is 60 wt% or more), and forming a sprayed coating of an alloy comprising the remaining unavoidable impurities.
よびＭｏ５〜１５ｗｔ％のうちの１種または２種を含む
（但し、ＷとＭｏの両者を含む場合の合計量は２０ｗｔ
％以下である）ことを特徴とする請求項１記載の露点腐
食防止方法。2. The alloy further contains one or two of W5 to 15 wt% and Mo5 to 15 wt% (however, the total amount of the alloy containing both W and Mo is 20 wt%).
% Or less).
ｉ２〜５ｗｔ％およびＦｅ２〜５ｗｔ％のうちの１種ま
たは２種以上含む（但し、Ｂ、ＳｉおよびＦｅのうちの
２種以上を含む場合の合計量は６〜８ｗｔ％である）こ
とを特徴とする請求項１または２記載の露点腐食防止方
法。3. The alloy according to claim 1, further comprising B2 to 5 wt%,
It is characterized by containing one or more of i2 to 5 wt% and Fe2 to 5 wt% (however, when two or more of B, Si and Fe are contained, the total amount is 6 to 8 wt%). The method for preventing dew-point corrosion according to claim 1 or 2.
請求項１、２または３記載の露点腐食防止方法。4. The method according to claim 1, wherein the thermal spraying method is a high-speed gas flame thermal spraying method.
ｍである請求項１、２、３または４記載の露点腐食防止
方法。5. The thermal sprayed coating having a thickness of 200 to 500 μm.
5. The method for preventing dew point corrosion according to claim 1, 2, 3, or 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21120598A JP2000045058A (en) | 1998-07-27 | 1998-07-27 | Dew point corrosion preventing method |
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| Application Number | Priority Date | Filing Date | Title |
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| JP21120598A JP2000045058A (en) | 1998-07-27 | 1998-07-27 | Dew point corrosion preventing method |
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| Publication Number | Publication Date |
|---|---|
| JP2000045058A true JP2000045058A (en) | 2000-02-15 |
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| JP21120598A Pending JP2000045058A (en) | 1998-07-27 | 1998-07-27 | Dew point corrosion preventing method |
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| WO2005093113A1 (en) * | 2004-03-25 | 2005-10-06 | Topy Kogyo Kabushiki Kaisha | Metallic glass laminate, process for producing the same and use thereof |
| JP2007131952A (en) * | 2004-03-25 | 2007-05-31 | Akihisa Inoue | Metallic glass laminate member |
| KR100751450B1 (en) * | 2000-12-30 | 2007-08-23 | 주식회사 케이씨씨 | Nontoxic, antifouling paints composition |
| JP2007224377A (en) * | 2006-02-24 | 2007-09-06 | Jfe Steel Kk | Steel material superior in acid-corrosion resistance |
| KR20120055575A (en) * | 2009-07-29 | 2012-05-31 | 페데랄-모굴 부르샤이트 게엠베하 | Sliding member having a thermally sprayed coating and method for producing same |
| WO2013126134A1 (en) * | 2012-02-22 | 2013-08-29 | Chevron U.S.A. Inc. | Coating compositions, applications thereof, and methods of forming |
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- 1998-07-27 JP JP21120598A patent/JP2000045058A/en active Pending
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| Publication number | Priority date | Publication date | Assignee | Title |
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| KR100751450B1 (en) * | 2000-12-30 | 2007-08-23 | 주식회사 케이씨씨 | Nontoxic, antifouling paints composition |
| WO2005093113A1 (en) * | 2004-03-25 | 2005-10-06 | Topy Kogyo Kabushiki Kaisha | Metallic glass laminate, process for producing the same and use thereof |
| JP2007131952A (en) * | 2004-03-25 | 2007-05-31 | Akihisa Inoue | Metallic glass laminate member |
| JP4644653B2 (en) * | 2004-03-25 | 2011-03-02 | 国立大学法人東北大学 | Metal glass laminate |
| JP2007224377A (en) * | 2006-02-24 | 2007-09-06 | Jfe Steel Kk | Steel material superior in acid-corrosion resistance |
| KR20120055575A (en) * | 2009-07-29 | 2012-05-31 | 페데랄-모굴 부르샤이트 게엠베하 | Sliding member having a thermally sprayed coating and method for producing same |
| JP2013500392A (en) * | 2009-07-29 | 2013-01-07 | フェデラル−モーグル ブルシェイド ゲーエムベーハー | Sliding member having thermal spray coating and manufacturing method thereof |
| KR101718840B1 (en) * | 2009-07-29 | 2017-03-22 | 페데랄-모굴 부르샤이트 게엠베하 | Sliding member having a thermally sprayed coating and method for producing same |
| WO2013126134A1 (en) * | 2012-02-22 | 2013-08-29 | Chevron U.S.A. Inc. | Coating compositions, applications thereof, and methods of forming |
| CN113684438A (en) * | 2021-08-31 | 2021-11-23 | 安徽工业大学 | High-strength high-hardness spraying powder for surface protection and application method thereof |
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