CN1329543C - Method for producing oxidation-resistant high Cr ferritic heat resistant steel - Google Patents

Method for producing oxidation-resistant high Cr ferritic heat resistant steel Download PDF

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Publication number
CN1329543C
CN1329543C CNB2003801001783A CN200380100178A CN1329543C CN 1329543 C CN1329543 C CN 1329543C CN B2003801001783 A CNB2003801001783 A CN B2003801001783A CN 200380100178 A CN200380100178 A CN 200380100178A CN 1329543 C CN1329543 C CN 1329543C
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China
Prior art keywords
steel
ferrite
oxidation treatment
minutes
crystal grain
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CNB2003801001783A
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CN1692171A (en
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板垣孟彦
鸟塚史郎
九津见启之
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National Institute for Materials Science
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National Institute for Materials Science
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/002—Heat treatment of ferrous alloys containing Cr
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D7/00—Modifying the physical properties of iron or steel by deformation
    • C21D7/13—Modifying the physical properties of iron or steel by deformation by hot working
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous alloys
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/005—Ferrite

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Other Surface Treatments For Metallic Materials (AREA)
  • Heat Treatment Of Steel (AREA)

Abstract

A high Cr ferritic heat-resistant steel (having a Cr content of 15 mass % or less), which has a deformation texture comprising elongated ferrite grains or a fine crystal grain structure having a ferrite grain diameter of 3 mum or less in the region having a depth from the surface of at least 10 mum, and has a protective film on the surface thereof. The high Cr ferritic heat-resistant steel has an improved resistance to oxidation with no reduction of strength at a high temperature or toughness.

Description

The manufacture method of the high chromium content ferrite class high temperature steel of scale resistance
Technical field
The present application relates to the manufacture method of the ferrite heat resistant steel (ferritic heat-resistantsteel) that uses under the high temperature of thermal power generation stove or chemical industry device etc. and low oxygen partial pressure environment atmosphere.
Background technology
At about 60% of the whole electric power needs of Japan is to be supplied with by the heat power station that uses fossil oil, and combustion of fossil fuel can be discharged a large amount of carbonic acid gas.
On the other hand, from for preventing that global warming from limiting the viewpoint of effective utilization of the discharge of carbonic acid gas and resource energy, the generating efficiency in strong request power station improves.As fuel-burning power plant such high temperature resistant, highly compressed material, use high temperature steel or refractory alloy, when such high temperature steel or refractory alloy use, in atmospheric environment in the oxide film performance of the formed densification in surface function as protective membrane.
Yet in the such high-temperature water vapor of thermal power generation stove, under the low oxygen partial pressure environment, the supply of oxygen is insufficient, can not form the protective membrane of oxide compound, becomes big so compare oxidative damage with the device that uses in atmospheric environment.
Generally, even the content of Cr contains Cr high temperature steel or refractory alloy under the high-temperature water vapor environment more than 25 quality %,, has good scale resistance owing to can form the protective membrane of scale resistance.
In addition, the content of Cr contains high temperature steel or refractory alloy about 20 quality %, can or make the substrate surface improvement by the such mechanical treatment of shot peening, perhaps forms the protective membrane of scale resistances by methods such as crystal grain miniaturizations.
Yet the high Cr ferrite heat resistant steel of the content of Cr below 15 quality % because the amount of Cr is few, can not fully be supplied with the necessary Cr oxide compound of protective membrane that forms scale resistance.Therefore, the method of the scale resistance of the high Cr ferrite heat resistant steel of content below 15 quality % of the Cr of conduct improvement up to the present, attempted or increased chromium (Cr) or silicon (Si), (for example perhaps add palladium (Pd) or platinum (Pt) etc., referring to document 1-4), but can not avoid or cause the reduction of material, perhaps because the high price that interpolation palladium (Pd) or platinum elements such as (Pt) cause.The content that makes Cr for example makes at the effective ways of the scale resistance improvement of the high Cr ferrite heat resistant steel of 9～12 quality % and does not also realize below 15 quality %.
Document 1: the spy opens the 2002-69531 communique
Document 2: the spy opens the 2001-192730 communique
Document 3: the spy opens flat 11-61342 communique
Document 4: the spy opens flat 10-287960 communique
The present application is finished in view of the above fact, has solved the prior art problems point, even be problem with the high Cr jessop that the protective membrane that has formed scale resistance under the low oxygen partial pressure environment in high-temperature water vapor is provided.
Summary of the invention
The present application in order to solve above-mentioned problem, provides invention as described below.
Promptly; the present application; the 1st; the ferrite heat resistant steel of content below 15 quality % of Cr is provided; at least be worked structure or the micro organization of ferritic particle diameter below 3 μ m that constitutes by the ferrite crystal grain (ferritic grains) that has extended in the scope of case depth 10 μ m, the steel of protective membrane is arranged on the surface.And, the 2nd, the steel of minor axis below 5 μ m of the ferrite crystal grain that it is characterized in that extending be provided, the 3rd, the minor axis that the ferrite crystal grain that has extended is provided below the 3 μ m, the steel of particle diameter below 1 μ m of ferrite crystal grain.
The present application, the 4th, the manufacture method of the steel of claim 1～3 is provided, to process 400～800 ℃ scope, the scope of surperficial at least 10 μ m forms worked structure or fine ferrite grain structure, carries out pre-oxidation treatment, forms protective membrane.The 5th, the degree of finish true strain that adds man-hour is in the manufacture method more than 0.7.The 6th, the temperature that is provided in the atmospheric environment gas at 400～800 ℃ keeps carrying out in 30 minutes～90 minutes the manufacture method of pre-oxidation treatment.
Brief description of drawings
Fig. 1: be after 500 ℃ the compression process in temperature, in atmosphere, carry out the pre-oxidation treatment of 640 ℃/1h after, carry out the section SEM photo of forcing the Ministry of worker behind the steam oxidation of 650 ℃/100h
Fig. 2: be after 500 ℃ the compression process in temperature, in atmosphere, carry out the pre-oxidation treatment of 640 ℃/1h after, carry out behind the steam oxidation of 650 ℃/100h a little less than add the section SEM photo of the Ministry of worker
Fig. 3 is the section SEM photo of forcing the Ministry of worker that does not carry out after 500 ℃ the compression process after pre-oxidation treatment is carried out the steam oxidation of 650 ℃/3h in temperature
Embodiment
The present application has aforesaid feature, below its embodiment is described.
Notable attribute is that the present application is in high-temperature water vapor or in the low oxygen partial pressure environment gas, when the scale resistance of the high Cr ferrite heat resistant steel of content below 15 quality % of improveing Cr, do not increase the composition of chromium (Cr) or silicon (Si), perhaps do not add palladium (Pd) or the such element of platinum (Pt), by specific processing or thermal treatment improvement scale resistance.Therefore, the high Cr jessop that obtains with the scale resistance improved method of the present application has not influence and forms the original physical property or the advantage of chemical property.
Generally; when the content of Cr surpasses 15 quality %; as previously mentioned; make the upper layer upgrading of steel by carrying out mechanical treatments such as shot peening; perhaps handle by the bigger crystal grain miniaturization of carrying out about particle diameter 10～50 μ m; can generate the protective membrane of scale resistance, but the high Cr ferrite heat resistant steel of the content of Cr below 15 quality %, even carry out the protective membrane that above-mentioned processing can not form scale resistance.Why saying so is because the amount of content below 15 quality % of Cr, even the crystal grain miniaturization of carrying out about particle diameter 10～50 μ m is handled, forming with Cr2O3 is that the necessary Cr of protective membrane of principal constituent can not be fully and diffusion equably.Therefore, in high-temperature water vapor, can not form the protective membrane of scale resistance.
Therefore, what the present application was primary is high Cr ferrite heat resistant steel to be carried out high temperature force the worker, and the strain energy height is accumulated, and the following micro organization of crystallization particle diameter 2 μ m is formed.As the reason that the strain energy height of the present application is accumulated or the micro organization below the crystallization particle diameter 3 μ m is formed, the steel easy recrystallization that the strain energy height has been accumulated forms the submicron-sized particulate tissue.And along with the formation of this submicron-sized particulate tissue, the grain interfacial area increases, and it is to promoting chromium (Cr) diffusion useful.And, because the impartial diffusion of this chromium (Cr) has formed chromated oxide (Cr2O3), as the protective membrane performance function of scale resistance.The present application is that the strain energy height is accumulated like this.In addition, the following submicron-sized particulate tissue of particle diameter 3 μ m that forms ferrite crystal grain can be described as a kind of mode of the strain energy of highly having accumulated.
Strain energy height in the present application is accumulated or the following micro organization of ferrite crystallization particle diameter 3 μ m is formed, can not form with processing thermal treatments such as steel rolling of adopting usually or forgings.For the strain energy height being accumulated or formed fine crystalline grain tissue below the crystallization particle diameter 3 μ m, expectation carries out that rate of straining 0.1sec-1 is above, the high temperature process processing of working modulus (section decrement) 70% or more.Under the situation of working modulus discontented 70%, accumulating of desired strain energy is insufficient, even carry out generation and its use that pre-oxidation treatment can not be expected protective membrane.
In addition, forcing the worker about high temperature preferably carries out 400～800 ℃ temperature range.And, under such condition, form strain and can make the ferrite crystal grain of elongation or the generation of particulate become possibility.
The form of the ferrite crystal grain that has extended, minor axis are below 5 μ m, and preferred especially minor axis is below the 3 μ m.Perhaps the particle diameter of ferrite crystal grain is below 3 μ m, the special particulate of preferable particle size below 1 μ m.
The present application is to force the worker strain energy height is accumulated by so high Cr ferrite heat resistant steel being carried out high temperature; the following micro organization of crystallization particle diameter 3 μ m is formed; force the worker and strain energy is accumulated or formed the fine crystalline tissue even carry out high temperature, only this can not form protective membrane in high-temperature water vapor.It is necessary then by pre-oxidation treatment protective membrane being generated.Pre-oxidation treatment in atmospheric environment or contain in rare gas element (rare gas element or the nitrogen) environment of oxygen and carry out, is actual in atmospheric environment preferably.And, pre-oxidation treatment preferably in this atmospheric environment 400～800 ℃ of heat treated of carrying out about 30～90 minutes.
By making up this thermal treatment, make chromium (Cr) oxidation, form Cr as scale resistance protective membrane performance function 2O 3
The relation in Heating temperature and average crystal grain footpath in the pre-oxidation treatment confirms that the heating below 660 ℃ in atmospheric environment gas keeps test portion below 0.8 μ m, and 680～700 ℃ heating keeps test portion at 1～2 μ m.
By the present application, make the high Cr ferrite heat resistant steel of content below 15 quality % of the Cr of the protective membrane that can not form scale resistance till now can form the protective membrane of scale resistance, significantly enlarged the purposes of high Cr ferrite heat resistant steel.And the present application has been utilized thermal treatment, has the advantage that any variation does not take place the composition that makes high Cr ferrite heat resistant steel.And formed protective membrane approaches the binding property height, is difficult to peel off, and makes pipe blocking so have the dirt of peeling off, perhaps the effect that significantly reduces of the danger of turbine slurry wearing and tearing.
In addition, the material that contains the various compositions of contained Cr below 15 quality % in the high Cr ferrite heat resistant steel of the object of the present application.For example, containing Cr is 7～15 quality %.
Contain steel, for example the high Cr jessop of stipulating among ASME SA335 P91 or ASME SA 213 T91.With its general name, be defined as high ferrite " class " in the present application.
Embodiment
＜embodiment 〉
With the Mod.9Cr-1Mo steel 500 ℃ carry out 70% compression process after, cut off, grind, make micro organization zone and worked structure zone be exposed to the surface, after carrying out the pre-oxidation treatment of 1h under 650 ℃, the section SEM photo of forcing the Ministry of worker that this test film carries out behind the steam oxidation of 650 ℃/100h is Fig. 1 in atmospheric environment gas.Affirmation has generated chromium trioxide (Cr on the surface 2O 3) protective membrane (thickness 0.1 μ m following).In addition, the crystallization particle diameter of the ferrite crystal grain in the micro organization zone under the protective membrane is below 1.0 μ m.In addition, the elongation ferrite minor axis in the worked structure zone under the protective membrane is 3 μ m.
＜comparative example 1 〉
The Mod.9Cr-1Mo steel is carried out the steam oxidation of 650 ℃/100h after the pre-oxidation treatment of carrying out 1h under 680 ℃ in atmosphere.Fig. 2 is that the SEM of its section takes a picture, and promote the oxidation has taken place, and 2 layers of dirt of ferric oxide (the about 60 μ m of thickness) look thick.The average crystallite particle diameter of ferrite crystal grain is 7 μ m.
By the contrast of this example and embodiment, confirm to accumulate or the formation of fine crystalline tissue is necessary for the strain energy that formation has a protective membrane height of water-fast steam oxidation.
＜comparative example 2 〉
With method similarly to Example 1, with the Mod.9Cr-1Mo steel 500 ℃ carry out 70% compression process after, do not carry out pre-oxidation treatment, test film is carried out observing at the steam oxidation of 650 ℃/3h.Fig. 3 is that the section SEM that forces the Ministry of worker of this moment takes a picture.Confirm to have formed 2 layers of dirt (thick about 10 μ m).
As above detailed description, according to the present application, impossible Cr content of making over can form the good oxygen-proof film of thin binding property at the high Cr ferritic steel below 15%.

Claims (6)

1. steel; the ferrite heat resistant steel of content below 15 quality % that it is characterized in that Cr; at least be worked structure or the micro organization of ferritic particle diameter below 3 μ m that constitutes by the ferrite crystal grain that has extended in the scope of case depth 10 μ m; on the surface protective membrane is arranged, the minor axis of the ferrite crystal grain that has extended is below the 5 μ m.
2. steel according to claim 1, wherein, the minor axis of the ferrite crystal grain that has extended below the 3 μ m or ferritic particle diameter below the 1 μ m.
3. the manufacture method of claim 1 or 2 described steel; it is characterized in that processing 400～800 ℃ scope; at least the scope of surperficial 10 μ m forms worked structure or fine ferrite grain structure; carry out pre-oxidation treatment; form protective membrane, described pre-oxidation treatment is meant in atmospheric environment or contains in the environment of rare gas element of oxygen 400～800 ℃ of heat treated of carrying out 30～90 minutes.
4. manufacture method according to claim 3 is characterized in that adding the degree of finish true strain in man-hour more than 0.7.
5. manufacture method according to claim 3, it is characterized in that carrying out pre-oxidation treatment is that the temperature at 400～800 ℃ kept 30 minutes～90 minutes in atmospheric environment gas.
6. manufacture method according to claim 4, it is characterized in that carrying out pre-oxidation treatment is that the temperature at 400～800 ℃ kept 30 minutes～90 minutes in atmospheric environment gas.
CNB2003801001783A 2002-11-01 2003-11-04 Method for producing oxidation-resistant high Cr ferritic heat resistant steel Expired - Fee Related CN1329543C (en)

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JP2002320568A JP4253719B2 (en) 2002-11-01 2002-11-01 Manufacturing method of oxidation resistant high Cr ferritic heat resistant steel
JP320568/2002 2002-11-01

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CN1329543C true CN1329543C (en) 2007-08-01

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EP (1) EP1557477B1 (en)
JP (1) JP4253719B2 (en)
KR (1) KR100619158B1 (en)
CN (1) CN1329543C (en)
DE (1) DE60325995D1 (en)
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WO (1) WO2004040031A1 (en)

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US9847520B1 (en) * 2012-07-19 2017-12-19 Bloom Energy Corporation Thermal processing of interconnects
DE102018217284A1 (en) * 2018-10-10 2020-04-16 Siemens Aktiengesellschaft Improvement of the low temperature oxidation resistance of chrome steel, component and process

Citations (1)

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Publication number Priority date Publication date Assignee Title
JPH07268554A (en) * 1994-03-28 1995-10-17 Nippon Steel Corp Ferritic stainless steel for automobile exhaust system excellent in formability and heat resistance

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US4331474A (en) * 1980-09-24 1982-05-25 Armco Inc. Ferritic stainless steel having toughness and weldability
JPH09143611A (en) * 1995-11-21 1997-06-03 Nippon Steel Corp Hot rolled high strength steel sheet excellent in formability and fatigue characteristic and having thermal softening resistance
EP0903413B1 (en) * 1997-09-22 2004-04-14 National Research Institute For Metals Fine-grained ferrite-based structural steel and manufacturing process of this steel
EP0903421B1 (en) * 1997-09-22 2004-11-24 National Research Institute For Metals Ferritic heat-resistant steel and method for producing it
JP4221518B2 (en) * 1998-08-31 2009-02-12 独立行政法人物質・材料研究機構 Ferritic heat resistant steel
JP4355782B2 (en) * 1999-02-26 2009-11-04 独立行政法人物質・材料研究機構 Ferritic heat resistant steel with improved oxidation resistance
JP2001192730A (en) * 2000-01-11 2001-07-17 Natl Research Inst For Metals Ministry Of Education Culture Sports Science & Technology HIGH Cr FERRITIC HEAT RESISTANT STEEL AND ITS HEAT TREATMENT METHOD
EP1205570A4 (en) * 2000-03-02 2004-11-10 Matsushita Electric Ind Co Ltd Color crt mask frame, steel plate for use therein, process for producing the steel plate, and color crt having the frame
EP1225242B1 (en) * 2001-01-18 2004-04-07 JFE Steel Corporation Ferritic stainless steel sheet with excellent workability and method for making the same

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07268554A (en) * 1994-03-28 1995-10-17 Nippon Steel Corp Ferritic stainless steel for automobile exhaust system excellent in formability and heat resistance

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EP1557477A1 (en) 2005-07-27
DK1557477T3 (en) 2009-05-18
WO2004040031A1 (en) 2004-05-13
US20040250923A1 (en) 2004-12-16
KR20040089657A (en) 2004-10-21
CN1692171A (en) 2005-11-02
KR100619158B1 (en) 2006-08-31
JP2004156075A (en) 2004-06-03
EP1557477A4 (en) 2006-05-03
JP4253719B2 (en) 2009-04-15
DE60325995D1 (en) 2009-03-12
EP1557477B1 (en) 2009-01-21

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