WO2001027342A1 - Steel for welded structure purpose exhibiting no dependence of haz toughness on heat input and method for producing the same - Google Patents
Steel for welded structure purpose exhibiting no dependence of haz toughness on heat input and method for producing the same Download PDFInfo
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- WO2001027342A1 WO2001027342A1 PCT/JP2000/007091 JP0007091W WO0127342A1 WO 2001027342 A1 WO2001027342 A1 WO 2001027342A1 JP 0007091 W JP0007091 W JP 0007091W WO 0127342 A1 WO0127342 A1 WO 0127342A1
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- Prior art keywords
- steel
- heat input
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- haz toughness
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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
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- 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
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/064—Dephosphorising; Desulfurising
-
- 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
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
-
- 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
- C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
Definitions
- the present invention relates to steel for welded structures used in marine structures, line pipes for transporting natural gas and crude oil, construction, shipbuilding, bridges, construction machines, and the like, and a method for producing the same. More specifically, in the present invention, the toughness of the welded part is required, and even when welding is performed under a wide range of heat input conditions, the heat input during welding is from 0.5 kJ Zmm to more than 150 kJ Zmm.
- the former austenite grain size in the heat affected zone hereinafter referred to as “HAZ”) is small, and the toughness of the weld heat affected zone (hereinafter referred to as “HAZ toughness”) is excellent regardless of the heat input conditions. It relates to steel for welded structures. Background art
- Japanese Unexamined Patent Publication (Kokai) No. 59-190313 discloses a welding method characterized by deoxidizing molten steel with Ti or a Ti alloy and then adding Al, Mg and the like.
- a method for producing a steel material having excellent properties is disclosed. This production method uses the effect of increasing the ferrite fraction by using Ti oxide as a transformation nucleus of ferrite, and conventionally utilizes the pinning effect of precipitates such as nitrides. This is a technique to improve the HAZ toughness by a method different from the method of performing HAZ.
- the gist of these inventions is that “ferrite nucleation at the time of ⁇ ⁇ hypertransformation, that is, And uniformly disperse the Ti-containing oxides that can be used for the miniaturization of the oxides.This does not ensure the pinning effect due to nitrides and the like as described above, but occurs during the cooling process. By promoting the fly transformation during the ⁇ ⁇ ⁇ transformation, the formation of a coarse embrittlement structure is suppressed, and the structure is refined.
- the method for introducing oxides is to remove Ti and other substances in the steel smelting process.
- oxide agglomerates form during the retention of molten steel, leading to the formation of coarse oxides, which in turn impairs copper cleanliness and reduces toughness.
- various devices such as a complex deoxidation method have been devised in order to reduce the size of these oxides.
- the present invention improves the conventional composite deoxidation method, disperses oxides and / or nitrides more finely and more uniformly than before, and furthermore, the finely dispersed particles also have ferrite transformation ability. It is an object of the present invention to provide a steel for a welded structure having excellent HAZ toughness in welding under any heat input conditions including super-high heat input.
- the gist of the present invention is as follows.
- O contains 0.001 to 0.08%, with the balance being iron and unavoidable impurities, Particles precipitated from Mg-containing oxides with a particle diameter of 0.2 to 5 ⁇ as nuclei, either sulfides or nitrides alone or in combination of both, are average particles. Dispersed in steel at an interval of 30 to 100 ⁇ , or with Mg-containing oxides with particle diameters of less than 0.05 to 0. Or the particles precipitated by combining both are dispersed in the steel with an average particle interval of 30 ⁇ m or less.
- R EM One or more of 0.005 to 0.005% of HAZ toughness described in (1) or (2) above is contained. Steel for welded structures without heat dependence.
- the former austenite grain size of the HAZ structure is not affected by welding heat input.
- T i 0.003 to 0.05 mass 0 and the required amount of Mg .
- Figure 1 is a diagram showing the former ⁇ grain size in HAZ when the welding heat input was changed.
- FIG. 2 is a diagram schematically showing a morphology of a composite particle having an ultrafine Mg oxide as a nucleus.
- Mg has conventionally been known as a strong deoxidizing agent and desulfurizing agent, as an element that increases the cleanliness of steel and improves HAZ toughness.
- Japanese Patent Application Laid-Open No. 59-19013 discloses a technique of composite addition in which Mg is added after Ti is added.
- the purpose of the technique is to promote the increase of Ti oxides, which are intragranular transformation nuclei, by the addition of Mg. It does not achieve fine graining by finely dispersing and pinning.
- the present inventors have focused on the action of Mg as a strong deoxidizing agent, and have taken advantage of the property that coagulation and coarsening are less likely to occur than A 1, and that Ti-added copper is used. Then, the idea was reached that if the order and amount of the deoxidizing agent added in the steelmaking process were controlled, there would be room for the fine dispersion of oxides.
- the present invention will be described in detail.
- the present inventors systematically investigated the state of oxides when Mg was added to molten steel that had been weakly deoxidized with Ti added.
- one is a Mg-containing oxide having a particle diameter of 0.2 to 5.0 m, and the other is an ultrafine MgO or M having a particle diameter of 0.005 to 0. ⁇ . It is a g-containing oxide.
- the generation of such oxides is presumed to be based on the following reasons.
- the addition amount of Mg is limited to about 30 to 50 ppm.
- Mg can be added up to 100 ppm.
- the oxides generated in the steel become nucleation sites for sulfides and nitrides during fabrication or during the subsequent cooling process or reheating-hot process.
- the state of oxides in steel was as follows.
- Mg-containing oxides with a particle size of 0.2 to 5 ⁇ , and either sulfides or nitrides, or a mixture of both, is averaged. It is contained in steel with a particle interval of 30 to 100 / zm.
- Mg-containing oxide having a particle size of 0.05 to less than 0.2 / zm as nuclei, one of sulfide and nitride alone, or a combination of both These particles are contained in the steel with an average particle interval of 30 ⁇ or less.
- the present invention relates to a steel material having excellent HAZ toughness achieved by the presence of the oxides of 1) and Z or 2) above. This is to provide a revolutionary technology that can minimize the change in toughness in steel.
- the intragranular transformation is promoted when the number of oxides is large and when sulfides and nitrides are deposited on the oxide. As shown in 1) above, the number increased by more than 10 times compared to the conventional ones.Also, with regard to complex precipitation, 100% sulfide or nitride Since the compound is precipitated in a complex manner, the Mg-containing oxide of the present invention has an extremely large intragranular transformation ability.
- FIG. Figure 1 shows the old ⁇ particle size in HAZ with 0.10 C—1.
- OM n steel as the base component and the heat input on the horizontal axis, for each heat input condition [1 kJ Zmm, 1 0 kJZmm, 50 kJZmm, 100 kjZmm, 150 kJ / mm].
- the old ⁇ particle size in the case of a real joint, after a part of ⁇ was extracted by cutting or the like, it was polished, and furthermore, the microstructure obtained by nital corrosion was obtained. Tissues were photographed with an optical microscope at a magnification of 50 to 200 times (5 or more) and cut by a cutting method.
- the old y grain size of 1 to 50 kJ / mm in Fig. 1 is the value obtained by this method.
- grain boundary ferrite is generated along the old ⁇ grain boundary, so that the force calculated as the old ⁇ grain including the grain boundary ferrite, or It is usual to measure the old ⁇ particle size from the microstructure obtained by heating to the specified conditions using a reproducible thermal cycle tester with the same heat equivalent and then quenching.
- the former ⁇ particle size for 100 kJ Zmm and 150 kJ mm is a value obtained from the microstructure formed using the latter reproducible thermal cycle tester.
- the presence state of the oxide described in 2) above depends on the refinement of the former ⁇ grain size. Is a dominant factor.
- the Mg ultrafine oxide acts as a preferential precipitation site for sulfides and nitrides. That is, it is considered that the presence of a large number of the preferential precipitation sites increases the number of nitrides effective for pinning crystal grains.
- one of the features of the present invention is that, unlike the conventional steel, in which crystal grains are pinned by using a nitride such as Ti, in addition to the marked improvement of the intragranular transformation ability.
- a nitride such as Ti
- oxides such as MgO into the steel finely, the precipitation nuclei of the nitride are created, thereby increasing the number of the nitrides, thereby reducing the nitrides.
- the existence of these composite particles makes it possible to obtain old ⁇ grains of 100 to 200 m or less with HAZ.
- Another feature of the present invention is that, even in adult heat to ultra-high heat input welding, in which nitride has been dissolved and no improvement effect of toughness has been obtained conventionally, grain growth is suppressed by oxide alone. Due to this effect, the former ⁇ particle size hardly changes in HAZ.
- the optimum amount of Mg added depends on the amount of oxygen present in the molten steel after the addition of Ti, but according to experiments, the oxygen concentration at that time depends on the amount of Ti added and the time until the addition of Mg. Therefore, after all, the amount of Ti and the amount of Mg added may be controlled within an appropriate range.
- the appropriate amount of dissolved oxygen at the final Mg addition is about 0.1 to 50 ppm.
- the minimum 0.1 ppm is the minimum amount of dissolved oxygen that can produce fine Mg oxides.
- the limit was set at 50 ppm.
- C is a basic element that improves the strength of the base metal of steel. In order to ensure the improvement effect, it is necessary to add 0.1% or more.However, an excessive addition exceeding 0.2% causes a decrease in the weldability and toughness of the steel material. . 2%.
- S i is an element necessary as a deoxidizing element in steelmaking, and the addition of more than 0.02% to steel requires a force exceeding 0.5%, which lowers the HAZ toughness. , 0.5% as the upper limit.
- Mn is an element necessary for ensuring the strength and toughness of the base metal.However, if added over 2%, it significantly impairs the HAZ toughness, and conversely, if added less than 0.3%, Since it is difficult to secure the strength, the range of the added amount is 0.3 to 2%.
- P is an element that affects the toughness of steel. If contained in excess of 0.03%, not only the base metal but also the toughness of HAZ is significantly impaired, so the upper limit is 0.3%.
- S is contained in excess of 0.03%, coarse sulfides are formed and the toughness is impaired.However, if S is less than 0.001%, the content of intragranular ferrite is reduced. Since the amount of sulfide, such as MnS, that is effective for formation is significantly reduced, the addition amount is set to be in the range of 0. Q001 to 0.03%.
- a 1 is usually added as a deoxidizing agent, but in the present invention, If added in excess of 0.05%, the effect of the addition of Mg is impaired, so the upper limit is 0.05%. Also, stable, in order to generate ⁇ 2 0 4 is less and also 0.0 0 0 5% because it is necessary, to 0.0 0 0 5% lower limit.
- T i is an element that exerts an effect on grain refinement as a deoxidizing agent and also as a nitride-forming element, but when added in large amounts, the toughness due to the formation of carbides Therefore, the upper limit must be set to 0.05%. Then, in order to obtain a predetermined effect, 0.003% or more of addition is necessary. Therefore, the range of the addition amount is set to 0.003% to 0.05%.
- Mg is a main alloying element in the present invention, and is mainly added as a deoxidizing agent, but if added in excess of 0.01%, coarse oxides are likely to be generated. As a result, the base material and HAZ toughness decrease. However, if the addition is less than 0.0001%, the intragranular transformation and the formation of oxides required as pinning particles cannot be sufficiently expected. Therefore, the range of the addition amount is set to 0.0001 to 0.010%.
- ⁇ oxygen
- oxygen is an essential element for generating Mg-containing oxides. If the amount of oxygen finally remaining in the steel is less than 0.001%, the number of oxides will not be sufficient, so the lower limit is 0.001%. On the other hand, if the residual amount exceeds 0.008%, the amount of coarse oxides increases, resulting in a decrease in base metal toughness and HAZ toughness. Therefore, the upper limit is made 0.008%.
- elements for improving strength and toughness one of the following elements: Cu, Ni, Cr, Mo, V, Nb, Zr, Ta, and B Alternatively, two or more elements can be added.
- Cu is an element effective for increasing strength without reducing toughness. Force is ineffective at less than 0.05%, and copper flakes are heated at over 1.5%. Cracks during welding and welding. Therefore, the content range is set to 0.05 to: 0.5%.
- Ni is an element effective in improving toughness and strength.To obtain the effect, Ni must be added in an amount of 0.05% or more. Since it decreases, the upper limit is set to 5%.
- Cr is effective for improving the strength of steel by precipitation strengthening.
- the addition of 0.02% or more is effective. When added in a large amount exceeding 1.5%, hardenability is increased and It will give rise to tissue and reduce toughness. Therefore, the upper limit is 1.5%.
- Mo is an element that forms a carbonitride and improves the strength at the same time as improving the hardenability.To obtain the effect, it is necessary to add 0.02% or more. Addition of a large amount exceeding 5%, together with unnecessarily strengthening, causes a marked decrease in toughness. Therefore, the content range is set from 0.02 to: 1.5%.
- V is an element that forms carbides and nitrides and is effective in improving the strength.It has no effect when it is added at less than 0.01%, and conversely, when it exceeds 0.1%.
- the content range is set to 0.0 :! to 0.1%, since it causes a decrease.
- Nb is an element that forms carbides and nitrides and is effective in improving the strength.However, Nb has no effect when added at less than 0.001%, and has toughness when added at more than 0.2%. The content range is set to 0.0001 to 0.2% because it causes a decrease.
- Z r and T a are also carbides like the N b, is an element which is effective in improving the form nitrides strength, 0.0 0 0 no its effect is the addition of less than 1%, 0. If the addition exceeds 0.5%, on the contrary, the toughness is reduced. Therefore, the content range is set to 0.001% to 0.05%.
- B generally increases hardenability when it forms a solid solution. It is an element that reduces solid solution N and improves the toughness of the heat affected zone. Therefore, the effect can be utilized by adding 0.0003% or more. Addition of excessive force causes toughness to decrease, so the upper limit is made 0.005%.
- Ca and REM suppress the generation of elongated MnS, and improve the properties in the thickness direction of the steel material, particularly, the resistance to lamellarity. If both C a and RE M are less than 0.0005%, this effect cannot be obtained, so the lower limit is set to 0.005%. Conversely, if the content exceeds 0.005%, the number of oxides of Ca and REM increases, and the number of ultrafine Mg-containing oxides decreases. 0 5%.
- a steel ingot having the chemical composition shown in Tables 1 and 2 (continued from Table 1) was subjected to hot rolling and heat treatment under the conditions shown in Table 3 to obtain a steel sheet.
- a small heat input of kj Zmm, a large heat input of 20 kj Zmm, and a super large heat input of 150 kJ Zmm were applied.
- the old ⁇ particle size in HAZ is measured by the cutting method described above.
- the heat input dependence of the HAZ toughness (the sample collection position was in the coarsest grain area) was evaluated by the Charpy impact test. Table 3 also shows the results.
- ⁇ in Table 3 is the difference between the Charpy absorbed energy between the small heat input (1.7 kJ Zmm) and the very large heat input (150 kJ Zmm), that is, [small heat input Toughness at the time of: VE 0 (J)]-[Toughness at the time of extra large heat input: VE o (J)] was calculated, and the absorbed energy of each was measured for three test pieces at 0 ° C. It is the average of the values.
- the average particle size of the oxide was calculated from the electron micrograph of L 1 with a magnification of 100 ⁇ and the electron micrograph of ⁇ 2 with a magnification of 100,000. The interval.
- d1 Heat input 1.7kJ / mm old 7 particle size
- d2 Heat input 20. OkJ / old old ⁇ particle size
- d3 Heat input 150.0kJZ old a particle size (However, 20-2 D3 is the heat input 60. OkJZ ⁇ old particle size)
- ⁇ 1 Average particle spacing of the contained oxide (0.2 to 5.0 / ⁇ 111)
- ⁇ 2 Average particle spacing of the contained oxide (0.005 to 0.2 "111)
- the force 1 is steel 2 1 _ 2, but the force is out of the range specified in the present invention; in these cases, even in steel 20 — 2, It was recognized that the particle size was hardly changed, and that the steel 21-2 had a particle size of 200 ⁇ m or less under the heat input condition of 60.0 kJ / mm. I understand.
- the Charpy absorbed energy of these invention steels all exceeded 10 kgf ⁇ m, indicating that the above invention steels are high toughness steels.
- the difference in the Charpy absorption energy in each case is as small as at most about 4 kgf ⁇ ⁇ or less, and there is no significant change in HA toughness even in a wide range of heat input conditions.
- steels 23-35 represent comparative steels produced deviating from the method of the present invention. That is, the comparative steels 23, 24, 25, 26, 27, 29, 30, 33, 34, and 35 are each composed of one of the basic components or selected elements. This is an example in which the compound is added beyond the composition range specified in the invention.
- Comparative steel 28 and comparative steel 31 are steels in which A 1 and T i are smaller than the lower limits of A 1 and T i specified in the present invention, respectively, as the heat input increases.
- the old ⁇ grain size is coarse, and the comparative steel 28 and the comparative steel 31 both have low toughness values.
- the comparative steel 32 has no added Mg, and has good toughness under a small heat input condition, but has a large toughness deterioration under a super-adult heat condition.
- the difference in Charpy absorbed energy is as large as 10.3 kgf ⁇ m.
- the HAZ toughness is at a low level, and when the heat input is large, the HAZ toughness is further reduced.
- Comparative Steel 33 and Comparative Steel 34 the former ⁇ grain size was sufficiently smaller than the others because of the presence of many fine oxides. Nevertheless, the toughness is significantly degraded.
- Comparative Steel 36 and Comparative Steel 37 have the same chemical composition as Inventive Steel 1 and Inventive Steel 2, respectively, but when a predetermined amount of the final Mg is added, the amount of dissolved oxygen in the molten steel was over 50 ppm.
- an appropriate predetermined amount of Mg is added after the addition of Ti, or an appropriate predetermined amount of Mg is added after the simultaneous addition of Ti and Mg. Accordingly, the growth of old ⁇ grains in HAZ can be suppressed regardless of the heat input condition.
- the toughness can be improved over a wide range of heat input conditions due to this suppression effect.
- the present invention greatly contributes to the development of various industrial technologies.
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Abstract
Description
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Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2001529471A JP3802810B2 (en) | 1999-10-12 | 2000-10-12 | Steel for welded structures having no dependence on heat input of HAZ toughness and method for manufacturing |
DE60020522T DE60020522T2 (en) | 1999-10-12 | 2000-10-12 | STEEL FOR WELDED STRUCTURES, IN WHICH TOGGLE IS INDEPENDENT OF THE HEAT ENTRY, AND METHOD OF MANUFACTURING |
EP00966448A EP1143023B1 (en) | 1999-10-12 | 2000-10-12 | Steel for welded structure purpose exhibiting no dependence of haz toughness on heat input and method for producing the same |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP28941299 | 1999-10-12 | ||
JP11/289412 | 1999-10-12 |
Publications (1)
Publication Number | Publication Date |
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WO2001027342A1 true WO2001027342A1 (en) | 2001-04-19 |
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ID=17742916
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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PCT/JP2000/007091 WO2001027342A1 (en) | 1999-10-12 | 2000-10-12 | Steel for welded structure purpose exhibiting no dependence of haz toughness on heat input and method for producing the same |
Country Status (5)
Country | Link |
---|---|
EP (1) | EP1143023B1 (en) |
JP (1) | JP3802810B2 (en) |
KR (1) | KR100430067B1 (en) |
DE (1) | DE60020522T2 (en) |
WO (1) | WO2001027342A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003049237A (en) * | 2001-08-06 | 2003-02-21 | Nippon Steel Corp | High strength steel for welding structure having excellent base metal toughness and haz toughness and production method therefor |
Families Citing this family (11)
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KR100605717B1 (en) * | 2001-12-27 | 2006-08-01 | 주식회사 포스코 | Steels for Welded Structures With Finely Disperded Oxides of Ti-Al-Zr-Mg |
CN100402688C (en) * | 2002-09-04 | 2008-07-16 | 杰富意钢铁株式会社 | Steel material for high heat input welding and its manufacturing method |
WO2004106571A1 (en) * | 2003-05-27 | 2004-12-09 | Nippon Steel Corporation | High strength thin steel sheet excellent in resistance to delayed fracture after forming and method for preparation thereof, and automobile parts requiring strength manufactured from high strength thin steel sheet |
CA2542762C (en) | 2003-10-17 | 2012-11-13 | Nippon Steel Corporation | High-strength steel sheets excellent in hole-expandability and ductility |
DE102007004147A1 (en) * | 2007-01-22 | 2008-07-24 | Heraeus Electro-Nite International N.V. | Method for influencing the properties of cast iron and oxygen sensor |
CN101578384B (en) | 2007-12-07 | 2011-06-15 | 新日本制铁株式会社 | Steel with weld heat-affected zone having excellent CTOD properties and process for producing the steel |
JP4547044B2 (en) * | 2008-07-30 | 2010-09-22 | 新日本製鐵株式会社 | High-strength thick steel material excellent in toughness and weldability, high-strength extra-thick H-shaped steel, and methods for producing them |
EP2385149B1 (en) * | 2009-05-19 | 2016-07-06 | Nippon Steel & Sumitomo Metal Corporation | Steel material for welding and method for producing same |
TWI365915B (en) | 2009-05-21 | 2012-06-11 | Nippon Steel Corp | Steel for welded structure and producing method thereof |
US9403242B2 (en) | 2011-03-24 | 2016-08-02 | Nippon Steel & Sumitomo Metal Corporation | Steel for welding |
KR101883588B1 (en) * | 2014-04-15 | 2018-07-30 | 신닛테츠스미킨 카부시키카이샤 | Steel h-beam and method for manufacturing same |
Citations (5)
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JPH0543977A (en) * | 1991-08-14 | 1993-02-23 | Nippon Steel Corp | Production of low temperature high toughness steel for welding |
JPH09310147A (en) * | 1996-05-21 | 1997-12-02 | Nippon Steel Corp | Steel sheet excellent in heat affected zone toughness |
JPH10298705A (en) * | 1997-02-19 | 1998-11-10 | Nippon Steel Corp | Steel for super heat input welding containing mg |
JPH1121613A (en) * | 1997-05-07 | 1999-01-26 | Nippon Steel Corp | Production of steel excellent in toughness at low temperature and sour resistance |
JPH11293382A (en) * | 1998-04-15 | 1999-10-26 | Nippon Steel Corp | Magnesium-containing steel for extra-large heat input welding |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH03177535A (en) * | 1989-12-04 | 1991-08-01 | Nippon Steel Corp | Manufacture of low temperature high toughness steel for welding |
-
2000
- 2000-10-12 KR KR10-2001-7007269A patent/KR100430067B1/en active IP Right Grant
- 2000-10-12 WO PCT/JP2000/007091 patent/WO2001027342A1/en active IP Right Grant
- 2000-10-12 DE DE60020522T patent/DE60020522T2/en not_active Expired - Lifetime
- 2000-10-12 EP EP00966448A patent/EP1143023B1/en not_active Expired - Lifetime
- 2000-10-12 JP JP2001529471A patent/JP3802810B2/en not_active Expired - Fee Related
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0543977A (en) * | 1991-08-14 | 1993-02-23 | Nippon Steel Corp | Production of low temperature high toughness steel for welding |
JPH09310147A (en) * | 1996-05-21 | 1997-12-02 | Nippon Steel Corp | Steel sheet excellent in heat affected zone toughness |
JPH10298705A (en) * | 1997-02-19 | 1998-11-10 | Nippon Steel Corp | Steel for super heat input welding containing mg |
JPH1121613A (en) * | 1997-05-07 | 1999-01-26 | Nippon Steel Corp | Production of steel excellent in toughness at low temperature and sour resistance |
JPH11293382A (en) * | 1998-04-15 | 1999-10-26 | Nippon Steel Corp | Magnesium-containing steel for extra-large heat input welding |
Non-Patent Citations (1)
Title |
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See also references of EP1143023A4 * |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003049237A (en) * | 2001-08-06 | 2003-02-21 | Nippon Steel Corp | High strength steel for welding structure having excellent base metal toughness and haz toughness and production method therefor |
Also Published As
Publication number | Publication date |
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DE60020522D1 (en) | 2005-07-07 |
KR100430067B1 (en) | 2004-05-03 |
JP3802810B2 (en) | 2006-07-26 |
EP1143023A1 (en) | 2001-10-10 |
DE60020522T2 (en) | 2005-11-24 |
EP1143023A4 (en) | 2003-01-02 |
KR20010080751A (en) | 2001-08-22 |
EP1143023B1 (en) | 2005-06-01 |
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