EP1974063A1 - Method for manufacturing ferritic stainless steel slabs with equiaxed grain structures and the ferritic stainless steel manufactured by it - Google Patents
Method for manufacturing ferritic stainless steel slabs with equiaxed grain structures and the ferritic stainless steel manufactured by itInfo
- Publication number
- EP1974063A1 EP1974063A1 EP06812508A EP06812508A EP1974063A1 EP 1974063 A1 EP1974063 A1 EP 1974063A1 EP 06812508 A EP06812508 A EP 06812508A EP 06812508 A EP06812508 A EP 06812508A EP 1974063 A1 EP1974063 A1 EP 1974063A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- molten steel
- ferritic stainless
- concentration
- stainless steel
- grain structures
- 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.)
- Withdrawn
Links
- 238000000034 method Methods 0.000 title claims abstract description 49
- 229910001220 stainless steel Inorganic materials 0.000 title claims abstract description 42
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 35
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 93
- 239000010959 steel Substances 0.000 claims abstract description 93
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 38
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 38
- 239000001301 oxygen Substances 0.000 claims abstract description 38
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims abstract description 36
- 238000005261 decarburization Methods 0.000 claims abstract description 25
- 239000013078 crystal Substances 0.000 claims abstract description 18
- 239000002131 composite material Substances 0.000 claims abstract description 12
- 238000005275 alloying Methods 0.000 claims abstract description 11
- 238000005266 casting Methods 0.000 claims abstract description 9
- 238000007664 blowing Methods 0.000 claims abstract description 7
- 239000002184 metal Substances 0.000 claims abstract description 7
- 229910052751 metal Inorganic materials 0.000 claims abstract description 7
- 239000011261 inert gas Substances 0.000 claims abstract description 6
- 238000003756 stirring Methods 0.000 claims abstract description 6
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 claims description 36
- 235000012255 calcium oxide Nutrition 0.000 claims description 18
- 239000000292 calcium oxide Substances 0.000 claims description 18
- 238000009749 continuous casting Methods 0.000 claims description 10
- 239000002893 slag Substances 0.000 claims description 10
- 239000000203 mixture Substances 0.000 claims description 9
- 238000007670 refining Methods 0.000 claims description 8
- 229910010413 TiO 2 Inorganic materials 0.000 claims description 2
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 abstract description 25
- 230000000694 effects Effects 0.000 abstract description 9
- 229910000859 α-Fe Inorganic materials 0.000 abstract description 9
- QDOXWKRWXJOMAK-UHFFFAOYSA-N dichromium trioxide Chemical compound O=[Cr]O[Cr]=O QDOXWKRWXJOMAK-UHFFFAOYSA-N 0.000 abstract description 8
- 230000007547 defect Effects 0.000 description 8
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 4
- 229910020068 MgAl Inorganic materials 0.000 description 4
- 230000003247 decreasing effect Effects 0.000 description 3
- 238000002347 injection Methods 0.000 description 3
- 239000007924 injection Substances 0.000 description 3
- 238000009628 steelmaking Methods 0.000 description 3
- 229910001021 Ferroalloy Inorganic materials 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- -1 TiN nitride Chemical class 0.000 description 2
- 229910003087 TiOx Inorganic materials 0.000 description 2
- BYFGZMCJNACEKR-UHFFFAOYSA-N aluminium(i) oxide Chemical compound [Al]O[Al] BYFGZMCJNACEKR-UHFFFAOYSA-N 0.000 description 2
- 229910052593 corundum Inorganic materials 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 239000012467 final product Substances 0.000 description 2
- 229910052596 spinel Inorganic materials 0.000 description 2
- 239000011029 spinel Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 description 2
- 229910001887 tin oxide Inorganic materials 0.000 description 2
- HLLICFJUWSZHRJ-UHFFFAOYSA-N tioxidazole Chemical compound CCCOC1=CC=C2N=C(NC(=O)OC)SC2=C1 HLLICFJUWSZHRJ-UHFFFAOYSA-N 0.000 description 2
- 229910001845 yogo sapphire Inorganic materials 0.000 description 2
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- 229910000640 Fe alloy Inorganic materials 0.000 description 1
- 125000004429 atom Chemical group 0.000 description 1
- 238000005097 cold rolling Methods 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 229910001882 dioxygen Inorganic materials 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 125000004433 nitrogen atom Chemical group N* 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
Classifications
-
- 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
- C21C7/068—Decarburising
- C21C7/0685—Decarburising of stainless steel
-
- 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
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/52—Manufacture of steel in electric furnaces
-
- 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
-
- 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
- C21C7/0006—Adding metallic additives
-
- 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
-
- 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
- C21C7/06—Deoxidising, e.g. killing
-
- 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
- C21C7/10—Handling in a vacuum
Definitions
- the present invention relates to a method for manufacturing ferritic stainless steel slabs with equiaxed grain structures and the ferritic stainless steel manufactured by it, and more specifically to a method for manufacturing ferritic stainless steel slabs with equiaxed grain structures and the ferritic stainless steel manufactured by it which control concentration of alumina inclusions in molten steel to maximize an available TiN generation effect serving as a non-uniform nucleating site of ferrite when solidifying it, thereby improving equiaxed crystal ratio.
- TiN is formed by the following equation from a steel making process to a continuous casting process, wherein when its size and distribution are proper, it serves as a non-uniform nucleating site of ferrite in solidifying molten steel, thereby obtaining equiaxed grain structures.
- European Patent No. 924313 has described that equiaxed crystal ratio in slab of 50% or more can be assured when satisfying [%Ti]x%N] ⁇ 0.14x [%A1] among the concentrations of Ti, Al and N.
- European Patent No. 1491646 has described that slabs with equiaxed grain structures can be manufactured by adding Mg of 2 ⁇ 50ppm to the molten steel consisting of Cr:10 ⁇ 20%, C:0.001 ⁇ 0.01%, Si:0.01 ⁇ 0.3%, Mn:0.01 ⁇ 0.3%, N:0.001 ⁇ 0.02%, and Ti:0.05 ⁇ 0.3%.
- Japanese Patent No. 2000-1602999 has described that when making vacuum oxygen decarburization refining, equiaxed crystal ratio in slab of 60% or more can be obtained by injecting CaO and Al to make basicity of CaO-Al O -based slag to be the range of 0.7-2.5 and making molten steel stirring for 5 minutes or more, and adding Ti to allow only TiN nitride to have area ratio of 0.01% or more.
- the present invention is proposed to solve the problems in a prior art as described above. It is an object of the present invention to provide a method for manufacturing ferritic stainless steel slabs with equiaxed grain structures and the ferritic stainless steel manufactured by it, which control concentration of the alumina inclusions in molten steel using composite deoxidation of Si/Mn/Al/Ti in vacuum oxygen decarburization refining process to maximize an available TiN generation effect serving as a non-uniform nucleating site of ferrite when solidifying it, thereby manufacturing ferritic stainless steel slab with high equiaxed crystal ratio and excellent formability, that is, low ridging defect.
- a method for manufacturing ferritic stainless steel slabs with equiaxed grain structures and the ferritic stainless steel manufactured by it according to the present invention as described above precisely controls components of molten steel, such as Si and Mn, etc., and concentration of alumina inclusions to effectively generate available TiN so that it can manufacture ferritic stainless steel slabs with equiaxed grain structures and high equiaxed crystal ratio while improving operating stability, thereby obtaining ferritic stainless steel slabs with equiaxed grain structures having excellent formability, that is, low ridging defect.
- FlG. 1 is a flow chart illustrating a method for manufacturing ferritic stainless steel slabs with equiaxed grain structures according to a preferred embodiment of the present invention
- FlG. 2 is a graph illustrating a change in equiaxed crystal ratio in slabs according to the control of alumina inclusion concentration
- FlG. 3 is a graph illustrating the result of FlG. 2 as distributed data
- FlG. 4 is a graph illustrating the decrease of Al O and TiOx inclusions by a method for manufacturing ferritic stainless steel slabs with equiaxed grain structures according to a preferred embodiment of the present invention, compared to the conventional example;
- FlG. 5 is an electronmicroscope photograph illustrating the form of oxide-TiN composite inclusions distributed inside slabs with equiaxed grain structures by a method for manufacturing ferritic stainless steel slabs with equiaxed grain structures according to a preferred embodiment of the present invention, compared to the conventional example.
- a method for manufacturing ferritic stainless steel slabs with equiaxed grain structures comprising the steps of: performing oxygen decarburization reaction by blowing oxygen from the upper part of the molten steel in a vacuum oxygen decarburization ladle; injecting Al in the molten steel to which the oxygen decarburization reaction is made for Cr O reduction; making composite deoxidation by injecting deoxidizer in the molten steel into which the Al is injected for the Cr O reduction; making alloying process by injecting alloying metal in the molten steel; first judging for judging whether Al concentration is in the range of a setting value by analyzing the Al concentration in the molten steel; if the Al concentration satisfies the setting value, stirring it using inert gas and second judging for judging whether alumina inclusion concentration in the final molten steel corresponds to a target value; and if the alumina inclusion concentration satisfies the target value, continuously casting the molten steel.
- the deoxidizer in the composite deoxidating step, may be Si and Mn and in the allyoing step, the alloying metal may be Ti with 0.2-0.4 % by mass.
- the alumina inclusion concentration in the molten steel satisfies the following condition.
- the final composition of a refined slag in the vacuum oxygen decarburization refining ladle satisfies the following condition. [45] 1. l ⁇ (%CaO)/(% Al 2 O ) ⁇ 1.4
- the molten steel is 80-85 ton.
- the setting value of Al concentration in the first judging step is
- the Al concentration is less than 0.05 % by mass, it further comprises the step of additionally injecting Al of 30 ⁇ 40kg relative to the molten steel of 80-85 ton and if the Al concentration is 0.12 % by mass or more, it further comprises the step of additionally injecting quicklime of 250 ⁇ 300kg relative to the molten steel of 80-85 ton.
- the target value of the alumina inclusion concentration in the second judging is 70 ppm or less.
- the ferritic stainless steel slabs with equiaxed grain structure of the present invention are manufactured according to a method for manufacturing ferritic stainless steel slabs with equiaxed grain structures of the present invention, wherein it is characterized in that the alumina inclusion concentration is 70 ppm or less and equiaxed crystal ratio in slabs is 40% or more.
- FIG. 1 a flow chart illustrating a method for manufacturing ferritic stainless steel slabs with equiaxed grain structures according to a preferred embodiment of the present invention.
- a method for manufacturing ferritic stainless steel slabs with equiaxed grain structures comprises the steps of: performing (SlO) oxygen decarburization reaction by blowing oxygen from the upper part of the molten steel in a vacuum oxygen decarburization ladle; injecting Al in the molten steel to which the oxygen decarburization reaction is made for Cr O reduction (S20); making composite deoxidating (S30) by injecting deoxidizer in the molten steel into which the Al is injected for the Cr O reduction; making alloying process (S40) by injecting alloying metal in the molten steel; first judging (S50) for judging whether Al concentration is in the range of a setting value by analyzing the Al concentration in the molten steel; if the Al concentration satisfies the setting value, stirring (S60) it using inert gas and second judging (S70) for judging whether the alumina inclusion concentration in the final molten steel corresponds to a target value; and if
- the deoxidizer is Si and Mn and in the allyoing step (S40), the alloying metal is Ti.
- FlG. 2 is a graph illustrating a change in equiaxed crystal ratio in slabs according to the control of the alumina inclusion concentration and FlG. 3 is a graph illustrating the result of FlG. 2 as distributed data.
- the equiaxed crystal ration in slabs is increased as the alumina inclusion concentration in the molten steel is decreased.
- a proper concentration of the alumina inclusions can be set to be less than 70ppm.
- the slabs with equiaxed crystal ratio of 40-100% can be obtained.
- the alumina inclusion concentration exceeds 70ppm, the creation of available TiN is suppressed so that it is impossible to assure a targeted equiaxed crystal ratio.
- the step of decreasing Cr O by injecting Al controls a targeted composition by making composite deoxidation by injecting Si and Mn and then injecting Ti.
- the Al concentration is primarily analyzed. If the primary Al concentration is too low, Al is further injected and if too high, quicklime is further injected. Subsequently, they are stirred using inert gas in the bottom of the ladle so that the alumina inclusion concentration in the final molten steel is controlled to conform to the targeted range to make a continuous casting.
- the present invention can obtain higher equiaxed crystal ratio of 40% or more, compared with the example of the prior art.
- TiN is formed in the molten steel by the reaction of the equation 1 ; however, a point in time forming it varies depending on the composition and temperature of the molten steel. If TiN is formed in the ladle or a tundish prior to solidifying the molten steel, TiN may be generated through a uniform nucleating and growing by the reaction of Ti atom with N atom, however, it is advantageous that the nucleating is made at the third interface in terms of thermodynamics, for example, at the interface of oxidation-inclusions/molten steel, etc.
- ⁇ A1203-TiN between Al 2 O 3 of a hexagonal structure and TiN of a fa centered cubic (FCC) structure is approximately 0.1, whereas ⁇ betw ⁇
- MgO or MgAl O spinel of the same face-centered cubic and the TiN is approxin 0.0002.
- the MgO-based inclusions will easily serves as the non-uniform nucleating site, rather than the Al O -based inclusions.
- the TiN nucleating is degraded so that upon solidifying, it may be a factor to cause the non-uniform nucleating of ferrite to degrade.
- TiO -based inclusions it is necessary to obtain a composite deoxidation effect by injecting Si/Mn.
- FlG. 4 is a graph illustrating the decrease of Al O and TiOx inclusions by a method for manufacturing ferritic stainless steel slabs with equiaxed grain structures according to a preferred embodiment of the present invention, compared to the conventional example.
- the [Al] concentration is primarily analyzed in the molten steel at a point in time elapsing about 5 minutes after the injection.
- the Al concentration is less than 0.05%
- the amount of Al added is 30-40 kg.
- the amount of quicklime added is 250-300 kg.
- the final composition of refined slag in the vacuum oxygen decarburization ladle is l.l ⁇ (%CaO)/(%Al O ) ⁇ 1.4 and 4 ⁇ (%TiO )/(% SiO ) ⁇ 6.
- the ladle is moved to the vacuum oxygen decarburization refining stand in which a vacuum cover is put on it and oxygen gas is then supplied to it using a lance on the upper part of the molten steel.
- the temperature of the molten steel is raised up to about 1670°C and the composition of the molten steel is analyzed as in the following table 2.
- the ladle is transferred to a continuous casting process.
- the component of the molten steel in the final tundish is analyzed as in the following table 3.
- N concentration in the molten steel is about 110 ppm and reacts with 0.30% [Ti] to contribute the generation of available TiN as shown in FlG. 5, thereby obtain slabs with equiaxed grain structures.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Continuous Casting (AREA)
Abstract
Description
Claims
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020050131297A KR100729934B1 (en) | 2005-12-28 | 2005-12-28 | Method for manufacturing ferritic stainless steel slabs with equiaxed grain structures and the ferritic stainless steel manufactured by it |
PCT/KR2006/004673 WO2007074970A1 (en) | 2005-12-28 | 2006-11-09 | Method for manufacturing ferritic stainless steel slabs with equiaxed grain structures and the ferritic stainless steel manufactured by it |
Publications (2)
Publication Number | Publication Date |
---|---|
EP1974063A1 true EP1974063A1 (en) | 2008-10-01 |
EP1974063A4 EP1974063A4 (en) | 2010-07-21 |
Family
ID=38218177
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP06812508A Withdrawn EP1974063A4 (en) | 2005-12-28 | 2006-11-09 | Method for manufacturing ferritic stainless steel slabs with equiaxed grain structures and the ferritic stainless steel manufactured by it |
Country Status (6)
Country | Link |
---|---|
US (1) | US20090223603A1 (en) |
EP (1) | EP1974063A4 (en) |
JP (1) | JP5221379B2 (en) |
KR (1) | KR100729934B1 (en) |
CN (1) | CN101351565B (en) |
WO (1) | WO2007074970A1 (en) |
Families Citing this family (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2047926A1 (en) * | 2007-10-10 | 2009-04-15 | Ugine & Alz France | Method of manufacturing stainless steels comprising fine carbonitrides, and product obtained from this method |
KR100922059B1 (en) * | 2007-12-20 | 2009-10-16 | 주식회사 포스코 | Method for manufacturing high chrome stainless steel including titannium |
CN102199688B (en) * | 2010-03-25 | 2013-02-06 | 宝山钢铁股份有限公司 | Method for efficiently refining ultra-pure ferritic stainless steel |
TWI412597B (en) * | 2010-05-28 | 2013-10-21 | China Steel Corp | Bearing steel refining method for improving fatigue life |
JP6247004B2 (en) | 2010-11-05 | 2017-12-13 | 国立大学法人九州大学 | Preventive or therapeutic agent for acute pain associated with herpes zoster |
KR101198589B1 (en) | 2010-12-27 | 2012-11-06 | 주식회사 포스코 | Method of refining of high Cr ferrite stainless steel and refining apparatus thereby |
JP5687590B2 (en) * | 2011-09-27 | 2015-03-18 | 日本冶金工業株式会社 | Method for producing boron-containing stainless steel |
JP6306353B2 (en) * | 2014-01-21 | 2018-04-04 | Jfeスチール株式会社 | Method for producing slab for ferritic stainless steel cold rolled steel sheet and method for producing ferritic stainless steel cold rolled steel sheet |
HUE052879T2 (en) * | 2015-04-17 | 2021-05-28 | Univ Missouri | Grain refinement in iron-based materials |
KR101898165B1 (en) * | 2016-12-06 | 2018-09-13 | 주식회사 포스코 | Method for manufacturing ferritic stainless steel having fine cast structure |
KR101896340B1 (en) * | 2017-06-01 | 2018-09-07 | 주식회사 포스코 | Molten steel manufacturing method |
CN107574385B (en) * | 2017-08-28 | 2019-07-12 | 北京科技大学 | A kind of process improving bistable ferrite stainless steel continuous casting billet equiaxial crystal ratio |
CN113502376A (en) * | 2021-06-18 | 2021-10-15 | 鞍钢联众(广州)不锈钢有限公司 | Method for improving secondary skin inclusion of titanium-containing stainless steel billet |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0924313A1 (en) * | 1997-12-19 | 1999-06-23 | Armco Inc. | Non-ridging ferritic chromium alloyed steel |
JP2000073146A (en) * | 1998-08-27 | 2000-03-07 | Nisshin Steel Co Ltd | Ferritic stainless steel excellent in ridging resistance |
JP2000160230A (en) * | 1998-11-20 | 2000-06-13 | Nisshin Steel Co Ltd | Production of ferritic stainless steel excellent in ridging resistance |
EP1099498A1 (en) * | 1999-04-08 | 2001-05-16 | Nippon Steel Corporation | Cast steel piece and steel product excellent in forming characteristics and method for treatment of molted steel therefor and method for production thereof |
JP2004143510A (en) * | 2002-10-23 | 2004-05-20 | Nippon Steel Corp | Method for melting steel sheet for extra low carbon or low carbon thin sheet having excellent surface quality, and continuously cast slab |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0949010A (en) * | 1995-08-09 | 1997-02-18 | Nisshin Steel Co Ltd | Production of continuous casting ferritic stainless steel slab having high equi-axial crystal ratio |
JP3288626B2 (en) * | 1997-03-21 | 2002-06-04 | 新日本製鐵株式会社 | High workability ferritic stainless steel sheet excellent in ridging characteristics and method for producing the same |
JP2001049322A (en) * | 1999-08-05 | 2001-02-20 | Nisshin Steel Co Ltd | Production of ferritic stainless steel excellent in ridging resistance |
JP3668087B2 (en) * | 2000-02-03 | 2005-07-06 | 日本冶金工業株式会社 | High-cleaning refining method for stainless steel |
KR100355369B1 (en) * | 2000-06-07 | 2002-10-11 | 고려용접봉 주식회사 | Flux cored wire for arc-welding of austenitic stainless steel |
JP3624804B2 (en) * | 2000-07-14 | 2005-03-02 | 住友金属工業株式会社 | Method for producing ridging resistant ferritic stainless steel |
DE602005021286D1 (en) * | 2004-09-15 | 2010-07-01 | Sumitomo Metal Ind | Steel pipe with excellent resistance to flaking on the inner surface |
-
2005
- 2005-12-28 KR KR1020050131297A patent/KR100729934B1/en active IP Right Grant
-
2006
- 2006-11-09 JP JP2008548373A patent/JP5221379B2/en not_active Expired - Fee Related
- 2006-11-09 EP EP06812508A patent/EP1974063A4/en not_active Withdrawn
- 2006-11-09 US US12/158,515 patent/US20090223603A1/en not_active Abandoned
- 2006-11-09 CN CN2006800497022A patent/CN101351565B/en not_active Expired - Fee Related
- 2006-11-09 WO PCT/KR2006/004673 patent/WO2007074970A1/en active Application Filing
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0924313A1 (en) * | 1997-12-19 | 1999-06-23 | Armco Inc. | Non-ridging ferritic chromium alloyed steel |
JP2000073146A (en) * | 1998-08-27 | 2000-03-07 | Nisshin Steel Co Ltd | Ferritic stainless steel excellent in ridging resistance |
JP2000160230A (en) * | 1998-11-20 | 2000-06-13 | Nisshin Steel Co Ltd | Production of ferritic stainless steel excellent in ridging resistance |
EP1099498A1 (en) * | 1999-04-08 | 2001-05-16 | Nippon Steel Corporation | Cast steel piece and steel product excellent in forming characteristics and method for treatment of molted steel therefor and method for production thereof |
JP2004143510A (en) * | 2002-10-23 | 2004-05-20 | Nippon Steel Corp | Method for melting steel sheet for extra low carbon or low carbon thin sheet having excellent surface quality, and continuously cast slab |
Non-Patent Citations (1)
Title |
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See also references of WO2007074970A1 * |
Also Published As
Publication number | Publication date |
---|---|
JP2009521599A (en) | 2009-06-04 |
WO2007074970A1 (en) | 2007-07-05 |
KR100729934B1 (en) | 2007-06-18 |
US20090223603A1 (en) | 2009-09-10 |
CN101351565A (en) | 2009-01-21 |
JP5221379B2 (en) | 2013-06-26 |
CN101351565B (en) | 2011-02-02 |
EP1974063A4 (en) | 2010-07-21 |
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