CN108474090B - Low yield ratio high strength steel material and method for producing same - Google Patents
Low yield ratio high strength steel material and method for producing same Download PDFInfo
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- CN108474090B CN108474090B CN201680075889.7A CN201680075889A CN108474090B CN 108474090 B CN108474090 B CN 108474090B CN 201680075889 A CN201680075889 A CN 201680075889A CN 108474090 B CN108474090 B CN 108474090B
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 84
- 239000010959 steel Substances 0.000 title claims abstract description 84
- 239000000463 material Substances 0.000 title claims abstract description 52
- 238000004519 manufacturing process Methods 0.000 title claims description 24
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims abstract description 24
- 239000010955 niobium Substances 0.000 claims abstract description 19
- 239000011651 chromium Substances 0.000 claims abstract description 17
- 239000011572 manganese Substances 0.000 claims abstract description 17
- 239000010936 titanium Substances 0.000 claims abstract description 17
- 239000011575 calcium Substances 0.000 claims abstract description 16
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 14
- 239000012535 impurity Substances 0.000 claims abstract description 9
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 8
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 8
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims abstract description 7
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims abstract description 7
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 7
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims abstract description 7
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 claims abstract description 7
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims abstract description 7
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 7
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims abstract description 7
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims abstract description 7
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims abstract description 7
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 7
- 229910052796 boron Inorganic materials 0.000 claims abstract description 7
- 229910052791 calcium Inorganic materials 0.000 claims abstract description 7
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 7
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 7
- 229910052748 manganese Inorganic materials 0.000 claims abstract description 7
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 7
- 229910052758 niobium Inorganic materials 0.000 claims abstract description 7
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims abstract description 7
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 7
- 229910052698 phosphorus Inorganic materials 0.000 claims abstract description 7
- 239000011574 phosphorus Substances 0.000 claims abstract description 7
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 7
- 239000010703 silicon Substances 0.000 claims abstract description 7
- 229910052717 sulfur Inorganic materials 0.000 claims abstract description 7
- 239000011593 sulfur Substances 0.000 claims abstract description 7
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 7
- 229910001563 bainite Inorganic materials 0.000 claims description 21
- 238000001816 cooling Methods 0.000 claims description 20
- 238000005096 rolling process Methods 0.000 claims description 17
- 229910000859 α-Fe Inorganic materials 0.000 claims description 17
- 239000010949 copper Substances 0.000 claims description 11
- 239000013078 crystal Substances 0.000 claims description 11
- 238000005098 hot rolling Methods 0.000 claims description 6
- 238000010438 heat treatment Methods 0.000 claims description 5
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 4
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims description 4
- 229910052802 copper Inorganic materials 0.000 claims description 4
- 229910052750 molybdenum Inorganic materials 0.000 claims description 4
- 239000011733 molybdenum Substances 0.000 claims description 4
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 claims description 4
- 230000009467 reduction Effects 0.000 claims description 3
- 239000004615 ingredient Substances 0.000 claims 1
- 230000000694 effects Effects 0.000 description 14
- 229910001566 austenite Inorganic materials 0.000 description 9
- 230000007423 decrease Effects 0.000 description 9
- 229910000734 martensite Inorganic materials 0.000 description 8
- 238000000034 method Methods 0.000 description 8
- 229910045601 alloy Inorganic materials 0.000 description 6
- 239000000956 alloy Substances 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 4
- 230000007797 corrosion Effects 0.000 description 4
- 238000005260 corrosion Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 238000001953 recrystallisation Methods 0.000 description 4
- 238000010276 construction Methods 0.000 description 3
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- 230000001771 impaired effect Effects 0.000 description 3
- 230000006872 improvement Effects 0.000 description 3
- 238000003466 welding Methods 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 2
- 238000009749 continuous casting Methods 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
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- 238000003754 machining Methods 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 238000010791 quenching Methods 0.000 description 2
- 230000000171 quenching effect Effects 0.000 description 2
- 238000010008 shearing Methods 0.000 description 2
- 239000006104 solid solution Substances 0.000 description 2
- 230000035882 stress Effects 0.000 description 2
- 238000005496 tempering Methods 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 229910001035 Soft ferrite Inorganic materials 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000003486 chemical etching Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
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- 238000001887 electron backscatter diffraction Methods 0.000 description 1
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- 239000007789 gas Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
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- 238000005498 polishing Methods 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000004080 punching Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 238000003303 reheating Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000009628 steelmaking Methods 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 238000009864 tensile test Methods 0.000 description 1
- RMLPZKRPSQVRAB-UHFFFAOYSA-N tris(3-methylphenyl) phosphate Chemical compound CC1=CC=CC(OP(=O)(OC=2C=C(C)C=CC=2)OC=2C=C(C)C=CC=2)=C1 RMLPZKRPSQVRAB-UHFFFAOYSA-N 0.000 description 1
Classifications
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- 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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/58—Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese
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- 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
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- 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
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- 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
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- 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
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- 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
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- 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
- C22C38/008—Ferrous alloys, e.g. steel alloys containing tin
-
- 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
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- 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
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- 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
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- 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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
-
- 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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
-
- 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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/46—Ferrous alloys, e.g. steel alloys containing chromium with nickel with vanadium
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- 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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/48—Ferrous alloys, e.g. steel alloys containing chromium with nickel with niobium or tantalum
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- 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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/50—Ferrous alloys, e.g. steel alloys containing chromium with nickel with titanium or zirconium
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- 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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/54—Ferrous alloys, e.g. steel alloys containing chromium with nickel with boron
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- 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
- C21D2211/002—Bainite
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- 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
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- 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
- C21D2211/008—Martensite
Abstract
One aspect of the present invention relates to a low yield ratio high strength steel material comprising carbon (C): 0.02 to 0.11 wt%, silicon (Si): 0.1 to 0.5 wt%, manganese (Mn): 1.5 to 2.5% by weight, aluminum (Al): 0.01 to 0.06 wt%, nickel (Ni): 0.1 to 0.6 wt%, titanium (Ti): 0.01 to 0.03 wt%, niobium (Nb): 0.005-0.08 wt%, chromium (Cr): 0.1 to 0.5% by weight, phosphorus (P): 0.01 wt% or less (excluding 0 wt%), sulfur (S): 0.01 wt% or less (excluding 0 wt%), boron (B): 5-30 ppm by weight, nitrogen (N): 20 to 70 ppm by weight, calcium (Ca): 50ppm by weight or less (excluding 0ppm by weight), tin (Sn): 5 to 50ppm by weight (excluding 0ppm by weight), and the balance of iron (Fe) and other unavoidable impurities.
Description
Technical Field
The present invention relates to a low yield ratio high strength steel material and a method for producing the same. More particularly, the present invention relates to a low yield ratio high strength steel material having a low yield ratio and a high tensile strength suitable for use as a steel material for construction and a method for manufacturing the same.
Background
Recently, buildings such as high buildings and bridges at home and abroad tend to have super high floors and large spans, and therefore, development of super-thick and high-strength steel materials is required. When high-strength steel is used, it has a high allowable stress, so that it is possible to rationalize and reduce the weight of a building and a bridge structure, and to make the construction economical, and to make the thickness of a plate thin, so that machining such as shearing or punching and welding operations become easy.
Further, when the strength of a steel material is increased, the yield ratio (yield strength/tensile strength), which is the ratio of tensile strength to yield strength, is increased in many cases, and if the yield ratio is increased, the difference in stress from the time when plastic deformation occurs (yield point) to the time when failure occurs is not large, so that the time for preventing failure of a building by absorbing energy through deformation is not long, and it is difficult to ensure safety when a large external force such as an earthquake is applied to the building. Therefore, structural steels need to satisfy both high strength and low yield ratio.
Further, it is considered that the yield ratio of the steel material can be reduced by appropriately dispersing a hard phase (hard phase) such as bainite (bainite) or martensite (martentite) in the microstructure of the steel material with a soft phase (ferrite) or the like as a main structure.
In order to obtain a microstructure in which a hard phase is appropriately dispersed in a soft phase-based microstructure as described above, patent document 1 discloses a method in which a yield ratio can be reduced by appropriately quenching (quenching) and tempering (tempering) in a two-phase region (dual phase region) of ferrite and austenite (austenite). However, the method has an inevitable problem in that the number of heat treatment processes is increased in addition to the rolling process, so that productivity is apparently decreased, and the manufacturing unit price is increased.
Therefore, it is required to develop a low yield ratio high strength steel material and a method for manufacturing the same, which can solve the problems of the decrease in productivity and the increase in manufacturing unit cost and ensure an ultrahigh strength and a low yield ratio.
Prior art documents
Patent document 1: japanese patent laid-open No. 55-97425
Disclosure of Invention
Technical problem
One aspect of the present invention is directed to a low yield ratio high strength steel material and a method of manufacturing the same. More specifically, the present invention aims to provide a low-yield-ratio high-strength steel material and a method for manufacturing the same, which can ensure ultrahigh strength and low yield ratio, and which does not decrease productivity and does not increase manufacturing unit price.
In addition, the technical problems to be solved by the present invention are not limited to the above-mentioned matters, and the technical problems to be solved by the present invention can be understood through the whole content of the present specification, and it is not difficult for those skilled in the art to understand the additional technical problems of the present invention.
Technical scheme
One aspect of the present invention relates to a low yield ratio high strength steel material comprising the following components: carbon (C): 0.02 to 0.11 wt%, silicon (Si): 0.1 to 0.5 wt%, manganese (Mn): 1.5 to 2.5% by weight, aluminum (Al): 0.01 to 0.06 wt%, nickel (Ni): 0.1 to 0.6 wt%, titanium (Ti): 0.01 to 0.03 wt%, niobium (Nb): 0.005-0.08 wt%, chromium (Cr): 0.1 to 0.5% by weight, phosphorus (P): 0.01 wt% or less (excluding 0 wt%), sulfur (S): 0.01 wt% or less (excluding 0 wt%), boron (B): 5-30 ppm by weight, nitrogen (N): 20 to 70 ppm by weight, calcium (Ca): 50ppm by weight or less (excluding 0ppm by weight), tin (Sn): 5 to 50ppm by weight (excluding 0ppm by weight), and the balance of iron (Fe) and other unavoidable impurities.
In addition, another aspect of the present invention provides a method for manufacturing a low yield ratio high strength steel material, including the steps of:
heating a steel slab to 1050-1250 ℃, said steel slab comprising carbon (C): 0.02 to 0.11 wt%, silicon (Si): 0.1 to 0.5 wt%, manganese (Mn): 1.5 to 2.5% by weight, aluminum (Al): 0.01 to 0.06 wt%, nickel (Ni): 0.1 to 0.6 wt%, titanium (Ti): 0.01 to 0.03 wt%, niobium (Nb): 0.005-0.08 wt%, chromium (Cr): 0.1 to 0.5% by weight, phosphorus (P): 0.01 wt% or less (excluding 0 wt%), sulfur (S): 0.01 wt% or less (excluding 0 wt%), boron (B): 5-30 ppm by weight, nitrogen (N): 20 to 70 ppm by weight, calcium (Ca): 50ppm by weight or less (excluding 0ppm by weight), tin (Sn): 5 to 50ppm by weight (excluding 0ppm by weight), and the balance of iron (Fe) and other unavoidable impurities;
roughly rolling the heated billet at 950-1150 ℃ to obtain a steel Bar (Bar);
hot rolling the steel Bar (Bar) at a finishing temperature of 700-950 ℃ to obtain a hot-rolled steel plate; and
and cooling the hot-rolled steel sheet to a cooling completion temperature of the Bs temperature or lower at a cooling rate of 25 ℃/s to 50 ℃/s.
Incidentally, the above-described technical problem solutions do not list all the features of the present invention. The features of the present invention and the advantages and effects based on the features are described in further detail with reference to the following detailed description.
Advantageous effects
According to the present invention, it is possible to provide a low yield ratio and high strength steel material which can ensure an ultrahigh strength and a low yield ratio, and which does not decrease productivity and does not increase production cost, and a method for manufacturing the same.
Detailed Description
Preferred embodiments of the present invention are set forth below. However, the present invention can be modified in various ways, and the scope of the present invention is not limited to the following embodiments. In addition, embodiments of the present invention are provided to more fully explain the present invention to those of ordinary skill in the art.
The low yield ratio high strength steel material according to one aspect of the present invention is explained in detail below.
A low yield ratio high strength steel material according to one aspect of the present invention comprises the following components: carbon (C): 0.02 to 0.11 wt%, silicon (Si): 0.1 to 0.5 wt%, manganese (Mn): 1.5 to 2.5% by weight, aluminum (A1): 0.01 to 0.06 wt%, nickel (Ni): 0.1 to 0.6 wt%, titanium (Ti): 0.01 to 0.03 wt%, niobium (Nb): 0.005-0.08 wt%, chromium (Cr): 0.1 to 0.5% by weight, phosphorus (P): 0.01 wt% or less (excluding 0 wt%), sulfur (S): 0.01 wt% or less (excluding 0 wt%), boron (B): 5-30 ppm by weight, nitrogen (N): 20 to 70 ppm by weight, calcium (Ca): 50ppm by weight or less (excluding 0ppm by weight), tin (Sn): 5 to 50ppm by weight (excluding 0ppm by weight), and the balance of iron (Fe) and other unavoidable impurities.
Carbon (C): 0.02 to 0.11% by weight
C is an important element that forms bainite or martensite and determines the size and fraction of bainite or martensite formed.
If the content of C is more than 0.11 wt%, it results in a decrease in low-temperature toughness, and if the content of C is less than 0.02 wt%, it interferes with the formation of bainite or martensite, thereby causing a decrease in strength. Therefore, the C content is preferably 0.02 to 0.11 wt%.
Further, for the plate material used as the steel structure for welding, the upper limit of the C content is more preferably limited to 0.08 wt% for better weldability.
Silicon (Si): 0.1 to 0.5% by weight
Si is an element that acts as a deoxidizer and improves strength and toughness.
If the Si content is more than 0.5 wt%, not only the low-temperature toughness and weldability are degraded, but also thick scale (scale) is formed on the surface of the plate material, possibly resulting in poor gas cutting properties and other surface cracks. If the Si content is less than 0.1 wt%, the deoxidation effect may be insufficient. Therefore, the Si content may be preferably 0.1 wt% to 0.5 wt%, and more preferably 0.15 wt% to 0.35 wt%.
Manganese (Mn): 1.5 to 2.5% by weight
Mn is a useful element for improving strength by solid solution strengthening, and therefore, it is necessary to add 1.5 wt% or more. However, if the Mn content is more than 2.5 wt%, hardenability may be excessively increased, which may cause a significant decrease in toughness of the weld. Therefore, the content of Mn is preferably 1.5 wt% to 2.5 wt%.
Aluminum (a 1): 0.01 to 0.06 wt.%
Al is an element that can deoxidize molten steel at a low cost and stabilize ferrite. If the Al content is less than 0.01 wt%, the above-mentioned effects are insufficient. If the Al content is more than 0.06 wt%, nozzle clogging may occur during continuous casting. Therefore, the Al content is preferably 0.01 to 0.06 wt%.
Nickel (Ni): 0.1 to 0.6% by weight
Ni is an element that can improve both the strength and toughness of the base material. In the present invention, in order to sufficiently exhibit the above-mentioned effects, it is preferable to add 0.1% by weight or more. However, since Ni is an expensive element, if the amount added is more than 0.6 wt%, it causes deterioration in economical efficiency and also may cause deterioration in weldability. Therefore, the Ni content is preferably 0.1% to 0.6%.
Titanium (Ti): 0.01 to 0.03 percent by weight
Ti is preferably added in an amount of 0.01 wt% or more because it suppresses grain growth during reheating and greatly improves low-temperature toughness. However, if the Ti content is more than 0.03 wt%, there is a possibility that the continuous casting nozzle may be clogged or the low-temperature toughness may be lowered due to crystallization in the center portion. Therefore, the Ti content is preferably 0.01 to 0.03 wt%.
Niobium (Nb): 0.005 to 0.08% by weight
Nb is an important element for producing TMCP steel, and is precipitated in the form of NbC or NbCN, thereby greatly improving the strength of the base material and the welded portion. Further, when reheated at high temperature, the solid-dissolved Nb suppresses recrystallization of austenite and transformation of ferrite or bainite, thereby exhibiting an effect of refining the structure. Further, in the present invention, when the billet is cooled after rough rolling, bainite formation is promoted even at a low cooling rate, and when the billet is cooled after final rolling, the stability of austenite is improved, and martensite formation is promoted even at a low cooling rate.
In order to sufficiently obtain the above-mentioned effects, the content of Nb is preferably 0.005% by weight or more. However, if the Nb content exceeds 0.08 wt%, brittle cracks may occur at the edges of the steel. Therefore, the Nb content is preferably 0.005 wt% to 0.08 wt%.
Chromium (Cr): 0.1 to 0.5% by weight
Cr is an element added to secure strength and also plays a role in increasing hardenability. In order to sufficiently obtain the above-mentioned effects, it is necessary to add 0.1% or more. However, if the Cr content exceeds 0.5%, the hardness of the weld portion may be excessively increased, and the toughness may be impaired. Therefore, the Cr content is preferably 0.1% to 0.5%.
Phosphorus (P): less than or equal to 0.01% by weight
P is an element which is advantageous for strength improvement and corrosion resistance, but greatly impairs impact toughness, and is preferably kept as low as possible, so the upper limit of the P content is preferably 0.01% by weight.
Sulfur (S): less than or equal to 0.01% by weight
S forms MnS or the like to greatly impair impact toughness, and is preferably kept as low as possible, so the upper limit of the S content is preferably 0.01% by weight.
Boron (B): 5 to 30 ppm by weight
B is a very inexpensive additive element exhibiting strong hardenability and contributes significantly to the formation of bainite in the case of low-speed cooling after rough rolling.
A small amount of B also greatly improves the strength, so that 5ppm by weight or more may be added. However, if the B content is more than 30 weight ppm, Fe is formed23(CB)6On the contrary, the hardenability may be lowered, and the low-temperature toughness may be also largely lowered. Therefore, the B content is preferably 5 to 30 ppm by weight.
Nitrogen (N): 20 to 70 ppm by weight
N increases the strength but greatly reduces the toughness, and therefore, it is preferably controlled to 70 weight ppm or less. However, since the steel making load is increased if the N content is controlled to less than 20 weight ppm, the lower limit of the N content is preferably 20 weight ppm.
Calcium (Ca): less than or equal to 60 ppm by weight (except 0)
Ca is mainly used as an element for suppressing MnS nonmetallic inclusions and improving low-temperature toughness. However, since excessive addition of Ca causes reaction with oxygen contained in steel to produce CaO as a nonmetallic inclusion, the upper limit value is preferably 60 ppm by weight.
Tin (Sn): 5 to 50ppm by weight
Sn is an element useful for ensuring corrosion resistance.
From the viewpoint of ensuring corrosion resistance, it is preferably added in an amount of 5ppm or more. However, if the Sn content is more than 50ppm by weight, there is a higher possibility that the defect of the shape of the oxide scale bulging or cracking like blisters appears on the steel surface in large amount than the contribution to the improvement of the corrosion resistance. Further, Sn increases the strength of the steel, but decreases the elongation and low-temperature impact toughness, so the upper limit of the Sn content is preferably 50 weight ppm.
The balance of the present invention is iron (Fe). However, the conventional manufacturing process inevitably involves mixing of unexpected impurities derived from raw materials or the surrounding environment, and thus the mixing of impurities cannot be excluded. These impurities are known to anyone skilled in the art of conventional manufacturing processes and therefore all relevant details are not repeated in this specification.
The steel material having the advantageous steel component of the present invention described above can obtain sufficient effects only by containing the alloying elements within the above content range, but may further contain copper (Cu): 0.1 to 0.5 wt%, molybdenum (Mo): 0.15 to 0.3 wt.% and vanadium (V): 0.005 to 0.3% by weight of at least one element to further improve the strength and toughness of the steel material and the toughness and weldability of the weld heat affected zone.
Copper (Cu): 0.1 to 0.5% by weight
Cu is an element that minimizes a decrease in toughness of the base material and can simultaneously improve strength. In order to sufficiently obtain the above-mentioned effects, it is preferable to add 0.1% by weight or more. However, if the Cu content is more than 0.5% by weight, the surface quality of the product may be greatly impaired. Therefore, the Cu content is preferably 0.1 to 0.5 wt%.
Molybdenum (Mo): 0.15 to 0.3% by weight
Mo has an effect of greatly improving hardenability even when added in a small amount, and can greatly improve strength, so that addition of 0.15 wt% or more is necessary, but if the amount is more than 0.3 wt%, hardness of a weld portion is excessively increased, and toughness may be impaired. Therefore, the Mo content is preferably 0.15 to 0.3 wt%.
Vanadium (V): 0.005 to 0.3% by weight
V has a lower solid solution temperature than other fine alloys, precipitates in the weld heat affected zone, and has the effect of preventing a decrease in strength. In order to sufficiently obtain the above-mentioned effects, it is preferable to add 0.005% by weight or more. However, if the V content is more than 0.3% by weight, the toughness is rather lowered. Therefore, the V content is preferably 0.005 wt% to 0.3 wt%.
The microstructure of the steel material of the present invention may contain bainitic ferrite and granular bainite as a main phase, and may contain M-a (island martensite) as a secondary phase.
Bainitic ferrite maintains the initial austenite grain boundaries and contains many large-angle grain boundaries within the grains, thereby contributing to the improvement of strength and impact toughness based on the grain refinement effect.
Granular bainite retains the original austenite grains as does bainitic ferrite, but secondary phases such as M-A exist within the grains or grain boundaries. The impact toughness is somewhat unfavorable because large-angle grain boundaries do not exist in the crystal, but small-angle grain boundaries such as dislocations exist in large amounts in the crystal, and the strength is somewhat increased.
The inclusion of bainitic ferrite and granular bainite as the main phase can ensure a low yield ratio and high strength.
In this case, the bainitic ferrite may be 80% to 95%, the granular bainite may be 5% to 20%, and the M-a may be 3% or less (including 0%) in area fraction.
If the area fraction of bainitic ferrite is less than 80%, it is difficult to secure high tensile strength, and if it exceeds 95%, the yield ratio increases.
If the area fraction of the granular bainite is less than 5%, not only the tensile strength increases, but also the yield strength increases, and a low yield ratio cannot be secured, and if it exceeds 20%, coarse initial austenite grains cannot be effectively refined, possibly resulting in deterioration of the tensile strength.
The secondary phase such as M-a is a fine structure advantageous for achieving a low yield ratio, and preferably has an area fraction of 3% or less. If the area fraction of M-A is more than 3%, the yield ratio may be decreased, but it may be relatively a starting point of crack (crack) due to external stress, and thus it is not preferable to secure high tensile strength.
In addition, for the steel material of the present invention, PImax. (111)/PImax. (100) may be 1.0 or more and 1.8 or less. The PImax. (111) is a pole intensity (PImax.) of a (111) crystal plane obtained by X-ray diffraction, electron backscatter diffraction, or the like, and the PImax. (100) is a pole intensity of a (100) crystal plane.
The intensity of the pole of the crystal plane depends on the final microstructure of the steel material according to an aspect of the present invention. When bainitic ferrite and granular bainite are used as the main phase, the higher the fraction of bainitic ferrite, the higher the value of PImax. (111), and the higher the fraction of granular bainite, the higher the value of PImax. (100). The steel material according to one aspect of the present invention has a final microstructure in which the area fraction of bainitic ferrite is higher than that of granular bainite, and when PI max (111)/PImax (100) is 1.8 or less, a low yield ratio high strength steel material can be produced. When PImax. (111)/PImax. (100) is greater than 1.8, the low yield ratio cannot be satisfied, and therefore, the upper limit value thereof is preferably 1.8 or less. More preferably, PImax. (111)/PImax. (100) is 1.6 or less.
If PImax. (111)/PImax. (100) is less than 1.0, the fraction of granular bainite becomes higher than 20%, which causes a problem that it is difficult to secure high strength. Therefore, the lower limit of PImax. (111)/PImax. (100) is preferably 1.0 or more, and more preferably 1.2 or more.
The steel material of the present invention can be used as a steel material for construction or the like because it can ensure a yield ratio of 0.85 or less and a tensile strength of 800MPa or more.
Further, the thickness of the steel material according to the present invention may be 60mm or less.
The steel material according to the present invention can ensure high strength and low yield ratio, and can make the thickness of the plate material as thin as 60mm or less, thereby facilitating the machining and welding operations such as shearing and piercing. Therefore, the thickness of the steel material is preferably 60mm or less, more preferably 40mm or less, and still more preferably 30mm or less.
The lower limit of the thickness of the steel material is not particularly limited, but may be 15mm or more for use as a steel material for building structures.
The method for producing a low yield ratio high strength steel material according to another aspect of the present invention will be described in detail below.
Another aspect of the present invention is a method for producing a low yield ratio high strength steel material, including the steps of: heating the steel billet with the alloy components to 1050-1250 ℃; roughly rolling the heated billet at 950-1150 ℃ to obtain a steel Bar (Bar); hot rolling the steel Bar (Bar) at a finishing temperature of 700-950 ℃ to obtain a hot-rolled steel plate; and cooling the hot-rolled steel sheet to a cooling finish temperature of the Bs temperature or lower at a cooling rate of 25 ℃/s to 50 ℃/s.
Billet heating step
The steel billet with the alloy components is heated to 1050-1250 ℃.
Rough rolling step
And roughly rolling the heated steel billet at 950-1050 ℃ to obtain a steel Bar (Bar).
If the rough rolling temperature is lower than 950 ℃, austenite is deformed in a state where recrystallization does not occur, and thus grain coarsening may be caused, and if it is higher than 1050 ℃, recrystallization occurs while grain growth may be caused, and austenite grain coarsening may be caused.
Step of Hot Rolling
And hot-rolling the steel Bar (Bar) at a finishing temperature of 700 ℃ to 950 ℃ to obtain a hot-rolled steel sheet.
If the finish rolling temperature is less than 700 c, the rolling mill may not be rolled to a final thickness due to a load generated by the rolling mill due to a low temperature of the plate, and if it is more than 950 c, recrystallization may occur during the rolling process.
At this time, the reduction ratio of the hot rolling may be 50% to 80%.
If the final reduction ratio is less than 50%, the load applied to the material during rolling may increase, which may cause equipment failure, and if it exceeds 80%, the number of rolling passes may increase, which may result in failure to secure the final thickness up to the rolling end temperature.
Step of Cooling
And cooling the hot-rolled steel sheet to a cooling completion temperature of the Bs temperature or lower at a cooling rate of 25 ℃/s to 50 ℃/s.
When the cooling of the hot-rolled steel sheet is completed at a temperature higher than the Bs temperature, bainitic ferrite and granular bainite cannot be transformed sufficiently, and thus strength cannot be secured. The cooling rate is physically limited depending on the thickness of the plate material, but it is difficult to satisfy a tensile strength of 800MPa or more because soft ferrite is generated at a cooling rate of less than 25 ℃/s. Further, since the probability that martensite is generated in the low-temperature transformation structure at a cooling rate of more than 50 ℃/s becomes high, not only the tensile strength but also the yield strength increases, and it is difficult to satisfy the yield ratio of 0.85 or less.
The present invention is described in more detail below by way of examples. It should be noted, however, that the following examples are for the purpose of describing specific examples of the present invention only, and are not intended to limit the scope of the claims of the present invention. The scope of the claims of the present invention depends on the contents of the claims and reasonable derivation thereof.
A steel slab satisfying the composition shown in table 1 below was heated to 1160 c, rough rolled at 1000 c, and then hot rolled and cooled in such a manner as to satisfy the manufacturing conditions shown in table 2 below, thereby obtaining a steel product. The yield strength, tensile strength, yield ratio and microstructure of the steel material were measured and are shown in table 3 below.
Further, the values of PImax. (111)/PImax. (100) after the pole strength of the (100) crystal plane and the (110) crystal plane of the steel material was measured are shown in table 3 below.
The yield strength and tensile strength were measured by a universal tensile testing machine.
The microstructure was observed by chemical etching after mirror polishing of the steel material with an optical microscope.
The pole intensity and texture intensity were measured by an X-ray diffractometer and an electron back-scattering diffractometer.
The unit of the content of each element in table 1 below is weight%.
[ TABLE 1 ]
[ TABLE 2 ]
[ TABLE 3 ]
In table 3 above, BF represents bainitic ferrite, GB represents granular bainite, MA represents island-like martensite, AF represents acicular ferrite, and B represents bainite, the unit being area%.
The invention examples 1 to 9 satisfying the alloy composition and the production conditions of the present invention can secure a low yield ratio of 0.85 or less and a tensile strength of 800MPa or more.
In contrast, comparative examples 1 to 3, although satisfying the alloy composition of the present invention, did not satisfy the production conditions, and thus could not ensure a low yield ratio or a poor tensile strength.
In addition, comparative examples 4, 7 and 8, although satisfying the manufacturing conditions of the present invention, do not satisfy the alloy composition, and thus cannot ensure a low yield ratio.
The present invention has been described above with reference to the embodiments, but various modifications and changes can be made by those skilled in the art without departing from the technical idea and field of the present invention described in the claims.
Claims (6)
1. A low yield ratio high strength steel material comprising the following components:
carbon (C): 0.02 to 0.11 wt%, silicon (Si): 0.1 to 0.5 wt%, manganese (Mn): 1.5 to 2.5% by weight, aluminum (Al): 0.01 to 0.06 wt%, nickel (Ni): 0.1 to 0.6 wt%, titanium (Ti): 0.01 to 0.03 wt%, niobium (Nb): 0.005-0.08 wt%, chromium (Cr): 0.1 to 0.5% by weight, phosphorus (P): 0.01 wt% or less, sulfur (S): 0.01 wt% or less, boron (B): 5-30 ppm by weight, nitrogen (N): 20 to 70 ppm by weight, calcium (Ca): 50ppm by weight or less and 0 is excluded, tin (Sn): 5 to 50ppm by weight, the balance being iron (Fe) and other unavoidable impurities,
wherein the fine structure of the steel material is composed of 80-95 area% bainitic ferrite, 5-20 area% granular bainite, 0-3 area% M-A or more, and unavoidable phases,
wherein a ratio PImax (111)/PImax (100) of a pole intensity of a (100) crystal plane and a pole intensity of a (111) crystal plane of the steel material is 1.0 or more and 1.8 or less, wherein the PImax (111) is the pole intensity of the (111) crystal plane, the PImax (100) is the pole intensity of the (100) crystal plane, and
wherein the yield ratio of the steel is less than or equal to 0.85, and the tensile strength is greater than or equal to 800 MPa.
2. A low yield ratio high strength steel product according to claim 1, further comprising the following ingredients:
copper (Cu): 0.1 to 0.5 wt%, molybdenum (Mo): 0.15 to 0.3 wt.% and vanadium (V): 0.005 to 0.3% by weight of at least one element.
3. The steel material with a low yield ratio and a high strength according to claim 1, wherein:
the thickness of the steel is less than or equal to 60 mm.
4. A method of manufacturing a low yield ratio high strength steel material as claimed in claim 1, comprising the steps of:
heating a steel slab to 1050-1250 ℃, said steel slab comprising carbon (C): 0.02 to 0.11 wt%, silicon (Si): 0.1 to 0.5 wt%, manganese (Mn): 1.5 to 2.5% by weight, aluminum (Al): 0.01 to 0.06 wt%, nickel (Ni): 0.1 to 0.6 wt%, titanium (Ti): 0.01 to 0.03 wt%, niobium (Nb): 0.005-0.08 wt%, chromium (Cr): 0.1 to 0.5% by weight, phosphorus (P): 0.01 wt% or less, sulfur (S): 0.01 wt% or less, boron (B): 5-30 ppm by weight, nitrogen (N): 20 to 70 ppm by weight, calcium (Ca): 50ppm by weight or less and 0 is excluded, tin (Sn): 5 to 50ppm by weight, the balance being iron (Fe) and other unavoidable impurities;
roughly rolling the heated billet at 950-1050 ℃ to obtain a steel bar;
carrying out hot rolling on the steel bar at the finishing temperature of 700-950 ℃ to obtain a hot rolled steel plate; and
and cooling the hot-rolled steel sheet to a cooling completion temperature of the Bs temperature or lower at a cooling rate of 25 ℃/s to 50 ℃/s.
5. The method of manufacturing a low yield ratio high strength steel material according to claim 4, wherein:
the steel slab further comprises copper (Cu): 0.1 to 0.5 wt%, molybdenum (Mo): 0.15 to 0.3 wt.% and vanadium (V): 0.005 to 0.3% by weight of at least one element.
6. The method of manufacturing a low yield ratio high strength steel material according to claim 4, wherein:
the hot rolling is performed at a reduction ratio of 50% to 80%.
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| KR102255818B1 (en) * | 2019-06-24 | 2021-05-25 | 주식회사 포스코 | High strength steel for a structure having excellent corrosion resistance and manufacturing method for the same |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101289727A (en) * | 2007-04-20 | 2008-10-22 | 株式会社神户制钢所 | Low yield ratio and high tension steel plate with welding heat effect part and mother plate having excellent low temperature toughness |
| CN101665887A (en) * | 2008-09-03 | 2010-03-10 | 株式会社神户制钢所 | Thick steel board |
| WO2015079661A1 (en) * | 2013-11-28 | 2015-06-04 | Ｊｆｅスチール株式会社 | Hot-rolled steel sheet and method for manufacturing same |
Family Cites Families (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5597425A (en) | 1979-01-19 | 1980-07-24 | Nippon Kokan Kk <Nkk> | Preparation of high-tensile steel with low yield ratio, low carbon and low alloy |
| JPH0551694A (en) * | 1991-08-20 | 1993-03-02 | Nkk Corp | High tensile strength steel with low yield ratio and its production |
| KR100851189B1 (en) * | 2006-11-02 | 2008-08-08 | 주식회사 포스코 | Steel plate for linepipe having ultra-high strength and excellent low temperature toughness and manufacturing method of the same |
| JP5223375B2 (en) * | 2007-03-01 | 2013-06-26 | 新日鐵住金株式会社 | High-strength hot-rolled steel sheet for line pipe excellent in low-temperature toughness and method for producing the same |
| KR101018131B1 (en) * | 2007-11-22 | 2011-02-25 | 주식회사 포스코 | High strength and low yield ratio steel for structure having excellent low temperature toughness |
| KR101096992B1 (en) * | 2008-03-27 | 2011-12-20 | 가부시키가이샤 고베 세이코쇼 | 780MPa CLASS LOW YIELD RATIO CIRCULAR STEEL FOR CONSTRUCTION STRUCTURE EXCELLENT IN EARTHQUAKE-PROOF PERFORMANCE, AND PROCESS FOR PRODUCING THE SAME |
| KR101070132B1 (en) * | 2008-12-18 | 2011-10-05 | 주식회사 포스코 | Steel with Excellent Low-Temperature Toughness for Construction and Manufacturing Method Thereof |
| JP5776398B2 (en) * | 2011-02-24 | 2015-09-09 | Ｊｆｅスチール株式会社 | Low yield ratio high strength hot rolled steel sheet with excellent low temperature toughness and method for producing the same |
| BR112013026849B1 (en) * | 2011-04-21 | 2019-03-19 | Nippon Steel & Sumitomo Metal Corporation | HIGH RESISTANCE COLD LAMINATED STEEL PLATE HAVING EXCELLENT UNIFORM STRETCHING AND HOLE EXPANSION CAPACITY AND METHOD FOR PRODUCTION |
| KR101546124B1 (en) * | 2013-03-28 | 2015-08-20 | 현대제철 주식회사 | Hot-rolled steel and method of manufacturing the same |
| WO2014162680A1 (en) * | 2013-04-04 | 2014-10-09 | Ｊｆｅスチール株式会社 | Hot-rolled steel sheet and method for manufacturing same |
| MX2015014436A (en) * | 2013-04-15 | 2016-02-03 | Jfe Steel Corp | High-strength hot-rolled steel sheet and method for manufacturing same. |
| KR101505299B1 (en) * | 2013-06-27 | 2015-03-24 | 현대제철 주식회사 | Steel and method of manufacturing the same |
| KR101560943B1 (en) * | 2013-12-24 | 2015-10-15 | 주식회사 포스코 | Hot rolled steel sheet having a good low temperature toughness and method for manufacturing the same |
| KR101846103B1 (en) * | 2013-12-25 | 2018-04-05 | 신닛테츠스미킨 카부시키카이샤 | Electric resistance welded steel pipe for oil well |
-
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101289727A (en) * | 2007-04-20 | 2008-10-22 | 株式会社神户制钢所 | Low yield ratio and high tension steel plate with welding heat effect part and mother plate having excellent low temperature toughness |
| CN101665887A (en) * | 2008-09-03 | 2010-03-10 | 株式会社神户制钢所 | Thick steel board |
| WO2015079661A1 (en) * | 2013-11-28 | 2015-06-04 | Ｊｆｅスチール株式会社 | Hot-rolled steel sheet and method for manufacturing same |
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