EP2977479A1 - Matériau acier présentant une résistance supérieure dans une zone affectée par la chaleur de soudage - Google Patents

Matériau acier présentant une résistance supérieure dans une zone affectée par la chaleur de soudage Download PDF

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EP2977479A1
EP2977479A1 EP14767775.1A EP14767775A EP2977479A1 EP 2977479 A1 EP2977479 A1 EP 2977479A1 EP 14767775 A EP14767775 A EP 14767775A EP 2977479 A1 EP2977479 A1 EP 2977479A1
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rem
steel material
mass
oxides
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EP2977479A4 (fr
EP2977479B1 (fr
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Takashi SUGITANI
Masaki Shimamoto
Hidenori Nako
Sei Kimura
Shinsuke Sato
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Kobe Steel Ltd
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Kobe Steel Ltd
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    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
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    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
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    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
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    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/004—Dispersions; Precipitations
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    • 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
    • C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0226—Hot rolling

Definitions

  • the present invention relates to a thick steel plates suitable to be used in welded structures such as ships, constructions, and bridges, and in particular, to a steel material that achieves superior HAZ toughness even for high heat input welding.
  • a welding heat affected zone (hereinafter, also referred to as a HAZ) exposed to welding heat generally becomes high while welding is being performed, regardless of whether the amount of heat of the welding is large or small, and hence the crystal grain of the steel material is likely to coarsen.
  • the temperature of a HAZ becomes higher, thereby causing a cooling time to be longer. It is already known that, because a long cooling time in a high temperature causes the formation of a brittle upper bainite structure or the formation of an embrittlement structure, such as island martensite, in a HAZ to be promoted, the HAZ toughness of a steel material may be decreased.
  • Patent Document 1 is intended to provide a steel material having superior HAZ toughness and a production method thereof. Specifically, the production method disclosed in Patent Document 1 is said that, fine sulfides are dispersed and the particles in a HAZ structure heated to no lower than 1400°C are made fine by adding Mg and/or REM in addition to Ca having a strong sulfide formation ability in molten steel, so that fine oxides are formed, thereby allowing the HAZ toughness good even for high heat input welding of no less than 200 kJ/cm to be achieved.
  • Patent Document 2 is intended to provide steel for high strength welded structure, the steel having superior base plate toughness and superior welded zone HAZ toughness, and a production method thereof. Specifically, the production method disclosed in Patent Document 2 is intended to cause heated ⁇ particles in a base plate to be fine and further to cause heated ⁇ particles in a HAZ to be fine regardless of welding heat input, by adding one or more of Mg, Ca, and REM after Ti is added or simultaneously when Ti is added such that oxides and sulfides are finely dispersed. The production method of Patent Document 2 is said that steel for high strength welded structure, the steel having good base plate toughness and good welded zone HAZ toughness, can be produced as an effect created by these two particle refinements.
  • Patent Document 3 is intended to provide a thick steel plate having superior HAZ toughness for super-high heat input welding and a production method thereof. Specifically, in the production method of Patent Document 3, the form of the dendrite formed in a solidification process is further controlled in addition to an adjustment in which the particle compositions of oxides and sulfides, etc., in molten steel are adjusted. Thereby, the production method of Patent Document 3 is said that, austenite particles can be made fine even in a HAZ for super-high heat input welding of no less than 300 kJ/cm by dispersing the dispersed particles in a steel plate more uniformly and finely than related art, thereby allowing HAZ toughness to be remarkably improved.
  • Patent Document 4 is intended to provide a high-strength steel plate having a strength of X100 or more in the API standards, the steel plate having good HAZ toughness.
  • the high-strength steel plate of Patent Document 4 contains (1) TiN-based fine precipitates containing Mg-based oxides having a size of no greater than 0.1 ⁇ m by limiting the amounts of Ti, Mg, REM, Al, S, and N, thereby suppressing the coarsening of ⁇ particles even in the vicinity of a fusion line.
  • this high-strength steel plate is said to allow the structure to be made fine across a HAZ and HAZ toughness to be improved by containing (2) complexes between oxides mainly formed by Ti, Mg, and REM, the oxides having a size of no less than 0.1 ⁇ m, and MnS, so that IGF is produced from the insides of relatively small ⁇ particles.
  • Patent Document 5 is intended to present a non-heat treated high-tensile steel material having good base plate toughness and having good HAZ toughness. Specifically, the non-heat treated high-tensile steel material of Patent Document 5 is controlled to contain, in units of weight%, 20-90% of Ti oxides, 5-50% of the total of CaO and REM oxides, and no greater than 70% of Al 2 O 3 as optimal composition ranges of optimal oxide-based inclusions.
  • the non-heat treated high-tensile steel material can effectively utilize an ability of suppressing the crystal grain coarsening of the inclusions (pinning effect) without causing nozzle clogging or production of a harmful inclusion cluster, and hence HAZ toughness can be improved, and further the toughness and strength of a base plate can be improved by optimally dispersing TiN or further VN.
  • each of Patent Documents 1-5 discloses that a decrease in HAZ toughness, occurring due to welding heat, can be dealt with; however, it is difficult to improve HAZ toughness for further high heat input welding, even when any technique is used.
  • the technique disclosed in each of Patent Documents 1-3 is intended to make a HAZ structure fine by the pinning effect of an oxysulfide, but each of the Patent Documents never refers to an effect of making a structure fine by intra-granular transformation resulting from the oxysulfide, and hence the technique cannot be said as being a technique for dealing with further high heat input welding.
  • Patent Document 4 refers to structure transformation originating at an oxide, but a means for a coarse oxide, etc., is not described; and accordingly the possibility that HAZ toughness may be decreased due to the production of a coarse oxide cannot be excluded, and hence the technique thereof cannot be said as being a technique for dealing with further high heat input welding.
  • the technique disclosed in Patent Document 5 is one in which a HAZ structure is made fine by the pinning effect of an oxysulfide, but is not one in which the control of the structure transformation originating at an oxysulfide is taken into consideration, and accordingly the technique cannot be said as being a technique for dealing with further high heat input welding.
  • the present invention has been made in view of the aforementioned problems, and an object of the invention is to provide a steel material having superior toughness at welding heat affected zone (HAZ toughness) for high heat input welding.
  • HZ toughness welding heat affected zone
  • a technical means for solving the problems in the invention is a steel material containing, in units of mass%, 0.02-0.13% of C, 0.05-0.5% of Si, 1.0-2.5% of Mn, no greater than 0.03% of P (exclusive of 0%), no greater than 0.01% of S (exclusive of 0%), 0.002-0.040% of Al, 0.005-0.040% of Ti, 0.0003-0.020% of Zr, 0.0003-0.020% of REM, 0.0003-0.0080% of Ca, 0.0030-0.010% of N, and 0.0003-0.0050% of O, the steel material having a remainder comprising iron and unavoidable impurities and having superior toughness at welding heat affected zone, in which: the steel material contains a complex oxide containing REM, Zr, Ti, Al, Ca, and S; the complex oxide in the steel material has no greater than 5.0/mm 2 of oxides having a circular-equivalent diameter of greater than 3
  • a steel material having superior toughness at welding heat affected zone (HAZ toughness) for high heat input welding, can be obtained.
  • the steel material according to the present embodiment is a steel material exerting superior toughness of a welding heat affected zone (HAZ, Heat Affected Zone) that has been affected by very large welding energy in which welding heat input exceeds, for example, 60 kJ/mm.
  • HAZ welding heat affected zone
  • HAZ toughness the toughness of a HAZ
  • the steel material according to the present embodiment can stably achieve good HAZ toughness even for high heat input welding by producing a predetermined amount of complex oxides (oxysulfides containing Al, Ti, Zr, REM, Ca, and S), the complex oxide serving as a nucleus for intra-granular transformation, with the size and S concentration thereof being properly controlled.
  • complex oxides oxysulfides containing Al, Ti, Zr, REM, Ca, and S
  • the steel material is characterized as follows: the number of coarse complex oxides having a circular-equivalent diameter of greater than 3 ⁇ m, which adversely affect an improvement in HAZ toughness, is significantly controlled; and complex oxides having a circular-equivalent diameter of 0.1-3 ⁇ m, which is useful for an improvement in HAZ toughness, and having the composition and particle size thereof properly controlled are contained such that the number of the complex oxides is no less than a predetermined value.
  • the steel material according to the embodiment can exert stably superior HAZ toughness even for welding with large heat input.
  • the steel material according to the present embodiment having the aforementioned characteristic, can be obtained by adding, for example, in the secondary refining of molten steel, each element so as to have the chemical component composition described below.
  • the steel material according to the embodiment (hereinafter, simply referred to as the present steel material) contains: 0.02-0.13% of Carbon (C), 0.05-0.5% of Silicon (Si), 1.0-2.5% of manganese (Mn), no greater than 0.03% of phosphorus (P) (exclusive of 0%), no greater than 0.01% of sulfur (S) (exclusive of 0%), 0.002-0.040% of aluminum (Al), 0.005-0.040% of titanium (Ti), 0.0003-0.020% of zirconium (Zr), 0.0003-0.020% of rare earth metal (REM), 0.0003-0.0080% of calcium (Ca), 0.0030-0.010% of nitrogen (N), and 0.0003-0.0050% of oxygen (O), with a remainder comprising iron and unavoidable impurities.
  • C Carbon
  • the present steel material contains complex oxides containing REM, Zr, Ti, Al, Ca, and S
  • the complex oxide in the steel material has no greater than 5.0/mm 2 of oxides having a circular-equivalent diameter of greater than 3 ⁇ m, and with respect to complex oxides having a circular-equivalent diameter of 0.1-3 ⁇ m, there are at least 100/mm 2 of complex oxides satisfying formula (1). 0.008 ⁇ 1 / d ⁇ mass % S / mass % CaO + mass % REM 2 ⁇ O 3 ⁇ 0.289 (where d is the circular ⁇ equivalent diameter of each complex oxide, and is 0.1- ⁇ 3 ⁇ m).
  • the average composition of the complex oxides that are 0.1-3 ⁇ m satisfying formula (1) contains 20% or less of Al 2 O 3 , 3-20% of TiO 2 , 5-50% of ZrO 2 , 5-50% of REM, 5-50% of Cao, and 1-15% of S.
  • C is an element indispensable for securing the strength of a steel material (base plate). Accordingly, C is added in an amount of no less than 0.02%, and preferably no less than 0.04%. However, if the content of C exceeds 0.13%, many island martensites (MA) are produced in a HAZ, which leads to a decrease in HAZ toughness, and also adversely affects weldability due to the generation of CO gas, etc. Accordingly, the content of C is made no greater than 0.13%, and preferably no greater than 0.1%.
  • Si is an element having a deacidification action and also contributing to an improvement in the strength of a base plate by solute strengthening. Accordingly, Si is added in an amount of no less than 0.05%, preferably no less than 0.07%, and more preferably no less than 0.1%. However, if the content of Si exceeds 0.5%, the weldability and the toughness of a steel material are decreased, and hence the upper limit of the content thereof is made 0.5%. In order to particularly improve HAZ toughness, it is recommended that the content of Si is made no greater than 0.3%. HAZ toughness is further improved as the content of Si is smaller; however, the strength of a steel material may be conversely decreased. Accordingly, the content of Si is made no greater than 0.5%, preferably no greater than 0.35%, and more preferably no greater than 0.25%.
  • Mn is an element contributing to an improvement in the strength of a base plate. However, if the content of Mn is less than 1.0%, the strength is decreased. Accordingly, Mn is added in an amount of no less than 1.0%, and preferably no less than 1.3%. However, if the content of Mn exceeds 2.5%, the weldability of a base plate is decreased. Accordingly, the content of Mn is made no greater than 2.5%, and preferably no greater than 2.0%.
  • P is an element likely to segregate, and is an element that segregates particularly in crystal grain boundaries in a steel material such that HAZ toughness is decreased. Because P is normally and unavoidably contained in a base plate in an amount of approximately 0.001%, the content of P is specified to be no greater than 0.03%. The content of P is made preferably no greater than 0.02%, and more preferably 0.01%. In the present embodiment, however, the content of P is not inclusive of 0%.
  • S is an element that produces a sulfide (MnS) by bonding with Mn, thereby decreasing the toughness or the ductility in the through-thickness of a base plate.
  • MnS sulfide
  • S is normally and unavoidably contained in a base plate in an amount of approximately 0.0005%, and hence the content of S is specified to be no greater than 0.01%.
  • the content of S is preferably no greater than 0.008%, and more preferably no greater than 0.006%. In the present embodiment, however, the content of S is not inclusive of 0%.
  • Al is an element acting as a deoxidizing agent. If the content of Al is small, molten steel is likely to be contaminated with oxygen. Accordingly, Al is added in an amount of no less than 0.002%, preferably no less than 0.004%, and more preferably no less than 0.005%. However, if Al is added to a base plate in an excessive amount, the added Al produces coarse Al oxides by reducing the oxides in the base plate, thereby decreasing HAZ toughness. Accordingly, the content of Al is made no greater than 0.040%, preferably no greater than 0.025%, and more preferably no greater than 0.015%.
  • Ti is an element contributing to an improvement in HAZ toughness by producing, in a base plate, nitrides, such as TiN, and oxides containing Ti. Accordingly, Al is added in an amount of no less than 0.005%, preferably no less than 0.010%, and more preferably no less than 0.014%. However, if Ti is added to a base plate in an excessive amount, the base plate itself is hardened by the solute strengthening of Ti, which leads to a decrease in HAZ toughness. Accordingly, the content of Ti is made no greater than 0.040%, preferably no greater than 0.030%, and more preferably no greater than 0.025%.
  • Zr is an element contributing to an improvement in HAZ toughness by producing complex oxides containing Zr. Accordingly, Zr is added in an amount of no less than 0.0003%, preferably no less than 0.0005%, and more preferably no less than 0.0009%. However, if Zr is added to a base plate in an excessive amount, coarse Zr oxides (ZrO 2 ) are produced, thereby decreasing HAZ toughness. Further, the toughness of the base plate itself is decreased with coarse Zr carbides (ZrC) being produced. Accordingly, the content of Zr is made no greater than 0.020%, preferably no greater than 0.015%, and more preferably no greater than 0.010%.
  • REM is an element necessary for producing oxides. Oxides including the oxides produced by REM are likely to be finely dispersed in a steel material. These finely dispersed oxides serve as product nuclei of intergranular ⁇ in a HAZ, which contributes to an improvement in HAZ toughness. Accordingly, REM is added in an amount of no less than 0.0003%, preferably no less than 0.0005%, and more preferably no less than 0.0009%. However, if REM is added in an excessive amount, solid solution REM is produced and segregate in a base plate, thereby deteriorating the toughness of the base plate itself. Accordingly, the content of REM is made no greater than 0.020%, preferably no greater than 0.015%, and more preferably no greater than 0.010%.
  • the REM means elements including lanthanoid elements (15 elements ranging from La to Ln), Sc (scandium), and Y (yttrium).
  • lanthanoid elements (15 elements ranging from La to Ln), Sc (scandium), and Y (yttrium).
  • Ca is an element necessary for producing an oxide. Because Ca also serves as a product nucleus of intergranular ⁇ in a HAZ and contributes to an improvement in HAZ toughness, it is better to contain Ca in an amount of no less than 0.0003%, preferably no less than 0.0005%, and more preferably no less than 0.0007%. However, if Ca is added in an excessive amount, coarse Ca sulfides are produced, thereby deteriorating the toughness of a base plate. Accordingly, the content of Ca is made no greater than 0.0080%, preferably no greater than 0.0060%, and more preferably no greater than 0.0030%.
  • N is an element that precipitates nitrides (e.g., ZrN, TiN, etc.).
  • a nitride contributes to an improvement in HAZ toughness by suppressing the coarsening of an austenite particle, which may occur while welding is being performed, by a pinning effect. Because N further promotes an austenite particle to be made fine by forming nitrides as the content of N is larger, N effectively acts to improve HAZ toughness.
  • Al is added in an amount of no less than 0.0030%, preferably no less than 0.0040%, and more preferably no less than 0.0050%.
  • the content of N exceeds 0.010%, the amount of solid solution N is increased, thereby deteriorating the toughness of a base plate itself and also HAZ toughness. Accordingly, the content of N is made no greater than 0.010%, preferably no greater than 0.0090%, and more preferably no greater than 0.0080%.
  • O is an element indispensable for producing an oxide, and if the content thereof is less than 0.0003%, a sufficient amount of oxides cannot be obtained in a base plate.
  • the content thereof is preferably no less than 0.0010%, and more preferably no less than 0.0015%. However, if the content thereof is greater than 0.0050%, HAZ toughness is decreased due to the coarsening of oxides. Accordingly, the content of O is made no greater than 0.0050%, preferably no greater than 0.0040%, and more preferably no greater than 0.0035%.
  • the content of O refers to the amount of total oxygen, which means the total amount of O that forms oxides in a base plate and free O in the form of a solid solution in the base plate.
  • the present steel material contains the aforementioned each element, and a remainder comprises iron and unavoidable impurities.
  • the components of the remainder other than the aforementioned each element are iron and unavoidable impurities (e.g., Mg, As, Se, etc.).
  • the present steel material containing the aforementioned elements contains complex oxides (oxides and/or oxysulfides) containing REM, Zr, Ti, Al, Ca, and S.
  • the complex oxide included in the present steel material is an Al-Ti-Zr-REM-Ca-S-based complex oxide containing both oxides of Al, Ti, Zr, REM, and Ca and sulfides; however, the complex oxide may contain, other than these, elements such as, for example, Mn and Si, and other component elements.
  • An Al-Ti-Zr-REM-Ca-based oxide has a good lattice matching performance with a steel material and promotes inter-granular structure transformation (intra-granular transformation) in a HAZ, and hence the oxide is effective in causing the structure of a HAZ to be made fine.
  • the number of oxides having a circular-equivalent diameter of greater than 3 ⁇ m is no greater than 5.0/mm 2 in the cross section of the steel material. Because a complex oxide having a circular-equivalent diameter of greater than 3 ⁇ m is coarse, the complex oxide conversely decreases HAZ toughness for high heat input welding whose heat input almost reaches 60 kJ/mm. Accordingly, the number of complex oxides having a size of greater than 3 ⁇ m should be made no greater than 5.0/mm 2 .
  • the present steel material contains the aforementioned complex oxides such that, with respect to complex oxides having a circular-equivalent diameter of no less than 0.1 ⁇ m and no greater than 3 ⁇ m (hereinafter, expressed by 0.1-3 ⁇ m) and satisfying formula (1), there are at least 100/mm 2 in the cross section of the steel material. 0.008 ⁇ 1 / d ⁇ mass % S / mass % CaO + mass % REM 2 ⁇ O 3 ⁇ 0.289 (where d is the circular ⁇ equivalent diameter of each complex oxide, and is 0.1-3 ⁇ m).
  • This complex oxide having a circular-equivalent diameter of 0.1-3 ⁇ m promotes intra-granular structure transformation (intra-granular transformation) in a HAZ and improves HAZ toughness, and hence a complex oxide having a circular-equivalent diameter of 0.1-3 ⁇ m will be examined below.
  • a complex oxide having a circular-equivalent diameter of less than 0.1 ⁇ m hardly contributes to an improvement in HAZ toughness, and hence it is not included in the number of the aforementioned complex oxides.
  • REM and Ca are oxysulfide forming elements that can form both an oxide and a sulfide. So, if an S concentration (mass% S) to the concentrations of oxysulfide forming elements (REM 2 O 3 and CaO) is too high, excessively produced sulfides hamper the matching between oxides and the matrix, and hence an ability (intra-granular transformation ability), in which a complex oxide contributes to structure control, is decreased.
  • the second term is shown, in which these conditions under which intra-granular transformation is believed to be affected are taken into consideration.
  • the second term of formula (1) there are optimal ranges both in an S concentration (mass% S) to the concentrations of oxysulfide forming elements (REM 2 O 3 and CaO) and in the size of a complex oxide (circular-equivalent diameter d of a complex oxide), for generating the strain energy contributing to intra-granular transformation; and it is inferred that an upper limit and a lower limit may exist in the second term of formula (1). So, the upper limit and the lower limit of the second term of formula (1) were experimentally determined.
  • a method for determining the upper limit and the lower limit of the second term of formula (1) will be described.
  • a heat input test which simulated a HAZ in welding whose heat input was 60 kJ/mm, was first performed on a test material. Thereafter, the test material having subjected to the heat input test was subjected to mirror polishing such that corrosion progressed, and the presence/absence of intra-granular transformation resulting from a complex oxide was examined by revealing the structure with the corrosion. Subsequently, the composition and the size of a complex oxide in the test material were measured by an EPMA (Electron Probe MicroAnalyzer), so that the value of the second term of formula (1) was calculated with respect to a complex oxide having a size of 0.1-3 ⁇ m.
  • EPMA Electro Probe MicroAnalyzer
  • complex oxides having a circular-equivalent diameter of 0.1-3 ⁇ m and satisfying formula (1) there are at least 100/mm 2 contained, and furthermore the average composition thereof should contain no greater than 20% of Al 2 O 3 , no less than 3% and no greater than 20% (3-20%) of TiO 2 , no less than 5% and no greater than 50% (5-50%) of ZrO 2 , no less than 5% and no greater than 50% (5-50%) of REM oxide, no less than 5% and no greater than 50% (5-50%) of CaO, and no less than 1% and no greater than 15% (1-15%) of S.
  • oxide compositions affect the lattice matching performance between an oxide and a steel material in a HAZ, and hence if the oxide compositions are not controlled such that the contents thereof fall within the aforementioned ranges, a complex oxide having a circular-equivalent diameter of 0.1-3 ⁇ m cannot contribute to the intra-granular transformation in a HAZ, that is, cannot contribute to making a HAZ structure fine.
  • the present steel material having the aforementioned chemical component composition targets a thick steel plate having a thickness of approximately no less than 3.0 mm, and a decrease in HAZ toughness can be prevented for small to middle heat input welding and even for high heat input welding whose heat input is no less than 50 kJ/mm; and accordingly the steel material can be used as a material for large structures such as, for example, brides, high-rise buildings, and ships.
  • the steel material according to the present embodiment may contain at least one of Ni, Cu, Cr, and Mo in an amount of no less than 0.05% and no greater than 1.50% (0.05-1.50%).
  • Ni, Cu, Cr, and Mo is an element contributing to increases in the toughness and strength of the present steel material, and each of them can be added alone or in combination thereof.
  • the content of Cu exceeds 1.50%, the strength of a base plate becomes too large and the toughness of the base plate is conversely decreased, and hence HAZ toughness is also decreased. Accordingly, the content of Cu is specified to be no less than 0.05% and no greater than 1.50%.
  • Ni, Cr, or Mo in an amount of no less than 0.05%, similarly to Cu; however, if the content thereof exceeds 1.50%, the strength of a base plate becomes too large and the toughness of the base plate is conversely decreased, and hence HAZ toughness is also decreased. Accordingly, the content of Ni, Cr, or Mo is also specified to be no less than 0.05% and no greater than 1.50%.
  • the steel material according to the present embodiment may further contain at least one of Nb and V in an amount of no less than 0.002% and no greater than 0.10% (0.002-0.10%).
  • Nb and V precipitates as a carbonitride. Because this carbonitride exerts a pinning effect, the coarsening of an austenite particle is suppressed while welding is being performed, thereby contributing to an improvement in HAZ toughness. So, in order to effectively improve HAZ toughness by adding Nb, it is preferable to contain Nb in an amount of no less than 0.002%. However, if the content of Nb exceeds 0.10%, the precipitating carbonitride is coarsened, which conversely decreases HAZ toughness. Accordingly, the content of Nb is specified to be no less than 0.002% and no greater than 0.10%.
  • V in an amount of no less than 0.002%, similarly to Nb. However, if the content of V exceeds 0.10%, the precipitating carbonitride is coarsened, which conversely decreases HAZ toughness. Accordingly, the content of V is specified to be no less than 0.002% and no greater than 0.10%.
  • the steel material according to the present embodiment may additionally contain B in an amount of no less than 0.0005% and no greater than 0.0050% (0.0005-0.0050%).
  • B is an element that improves toughness by suppressing the production of grain boundary ferrite. So, in order to improve the toughness of the present steel material by adding B, it is preferable to contain B in an amount of no less than 0.0005%. It is more preferable to contain B in an amount of no less than 0.0010%, and still more preferable to contain B in an amount of no less than 0.0015%. However, if the content of B exceeds 0.0050%, B precipitates as BN in an austenite grain boundary, which leads to a decrease in toughness. Accordingly, the content of B is made no greater than 0.0050%, preferably no greater than 0.0040%, and more preferably no less than 0.0015% and no greater than 0.0030%.
  • the steel material according to the present embodiment can be obtained by adding, for example, in the second refining of molten steel, each element so as to have the aforementioned chemical component composition, and a production method (production conditions) of the steel shown in the later-described examples, namely, a method of adding each element will be described as one example of a production method of the present steel material.
  • the steel shown in the later-described Examples and Comparative Examples were obtained by melting steel with the use of a vacuum melting furnace (capacity: 150 kg) and then by casting into a 150-kg ingot that is then cooled.
  • a dissolved oxygen amount and an S concentration in molten steel melted in the vacuum melting furnace were first adjusted.
  • the dissolved oxygen amount (mass% Of) before the addition of complex oxide forming elements was first adjusted to be no greater than 0.005%.
  • the S concentration (mass% S) in the molten steel was adjusted such that the ratio (mass% Of/mass% S) of the dissolved oxygen concentration (mass% Of) to the S concentration (mass% S) was 0.2 ⁇ mass% Of/mass% S ⁇ 9.6.
  • a desulfurization method for adjusting the S concentration is not particularly limited, but molten steel having a low S concentration in advance may be used.
  • the bases of the aforementioned dissolved oxygen amount and S concentration are as follows. If a dissolved oxygen amount exceeds 0.005%, the oxide produced in molten steel is first coarsened. Furthermore, if the value of (mass% Of/mass% S) is large, sulfides that are necessary for oxides are not fully produced. Alternatively, if the value of (mass% Of/mass% S) is small, not only desired oxides cannot be obtained, but also sulfides are produced to a level at which intra-granular transformation is hampered because the S concentration is too high.
  • Al which is one of oxysulfide forming elements, was added to the molten steel ahead of Ti.
  • Ti was added to the molten steel ahead of REM and Zr. If Ti is added ahead of Al, all of the Ti oxides are reduced by Al in the subsequent steps, and hence Ti should be added after the addition of Al. After the addition of Ti, the molten steel was retained for no shorter than 2 minutes and no longer than 15 minutes without the addition of other elements.
  • REM and Zr were added.
  • the order of the addition of REM and Zr is not particularly limited. That is, they may be added in the order of REM and Zr, or Zr and REM, or may be added at the same time.
  • REM has the characteristic of easily forming both oxides and sulfides
  • Zr has the characteristic of forming oxides but not forming sulfides. Accordingly, in order to make the balance between oxides and sulfides proper, it is necessary to add Zr and REM in accordance with the mass% Of and mass% S. So, the ratio of the addition amount of Zr and that of REM (add [Zr]/add [REM]) is determined to satisfy the following formula (2).
  • Ca After the addition of REM and Zr, Ca was added and the molten steel was cast. Ca also forms an oxide and a sulfide, but the forms of the oxide and the sulfide are basically dependent on the forms of the inclusions already present in molten steel, and hence the forms of the inclusions, before the addition of Ca, should be particularly noted.
  • the forms of REM, Ca, Zr, and Ti, which are to be added to the molten steel are not particularly limited, and, for example, pure La, pure Ce, or pure Y, as REM; pure Ca, pure Zr, or pure Ti; or further an Fe-Si-La alloy, Fe-Si-Ce alloy, Fe-Si-Ca alloy, Fe-Si-La-Ce alloy, Fe-Ca alloy, or Ni-Ca alloy; or the like, may be added.
  • a misch metal may be added to the molten steel.
  • the misch metal is a mixture of rare earth elements, and specifically it contains approximately 40-50% of Ce and approximately 20-40% of La.
  • a misch metal often contains Ca as an impurity, and hence when a misch metal contains Ca, the range of Ca content specified in the present embodiment should be satisfied.
  • compositions (contents) of the component elements are referred to as "conditions specified in the present embodiment".
  • the molten steel whose components were adjusted as described above was cast into an ingot.
  • the cast ingot was hot-rolled and processed such that a thick steel plate having a thickness of 30-80 mm was produced.
  • it is sufficient that the molten steel obtained with its components being adjusted is processed into a slab by continuous casting according to a normal method and then hot-rolled according to a normal method.
  • a test piece for a welded joint was taken from the thick steel plate and was subjected to V-beveling processing, and electrogas arc welding whose heat input was 60 kJ/mm, equivalent to high heat input welding, was then performed.
  • Three test pieces for Charpy impact test (V-notched test pieces according to JIS Z 2202) were taken, in which a HAZ, located near to a weld line (bond) positioned at a depth of t/4 (t: thickness of the test piece) from the surface of the welded test piece, was processed to have a notch.
  • a Charpy impact test was performed at -40°C on each of the three V-notched test pieces to measure absorbed energy (vE-40), so that the average value and the minimum of the measurement results of the three V-notched test pieces were determined.
  • test piece thin steel plate having an average value of vE-40 of greater than 140 J was evaluated as a steel plate having superior HAZ toughness.
  • test piece was cut out from a position at a depth of t/4 (t: thickness of the thick steel plate) from the surface of the thick steel plate (the test piece was taken such that the shaft center thereof passed through the position at a depth of t/4), and a cross section parallel to the rolling direction and the thickness direction was subjected to mirror polishing; and with respect to this test piece, the composition of a complex oxide having a size of 0.1-3 ⁇ m was measured by using an EPMA (Electron Probe X-ray Microanalyzer made by JEOL Datum (product name: JXA-8500F)).
  • EPMA Electro Probe X-ray Microanalyzer made by JEOL Datum (product name: JXA-8500F)
  • Observation conditions in this case were set such that an acceleration voltage was 20 kV, a sample current was 0.01 ⁇ A, a magnification was 5000 times, and an observation area was no less than 0.4 mm 2 , and the component composition at the center of the complex oxide was quantitatively analyzed by wavelength dispersive spectroscopy of characteristic X-rays.
  • the elements to be the targets of the quantitative determination were set to be Si, Mn, S, Al, Ti, Zr, La, Ce, Ca, and O (oxygen), and the relationship between the X-ray intensity of each element and the concentration of the each element was determined, in advance, as a calibration curve by using a known substance, so that the amount of an element contained in a complex oxide that was an analysis target was quantitatively determined based on the X-ray intensity and the calibration curve obtained from the complex oxide.
  • Each of the aforementioned elements other than S was converted into a simple oxide, so that the composition of the oxide was calculated from the ratio of the X-ray intensity that showed the existence of the each element.
  • the concentration of S was calculated as being present alone.
  • the composition of a complex oxide was determined with mass conversion assuming that there were simple oxides and S present alone, as described above, and an average composition of a plurality of complex oxides was determined as the composition of the complex oxide.
  • the oxides of REM exist in the forms of M 2 O 3 , M 3 O 5 , and MO 2 , etc., in the steel material; however, all of the oxides thereof were converted into M 2 O 3 . Similarly, all of the oxides of Ti were converted into TiO 2 .
  • the area of the complex oxide was measured, and the diameter of a circle corresponding to the measured area was calculated as a circular-equivalent diameter, assuming that the shape of the complex oxide was a circle.
  • observation conditions were set such that a magnification was 200 times, an observation area was no less than 50 mm 2 , and the conditions other than these were the same as those under which the number of complex oxides having a circular-equivalent diameter of no greater than 5 ⁇ m was measured.
  • Table 2 shows the chemical component compositions of steel materials Nos. 1-31 that are examples of the steel material according to the embodiment. All of the component compositions of the steel materials Nos. 1-31 satisfy the conditions specified in the embodiment.
  • Table 3 shows the production conditions of the steel materials Nos. 1-31 that are examples of the present steel material. All of the production conditions of the steel materials Nos. 1-31 also satisfy the conditions specified in the present embodiment. When there are multiple orders or methods, etc., of adding component elements, the selected addition order or addition method is shown in the remarks column. [Table 3] No.
  • Table 4 shows test results for the particle sizes, the piece-number distributions, and the average compositions of complex oxides, and for the HAZ toughness of the steel materials Nos. 1-31 that are examples of the present steel material.
  • the number of complex oxides having a circular-equivalent diameter of greater than 3 ⁇ m is no greater than 5.0/mm 2
  • the number of complex oxides having a circular-equivalent diameter of 0.1-3 ⁇ m is at least 100 /mm 2 .
  • the average composition of complex oxides having a circular-equivalent diameter of 1-3 ⁇ m satisfies the conditions specified in the present embodiment.
  • each of the steel materials Nos. 1-31 has HAZ toughness of no less than 140 J, and hence it can be evaluated as exerting superior HAZ toughness.
  • Table 5 shows the component compositions of steel materials Nos. 32-67 that are examples in which the conditions specified in the present embodiment are not satisfied.
  • the content of Al does not satisfy the condition specified in the embodiment.
  • the contents of Ti do not satisfy the condition specified in the embodiment.
  • the contents of REM do not satisfy the condition specified in the embodiment.
  • the contents of Zr do not satisfy the condition specified in the embodiment.
  • the contents of Ca do not satisfy the condition specified in the embodiment.
  • the contents of S do not satisfy the condition specified in the embodiment.
  • the other steel materials satisfy the aforementioned component compositions.
  • Table 6 shows the production conditions of the steel materials Nos. 32-67 that do not satisfy the conditions specified in the present embodiment.
  • an "x" mark is provided in the "addition order of complex oxide forming elements", which indicates that the complex oxide forming elements (Al and Ti) were added in an order different from the aforementioned one.
  • a holding time after the addition of Ti does not satisfy the condition specified in the embodiment.
  • the value of (mass% Of/mass% S) does not satisfy the condition specified in the embodiment.
  • Table 7 shows test results for the particle sizes, the piece-number distributions, and the average compositions of complex oxides, and for the HAZ toughness of the steel materials Nos. 32-67 as comparative examples in which the conditions specified in the present embodiment are not satisfied.
  • the average composition of a complex product does not satisfy the condition specified in the embodiment.
  • the number of complex oxides having a circular-equivalent diameter of greater than 3 ⁇ m exceeds 5.0/mm 2 .
  • the test result for HAZ toughness was less than 140 J, namely, in a comparative example in which one or more of the conditions specified in the embodiment were not satisfied, a steel material having superior HAZ toughness was not able to be obtained.
  • Fig. 1 is a graph showing the HAZ toughness of the steel materials according to the embodiment shown in Table 4 and those of the steel materials Nos. 59 and 61-67 of the comparative examples shown in Table 7.
  • the number of complex oxides having a circular-equivalent diameter of greater than 3 ⁇ m is less than 5.0/mm 2 ; however, each of the steel materials Nos.
  • 59 and 61-67 of the comparative examples represents an example in which the number of complex oxides having a circular-equivalent diameter of 0.1-3 ⁇ m was less than 100, and the test result for the HAZ toughness of each of them was greatly less than 140 J.
  • Fig. 2 is a graph showing the HAZ toughness of the steel materials according to the present embodiment shown in Table 4 and those of the steel materials Nos. 32-55 of the comparative examples shown in Table 7.
  • the number of complex oxides having a circular-equivalent diameter of greater than 3 ⁇ m is less than 5.0/mm 2 and the number of complex oxides having a circular-equivalent diameter of 0.1-3 ⁇ m is at least 100; however, each of the steel materials Nos. 32-55 of the comparative examples represents an example in which the average composition of a complex oxide does not satisfy the conditions specified in the embodiment, and the test result for HAZ toughness of each of them was greatly less than 140 J.
  • Fig. 3 is a graph showing the HAZ toughness of the steel materials according to the present embodiment shown in Table 4 and those of the steel materials Nos. 56 and 57 of the comparative examples shown in Table 7.
  • the number of complex oxides having a circular-equivalent diameter of 0.1-3 ⁇ m is at least 100; however, each of the steel materials Nos. 56 and 57 of the comparative examples represents an example in which the number of complex oxides having a circular-equivalent diameter of greater than 3 ⁇ m is no less than 5.0/mm 2 , and the test result for the HAZ toughness of each of them was greatly less than 140 J.
  • a steel material having a structure that satisfies the conditions specified in the present embodiment, can exert superior HAZ toughness even for high heat input welding.
  • the embodiments disclosed herein are to be construed as being exemplary in all respects and not to be construed as being limitative.
  • the matters explicitly disclosed herein such as, for example, running conditions, operating conditions, various parameters, and the size, weight, or volume of a structure, are not deviated from the ranges within which a person skilled in the art usually performs, and the values that a usual person skilled in the art can easily conceive of are adopted.
  • the present steel material is produced in secondary refining; however, a steel material having similar HAZ toughness can be produced by using, for example, a converter furnace or an electric furnace. Accordingly, a production method of the present steel material using a converter furnace or an electric furnace is also encompassed by the technical scope of the present invention.
  • a steel plate according to the present invention achieves superior HAZ toughness even for high heat input welding, and hence is suitable to be used in welded structures, such as ships, constructions, and bridges.

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EP3418412A4 (fr) * 2016-02-19 2019-08-21 Nippon Steel Corporation Acier
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JP7328491B2 (ja) * 2018-11-09 2023-08-17 日本製鉄株式会社 無方向性電磁鋼板
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CN114086069B (zh) * 2021-03-04 2022-05-20 东北大学 一种含镁细晶粒热轧板带钢及其制备方法
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Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11264048A (ja) 1998-03-16 1999-09-28 Nippon Steel Corp 溶接部靱性の優れた高強度鋼板
JP4144121B2 (ja) 1999-07-06 2008-09-03 Ｊｆｅスチール株式会社 母材および溶接熱影響部の靱性に優れた非調質高張力鋼材
JP4762450B2 (ja) 2001-08-06 2011-08-31 新日本製鐵株式会社 母材靭性と溶接部ｈａｚ靭性に優れた高強度溶接構造用鋼の製造方法
JP4039223B2 (ja) 2002-01-22 2008-01-30 Ｊｆｅスチール株式会社 超大入熱溶接熱影響部靭性に優れた厚鋼板およびその製造方法
JP4261968B2 (ja) 2003-04-24 2009-05-13 新日本製鐵株式会社 溶接熱影響部靭性の優れた鋼材およびその製造方法
JP4515428B2 (ja) * 2006-09-29 2010-07-28 株式会社神戸製鋼所 溶接熱影響部の靭性および脆性破壊発生特性に優れた鋼材およびその製法
JP5201665B2 (ja) * 2007-11-13 2013-06-05 株式会社神戸製鋼所 大入熱溶接時の熱影響部の靭性に優れた溶接用高張力厚鋼板
JP2009179844A (ja) * 2008-01-30 2009-08-13 Kobe Steel Ltd 溶接熱影響部の靭性に優れた高張力厚鋼板
JP5231042B2 (ja) * 2008-02-20 2013-07-10 株式会社神戸製鋼所 溶接熱影響部の靭性に優れた鋼材およびその製造方法
JP5342902B2 (ja) * 2009-03-11 2013-11-13 株式会社神戸製鋼所 溶接熱影響部の靭性および母材疲労特性に優れた鋼材およびその製造方法
JP5520105B2 (ja) * 2009-07-15 2014-06-11 株式会社神戸製鋼所 溶接熱影響部の靱性に優れた鋼材およびその製造方法
JP2011127220A (ja) 2009-11-18 2011-06-30 Kobe Steel Ltd 溶接熱影響部の靱性に優れた鋼材の製造方法
JP5444093B2 (ja) * 2010-04-07 2014-03-19 株式会社神戸製鋼所 溶接熱影響部の靭性に優れた厚鋼板
JP5651090B2 (ja) * 2011-01-18 2015-01-07 株式会社神戸製鋼所 溶接熱影響部の靱性に優れた鋼材およびその製造方法
JP5158272B2 (ja) * 2011-03-10 2013-03-06 新日鐵住金株式会社 伸びフランジ性と曲げ加工性に優れた高強度鋼板およびその溶鋼の溶製方法

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3418412A4 (fr) * 2016-02-19 2019-08-21 Nippon Steel Corporation Acier
EP3418411A4 (fr) * 2016-02-19 2019-08-21 Nippon Steel Corporation Acier
US20200165711A1 (en) * 2016-02-19 2020-05-28 Nippon Steel & Sumitomo Metal Corporation Steel

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EP2977479A4 (fr) 2016-11-30
JP6226542B2 (ja) 2017-11-08
CN105051229B (zh) 2017-03-15
EP2977479B1 (fr) 2018-04-25
WO2014148447A1 (fr) 2014-09-25
CN105051229A (zh) 2015-11-11

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