WO2017111443A1 - 열간 저항성이 우수한 고강도 구조용 강판 및 그 제조방법 - Google Patents
열간 저항성이 우수한 고강도 구조용 강판 및 그 제조방법 Download PDFInfo
- Publication number
- WO2017111443A1 WO2017111443A1 PCT/KR2016/014964 KR2016014964W WO2017111443A1 WO 2017111443 A1 WO2017111443 A1 WO 2017111443A1 KR 2016014964 W KR2016014964 W KR 2016014964W WO 2017111443 A1 WO2017111443 A1 WO 2017111443A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- steel sheet
- less
- strength
- structural steel
- hot resistance
- Prior art date
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/16—Ferrous alloys, e.g. steel alloys containing copper
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—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
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—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
- C22C38/08—Ferrous alloys, e.g. steel alloys containing nickel
-
- 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
- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/004—Dispersions; Precipitations
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/005—Ferrite
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
Definitions
- the present invention relates to a high strength structural steel sheet excellent in hot resistance and a method of manufacturing the same.
- the exterior of ships, marine and building structures has a structure in which both planes and surfaces exist at the same time.
- the processing for the plane is determined at the time of forming the plate, the exterior is formed without additional process when drying ships and offshore structures, but during the forming of the surface, the plate is processed to heat the surface of the steel sheet.
- the onboard heating which is a task to be performed, is performed.
- Bending processing by linear heating utilizes the property of being deformed by restraint from the surrounding unheated area when it contracts by cooling after thermal expansion of the heating part.
- the surface of the steel sheet may be heated to a temperature of about 600 to 900 ° C. or by water cooling after heating, so that the physical properties of the steel sheet after linear heating may be inferior.
- the heating up to the austenite starting transformation temperature of the steel mainly causes material deterioration due to growth of crystal grains when heated above the transformation temperature or the recrystallization temperature due to dislocation dislocation or the like.
- the present invention is to provide a high-strength structural steel sheet excellent in yield resistance, tensile strength and impact toughness even after linear heating, and a manufacturing method thereof.
- One aspect of the present invention is by weight, C: 0.03 to 0.07%, Si: 0.05 to 0.2%, Mn: 1.6 to 2.3%, P: 0.008% or less, S: 0.002% or less, Al: 0.025% or less, Cu : 0.1 to 0.4%, Ni: 1.4 to 2.3%, Mo: 0.08 to 0.2%, Nb: 0.01 to 0.025%, Ti: 0.008 to 0.02%, N: 0.001 to 0.008%, remaining Fe and inevitable impurities,
- the microstructure within 10mm of the surface is to provide a high-strength structural steel sheet having excellent hot resistance, including needle-like ferrite of 80% or more and polygonal ferrite of 20% or less by volume fraction.
- C 0.03 ⁇ 0.07%
- Si 0.05 ⁇ 0.2%
- Mn 1.6 ⁇ 2.3%
- P 0.008% or less
- S 0.002% or less
- Al 0.025% or less
- Cu 0.1 to 0.4%
- Ni 1.4 to 2.3%
- Mo 0.08 to 0.2%
- Nb 0.01 to 0.025%
- Ti 0.008 to 0.02%
- N 0.001 to 0.008%
- remaining Fe and inevitable impurities Reheating the slab
- the present invention it is possible to provide a high strength structural steel sheet having excellent yield strength, tensile strength and low temperature impact toughness, and a method for manufacturing the same, as well as hot resistance before the linear heating, and even after the linear heating.
- FIG. 1 is a schematic diagram showing an example of curved surface forming by linear heating.
- FIG. 2 is a cross-sectional photograph of a 10 mm depth from the surface of the steel sheet of Inventive Example 1.
- the inventors have found that the physical properties of the steel sheet may be inferior after the linear heating when the high strength structural steel sheet is subjected to linear heating so that the exterior of ships, marine and building structures have curved surfaces.
- This linear heating causes the surface of the steel sheet to be heated to 600 to 900 ° C., resulting in a decrease in strength and toughness simultaneously due to softening of the matrix structure and grain boundaries, grain growth, coarsening of carbide (Fe 3 C), and the like.
- the heating up to the austenite start transformation temperature is caused to deteriorate the material due to the dislocation of the dislocation, and when the heating is more than the transformation temperature or more than the recrystallization temperature, mainly due to the growth of grains, the material is mainly degraded.
- the present inventors lowered the Ar3 temperature by the addition of high Mn and Ni, so that the microstructure within 10 mm of the surface by the low temperature rolling and the cold cooling, the acicular ferrite of 80% or more and the polygonal ferrite of 20% or less.
- the present invention has been completed by realizing that it is possible to provide a high strength structural steel sheet having excellent yield strength, tensile strength and low-temperature impact toughness even after linear heating, and a method of manufacturing the same.
- High-strength structural steel sheet having excellent hot resistance according to an aspect of the present invention by weight%, C: 0.03 ⁇ 0.07%, Si: 0.05 ⁇ 0.2%, Mn: 1.6 ⁇ 2.3%, P: 0.008% or less, S: 0.002% Al: 0.025% or less, Cu: 0.1 to 0.4%, Ni: 1.4 to 2.3%, Mo: 0.08 to 0.2%, Nb: 0.01 to 0.025%, Ti: 0.008 to 0.02%, N: 0.001 to 0.008%, It contains the remaining Fe and unavoidable impurities, and the microstructure within 10 mm of the surface contains 90% or more of needle-like ferrite.
- C is a very important element for securing strength.
- the upper limit is preferably 0.07%.
- Si is a useful element as a deoxidizer, but if its content is excessive, it may cause a decrease in toughness.
- the Si content is preferably 0.05% or more, and when the Si content exceeds 0.2%, the toughness may be lowered. Therefore, it is preferable that Si content is 0.05 to 0.2%.
- Mn is a solid solution strengthening element and has the effect of improving the strength, grain refinement and base material toughness.
- Ar3 temperature it is possible to minimize the formation of polygonal ferrite by low temperature rolling and cold cooling.
- the upper limit is 2.3%.
- P is an element that is advantageous in improving strength and corrosion resistance, it is advantageous to keep it as low as possible because it is an element that greatly impairs impact toughness. Therefore, the upper limit thereof is preferably 0.008%.
- the upper limit is preferably made 0.002%.
- Al is an element which can effectively deoxidize, and it is preferable to control it to 0.005 to 0.025%. It is not necessary to specifically control the lower limit, but may be included 0.005% or more for deoxidation.
- Cu is a solid solution strengthening and precipitation strengthening element that can improve the strength while minimizing the toughness of the base metal.
- it is preferable to contain 0.1% or more.
- the upper limit is preferably 0.4% or less.
- Ni is an element which can improve the strength and toughness of a base material simultaneously.
- Ar3 temperature it is possible to minimize the formation of polygonal ferrite by low temperature rolling and cold cooling.
- Ni content is less than 1.4%, the above-described effects are insufficient, and when the Ni content is more than 2.3%, the hardenability is increased, and impact toughness may be reduced due to bainite formation. Therefore, it is preferable that Ni content is 1.4-2.3%.
- Mo is an element that effectively increases the strength by the addition of a small amount, and is preferably added in an amount of 0.08% or more since the formation of fine Mo-C series precipitates after linear heating prevents deterioration of the strength.
- the upper limit is 0.2% or less because coarsening of precipitates may occur due to excessive Mo addition.
- Nb that has been dissolved in the steel sheet before the linear heating is precipitated in the form of NbC, NbCN, etc. during the linear heating to improve the strength of the base metal. This is important for maintaining strength after linear heating, and 0.01% or more should be added in order to effectively exhibit the effect of adding Nb.
- the upper limit is preferably 0.025% or less.
- Ti forms nitrides with N to prevent grains from growing at high temperatures. In order to secure such an effect sufficiently, it is preferable to be contained 0.008% or more. On the other hand, excessive Ti addition has a problem in that impact toughness is lowered due to coarsening of Ti precipitates, so the upper limit is preferably 0.02%.
- N is an element that forms a precipitate together with Ti, Nb, Al and the like to refine the austenite structure upon reheating, thereby improving strength and toughness.
- N content is less than 0.001%, the above effects cannot be sufficiently obtained.
- N content is greater than 0.008%, surface cracks may be caused at high temperatures, and residual N may exist in an atomic state to reduce toughness. Therefore, it is preferable that N content is 0.001 to 0.008%.
- the remaining component of the steel sheet of the present invention is iron (Fe).
- Fe iron
- impurities which are not intended from the raw material or the surrounding environment may be inevitably mixed, and thus cannot be excluded. Since these impurities are known to those skilled in the art, all of them are not specifically mentioned in the present specification.
- the microstructure within 10 mm of the surface of the high-strength structural steel sheet having excellent hot resistance according to an aspect of the present invention includes more than 80% acicular ferrite and less than 20% polygonal ferrite by volume fraction.
- Polygonal ferrite is easy to grain growth by heating, so if the polygonal ferrite is present in more than 20% by volume in the microstructure within 10mm, grain growth, coarse carbide formation and matrix structure during linear heating It may cause deterioration.
- the thickness of the steel sheet is preferably 40mm or less. This is because when the thickness of the steel sheet exceeds 40 mm, it is difficult to apply curved processing by linear heating. At this time, the minimum thickness of the steel sheet may be 12mm.
- the steel sheet has a yield strength of 500 MPa or more, a tensile strength of 600 MPa or more, and an impact toughness of 100 J or more at -40 ° C. Accordingly, it can be preferably used for ships, offshore and building structures.
- curved processing by linear heating (bending processing) is deformed due to restraint from the surrounding non-heating region when it contracts by cooling after thermal expansion of a heating part. Use nature.
- linear heating generally heats the surface of the steel sheet to 600-900 ° C.
- 600-800 ° C which is a relatively low temperature
- Mo dissolved in the steel sheet precipitates as Mo 2 C when cooled after the linear heating, and is relatively high.
- Nb dissolved in the steel sheet is precipitated as NbC upon cooling after linear heating.
- the Mo 2 C precipitates or NbC precipitates are precipitated at the grain boundaries to inhibit the growth of the grains (pinning effect) and to prevent the formation of coarse carbides. In addition, since C is consumed a lot as precipitates, generation and coarsening of carbides can be prevented.
- the Mo 2 C NbC precipitates, and the size of the precipitate is preferably 2 ⁇ 20nm.
- the steel sheet according to the present invention is capable of securing a yield strength of 500 MPa or more, a tensile strength of 600 MPa or more, and an impact toughness of 100 J or more at -40 ° C. even when linearly heated and curved at 600 to 900 ° C. .
- Another aspect of the present invention is a method of manufacturing a high strength structural steel sheet having excellent hot resistance, comprising: reheating a slab having the above-described alloy composition; Unrecrystallization of the reheated slab at 750 ⁇ 850 °C; And cooling down to a cooling end temperature of 380-440 ° C. at a cooling rate of 10 ° C./sec or more after unrecrystallized station rolling.
- the slab having the alloy composition described above is reheated.
- the reheating temperature of the slab is not particularly limited, but is preferably 1100 to 1200 ° C.
- the reheated slab is unrecrystallized rolled at 750 ⁇ 850 °C. This is to refine the grains.
- the unrecrystallized rolling In order to refine the grains, the unrecrystallized rolling must be performed at the lowest temperature immediately above the Ar3 temperature. In the present invention, in order to have a sufficiently low Ar3 temperature, the Mn and Ni contents are increased to have a sufficiently low Ar3 temperature. It is preferable to perform non-recrystallization rolling. In addition, when the unrecrystallized rolling temperature exceeds 850 degreeC, grain refinement
- the microstructure within 10mm from the surface of the steel sheet can be contained in the volume fraction of acicular ferrite of 80% or more and polygonal ferrite of 20% or less.
- cooling rate is less than 10 °C / sec, or the cooling end temperature exceeds 440 °C sufficient cooling is not achieved a large amount of polygonal ferrite is formed and the grain growth and matrix deterioration occurs in the linear heating.
- the step of heating the cooled steel sheet in a linear process at 600 ⁇ 900 °C can be further performed.
- Invented steels A, B, and C are steel sheets satisfying the component range defined in the present invention, and comparative steels D, F, G, and H are compared as steel sheets containing an alloy component that exceeds or falls short of the component range of the present invention.
- Steel D is carbon
- comparative steel E is Mo
- comparative steel F is Nb
- comparative steel G is the case where the components of Ni and Mn are outside the component range of this invention.
- the inventive steel and the comparative steel were rolled and cooled in the preparation conditions of Table 2 to prepare a thick steel sheet.
- the rolling finish temperature was 780 °C, 880 °C
- the cooling end temperature was carried out at 400 °C, 600 °C.
- the steel sheet was cut into a size capable of linear heating, and linear heating was performed under four temperature conditions (600 ° C, 700 ° C, 800 ° C, and 900 ° C).
- Table 3 below shows the mechanical properties and the mechanical properties after linear heating of the base material prepared under the above conditions.
- Tensile strength of the base metal was measured from the full thickness of the steel sheet in a direction perpendicular to the rolling direction, and subjected to a tensile test at room temperature to measure tensile strength.
- the low temperature toughness of the base material was taken from 2 mm directly below the surface of the steel sheet, and the specimens were taken in the direction perpendicular to the rolling direction. After the V-notched test specimens were prepared, the Charpy impact test was performed three times at -40 ° C. .
- the microstructure within 10 mm of the surface of the steel sheet was observed to show the volume fraction of polygonal ferrite in Table 3.
- the tissue other than polygonal ferrite was acicular ferrite.
- the unit of temperature is °C
- the unit of the cooling rate is °C / sec
- FM start temperature means the unrecrystallized station rolling start temperature
- FM end temperature means the unrecrystallized station rolling end temperature.
- the yield strength of 500 MPa or more, the tensile strength of 600 MPa or more, and the -40 degree impact toughness of 100 J or more were shown before and after the linear heating.
- Comparative Example 3 is a case of using the comparative steel D in which the component of C is exceeded, the strength is significantly raised to the target level, but it can be seen that the impact toughness is significantly reduced. This is because the formation of coarse carbides is a cause of breakage during the impact test.
- Comparative Example 4 is a case of using a comparative steel E that is less than the Mo component
- Comparative Example 5 is a case of using a comparative steel F is less than the Nb component, it can be seen that the strength is significantly reduced and the impact toughness is also reduced. This is because the amount of Mo and Nb employed is small and the amount of Mo and Nb insufficient to form precipitates after linear heating is insufficient. If Mo and Nb is added excessively, the toughness may be reduced due to coarse precipitates, so it should be added within the range controlled by the present invention.
- Comparative Example 6 is a case of using the comparative steel G, which is less than the components of Mn, Ni, because a sufficiently low Ar3 temperature is not secured, a large amount of polygonal ferrite is formed when rolling at low temperature, thereby reducing the strength and toughness. Caused.
- Comparative Example 1 the alloy composition of the present invention was satisfied, but the impact toughness was inferior because the rolling temperature exceeded 850 ° C.
- Comparative Example 3 the alloy composition of the present invention was satisfied, but the cooling condition was beyond the scope of the present invention, resulting in a decrease in strength and toughness due to grain growth after linear heating due to an increase in the polygonal ferrite fraction.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
- Heat Treatment Of Sheet Steel (AREA)
Abstract
Description
구분 | C | Si | Mn | P | S | Al | Ni | Cu | Mo | Nb | Ti | N |
발명강 A | 0.042 | 0.086 | 1.95 | 0.0055 | 0.0015 | 0.011 | 1.71 | 0.274 | 0.13 | 0.015 | 0.010 | 0.0038 |
발명강 B | 0.054 | 0.116 | 1.83 | 0.0057 | 0.0012 | 0.010 | 1.75 | 0.249 | 0.125 | 0.021 | 0.012 | 0.0042 |
발명강 C | 0.045 | 0.123 | 1.92 | 0.0062 | 0.0011 | 0.011 | 1.82 | 0.254 | 0.119 | 0.013 | 0.013 | 0.0039 |
비교강 D | 0.126 | 0.123 | 1.88 | 0.0061 | 0.0012 | 0.010 | 1.80 | 0.249 | 0.121 | 0.017 | 0.011 | 0.0049 |
비교강 E | 0.052 | 0.118 | 1.91 | 0.0052 | 0.0014 | 0.015 | 1.68 | 0.261 | 0.052 | 0.02 | 0.012 | 0.0051 |
비교강 F | 0.046 | 0.121 | 1.89 | 0.0075 | 0.0013 | 0.012 | 1.76 | 0.248 | 0.125 | 0.008 | 0.010 | 0.0045 |
비교강 G | 0.048 | 0.119 | 1.25 | 0.0065 | 0.0013 | 0.013 | 0.65 | 0.253 | 0.132 | 0.018 | 0.012 | 0.0042 |
구분 | 강종 | 모재 | 선상가열 후 | ||||||
항복강도 | 인장강도 | 폴리고날 페라이트(부피%) | 충격인성 평균 | 항복강도 | 인장강도 | 충격인성 개별 | 충격인성 평균 | ||
발명예1 | 발명강 A | 527 | 665 | 7.5 | 278 | 514 | 661 | 267/262/253 | 260 |
513 | 649 | 265/288/302 | 285 | ||||||
532 | 642 | 277/322/326 | 308 | ||||||
507 | 627 | 194/130/184 | 170 | ||||||
비교예 1 | 발명강 A | 525 | 654 | 24.5 | 79 | 509 | 646 | 45/56/128 | 76 |
502 | 635 | 79/65/84 | 76 | ||||||
500 | 624 | 56/102/28 | 62 | ||||||
498 | 612 | 57/58/38 | 51 | ||||||
발명예 2 | 발명강 B | 538 | 672 | 6.7 | 247 | 534 | 668 | 245/167/158 | 190 |
529 | 659 | 264/286/302 | 284 | ||||||
518 | 642 | 268/231/188 | 229 | ||||||
510 | 621 | 154/186/109 | 150 | ||||||
비교예 2 | 발명강 B | 510 | 623 | 31.8 | 183 | 507 | 612 | 203/264/197 | 221 |
498 | 601 | 174/123/184 | 160 | ||||||
488 | 596 | 156/89/205 | 150 | ||||||
482 | 584 | 142/76/87 | 102 | ||||||
발명예 3 | 발명강 C | 542 | 671 | 7.9 | 281 | 538 | 664 | 221/265/287 | 258 |
531 | 659 | 234/212/264 | 237 | ||||||
528 | 640 | 198/187/234 | 206 | ||||||
513 | 627 | 265/188/203 | 219 | ||||||
비교예 3 | 비교강 D | 587 | 689 | 22.1 | 134 | 567 | 678 | 75/68/32 | 58 |
552 | 670 | 15/78/54 | 49 | ||||||
542 | 652 | 103/28/36 | 56 | ||||||
523 | 641 | 28/64/28 | 40 | ||||||
비교예 4 | 비교강 E | 524 | 625 | 35.5 | 226 | 514 | 615 | 52/105/39 | 65 |
508 | 611 | 64/103/154 | 107 | ||||||
501 | 602 | 51/136/121 | 103 | ||||||
492 | 598 | 25/38/65 | 43 | ||||||
비교예 5 | 비교강 F | 536 | 628 | 38.4 | 193 | 523 | 613 | 156/123/158 | 146 |
512 | 607 | 126/154/130 | 137 | ||||||
503 | 598 | 78/123/162 | 121 | ||||||
494 | 588 | 58/28/42 | 43 | ||||||
비교예 6 | 비교강 G | 506 | 624 | 42 | 133 | 503 | 611 | 120/175/56 | 117 |
493 | 608 | 89/45/37 | 57 | ||||||
483 | 594 | 36/48/56 | 47 | ||||||
479 | 578 | 59/21/34 | 38 |
Claims (6)
- 중량%로, C : 0.03 ~ 0.07%, Si : 0.05 ~ 0.2%, Mn : 1.6 ~ 2.3%, P : 0.008% 이하, S : 0.002% 이하, Al : 0.025% 이하, Cu : 0.1 ~ 0.4%, Ni : 1.4 ~ 2.3%, Mo : 0.08 ~ 0.2%, Nb : 0.01 ~ 0.025%, Ti : 0.008 ~ 0.02%, N: 0.001~0.008%, 나머지 Fe 및 불가피한 불순물을 포함하고,표면 10mm이내에서의 미세조직은 부피분율로 80%이상의 침상 페라이트 및 20% 이하의 폴리고날 페라이트를 포함하는 열간 저항성이 우수한 고강도 구조용 강판.
- 제1항에 있어서,상기 강판의 두께는 40mm이하인 것을 특징으로 하는 열간 저항성이 우수한 고강도 구조용 강판.
- 제1항에 있어서,상기 강판은 항복강도가 500MPa이상이며, 인장강도가 600MPa 이상이고, -40℃에서 충격인성이 100J 이상인 것을 특징으로 하는 열간 저항성이 우수한 고강도 구조용 강판.
- 제1항에 있어서,상기 강판은 600~900℃로 선상가열하고 곡가공한 후의 항복강도가 500MPa이상이며, 인장강도가 600MPa 이상이고, -40℃에서 충격인성이 100J 이상인 것을 특징으로 하는 열간 저항성이 우수한 고강도 구조용 강판.
- 중량%로, C : 0.03 ~ 0.07%, Si : 0.05 ~ 0.2%, Mn : 1.6 ~ 2.3%, P : 0.008% 이하, S : 0.002% 이하, Al : 0.025% 이하, Cu : 0.1 ~ 0.4%, Ni : 1.4 ~ 2.3%, Mo : 0.08 ~ 0.2%, Nb : 0.01 ~ 0.025%, Ti : 0.008 ~ 0.02%, N: 0.001~0.008%, 나머지 Fe 및 불가피한 불순물을 포함하는 슬라브를 재가열하는 단계;상기 재가열된 슬라브를 750~850℃에서 미재결정역 압연하는 단계; 및미재결정역 압연 후 10℃/초 이상의 냉각속도로 380~440℃의 냉각종료온도까지 냉각단계;를 포함하는 열간 저항성이 우수한 고강도 구조용 강판의 제조방법.
- 제5항에 있어서,상기 냉각된 강판을 600~900℃에서 선상가열한 후 곡가공하는 단계를 추가로 포함하는 것을 특징으로 하는 열간 저항성이 우수한 고강도 구조용 강판의 제조방법.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201680075866.6A CN108431276B (zh) | 2015-12-23 | 2016-12-21 | 抗热性优异的高强度结构用钢板及其制造方法 |
EP16879310.7A EP3395988B1 (en) | 2015-12-23 | 2016-12-21 | High-strength structural steel sheet excellent in hot resistance and manufacturing method thereof |
JP2018533626A JP6718510B2 (ja) | 2015-12-23 | 2016-12-21 | 熱間抵抗性に優れた高強度構造用鋼板及びその製造方法 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020150184775A KR101758520B1 (ko) | 2015-12-23 | 2015-12-23 | 열간 저항성이 우수한 고강도 구조용 강판 및 그 제조방법 |
KR10-2015-0184775 | 2015-12-23 |
Publications (2)
Publication Number | Publication Date |
---|---|
WO2017111443A1 true WO2017111443A1 (ko) | 2017-06-29 |
WO2017111443A8 WO2017111443A8 (ko) | 2017-10-26 |
Family
ID=59090640
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/KR2016/014964 WO2017111443A1 (ko) | 2015-12-23 | 2016-12-21 | 열간 저항성이 우수한 고강도 구조용 강판 및 그 제조방법 |
Country Status (5)
Country | Link |
---|---|
EP (1) | EP3395988B1 (ko) |
JP (1) | JP6718510B2 (ko) |
KR (1) | KR101758520B1 (ko) |
CN (1) | CN108431276B (ko) |
WO (1) | WO2017111443A1 (ko) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3730640A4 (en) * | 2017-12-24 | 2020-10-28 | Posco | THICK STEEL PLATE WITH EXCELLENT COLD RESISTANCE AND ITS MANUFACTURING PROCESS |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP6673320B2 (ja) * | 2017-02-16 | 2020-03-25 | Jfeスチール株式会社 | 厚鋼板および厚鋼板の製造方法 |
KR101949036B1 (ko) * | 2017-10-11 | 2019-05-08 | 주식회사 포스코 | 저온 변형시효 충격특성이 우수한 후강판 및 그 제조방법 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63183123A (ja) * | 1987-01-26 | 1988-07-28 | Kobe Steel Ltd | 線状及び点状再加熱加工後の低温靭性にすぐれる高張力鋼の製造方法 |
JPH11152540A (ja) * | 1997-11-18 | 1999-06-08 | Sumitomo Metal Ind Ltd | 線状加熱に伴う靱性劣化が少ない鋼材 |
JP2007056348A (ja) * | 2005-08-26 | 2007-03-08 | Nippon Steel Corp | 線状加熱による曲げ加工が容易な鋼板及びその製造方法 |
JP2010121149A (ja) * | 2008-11-17 | 2010-06-03 | Nippon Steel Corp | 線状加熱による曲げ加工性に優れた厚鋼板及びその製造方法 |
KR20110022308A (ko) * | 2009-08-27 | 2011-03-07 | 현대제철 주식회사 | 고강도 강재 및 그 제조방법 |
Family Cites Families (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2002235114A (ja) * | 2001-02-05 | 2002-08-23 | Kawasaki Steel Corp | 大入熱溶接部靱性に優れた厚肉高張力鋼の製造方法 |
KR100544638B1 (ko) * | 2001-12-24 | 2006-01-24 | 주식회사 포스코 | 항복강도 및 저온 파괴정지 특성이 우수한 후판강관구조용 강재의 제조방법 |
JP4066850B2 (ja) * | 2003-03-03 | 2008-03-26 | Jfeスチール株式会社 | 溶接部のctod特性に優れる高張力鋼の製造方法 |
JP4846242B2 (ja) * | 2005-01-25 | 2011-12-28 | 新日本製鐵株式会社 | 加熱曲げ特性に優れた厚鋼板の曲げ加工方法 |
KR100660230B1 (ko) | 2005-12-26 | 2006-12-21 | 주식회사 포스코 | 두께 중심부의 강도와 인성이 우수한 용접구조용 극후물강판 및 그 제조방법 |
EP2240618B1 (en) * | 2007-12-04 | 2013-01-23 | Posco | High-strength steel sheet with excellent low temperature toughness and manufacturing method thereof |
KR100957982B1 (ko) * | 2007-12-24 | 2010-05-17 | 주식회사 포스코 | Ctod 특성이 우수한 용접이음부를 포함하는용접구조용강 |
JP4308312B1 (ja) * | 2008-01-08 | 2009-08-05 | 新日本製鐵株式会社 | 線状加熱による曲げ加工性に優れた厚鋼板及びその製造方法 |
KR101360737B1 (ko) * | 2009-12-28 | 2014-02-07 | 주식회사 포스코 | 취성 균열 발생 저항성이 우수한 고강도 강판 및 그 제조방법 |
JP4897126B2 (ja) * | 2010-05-27 | 2012-03-14 | 新日本製鐵株式会社 | 厚鋼板の製造方法 |
KR20120075274A (ko) * | 2010-12-28 | 2012-07-06 | 주식회사 포스코 | 극저온 인성이 우수한 고강도 강판 및 그 제조방법 |
JP5833964B2 (ja) * | 2012-03-29 | 2015-12-16 | 株式会社神戸製鋼所 | 曲げ加工性、衝撃特性および引張特性に優れた鋼板およびその製造方法 |
KR101482359B1 (ko) * | 2012-12-27 | 2015-01-13 | 주식회사 포스코 | 극저온 인성이 우수하고 저항복비 특성을 갖는 고강도 강판 및 그의 제조방법 |
-
2015
- 2015-12-23 KR KR1020150184775A patent/KR101758520B1/ko active IP Right Grant
-
2016
- 2016-12-21 WO PCT/KR2016/014964 patent/WO2017111443A1/ko active Application Filing
- 2016-12-21 CN CN201680075866.6A patent/CN108431276B/zh active Active
- 2016-12-21 JP JP2018533626A patent/JP6718510B2/ja active Active
- 2016-12-21 EP EP16879310.7A patent/EP3395988B1/en active Active
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63183123A (ja) * | 1987-01-26 | 1988-07-28 | Kobe Steel Ltd | 線状及び点状再加熱加工後の低温靭性にすぐれる高張力鋼の製造方法 |
JPH11152540A (ja) * | 1997-11-18 | 1999-06-08 | Sumitomo Metal Ind Ltd | 線状加熱に伴う靱性劣化が少ない鋼材 |
JP2007056348A (ja) * | 2005-08-26 | 2007-03-08 | Nippon Steel Corp | 線状加熱による曲げ加工が容易な鋼板及びその製造方法 |
JP2010121149A (ja) * | 2008-11-17 | 2010-06-03 | Nippon Steel Corp | 線状加熱による曲げ加工性に優れた厚鋼板及びその製造方法 |
KR20110022308A (ko) * | 2009-08-27 | 2011-03-07 | 현대제철 주식회사 | 고강도 강재 및 그 제조방법 |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3730640A4 (en) * | 2017-12-24 | 2020-10-28 | Posco | THICK STEEL PLATE WITH EXCELLENT COLD RESISTANCE AND ITS MANUFACTURING PROCESS |
Also Published As
Publication number | Publication date |
---|---|
EP3395988A1 (en) | 2018-10-31 |
EP3395988C0 (en) | 2024-02-07 |
EP3395988B1 (en) | 2024-02-07 |
CN108431276B (zh) | 2020-04-14 |
KR101758520B1 (ko) | 2017-07-17 |
EP3395988A4 (en) | 2019-02-27 |
CN108431276A (zh) | 2018-08-21 |
JP2019505676A (ja) | 2019-02-28 |
KR20170075851A (ko) | 2017-07-04 |
JP6718510B2 (ja) | 2020-07-08 |
WO2017111443A8 (ko) | 2017-10-26 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2016104975A1 (ko) | Pwht 후 인성이 우수한 고강도 압력용기용 강재 및 그 제조방법 | |
WO2017111510A1 (ko) | 열간 가공성이 우수한 비자성 강재 및 그 제조방법 | |
WO2018110853A1 (ko) | 저온역 버링성이 우수한 고강도 복합조직강 및 그 제조방법 | |
WO2018117646A1 (ko) | 극저온 충격인성이 우수한 후강판 및 이의 제조방법 | |
WO2018004297A1 (ko) | 저항복비 특성 및 저온인성이 우수한 고강도 강판 및 그 제조방법 | |
WO2019125083A1 (ko) | 우수한 경도와 충격인성을 갖는 내마모강 및 그 제조방법 | |
WO2018117497A1 (ko) | 길이방향 균일 연신율이 우수한 용접강관용 강재, 이의 제조방법 및 이를 이용한 강관 | |
WO2018117450A1 (ko) | 저온인성 및 후열처리 특성이 우수한 내sour 후판 강재 및 그 제조방법 | |
WO2018117614A1 (ko) | 표면부 nrl-dwt 물성이 우수한 극후물 강재 및 그 제조방법 | |
WO2018117700A1 (ko) | 고강도 고인성 후강판 및 이의 제조방법 | |
WO2012043984A2 (ko) | 수소유기균열 저항성이 우수한 라인 파이프용 강판 및 그 제조 방법 | |
WO2018117507A1 (ko) | 저온인성이 우수한 저항복비 강판 및 그 제조방법 | |
WO2017111443A1 (ko) | 열간 저항성이 우수한 고강도 구조용 강판 및 그 제조방법 | |
WO2020111856A2 (ko) | 연성 및 저온 인성이 우수한 고강도 강재 및 이의 제조방법 | |
WO2019124814A1 (ko) | 수소유기균열 저항성 및 길이방향 강도 균일성이 우수한 강판 및 그 제조방법 | |
WO2019124765A1 (ko) | 내충격특성이 우수한 고강도 강판 및 그 제조방법 | |
WO2020111891A1 (ko) | 저온파괴인성 및 연신율이 우수한 고강도 강판 및 그 제조방법 | |
WO2013154254A1 (ko) | 재질 균일성이 우수한 고탄소 열연강판 및 이의 제조방법 | |
WO2016105003A1 (ko) | 취성균열전파 저항성이 우수한 구조용 극후물 강재 및 그 제조방법 | |
WO2022065797A1 (ko) | 연신율이 우수한 고강도 후물 열연강판 및 그 제조방법 | |
WO2017086745A1 (ko) | 전단가공성이 우수한 고강도 냉연강판 및 그 제조방법 | |
WO2021261884A1 (ko) | 생산성 및 원가 절감 효과가 우수한 고강도 오스테나이트계 스테인리스강 및 이의 제조방법 | |
WO2018117727A1 (ko) | 저온 충격인성 및 ctod 특성이 우수한 후강판 및 그 제조방법 | |
WO2023090735A1 (ko) | 열연강판 및 그 제조방법 | |
WO2024136354A1 (ko) | 열연강판 및 그 제조방법 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 16879310 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 2018533626 Country of ref document: JP Kind code of ref document: A |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2016879310 Country of ref document: EP |
|
ENP | Entry into the national phase |
Ref document number: 2016879310 Country of ref document: EP Effective date: 20180723 |