CN109355571B - Ferrite heat-resistant stainless steel and preparation method thereof - Google Patents
Ferrite heat-resistant stainless steel and preparation method thereof Download PDFInfo
- Publication number
- CN109355571B CN109355571B CN201811452857.1A CN201811452857A CN109355571B CN 109355571 B CN109355571 B CN 109355571B CN 201811452857 A CN201811452857 A CN 201811452857A CN 109355571 B CN109355571 B CN 109355571B
- Authority
- CN
- China
- Prior art keywords
- stainless steel
- temperature
- resistant stainless
- heat
- time
- 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.)
- Active
Links
Images
Classifications
-
- 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
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/076—Use of slags or fluxes as treating agents
-
- 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
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips 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
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
-
- 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
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
-
- 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
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- 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
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
-
- 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
-
- 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
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Abstract
The invention discloses ferrite heat-resistant stainless steel and a preparation method thereof. The ferrite heat-resistant stainless steel comprises the following chemical components in percentage by weight: c: 0.06-0.11%, Si: 0.7-1.2%, Mn: 0.6-1.0%, Cr: 17.0-19.0%, Al: 0.7-1.2%, N: 0.005-0.015% and the balance of Fe and inevitable impurities. According to the ferrite heat-resistant stainless steel and the preparation method thereof, Al and N are added, so that the high-temperature oxidation resistance of the stainless steel can be improved, and meanwhile, the contents of C, Si, Mn, P, S and Cr are adjusted and controlled, so that the ferrite heat-resistant stainless steel with excellent high-temperature oxidation resistance, impact toughness, low expansion coefficient and welding performance can be produced.
Description
Technical Field
The invention relates to the technical field of stainless steel preparation, in particular to ferrite heat-resistant stainless steel and a preparation method thereof.
Background
With the continuous development of thermal power units, the existing thermal power units are mainly high-capacity and high-efficiency thermal power units, and usually ultra-supercritical units with the power of 1000MV or more. In a thermal power generating unit, a boiler is one of the most important components, and the performance of the boiler plays an extremely important role in the safe and economic operation of the whole power plant. The boiler in the thermal power generating unit comprises a superheater, a reheater, a water wall, a header pipeline and corresponding connecting pieces, the structure of the boiler is complex, and a large amount of steel is consumed. At present, boiler tubes such as a superheater and a reheater of different temperature sections of a 600 ℃ parameter boiler are made of mature materials, and the performance basically meets the use requirement, but connecting pieces such as hangers and the like among the boiler tubes need to bear the erosion of high-temperature coal ash at the temperature of over 1000 ℃ due to the fact that the connecting pieces are in direct contact with a hearth, and the connecting pieces are required to have excellent high-temperature oxidation resistance, impact toughness, low expansion coefficient and welding performance.
Chinese patent publication No. CN105256247B entitled "ferritic heat-resistant steel for coal-fired thermal power generation boiler pipes and valve castings" discloses a ferritic heat-resistant steel which is improved in strength and high-temperature corrosion resistance by adding a small amount of elements such as Ni, Mn, Mo, and Al on the basis of conventional ferritic heat-resistant steel T91, but is poor in oxidation resistance when used at a temperature of 1000 ℃.
Chinese patent publication No. CN105506489A entitled "high temperature oxidation resistant ferritic heat resistant stainless steel and manufacturing method thereof" discloses a ferritic heat resistant stainless steel, which adopts Cr18 system, and simultaneously increases rare earth elements to improve the high temperature oxidation resistance of steel by adjusting the C content in the steel, adds Nb and W elements to ensure the high temperature mechanical property strength of steel, and adds Ti to improve weldability, however, in order to reduce the casting difficulty, the structure of the oxide film of the ferritic heat resistant stainless steel is unstable in high temperature use environment, and the oxidation resistance is poor.
Chinese patent publication No. CN103131951A entitled "ferritic heat resistant steel" discloses a ferritic heat resistant steel whose oxidation resistance and strength are improved by increasing Cr to about 13% and adding W, Co, Mo, Nb, V and other elements in combination to 9Cr steel, but W, Co and Mo are expensive and easily form harmful precipitation phases during processing and use, resulting in rapid deterioration of performance.
Therefore, it is necessary to provide a ferritic heat-resistant stainless steel having excellent high-temperature oxidation resistance, impact toughness, a low expansion coefficient and weldability under a high-temperature environment to meet the use requirements of boilers.
Disclosure of Invention
In order to solve the technical problems in the prior art, the invention provides ferrite heat-resistant stainless steel and a preparation method thereof.
Therefore, the invention discloses a ferrite heat-resistant stainless steel. The ferrite heat-resistant stainless steel comprises the following chemical components in percentage by weight:
c: 0.06-0.11%, Si: 0.7-1.2%, Mn: 0.6-1.0%, Cr: 17.0-19.0%, Al: 0.7-1.2%, N: 0.005-0.015% and the balance of Fe and inevitable impurities.
Further, in the ferritic heat-resistant stainless steel, the ferritic heat-resistant stainless steel comprises the following chemical components in percentage by weight:
c: 0.07 to 0.09%, Si: 0.8 to 1.0%, Mn: 0.7-0.9%, Cr: 17.5-18.5%, Al: 0.8-1.1%, N: 0.007-0.012%, and the balance of Fe and inevitable impurities.
In addition, the invention also discloses a preparation method of the ferrite heat-resistant stainless steel for manufacturing the ferrite heat-resistant stainless steel. The preparation method comprises the following steps:
1) smelting
Molten steel which meets the components of the ferrite heat-resistant stainless steel is smelted by adopting molten iron pretreatment, K-OBM-S, VOD refining and LF process in sequence;
wherein: the temperature of the molten steel after the molten iron pretreatment is 1250-1350 ℃;
argon is blown in the K-OBM-S whole process, the tapping temperature is 1650-1690 ℃, and the thickness of ladle slag is 30-80 mm;
in the VOD refining, the boiling time is 12-18 min, and the reduction time is 15-20 min;
the LF refining slag system comprises the following components in percentage by weight: CaO: not less than 60% of Al2O3：≥30％，SiO2：≤1％；
In the LF, feeding a silicon-calcium wire 5min before weak stirring, wherein the feeding amount of the silicon-calcium wire is 3-4 m/ton, the weak stirring time is 15min, the total LF treatment time is over 45min, and the tapping temperature is 1560-1580 ℃;
2) continuous casting
Before molten steel is poured, argon is adopted to empty air in a tundish, and argon is blown in the whole process in the continuous casting process;
3) casting blank grinding
Finishing the hot grinding, cutting and sizing of the surface of the casting blank at the temperature of more than 400 ℃;
4) hot rolling
Controlling the charging temperature of the blank to be more than 250 ℃ before hot rolling, wherein the hot rolling heating temperature is 1160-1220 ℃, the heating time is 0.8-1.2min/mm, and the hot rolling finishing temperature is 750-800 ℃;
5) thermal treatment
The heating temperature of the heat treatment is 800-850 ℃, the heat preservation time is 4-5 min/mm, and the discharging process adopts air cooling.
Further, in the preparation method of the ferrite heat-resistant stainless steel, in the VOD refining, stirring is carried out after aluminum is added for the last time, and the stirring time is 5-8 min.
Further, in the preparation method of the ferrite heat-resistant stainless steel, electromagnetic stirring is started in the continuous casting, and the electromagnetic stirring parameter is 900-1100A.
Further, in the method for producing a ferritic heat-resistant stainless steel, the amount of rolling deformation in the hot rolling is set in accordance with actual rolling equipment.
Further, in the method for producing ferritic heat-resistant stainless steel, the single pass rolling deformation amount is 18% or more.
Further, in the preparation method of the ferrite heat-resistant stainless steel, the single-pass rolling deformation amount is 18-28%.
The technical scheme of the invention has the following main advantages:
according to the ferrite heat-resistant stainless steel and the preparation method thereof, provided by the invention, Al and N are added, so that the high-temperature oxidation resistance of the stainless steel can be improved, and meanwhile, the contents of C, Si, Mn and Cr are adjusted and controlled, so that the ferrite heat-resistant stainless steel with excellent high-temperature oxidation resistance, impact toughness, low expansion coefficient and welding performance can be produced, and the ferrite heat-resistant stainless steel can be used for manufacturing a boiler connecting piece of an ultra-supercritical thermal power generating unit.
Drawings
The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:
FIG. 1 is a microstructure diagram of a ferrite heat-resistant stainless steel plate product obtained in example 1 of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the specific embodiments of the present invention and the accompanying drawings. It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.
The technical scheme provided by the embodiment of the invention is described in detail below with reference to the accompanying drawings.
The embodiment of the invention provides ferrite heat-resistant stainless steel which comprises the following chemical components in percentage by weight:
c: 0.06-0.11%, Si: 0.7-1.2%, Mn: 0.6-1.0%, Cr: 17.0-19.0%, Al: 0.7-1.2%, N: 0.005-0.015% and the balance of Fe and inevitable impurities.
Preferably, the ferritic heat-resistant stainless steel can also comprise the following chemical components in percentage by weight:
c: 0.07 to 0.09%, Si: 0.8 to 1.0%, Mn: 0.7-0.9%, Cr: 17.5-18.5%, Al: 0.8-1.1%, N: 0.007-0.012%, and the balance of Fe and inevitable impurities.
In the composition design of the ferritic heat-resistant stainless steel provided by the embodiment of the invention, the range of each alloy element is defined as follows:
c: c may form with alloying elements in the steel, e.g. M23C6And M7C3The carbide of (2) further plays a role of precipitation strengthening, and can improve the high-temperature strength and toughness, and the plasticity and toughness are correspondingly reduced, but when the content of C is too high, the oxidation resistance and the welding performance are reduced due to coarsening of the carbide. Therefore, the content of C in the ferritic heat-resistant stainless steel provided by the embodiment of the invention is limited to 0.06-0.11%, and preferably 0.07-0.09%.
Si: si is an element capable of strengthening ferrite, can contact with oxygen at high temperature to form oxide with a spinel structure, can be tightly combined with a matrix, can improve the heat resistance of the stainless steel, can improve the high-temperature oxidation resistance of the stainless steel, and simultaneously has the deoxidation effect, but the excessive Si content can promote the precipitation of harmful phases, reduce the toughness and is unfavorable for the welding performance. Therefore, the content of Si in the ferritic heat-resistant stainless steel provided by the embodiment of the present invention is limited to 0.7 to 1.2%, and preferably 0.8 to 1.0%.
Mn: mn is added as a deoxidizing agent and a desulfurizing agent during smelting, so that the purity can be greatly improved, and simultaneously the Mn can form a solid solution with Fe, so that the strength and the hardness of steel are improved, but when the addition amount is too large, the hot workability and the welding performance of stainless steel are influenced. Therefore, the Mn content provided by the embodiment of the invention is limited to 0.6-1.0%, preferably 0.7-0.9%.
Cr: cr is the most important ferrite forming element, and Cr can react with oxygen at high temperature to generate Cr2O3, so that further invasion of external oxygen is prevented, and the high-temperature oxidation resistance of the stainless steel can be greatly improved. Therefore, the content of Cr in the ferritic heat-resistant stainless steel provided by the embodiment of the invention is limited to 17-19%, and preferably 17.5-18.5%.
Al: al can form compact and firm Al2O3 at high temperature, has no volatility, is tightly combined with a Cr2O3 oxidation film to form a composite oxidation film, and can greatly enhance the high-temperature oxidation resistance of the material. Meanwhile, AlN generated by combining Al with N in the steel has higher stability during heating, the overheating tendency of the steel is weakened, and the oxidation resistance of the material is improved. However, too high Al content results in severe deterioration of impact toughness and weldability of the material. Therefore, the Al content is limited to 0.7 to 1.2%, preferably 0.8 to 1.1%.
N: n and Al can form a strengthening phase AlN together, the high-temperature oxidation resistance can be improved by adding a small amount of N, but the toughness is reduced by excessive N, and the processing difficulty is increased. Therefore, the N content is limited to 0.005 to 0.015%, preferably 0.007 to 0.012%.
In addition, the embodiment of the invention also provides a preparation method of the ferritic heat-resistant stainless steel for manufacturing the ferritic heat-resistant stainless steel, which comprises the following steps:
11) smelting
The ferrite heat-resistant stainless steel comprises the following chemical components in percentage by weight: c: 0.06-0.11%, Si: 0.7-1.2%, Mn: 0.6-1.0%, Cr: 17.0-19.0%, Al: 0.7-1.2%, N: 0.005-0.015 percent of Fe and inevitable impurities in balance, and smelting molten steel which meets the components of the ferrite heat-resistant stainless steel by adopting molten iron pretreatment, K-OBM-S, VOD refining and LF process in sequence;
wherein: the temperature of molten steel after the molten iron pretreatment is 1250-1350 ℃;
blowing argon in the whole K-OBM-S process, wherein the tapping temperature is 1650-1690 ℃, and the thickness of ladle slag is 30-80 mm;
in VOD refining, boiling time is 12-18 min, and reduction time is 15-20 min;
the LF refining slag system comprises the following components in percentage by weight: CaO: not less than 60%, Al2O 3: not less than 30%, SiO 2: less than or equal to 1 percent;
in LF, feeding a calcium silicon wire 5min before weak stirring, wherein the feeding amount of the calcium silicon wire is 3-4 m/ton, the weak stirring time is 15min, the total LF treatment time is more than 45min, and the tapping temperature is 1560-1580 ℃;
12) continuous casting
Before molten steel is poured, argon is adopted to empty air in a tundish, and argon is blown in the whole process in the continuous casting process;
13) casting blank grinding
Finishing the hot grinding, cutting and sizing of the surface of the casting blank at the temperature of more than 400 ℃;
14) hot rolling
The charging temperature of the blank before hot rolling is controlled to be more than 250 ℃, the heating temperature of hot rolling is 1160-1220 ℃, the heating time is 0.8-1.2min/mm, and the final rolling temperature of hot rolling is 750-800 ℃;
15) thermal treatment
The heating temperature of the heat treatment is 800-850 ℃, the heat preservation time is 4-5 min/mm, and the discharging process adopts air cooling.
Further, in the VOD refining, stirring is carried out after aluminum is added for the last time, and the stirring time is 5-8 min.
In continuous casting, electromagnetic stirring is started, and the electromagnetic stirring parameters are 900-1100A.
In hot rolling, the single-pass rolling deformation is set according to actual rolling equipment. Specifically, the single-pass rolling deformation is 18% or more, preferably 18 to 28%.
The following description is given with reference to specific examples and comparative examples
The compositions of examples and comparative examples of ferritic heat-resistant stainless steels according to the invention are given in table 1.
Wherein the comparative steel grade is 1Cr6Si2 Mo.
TABLE 1 (ingredient table, unit is weight percent)
| Composition (I) | C | Si | Mn | P | S | Cr | Al | N | Mo |
| Example 1 | 0.110 | 0.70 | 1.00 | 0.016 | 0.001 | 17.0 | 0.70 | 0.007 | |
| Example 2 | 0.060 | 0.79 | 0.85 | 0.014 | 0.001 | 17.5 | 0.78 | 0.005 | |
| Example 3 | 0.071 | 0.82 | 0.74 | 0.013 | 0.001 | 18.4 | 0.86 | 0.008 | |
| Example 4 | 0.093 | 1.05 | 0.69 | 0.015 | 0.001 | 19.0 | 1.02 | 0.010 | |
| Example 5 | 0.088 | 0.91 | 0.79 | 0.016 | 0.001 | 17.8 | 0.92 | 0.009 | |
| Example 6 | 0.102 | 1.20 | 0.60 | 0.014 | 0.001 | 18.2 | 1.20 | 0.012 | |
| Comparative example | 0.072 | 1.70 | 0.40 | 0.025 | 0.003 | 5.80 | 0.51 |
FIG. 1 is a microstructure diagram of a ferrite heat-resistant stainless steel plate product obtained in example 1 of the present invention.
The specific preparation methods of the ferritic heat-resistant stainless steel of the above examples and the comparative example are as follows:
the method comprises the steps of smelting a continuous casting blank by adopting molten iron pretreatment → K-OBM-S → VOD refining → a ladle refining furnace (LF) → continuous casting process, finishing the processes of surface hot grinding, cutting, sizing and the like at a temperature of more than 400 ℃ after the continuous casting blank is taken out of a continuous casting machine, then carrying out hot rolling, setting the charging temperature of the blank to be about 320 ℃, the heating temperature to be 1160-1220 ℃, the heating time to be 0.8-1.2min/mm according to the thickness of the blank, setting the final rolling temperature to be 750-800 ℃, setting the deformation amount of single-pass rolling to be 18-28%, carrying out heat treatment after the hot rolling is finished, setting the heat treatment temperature to be 800-850 ℃, setting the heat preservation time to be 4-5 min/mm.
The steel sheets of specifications including 6mm, 8mm, 10mm, 12mm, 15mm, 18mm, 20mm and the like can be produced by the above production method.
The room temperature mechanical property test is carried out on the finished products obtained in the examples and the comparative examples of the ferrite heat-resistant stainless steel of the invention, and the test results are shown in table 2.
Table 2 (Room temperature mechanical property meter)
The finished products obtained in the examples of the ferritic heat-resistant stainless steel of the present invention and the comparative examples were subjected to a high-temperature oxidation resistance test, and the test results are shown in table 3.
TABLE 3 (high temperature oxidation resistance table)
Therefore, the room-temperature mechanical property and the high-temperature oxidation resistance of the ferritic heat-resistant stainless steel provided by the embodiment of the invention are obviously superior to those of a comparative example.
According to the ferrite heat-resistant stainless steel and the preparation method thereof provided by the embodiment of the invention, Al and N are added, so that the high-temperature oxidation resistance of the stainless steel can be improved, and meanwhile, the contents of C, Si, Mn, P, S and Cr are adjusted and controlled, so that the ferrite heat-resistant stainless steel with excellent high-temperature oxidation resistance, impact toughness, low expansion coefficient and welding performance can be produced.
It is noted that, in this document, relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. In addition, "front", "rear", "left", "right", "upper" and "lower" in this document are referred to the placement states shown in the drawings.
Finally, it should be noted that: the above examples are only for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (6)
1. A preparation method of ferritic heat-resistant stainless steel comprises the following chemical components in percentage by weight: 0.06-0.11%, Si: 0.7-1.2%, Mn: 0.6-1.0%, Cr: 17.0-19.0%, Al: 0.7-1.2%, N: 0.005-0.015%, and the balance of Fe and unavoidable impurities, characterized in that the method comprises the following steps:
1) smelting
Molten steel which meets the chemical composition is smelted by adopting molten iron pretreatment, K-OBM-S, VOD refining and LF process in sequence;
wherein:
the temperature of the molten steel after the molten iron pretreatment is 1250-1350 ℃;
argon is blown in the K-OBM-S whole process, the tapping temperature is 1650-1690 ℃, and the thickness of ladle slag is 30-80 mm;
in the VOD refining, the boiling time is 12-18 min, and the reduction time is 15-20 min;
the LF refining slag system comprises the following components in percentage by weight: CaO: not less than 60% of Al2O3：≥30％，SiO2：≤1％；
In the LF, feeding a silicon-calcium wire 5min before weak stirring, wherein the feeding amount of the silicon-calcium wire is 3-4 m/ton, the weak stirring time is 15min, the total LF treatment time is over 45min, and the tapping temperature is 1560-1580 ℃;
2) continuous casting
Before molten steel is poured, argon is adopted to empty air in a tundish, and argon is blown in the whole process in the continuous casting process;
3) casting blank grinding
Finishing the hot grinding, cutting and sizing of the surface of the casting blank at the temperature of more than 400 ℃;
4) hot rolling
Controlling the charging temperature of the blank to be more than 250 ℃ before hot rolling, wherein the hot rolling heating temperature is 1160-1220 ℃, the heating time is 0.8-1.2min/mm, and the hot rolling finishing temperature is 750-800 ℃;
5) thermal treatment
The heating temperature of the heat treatment is 800-850 ℃, the heat preservation time is 4-5 min/mm, and the discharging process adopts air cooling.
2. The method for preparing ferritic heat-resistant stainless steel according to claim 1, wherein the VOD refining is performed by stirring after aluminum is added for the last time, and the stirring time is 5 to 8 min.
3. The method for preparing ferritic heat-resistant stainless steel according to claim 1, wherein in the continuous casting, electromagnetic stirring is started, and electromagnetic stirring parameters are 900 to 1100A.
4. The method according to claim 1, wherein the amount of deformation in the hot rolling is set by a single pass rolling in accordance with actual rolling equipment.
5. The method according to claim 4, wherein the single pass rolling deformation is 18% or more.
6. The method of claim 5, wherein the single pass rolling deformation is 18-28%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811452857.1A CN109355571B (en) | 2018-11-30 | 2018-11-30 | Ferrite heat-resistant stainless steel and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811452857.1A CN109355571B (en) | 2018-11-30 | 2018-11-30 | Ferrite heat-resistant stainless steel and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109355571A CN109355571A (en) | 2019-02-19 |
| CN109355571B true CN109355571B (en) | 2020-12-04 |
Family
ID=65330330
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811452857.1A Active CN109355571B (en) | 2018-11-30 | 2018-11-30 | Ferrite heat-resistant stainless steel and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109355571B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114574767A (en) * | 2022-03-11 | 2022-06-03 | 江苏铭展特钢制造有限公司 | High-temperature-resistant stainless steel bar for automobile parts and processing technology thereof |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4173609B2 (en) * | 1999-09-16 | 2008-10-29 | 日新製鋼株式会社 | Austenitic stainless steel and steel plate for press forming with excellent formability and hot workability |
| JP6205407B2 (en) * | 2013-03-06 | 2017-09-27 | 新日鐵住金ステンレス株式会社 | Ferritic stainless steel plate with excellent heat resistance |
| CN105220074A (en) * | 2015-10-22 | 2016-01-06 | 山西太钢不锈钢股份有限公司 | Chrome ferritic high temperature steel making method in a kind of boiler swing pipe tray use |
-
2018
- 2018-11-30 CN CN201811452857.1A patent/CN109355571B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN109355571A (en) | 2019-02-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105562963B (en) | Lumber recovery it is higher prepare nickel-base alloy bare welding filler metal method | |
| CN109355572B (en) | High-chromium ferrite heat-resistant steel and preparation method thereof | |
| CN105479040B (en) | A kind of preparation method of the higher nickel-base alloy bare welding filler metal of lumber recovery | |
| CN104438418A (en) | Rolling method of stainless steel mold cast steel ingot by one-heating forming | |
| CN102517522A (en) | Steel for hydraulic piece and manufacturing method for steel | |
| CN103962747B (en) | A kind of diameter is less than the nickel-base alloy bare welding filler metal of 3mm | |
| CN108220823B (en) | High temperature resistant stainless steel | |
| CN103882313A (en) | Wire rod for ultrahigh-strength fine cutting steel wire and production method thereof | |
| CN104946932A (en) | Method for manufacturing austenite series heat-resistant alloy pipe and austenite series heat-resistant alloy pipe manufactured by the method | |
| CN103949806A (en) | Preparing method of welding wire | |
| CN103962755B (en) | A kind of diameter is less than the preparation method of 3mm nickel-base alloy bare welding filler metal | |
| CN109355571B (en) | Ferrite heat-resistant stainless steel and preparation method thereof | |
| CN101724783B (en) | Heat resisting type alloy structure steel plate and method for producing same | |
| CN107254639B (en) | A kind of control method of the effective steel of ultra supercritical high-pressure boiler and its continuous casting billet centre burst | |
| CN105506501B (en) | A kind of long-life heat-resistant high alloy steel and its manufacturing method | |
| CN103938111A (en) | Method for reducing non-metallic inclusions in iron-chromium-aluminum electrothermal alloy | |
| CN102618804A (en) | Austenitic heat-resistant steel and production method thereof | |
| CN108779518B (en) | Heat-resistant corrosion-resistant Ni-base alloy having excellent hot forgeability and high Cr content | |
| CN106367689B (en) | A kind of effective steel of high-pressure boiler and preparation method thereof | |
| CN106256921A (en) | A kind of high strength rare earth ytterbium heat resisting steel and manufacture method thereof | |
| CN103949800A (en) | Welding wire made of Cr28 Ni48 W5 nickel base alloy | |
| CN107502833A (en) | A kind of mining machinery swivel pin steel and preparation method thereof | |
| CN109694993B (en) | Super-thick steel plate for high-pressure heater and manufacturing method thereof | |
| CN104611636A (en) | High-temperature-resistant, corrosion-resistant and high-strength steel and manufacturing process thereof | |
| CN103962756A (en) | Method for manufacturing Cr28Ni48W5 nickel base alloy into welding wire |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |