EP1520912B1 - Acier présentant une excellente ténacité de la zone affectée thermiquement par soudage - Google Patents

Acier présentant une excellente ténacité de la zone affectée thermiquement par soudage Download PDF

Info

Publication number
EP1520912B1
EP1520912B1 EP04026201A EP04026201A EP1520912B1 EP 1520912 B1 EP1520912 B1 EP 1520912B1 EP 04026201 A EP04026201 A EP 04026201A EP 04026201 A EP04026201 A EP 04026201A EP 1520912 B1 EP1520912 B1 EP 1520912B1
Authority
EP
European Patent Office
Prior art keywords
steel
toughness
oxide particles
haz
steels
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.)
Expired - Lifetime
Application number
EP04026201A
Other languages
German (de)
English (en)
Other versions
EP1520912A3 (fr
EP1520912A2 (fr
Inventor
Masanori Nippon Steel Corp. Minagawa
Toshihiko Nippon Steel Corp. Koseki
Yuji Nippon Steel Corp. Funatsu
Jun Nippon Steel Corp. Ohtani
Tomohiko Nippon Steel Corp. Hada
Tadashi Nippon Steel Corp. Ishikawa
Masaaki Nippon Steel Corp. Nagahara
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Steel Corp
Original Assignee
Nippon Steel Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from JP2000033242A external-priority patent/JP2001226739A/ja
Application filed by Nippon Steel Corp filed Critical Nippon Steel Corp
Publication of EP1520912A2 publication Critical patent/EP1520912A2/fr
Publication of EP1520912A3 publication Critical patent/EP1520912A3/fr
Application granted granted Critical
Publication of EP1520912B1 publication Critical patent/EP1520912B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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
    • 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
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • 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
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium

Definitions

  • This invention relates to a steel for a welded structure excellent in the toughness of a weld heat-affected zone (hereinafter referred to as "HAZ”) used for ships, marine construction, medium and high-rise buildings and so on.
  • HZ weld heat-affected zone
  • Japanese Unexamined Patent Publication No. H3-264614 proposes a method of improving the toughness of a HAZ by using the multiphase precipitates of Ti nitrides and MnS as the nuclei of ferrite transformation.
  • Japanese Unexamined Patent Publication No. H4-143246 proposes a method of improving the toughness of a HAZ by using the multiphase precipitates of Ti nitrides and BN as the nuclei of the precipitation of intergranular ferrite.
  • steels containing Ti oxides are used in various fields of steel plates, sections and the like.
  • a steel containing Ti oxides is very effective for improving the toughness of a high heat input HAZ, and the application of the technology to a high tensile steel is promising.
  • the principle is as follows: Ti nitrides, MnS and the like precipitate using Ti oxides, which are stable even at the melting temperature of a steel, as precipitation sites during the temperature drop after welding; then fine ferrite forms using the precipitated Ti nitrides, MnS and the like as the sites of the formation; and, as a result, the formation of coarse ferrite detrimental to toughness is suppressed and, thus, the toughness is prevented from deteriorating.
  • the cause is the coarsening and agglomeration of Ti oxides and, when it is attempted to increase the number of Ti oxides, coarse Ti oxides 5 ⁇ m or more in diameter, namely so-called inclusions, increase. Inclusions 5 ⁇ m or more in diameter are harmful since they serve as starting points of the fracture of a structure, leading to the deterioration of toughness. To further improve the toughness of a HAZ, therefore, it is necessary to use oxides not prone to coarsen or agglomerate but which are apt to disperse in a steel in finer grains than Ti oxides.
  • the method of adding Ti to molten steel substantially not containing strongly deoxidizing elements such as Al is often employed. It is difficult, however, to control the number and dispersion of Ti oxides in a steel by simply adding Ti to molten steel and, moreover, it is also difficult to control the number and dispersion of the precipitates of TiN, MnS and the like. As a consequence, in a steel wherein the Ti oxides are dispersed solely by means of the deoxidation by Ti, there are problems of causing, for instance, an insufficient number of Ti oxides, toughness variation in the thickness direction of a steel plate and the like.
  • the upper limit of Al amount is set at a very low figure of 0.007%.
  • the toughness of a base metal may deteriorate caused by an insufficient amount of AlN precipitates or the like.
  • the toughness of a weld metal may deteriorate.
  • Japanese Unexamined Patent Publication No. H6-293937 proposes a technique of utilizing Ti-Al composite oxides formed by adding Al immediately after adding Ti. It is possible, by this technique, to significantly improve the toughness of a HAZ under high heat input welding. Lately, however, shipbuilding and construction industries are promoting a further increase in weld heat input to 200 kJ/cm or more or even to 1,000 kJ/cm and, as a consequence, a steel having higher HAZ toughness is sought. In this situation, the improvement of toughness in the vicinity of a weld fusion zone is particularly required.
  • the document JP-A-10-183295 discloses a steel exhibiting an improved toughness in the weld heat affected zone with the composition in weight %: C 0.03-0.18%, Si at most 0.50%, Mn 0.4-2.0%, P at most 0.02%, S 0.001-0.01 %, Al 0.005-0.02%, Ti 0.005-0.02%, Ca 0.0005- 0.003% and N of 0.002-0.006% by weight, balance Fe with unvoidable impurities.
  • the steel of the Japanese document contains compound oxides with Ca, Ti and Al for which the diameter is 0.01-1.0 micron, at 5.10 3 - 10 5 per mm 2 .
  • the object of the present invention is, in order to significantly improve the properties of a HAZ even under the above ultra-high heat input welding, to provide a steel excellent in the toughness of a weld heat-affected zone, wherein a HAZ excellent in toughness can be realized by further suppressing the coarsening of austenite grains when the steel is heated for a long time at a high temperature.
  • the present invention has been established for solving the above problems, and is defined in the claims.
  • the present invention is explained in detail hereafter.
  • the present inventor studied the method of making reheated austenite grains fine in a HAZ, which is heated to 1,400°C or higher, using an oxide.
  • volume percentage of the dispersed grains The higher the volume percentage of the dispersed grains and the larger the diameter of each of them, the larger the effect of the dispersed grains to pin the crystal grain boundaries. It has to be noted, however, that there is an upper limit to the volume percentage of the dispersed grains, determined by the concentrations of the component elements of the grains contained in the steel in question. Therefore, supposing that the volume percentage is constant, a good pinning effect is obtained when the diameter of the grains is not very large. From this viewpoint, the present inventors carried out studies on how to increase the volume percentage of oxides and how to obtain an adequate grain size.
  • the present inventors discovered that it was possible to increase the volume percentage of oxides, or the amount of oxides, when Ca at 3% or more and Al at 1% or more were contained in the composition of the oxide particles formed in a steel. Based on this result, the present invention stipulated that the oxide particles in a steel contained at least Ca, Al and O in their composition, and that the oxide particles contained, in the mass percentage of the elements excluding O, Ca at 3% or more and Al at 1% or more.
  • the present invention stipulated that the oxide particles in a steel contained at least Ca, Al, Mg and O in their composition, and that, in the mass percentage of the elements excluding O, the oxide particles contained Ca at 5% or more, Al at 5% or more and Mg at 1% or more.
  • the present inventors discovered that a further increases in the volume percentage of the dispersed grains could be brought about through the combined effect of oxides and sulfides when sulfides such as CaS and MgS precipitated around oxides particles.
  • the present invention stipulated that the particles in a steel contained at least Ca, Al, O and S in their composition, and that, in the mass percentage of the elements excluding O, the particles contained Ca at 5% or more, Al at 5% or more and S at 1% or more, otherwise, that the particles in a steel contained at least Ca, Al, Mg, O and S in their composition, and that, in the mass percentage of the elements excluding O, the particles contained Ca at 5% or more, Al at 5% or more, Mg at 1% or more and S at 1% or more.
  • the present inventors confirmed that the effects of the present invention remained unaffected in the above case, even when the oxide particles contained Mg and/or REM, having a deoxidizing strength rated between Al and Ca, as a component element or component elements in the balance of the elements whose contents were specified above.
  • the present inventors also confirmed that the effects of the present invention were not hindered even when the particles contained deoxidizing elements milder than Al, such as Si, Mn and Ti, unavoidably included in the oxide particles and/or impurity elements, such as S, inevitably combining with Ca and so on.
  • the effect of pinning crystal grain boundaries by dispersed grains increases as the volume percentage of the dispersed grains increases and the size of each of the grains becomes larger.
  • the present inventors reasoned that, when the volume percentage of the dispersed grains was constant, the number of the oxide particles would increase as the size of each of the particles became smaller and, as a consequence, pinning effect would increase, and that, when the grain size was too small, the proportion of the crystal grain boundaries occupied by the dispersed grains would decrease and, as a result, the pinning effect would also decrease.
  • the present inventors discovered that the pinning effect was the largest when the grain size was from 0.005 to 2.0 ⁇ m. It was also made clear that the pinning force for arresting the migration of austenite grain boundaries became stronger as the size of the dispersed grains increased. Thus, the present inventors discovered that, among the dispersed grains having grain sizes from 0.005 to 2.0 ⁇ m, those having grain sizes from 0.1 to 2.0 ⁇ m were particularly effective. Pinning effect decreases gradually when the grain size decreases to below 0.1 ⁇ m and, when it is below 0.005 ⁇ m, little of the pinning effect appears.
  • the oxide particles larger than 2.0 ⁇ m have pinning effect, they sometimes serve as the starting points of brittle fracture and, for this reason, they are undesirable from the viewpoint of the material properties of a steel.
  • the present invention stipulates that the required diameter of the oxide particles is from 0.005 to 2.0 ⁇ m, preferably from 0.1 to 2.0 ⁇ m.
  • the present inventors studied the number of pinning grains required for securing a desired toughness of a HAZ.
  • a HAZ toughness required of a steel material is different in a complicated manner depending on the application of the steel material and the method of welding employed in the application.
  • the present inventors discovered that, in order to satisfy a HAZ toughness, for example, of 50 J or more in terms of the absorbed energy at a test temperature of -40°C, corresponding to the toughness level required when a high strength steel for ship construction was welded under a high heat input, which was considered to be a case where especially stringent property requirements were applied, it was necessary that the density of oxide particles 0.005 to 2.0 ⁇ m in circle-equivalent diameter was 100 pieces/mm 2 or more, as shown in Fig. 1.
  • an appropriate upper limit of the density of the oxide particles is 3,000 pieces/mm 2 .
  • the size and number of the oxide particles can be measured, for instance, in the following manner.
  • An extracted replica is produced from a sample taken from a base steel plate, and it is observed at 20 or more visual fields, namely 1,000 ⁇ m 2 or more in terms of the total observation area, under a magnification of ⁇ 10,000 using an electron microscope.
  • the size of the particles are determined, for instance, by calculating circle-equivalent diameters of the particles based on micrographs of the particles.
  • the extracted replica may be produced from any portion from the surface layer to the thickness center of a steel plate. A lower magnification may be used if the oxide particles can be observed adequately.
  • the oxide particles form during the deoxidation process of molten steel.
  • the oxides forming at this stage are called primary oxides.
  • Ti-Al-Ca oxides form as the temperature of the molten steel falls during the stages of casting and solidification.
  • the oxides forming at these stages are called secondary oxides. Either primary oxides or secondary oxides may be used for the purpose of the present invention.
  • the present inventors proceeded with further studies for significantly increasing the effects of improving toughness by refining a HAZ structure yet more. As a result, they discovered that, when the reheated austenite grains were made finer by dispersing fine oxide grains in a great amount, an addition of B was very effective for suppressing the growth of ferrite at the grain boundaries and triple boundaries during the process in which a HAZ structure was formed.
  • C is an effective component for increasing steel strength and, as such, the lower limit of its content is set at 0.03%. Since its excessive addition remarkably deteriorates the weldability, HAZ toughness and so on of a steel material, the upper limit of its content is set at 0.18%.
  • Si is a component necessary for securing the strength of base metal, deoxidizing steel and so on, but the upper limit of its content is set at 0.5% in order to prevent the toughness of a HAZ from lowering through its hardening.
  • Mn is an effective component for securing the strength and toughness of base metal and, as such, it has to be added at 0.4% or more, but the upper limit of its content is set at 2.0% in order to control the toughness, cracking property and so on of welded joints within respective tolerable ranges.
  • Al is an important deoxidizing element and, for this reason, the lower limit of its content is set at 0.005%.
  • the upper limit of its content is set at 0.04%.
  • Ti is added at 0.005% or more for the purpose of forming Ti nitrides through the combination with N.
  • the HAZ toughness is lowered and, for this reason, the upper limit of its content is set at 0.03%.
  • B is an effective element, when it is in a solute state, for suppressing the growth of ferrite forming at the boundaries of reheated austenite grains and, for this reason, B of at least 0.0005% is added.
  • B When it is added in a great amount, however, the toughness of a steel material is deteriorated and, therefore, the upper limit of its content is set at 0.003%.
  • Cu is effective for enhancing the strength of a steel material but, when it is added in excess of 1.0%, the HAZ toughness is lowered and, therefore, the upper limit of its content is set at 1.0%.
  • Ni is effective for enhancing the strength and toughness of a steel material but, as the increase in its addition increases production costs, the upper limit of its content is set at 1.5%.
  • Nb is an effective element for enhancing the strength and toughness of base metal through the improvement of hardenability but, since its excessive addition deteriorates the toughness of a HAZ remarkably, the upper limit of its content is set at 0.04%.
  • V, Cr and Mo have the same effects as Nb does and, for this reason, the upper limits of their contents are set at 0.1, 0.6 and 0.6%, respectively.
  • REM has a deoxidizing strength in molten steel second to Ca and also a function of helping Ca form fine oxide grains, but its addition is more costly than the addition of Ca and, when added excessively, it forms coarse inclusions to deteriorate the toughness of a HAZ and a steel plate. For this reason, the upper limit of its content is set at 0.05%.
  • Table 2 shows the composition of oxide particles, the number of the oxide particles 0.005 to 2.0 ⁇ m in diameter, the rolling conditions of the steel plates, the characteristics of base metal and the toughness of the HAZ.
  • a Charpy impact value for evaluating the HAZ toughness is the average value of 9 test pieces, each of the values being measured at the portion of a HAZ located 1 mm away from a fusion line.
  • steels 1 to 8 according to the present invention have excellent HAZ toughness compared with comparative steels: they are quite excellent in the HAZ toughness at -40°C, as the oxide particle size, the number of oxide particles and the amounts of their components are within the respective ranges specified in the present invention. It is also clear from the table that, among the steels according to the present invention, invented steels 3, 4, 5, 6, and 8 containing the oxide particles 0.1 to 2.0 ⁇ m in diameter within the range from 100 to 3,000 pieces/mm 2 , invented steels 2, 4, 5, 6, 7 and 8 having the oxide particles containing Mg of 1% or more, and invented steels 3, 4 and 5 having the oxide particles containing S of 1% or more are superior in the HAZ toughness to the other invented steels.
  • the content of Al in the oxide particles and the number of oxide particles are below the respective lower limits according to the present invention.
  • the Charpy test for evaluating the HAZ toughness was done at -40°C, and each of the impact values in the table is the average value of 9 test pieces, each of the values being measured at the portion of a HAZ located 1 mm away from a bond.
  • invented steels 17 to 24 have excellent HAZ toughness compared with comparative steels.
  • the density of the oxide particles 0.005 to 2.0 ⁇ m in diameter containing Ca and Al by respective prescribed contents is within the range from 100 to 3,000 pieces/mm 2 and, thanks to this, the austenite grain size of the HAZ structure of these steels is smaller compared with that of comparative steels, and the ferrite at the grain boundaries or triple boundaries of austenite grains is also small owing to the effect of B.
  • the Charpy absorbed energy value at -40°C of each of these steels far exceeds 50 J, which is the average absorbed energy value generally required of steel structures from the viewpoint of fracture mechanics, and thus the HAZ toughness is quite excellent, as seen in the table.
  • the density of the oxide particles 0.1 to 2.0 ⁇ m in diameter is 100 pieces/mm 2 or more and, as a consequence, the austenite grain size is relatively small compared with that of steels 19 and 22, and the Charpy absorbed energy value is high.
  • a HAZ toughness value is the average value of the results of Charpy tests at -40°C obtained by applying the Charpy tests to 9 test pieces, each of the values being measured at the portion of a HAZ located 1 mm away from the bond of the steel plates after the welding.
  • invented steels 32 to 39 have excellent HAZ toughness compared with comparative steels.
  • the density of the oxide particles 0.005 to 2.0 ⁇ m in diameter containing Ca and Al by respective prescribed contents is within the range from 100 to 3,000 pieces/mm 2 and, thanks to this, the austenite grain size of the HAZ structure of these steels is smaller compared with that of comparative steels, and the ferrite at the grain boundaries or triple boundaries of austenite grains is also small owing to the effect of B.
  • the Charpy absorbed energy value at -40°C of each of these steels far exceeds 50 J, which is the average value generally required of steel structures from the viewpoint of fracture mechanics, and thus the HAZ toughness is quite excellent, as seen in the table.
  • the density of the oxide particles 0.1 to 2.0 ⁇ m in diameter is 100 pieces/mm 2 or more and, as a consequence, the austenite grain size is relatively small compared with that of steels 34 and 37, and the Charpy absorbed energy value is high.
  • the present invention is a steel plate excellent in toughness at a welding joint even in high heat input welding or ultra-high heat input welding with a heat input of 200 kJ/cm 2 or more, and is applicable to general steel materials for welded structures used for ships, marine construction, medium and high-rise buildings, bridges and so on and also to material steel plates for pipes, bars, long steel products, hot-rolled steel sheets and the like.
  • a significant improvement in the toughness of a welded joint is obtained in any of these applications.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Heat Treatment Of Steel (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Nonmetallic Welding Materials (AREA)

Claims (6)

  1. Acier présentant une excellente ténacité d'une zone affectée thermiquement par soudage qui contient, en masse
    C: 0,03 à 0,18%,
    Si : 0,5 % ou moins,
    Mn : 0,4 à 2,0 %,
    P : 0,02 % ou moins,
    S : 0,02 % ou moins,
    Al : 0,005 à 0,04 %,
    Ti : 0,005 à 0,03 %,
    Ca : 0,0005 à 0,003 %,
    N : 0,0005 à 0,007 %,
    et facultativement un ou plusieurs choisis parmi B : 0,0005 à 0,003 %, Cu : 1,0 % ou moins, Ni : 1,5 % ou moins, Nb : 0,04 % ou moins, V : 0,1 % ou moins, Cr : 0,6 % ou moins, Mo : 0,6 % ou moins, et REM : 0,05 % ou moins, le reste étant constitué de Fe et d'impuretés inévitables ; la densité, définie par particules par surface unitaire, de particules d'oxyde de 0,005 à 2,0 µm dans un diamètre équivalent à celui d'un cercle contenues dans l'acier est de 100 à 3 000 particules/ mm2, les particules d'oxyde contiennent au moins Ca, Al et 0 dans leur composition ; et, dans le pourcentage en masse des éléments à l'exception de O, les particules d'oxyde contiennent Ca à 5 % ou plus et Al à 5 % ou plus, facultativement S à 1 % ou plus, facultativement Mg à 1 % ou plus, et S à 1 % ou plus, le reste étant constitué de Fe et d'impuretés inévitables, ou, lorsque ledit acier contient B, Ca à 3 % ou plus et Al à 1 % ou plus , le reste étant constitué de Fe et d'impuretés inévitables ; et l'acier répond à l'expression
    - 0,0005 ≤ EN ≤ 0,002, à condition que EN soit donné par l'équation équivalente EN = (% N) - 0,292 (% Ti) - 1,292.
  2. Acier présentant une excellente ténacité d'une zone affectée thermiquement par soudage selon la revendication 1, caractérisé en ce que : les particules d'oxyde dans l'acier contiennent au moins Ca, Al, et S dans leur composition ; et dans le pourcentage en masse des éléments à l'exception de O, les particules d'oxyde contiennent Ca à 5 % ou plus, Al à 5 % ou plus et S à 1 % ou plus.
  3. Acier présentant une excellente ténacité d'une zone affectée thermiquement par soudage selon la revendication 1 ou 2, caractérisé en ce que : les particules d'oxyde dans l'acier contiennent au moins Ca, Al, Mg, O et S dans leur composition ; et dans le pourcentage en masse des éléments à l'exception de O, les particules d'oxyde contiennent Ca à 5 % ou plus, Al à 5 % ou plus, Mg à 1 % ou plus et S à 1 % ou plus.
  4. Acier présentant une excellente ténacité d'une zone affectée thermiquement par soudage selon l'une quelconque des revendications 1 à 3, caractérisé en ce que l'acier répond à l'expression - 0,004 ≤ EN ≤ - 0,0005, à condition que EN soit donné par l'équation équivalente EN = (% N) - 0,292 (% Ti) - 1,292.
  5. Acier présentant une excellente ténacité d'une zone affectée thermiquement par soudage selon l'une quelconque des revendications 1 à 3, caractérisé en ce que l'acier répond à l'expression 0 ≤ EN ≤ 0,002, à condition que EN soit donné par l'équation équivalente EN = (% N) - 0,292 (% Ti) - 1,292.
  6. Acier présentant une excellente ténacité d'une zone affectée thermiquement par soudage selon l'une quelconque des revendications 1 à 5, caractérisé en ce que le diamètre équivalent à celui d'un cercle des particules d'oxyde dans l'acier est de 0,1 à 2,0 µm.
EP04026201A 2000-02-10 2000-11-13 Acier présentant une excellente ténacité de la zone affectée thermiquement par soudage Expired - Lifetime EP1520912B1 (fr)

Applications Claiming Priority (7)

Application Number Priority Date Filing Date Title
JP2000033241 2000-02-10
JP2000033242 2000-02-10
JP2000033241 2000-02-10
JP2000033242A JP2001226739A (ja) 2000-02-10 2000-02-10 溶接熱影響部靭性に優れた鋼材
JP2000068210 2000-03-13
JP2000068210 2000-03-13
EP00974966A EP1262571B1 (fr) 2000-02-10 2000-11-13 Acier a zone affectee thermiquement par soudage presentant une excellente tenacite

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
EP00974966A Division EP1262571B1 (fr) 2000-02-10 2000-11-13 Acier a zone affectee thermiquement par soudage presentant une excellente tenacite

Publications (3)

Publication Number Publication Date
EP1520912A2 EP1520912A2 (fr) 2005-04-06
EP1520912A3 EP1520912A3 (fr) 2005-04-27
EP1520912B1 true EP1520912B1 (fr) 2007-01-17

Family

ID=27342318

Family Applications (2)

Application Number Title Priority Date Filing Date
EP04026201A Expired - Lifetime EP1520912B1 (fr) 2000-02-10 2000-11-13 Acier présentant une excellente ténacité de la zone affectée thermiquement par soudage
EP00974966A Expired - Lifetime EP1262571B1 (fr) 2000-02-10 2000-11-13 Acier a zone affectee thermiquement par soudage presentant une excellente tenacite

Family Applications After (1)

Application Number Title Priority Date Filing Date
EP00974966A Expired - Lifetime EP1262571B1 (fr) 2000-02-10 2000-11-13 Acier a zone affectee thermiquement par soudage presentant une excellente tenacite

Country Status (4)

Country Link
EP (2) EP1520912B1 (fr)
KR (1) KR100514667B1 (fr)
DE (2) DE60021919T2 (fr)
WO (1) WO2001059167A1 (fr)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3699077B2 (ja) * 2002-10-29 2005-09-28 株式会社日本製鋼所 溶接熱影響部の低温靭性に優れたクラッド鋼板用母材および該クラッド鋼板の製造方法
JP4972451B2 (ja) * 2007-04-20 2012-07-11 株式会社神戸製鋼所 溶接熱影響部および母材の低温靭性に優れた低降伏比高張力鋼板並びにその製造方法
JP4399018B1 (ja) 2008-07-15 2010-01-13 新日本製鐵株式会社 溶接熱影響部の靭性に優れた鋼板
US9403242B2 (en) 2011-03-24 2016-08-02 Nippon Steel & Sumitomo Metal Corporation Steel for welding
WO2013007729A1 (fr) * 2011-07-10 2013-01-17 Tata Steel Ijmuiden Bv Bande d'acier haute résistance laminée à chaud avec résistance élevée au ramollissement haz et son procédé de production
EP2784168B1 (fr) * 2011-11-25 2016-11-23 Nippon Steel & Sumitomo Metal Corporation Matériau à base d'acier soudable
KR101719943B1 (ko) * 2013-03-12 2017-03-24 제이에프이 스틸 가부시키가이샤 다층 용접 조인트 ctod 특성이 우수한 후강판 및 그 제조 방법
CN103320692B (zh) 2013-06-19 2016-07-06 宝山钢铁股份有限公司 超高韧性、优良焊接性ht550钢板及其制造方法
CN103320693B (zh) 2013-06-19 2015-11-18 宝山钢铁股份有限公司 抗锌致裂纹钢板及其制造方法

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08158006A (ja) * 1994-12-06 1996-06-18 Kobe Steel Ltd 溶接熱影響部の靭性が優れた高強度鋼
JP3323414B2 (ja) * 1996-12-19 2002-09-09 新日本製鐵株式会社 大入熱溶接の熱影響部靭性の優れた鋼材およびその製造方法
JP3599556B2 (ja) * 1998-02-16 2004-12-08 株式会社神戸製鋼所 母材および大入熱溶接熱影響部の靱性に優れた高張力鋼板およびその製造方法
JP3507339B2 (ja) * 1998-04-15 2004-03-15 新日本製鐵株式会社 溶接熱影響部の靱性に優れた鋼板

Also Published As

Publication number Publication date
DE60021919T2 (de) 2006-06-08
EP1520912A3 (fr) 2005-04-27
KR20020073579A (ko) 2002-09-27
DE60033070T2 (de) 2007-05-31
WO2001059167A1 (fr) 2001-08-16
EP1262571A1 (fr) 2002-12-04
KR100514667B1 (ko) 2005-09-14
EP1520912A2 (fr) 2005-04-06
EP1262571A4 (fr) 2003-03-26
EP1262571B1 (fr) 2005-08-10
DE60033070D1 (de) 2007-03-08
DE60021919D1 (de) 2005-09-15

Similar Documents

Publication Publication Date Title
EP0839921B1 (fr) Acier possedant une plus grande solidite dans les zones affectees par la chaleur de soudures
JP3898814B2 (ja) 低温靱性に優れた高強度鋼用の連続鋳造鋳片およびその製造法、および低温靱性に優れた高強度鋼
EP3533891A1 (fr) Acier pour soudage à apport de chaleur élevé
EP1520912B1 (fr) Acier présentant une excellente ténacité de la zone affectée thermiquement par soudage
EP1143023B1 (fr) Acier pour structure soudee dont la tenacite de zone thermiquement affectee ne depend pas d'un apport de chaleur, et procede de production associe
EP3378962B1 (fr) Matériau en acier soudé avec apport de chaleur élevé
EP1052303A2 (fr) Produit d'acier à haute résistance à la traction et à ductilité excellente dans la zone affectée par la chaleur, pour le soudage avec apport de chaleur élevée
JP2001342537A (ja) 溶接熱影響部靭性の優れた鋼材およびその製造方法
JP3323414B2 (ja) 大入熱溶接の熱影響部靭性の優れた鋼材およびその製造方法
JP2003313628A (ja) 溶接熱影響部靭性に優れた鋼材
JP3464567B2 (ja) 溶接熱影響部靱性の優れた溶接構造用鋼材
JP2688312B2 (ja) 高強度高靭性鋼板
JP2002371338A (ja) レーザー溶接部の靭性に優れた鋼
JP2930772B2 (ja) 溶接熱影響部靱性の優れた高マンガン超高張力鋼
JP3736209B2 (ja) 溶接部靭性に優れた高張力鋼及びその製造方法
JPH07278736A (ja) 溶接熱影響部靱性の優れた鋼材
JP3616609B2 (ja) 溶接熱影響部靭性の優れた鋼材
JP3464566B2 (ja) 溶接熱影響部靱性の優れた低温用鋼材
JPS621842A (ja) 溶接部靭性の優れた強靭性高張力鋼
JP4261968B2 (ja) 溶接熱影響部靭性の優れた鋼材およびその製造方法
JP3477054B2 (ja) 溶接熱影響部靭性の優れた鋼板
JP2001226739A (ja) 溶接熱影響部靭性に優れた鋼材
JP3224677B2 (ja) 溶接用低温用鋼
WO2022097588A1 (fr) Tôle d'acier et procédé de fabrication de celle-ci
JP3502851B2 (ja) 溶接施工性および溶接継手靭性に優れた６００ＭＰａ級鋼

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AC Divisional application: reference to earlier application

Ref document number: 1262571

Country of ref document: EP

Kind code of ref document: P

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): DE FR

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): DE FR

17P Request for examination filed

Effective date: 20050615

AKX Designation fees paid

Designated state(s): DE FR

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AC Divisional application: reference to earlier application

Ref document number: 1262571

Country of ref document: EP

Kind code of ref document: P

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR

REF Corresponds to:

Ref document number: 60033070

Country of ref document: DE

Date of ref document: 20070308

Kind code of ref document: P

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20071018

REG Reference to a national code

Ref country code: DE

Ref legal event code: R081

Ref document number: 60033070

Country of ref document: DE

Owner name: NIPPON STEEL & SUMITOMO METAL CORPORATION, JP

Free format text: FORMER OWNER: NIPPON STEEL CORP., TOKIO/TOKYO, JP

Effective date: 20130227

Ref country code: DE

Ref legal event code: R082

Ref document number: 60033070

Country of ref document: DE

Representative=s name: VOSSIUS & PARTNER, DE

Effective date: 20130227

Ref country code: DE

Ref legal event code: R082

Ref document number: 60033070

Country of ref document: DE

Representative=s name: VOSSIUS & PARTNER PATENTANWAELTE RECHTSANWAELT, DE

Effective date: 20130227

REG Reference to a national code

Ref country code: FR

Ref legal event code: CA

Effective date: 20130913

Ref country code: FR

Ref legal event code: CD

Owner name: NIPPON STEEL & SUMITOMO METAL CORPORATION, JP

Effective date: 20130913

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 16

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 17

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 18

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 19

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20181030

Year of fee payment: 19

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20181011

Year of fee payment: 19

REG Reference to a national code

Ref country code: DE

Ref legal event code: R082

Ref document number: 60033070

Country of ref document: DE

Representative=s name: VOSSIUS & PARTNER PATENTANWAELTE RECHTSANWAELT, DE

Ref country code: DE

Ref legal event code: R081

Ref document number: 60033070

Country of ref document: DE

Owner name: NIPPON STEEL CORPORATION, JP

Free format text: FORMER OWNER: NIPPON STEEL & SUMITOMO METAL CORPORATION, TOKYO, JP

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 60033070

Country of ref document: DE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20200603

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20191130