CN106567011A - Easy-to-weld ultra-thick steel plate with high strength and high toughness suitable for minus 60 DEG C and manufacturing method thereof - Google Patents
Easy-to-weld ultra-thick steel plate with high strength and high toughness suitable for minus 60 DEG C and manufacturing method thereof Download PDFInfo
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- CN106567011A CN106567011A CN201610984842.4A CN201610984842A CN106567011A CN 106567011 A CN106567011 A CN 106567011A CN 201610984842 A CN201610984842 A CN 201610984842A CN 106567011 A CN106567011 A CN 106567011A
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 102
- 239000010959 steel Substances 0.000 title claims abstract description 102
- 238000004519 manufacturing process Methods 0.000 title claims description 29
- 238000009749 continuous casting Methods 0.000 claims abstract description 20
- 238000010791 quenching Methods 0.000 claims abstract description 19
- 230000000171 quenching effect Effects 0.000 claims abstract description 18
- 238000005096 rolling process Methods 0.000 claims abstract description 17
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 15
- 238000010583 slow cooling Methods 0.000 claims abstract description 14
- 238000005496 tempering Methods 0.000 claims abstract description 12
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000000126 substance Substances 0.000 claims abstract description 6
- 238000003723 Smelting Methods 0.000 claims abstract description 4
- 238000007670 refining Methods 0.000 claims abstract description 3
- 238000000034 method Methods 0.000 claims description 34
- 230000008569 process Effects 0.000 claims description 16
- 239000000203 mixture Substances 0.000 claims description 11
- 238000003466 welding Methods 0.000 claims description 11
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 8
- 230000009467 reduction Effects 0.000 claims description 6
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 5
- 229910052739 hydrogen Inorganic materials 0.000 claims description 5
- 239000001257 hydrogen Substances 0.000 claims description 5
- 230000014759 maintenance of location Effects 0.000 claims description 5
- 229910052717 sulfur Inorganic materials 0.000 claims description 5
- 238000005516 engineering process Methods 0.000 claims description 4
- 229910052742 iron Inorganic materials 0.000 claims description 4
- 230000035945 sensitivity Effects 0.000 claims description 4
- 238000001816 cooling Methods 0.000 claims description 3
- 229910052802 copper Inorganic materials 0.000 claims description 3
- 229910052757 nitrogen Inorganic materials 0.000 claims description 3
- 229910052698 phosphorus Inorganic materials 0.000 claims description 3
- 238000005275 alloying Methods 0.000 claims description 2
- 229910001563 bainite Inorganic materials 0.000 claims description 2
- 229910052804 chromium Inorganic materials 0.000 claims description 2
- 229910052748 manganese Inorganic materials 0.000 claims description 2
- 229910052750 molybdenum Inorganic materials 0.000 claims description 2
- 229910052759 nickel Inorganic materials 0.000 claims description 2
- 229910052758 niobium Inorganic materials 0.000 claims description 2
- 239000006104 solid solution Substances 0.000 claims description 2
- 238000009628 steelmaking Methods 0.000 claims description 2
- 238000003860 storage Methods 0.000 claims description 2
- 229910052720 vanadium Inorganic materials 0.000 claims description 2
- 229910000859 α-Fe Inorganic materials 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 abstract description 4
- 239000004615 ingredient Substances 0.000 abstract description 3
- 238000005266 casting Methods 0.000 abstract 1
- 238000009847 ladle furnace Methods 0.000 abstract 1
- 239000002184 metal Substances 0.000 abstract 1
- 238000009849 vacuum degassing Methods 0.000 abstract 1
- 239000010949 copper Substances 0.000 description 6
- 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 5
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 229910001566 austenite Inorganic materials 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 230000007812 deficiency Effects 0.000 description 2
- 239000003607 modifier Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000005728 strengthening Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 208000031481 Pathologic Constriction Diseases 0.000 description 1
- 208000037656 Respiratory Sounds Diseases 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000004568 cement Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 210000001215 vagina Anatomy 0.000 description 1
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
- C22C38/18—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
-
- 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
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
-
- 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
- C21D8/0257—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment with diffusion of elements, e.g. decarburising, nitriding
-
- 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
- C22C38/18—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
-
- 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
-
- 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
-
- 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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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
Abstract
The invention relates to an easy-to-weld ultra-thick steel plate with high strength and high toughness suitable for minus 60 DEG C. The steel plate comprises the chemical ingredients of 0.05% to 0.10% of C, 0.2% to 0.3% of Si, 1.3% to 1.6% of Mn, 0.02% to 0.04% of Al, 0.03% to 0.05% of Nb, 0.03 to 0.05% of V, 0.1% to 0.3% of Cr, 0.1% to 0.4% of Ni, 0.1% to 0.3% of Mo, 0.1% to 0.3% of Cu, 0.01% to 0.02% of Ti, 0% to 0.015% of P, 0% to 0.002% of S, and 0% to 0.007% of N; the carbon equivalent is not larger than 0.43, and Pcm is not larger than 0.20. According to the steel plate, the thickness ranges from 70 mm to 120 mm, the yield strength is 460 MPa or more, and under the temperature of minus 60 DEG C, both the Charpy impact energy at the position, with the thickness one quarter that of the thickness of the steel plate, of the steel plate and the Charpy impact energy at the position, with the thickness one half that of the thickness of the steel plate, of the steel plate are larger than or equal to 100 J. The easy-to-weld ultra-thick steel plate with high strength and high toughness is made through the steps of KR hot metal pretreatment, converter smelting, ladle furnace refining, RH vacuum degassing, continuous casting, slow cooling, casting blank heating, rolling, straightening, pile slow cooling, quenching, tempering and the like.
Description
Technical field
The invention belongs to low temperature special steel plate manufacture field, and in particular to a kind of to be served under -60 DEG C of environment
460MPa levels easily weld high-strength and high-ductility super-thick steel plate.
Background technology
With the continuous rising of structure hardness of steel, 460MPa low-alloy high-strength steel plates have become most important engineering knot
One of structure material, is widely used in the great work such as ocean engineering, shipbuilding, high building structure, bridge, track traffic, automobile making
Cheng Zhong.Currently, in addition to requiring the requirement that steel plate meets intensity, according to different use environments, especially severe cold areas, to low
Warm toughness, the weldability of material have more stringent requirement.Require -60 DEG C at Charpy-V impact power in more than 100J, while C contains
Amount is below 0.10%.At present, the 70-120mm thickness 460MPa used at -60 DEG C can be met using hardening and tempering process production easy
Welding high-strength and high-ductility super-thick steel plate yet there are no at home the report of commercialization manufacture.
The manufacture method of domestic 460MPa ranks low-alloy high-strength steel plate is broadly divided into two big class, and a class is TMCP techniques
Manufacture.Advantage is that weldability is good, low cost；Have the disadvantage that internal stress is big, lack of homogeneity, performance inconsistency is big.Patent announcement CN
The patent of invention of 103320692A proposes a kind of superhigh tenacity, superior weldability HT550 steel plates and its manufacture method, adopts
Ultra-low carbon composition design, the manufacture of TMCP+ Self-temperings, -60 DEG C of ballistic work >=60J, maximum gauge 100mm.Patent announcement number
The patent of invention of CN 103938108A proposes a kind of 460MPa low compression ratios high-tenacity steel plate for ocean engineering and its manufacture
Method, using low-carbon (LC)（C0.04-0.07%）+ microalloying ingredient is designed, the design of TMCP+ tempering process, can produce maximum gauge
The 460MPa high-strength and high-ductilities of -60 DEG C of ballistic work >=240J of satisfaction of 80mm easily weld extra large work steel, at present, are not yet related to
120mm thickness steel plates are reported.The patent of invention of patent announcement CN104264047A proposes a kind of container of 70mm thickness
With the manufacture method of super-thick steel plate, using low-carbon (LC) C：0.04-0.12% microalloy composition designs, TMCP techniques produce -40 DEG C of bars
The 70mm thickness 460MPa level container super-thick steel plates used under part.Other are such as patent publication No. CN104313468, CN
105112806、CN 101649420、CN 101318287 CN 101403075、CN 101775552、CN 102782751、CN
102644024th, CN 103866188 adopts low-carbon (LC)+TMCP technique productions 460MPa steel, thickness specification maximum to be less than
100mm。
An other class is manufactured using normalizing process.Advantage is that stability is good, and thickness is big, has the disadvantage that C content is high, low
Warm toughness and weldability are poor.Patent announcement CN 104805374A propose a kind of Q460E of thickness more than 120mm thickness
Steel plate and its manufacture method, using C：0.15-0.19% adds microalloy composition design, normalizing process production, maximum gauge to be related to
130mm, can use under the conditions of -40 DEG C, -40 DEG C of ballistic work >=100J.Patent announcement CN 104726773A propose a kind of
Normalizing type high-strength pressure vessel steel plate with -50 DEG C of good low-temperature impact toughness, using C0.10-0.22% plus microalloy
Composition design, normalizing process production, thickness reaches 80mm, yield strength >=460MPa, -60 DEG C of ballistic work >=100J.Patent is public
The A of announcement CN 104846277 propose a kind of high building structure steel of the anti-lamellar tearing performance of yield strength >=460MPa
And manufacture method, being designed using C0.15-0.18% plus microalloying ingredient, production 80-100mm is thick for normalizing+accelerated cooling process
Degree Steels for High Rise Buildings, -20 DEG C of ballistic work >=80J.Other are such as patent announcement CN 105525209, CN 101613828, CN
102719737 produce 460MPa grade high-strength steel using normalizing process, and C content is more than 0.10%.
The country also has partial monopoly to produce 460MPa level steel plates using hardening and tempering process, and patent No. CN 104894490A's sends out
Bright patent proposes high strength special heavy plate and its manufacture method, is produced using hardening and tempering process, and maximum gauge reaches 266mm, by force
Degree is in more than 460MPa, but C content is in 0.12-0.14%, while only meeting -20 DEG C of ballistic work ﹥ 27J.It is unsatisfactory for easy weldability
（C content≤0.10%）With the condition used under -60 DEG C of cryogenic conditions.
The content of the invention
The technical problem to be solved is to provide one kind for above-mentioned prior art to use under the conditions of -60 DEG C
70-120mm thickness, carbon equivalent≤0.43, cold crack sensitivity coefficient（Pcm）≤ 0.20 460MPa easily welds high-strength and high-ductility
Super-thick steel plate and its manufacture method.
The present invention the adopted technical scheme that solves the above problems is：A kind of easy welding high-strength and high ductility suitable for -60 DEG C
Property super-thick steel plate, the chemical composition mass percent of the steel plate is C 0.05-0.10%, Si 0.2-0.3%, Mn 1.3-1.6%,
Al 0.02-0.04%, Nb 0.03-0.05%, V 0.03-0.05%, Cr 0.1-0.3%, Ni 0.1-0.4%, Mo 0.1-0.3%,
Cu 0.1-0.3%, Ti 0.01-0.02%, P≤0.015%, S≤0.002%, N≤0.007%, carbon equivalent≤0.43, welding is split
Stricture of vagina sensitivity coefficient Pcm=C+Si/30+ (Mn+Cu+Cr)/20+Ni/60+Mo/15+V/10+5B≤0.20.
The thickness of steel plate of the present invention be 70-120mm, yield strength 460MPa and more than, tensile strength 570-720MPa is prolonged
Stretch rate >=17%, at -60 DEG C of thickness of lower steel plate 1/4 and 1/2 thickness Charpy-V impact power >=100J, meet -60 DEG C of conditions and use.
Lower carbon content design is this invention takes, so as to obtain lower carbon equivalent and crack-sensitivity coefficient, to protect
The weldability of card steel plate.
The effect of contained all components and its content select reason to be described as follows in the present invention：
C：The essential element of intensity, quenching degree and weldability is affected, from the angle of weldability, C content will be less than 0.10%, from quenching
Permeability and the angle of reinforcing, the higher the better for C.Consider, the C content range of choice of the present invention is 0.05-0.10%.
Si：Deoxidant element, with the intensity that solution strengthening form improves steel, too high meeting Surface Quality, toughness and weldability
Can have a negative impact, it is too low, deoxidation effect is affected, consider, the Si contents of the present invention range of choice is 0.2-0.4%.
Mn：With the intensity that solution strengthening form improves steel, making up C reduces and caused deficiency；Affect intensity, quenching degree and
The main alloy element of weldability, C content is relatively low in this composition, needs the invigoration effect for preferably playing Mn.Consider, this
The range of choice of invention Mn contents is 1.30-1.60%.
Al：Deoxidant element, and play a part of crystal grain thinning by forming AlN.The range of choice of Al content of the present invention is
0.02-0.04%。
Nb：Unhydrated cement temperature is improved, fining austenite grains are conducive to the raising of intensity and toughness.Nb of the present invention
The range of choice of content is 0.03-0.05%.
V：Carbonitride-forming elements, form V（C, N）, the intensity and toughness of steel, refinement are improved in the form of dispersion-strengtherning
Crystal grain.The range of choice of V content of the present invention is 0.03-0.05%.
Cr：The quenching degree and intensity of steel are improved, the relatively low deficiency for causing intensity and quenching degree to decline of C content is made up.It is excessive,
Then the low-temperature impact toughness of steel and weldability can be had a negative impact.The range of choice of Cr contents of the present invention is 0.1-0.3%.
Ni：The quenching degree of steel plate can be improved, while improving the intensity of steel and improving low-temperature impact toughness, is contained in Cu elements
Improve the hot cracking tendency of material when measuring too high.During Ni too high levels, the higher oxygen of viscosity can be produced in continuous casting billet heating process
Change iron sheet, affect plate surface quality.Meanwhile, excessive Ni improves the carbon equivalent and crack-sensitivity coefficient of steel plate, lifts manufacture
Cost, affects the weldability of steel plate.The range of choice of Ni contents of the present invention is 0.1-0.4%.
Mo：Ferritic transformation is postponed, the quenching degree of steel is significantly improved, steel returns when appropriate Mo can overcome modifier treatment
Fiery fragility is so as to improving the impact flexibility of steel.The range of choice of Mo contents of the present invention is 0.1-0.3%.
Cu：Austenite stabilizer element, it is possible to increase the quenching degree of steel, intensity and decay resistance, reduces the hydrogen of steel plate
Cause crack sensitivity；Also the weldability of steel plate can be had a negative impact simultaneously, while needing to add more Ni to avoid producing
The crisp phenomenon of the pig copper.The range of choice of Cu contents of the present invention is 0.1-0.3%.
Ti：Play a part of precipitation strength, effective crystal grain thinning by forming TiN.The range of choice of Ti contents of the present invention
For 0.01-0.02%.
P、S：As the major impurity element in steel, the low-temperature impact toughness of steel plate especially steel plate center portion can be produced not
Profit affects, and it is more low better to control.According to existing actual production conditions, the range of choice of P, S content of the present invention is P≤0.015%, S
≤0.002%。
Suitable for -60 DEG C of easy welding high-strength and high-ductility super-thick steel plate, it is characterised in that：The thickness of steel plate is 70-
120mm, yield strength 460MPa and more than, tensile strength 570-720MPa, elongation percentage >=17%, -60 DEG C of thickness of lower steel plate 1/4
>=100J equal with Charpy-V impact power at 1/2 thickness, meets -60 DEG C of conditions and uses.
The manufacture method of the above-mentioned easy welding high-strength and high-ductility super-thick steel plate suitable for -60 DEG C, step is as follows
（1）In steel making working procedure, produced using KR molten iron pretreatment, converter smelting, LF refining, RH Fruit storages high-purity
Net molten steel, then produces 300-450mm thickness continuous casting plate billets by special thickness continuous casting steel billet production technology, and continuous casting billet is carried out to add
Cover stacking slow cooling expands hydrogen and processes, stacking slow cooling time >=120 hour；
（2）Continuous casting billet is heated to into 1150-1250 DEG C, 160-180min is incubated, the abundant solid solution of the alloying element in steel is made to protect
The uniformity of card performance, continuous casting billet uses high-pressure water descaling after coming out of the stove；
（3）Jing after high-pressure water descaling, continuous casting billet is carried out into two-phase control rolling, the first stage is roughing, and start rolling temperature is in 1100-
1160 DEG C, average reduction ratio >=14% of single pass；Second stage is finish rolling, and start rolling temperature is 820-880 DEG C, adds up passage pressure
Rate >=40%；Thermal straightening is carried out after rolling；
（4）Steel plate carries out offline heap slow cooling expansion hydrogen process after thermal straightening, reduces the content of H in steel plate to ensure steel plate center portion low temperature
Impact flexibility, heap temperature retention time >=48 hour；
（5）Quenching+tempering process is carried out to the steel plate after slow cooling, quenching and tempering are carried out in continuous oven, and hardening heat is
890-910 DEG C, time inside furnace 1.8-2.0min/mm；Temperature is 630-680 DEG C, and time inside furnace 3.5-4.0min/mm goes out
Furnace rear air cooling.
The present invention for the easy welding high-strength and high-ductility steel plate that uses under the conditions of -60 DEG C, using low-carbon (LC), low-carbon-equivalent and
Low crack-sensitivity coefficient contribution design, the smelting of high purity steel, the special thickness continuous casting steel billet of 300-450mm thickness are taken as raw material
Controlled rolling adds the method for modifier treatment to produce 70-120mm thickness 460MPa easily to weld high-strength and high-ductility steel plate, and steel plate is most
Whole metallographic structure is ferrite bainite tissue.
The present invention adopts low-carbon (LC), low-carbon-equivalent and low-crackle sensitive composition design, to ensure the weldability of steel plate, its
C0.05-0.10%, carbon equivalent≤0.43, crack-sensitivity FACTOR P cm≤0.20；It is simultaneously thick using hardening and tempering process production 70-120mm
Degree 460MPa ranks use steel super-thick steel plate under the conditions of can meeting -60 DEG C.According to the steel plate of present invention production, with good
On the basis of weldability, with excellent high-strength and high-ductility, yield strength >=460MPa, tensile strength between 570-720MPa,
Elongation percentage >=17%, at 1/4 thickness and 1/2 thickness of -60 DEG C of lower steel plates Charpy-V impact power >=100J, disclosure satisfy that at -60 DEG C
Cryogenic conditions under use.
Description of the drawings
Fig. 1 is the microstructure picture of the 70mm thickness steel plates of the embodiment of the present invention 1；
Fig. 2 is the microstructure picture of the 120mm thickness steel plates of the embodiment of the present invention 2.
Specific embodiment
The present invention is described in further detail below in conjunction with accompanying drawing embodiment.
Chemical composition ranges of the invention and manufacture method, Jing KR molten iron pretreatment-converter smelting-LF refining-
RH vacuum outgass-continuous casting-continuous casting billet covering slow cooling-continuous casting billet inspection cleaning-heating strand-high-pressure water descaling-rolls
The processing steps such as system-aligning-steel plate heap slow cooling-quenching-tempering, manufacture the 460MPa high-strength and high-ductilities of thickness 70-120mm
Easy welding steel.
Continuous casting billet stacking covering slow cooling more than 120 hours.
The concrete technology of above-mentioned heating, rolling and slow cooling stage is：370mm thickness continuous casting billets are heated to into 1230 DEG C, are protected
Warm 180min（Embodiment 1,2）, continuous casting billet come out of the stove after use high-pressure water descaling；Then two-phase control rolling is carried out, the first stage opens
Roll 1100 DEG C of temperature（Embodiment 1）Or 1150 DEG C（Embodiment 2）, workpiece thickness 200mm, the average reduction ratio 16% of single pass；The
Two-stage start rolling temperature is 840 DEG C, adds up percentage pass reduction 65%（Embodiment 1）Or 830 DEG C of second stage start rolling temperature, add up
Percentage pass reduction 40%（Embodiment 2）, final steel plate thickness is 70mm（Embodiment 1）And 120mm（Embodiment 2）.Heat is rectified after rolling
Directly；Steel plate carries out offline heap slow cooling, heap temperature retention time 48 hours after thermal straightening（Embodiment 1）With 72 hours（Embodiment 2）.
Steel plate after the completion of slow cooling carries out Quenching Treatment into continuous oven.Embodiment 1：890 DEG C of heating-up temperature, time inside furnace
1.8min/mm, using quenching press water quenching.Embodiment 2：910 DEG C of heating-up temperature, time inside furnace 2.0min/mm, using quenching press water
Quench.Steel plate to completing Quenching Treatment carries out temper in continuous oven.Embodiment 1:630 DEG C of heating-up temperature, time inside furnace
4.0min/mm, embodiment 2：660 DEG C of heating-up temperature, time inside furnace 4.0min/mm.
Steel plate chemical composition obtained in embodiment 1 and 2 is shown in Table 1, and the mechanical property of steel plate is shown in Table 2, the microscopic structure of steel plate
As depicted in figs. 1 and 2.
The chemical composition of the anti-lamellar tearing steel plate of high-strength and high-ductility is easily welded in the embodiment 1 and 2 of table 1（wt.%）
Ceq=C+Mn/6+（Cr+Mo+V）/5+（Ni+Cu）/15
Pcm=C+Si/30+(Mn+Cu+Cr)/20+Ni/60+Mo/15+V/10+5B
The mechanical property of the anti-lamellar tearing steel plate of high-strength and high-ductility is easily welded in the embodiment 1 and 2 of table 2
In addition to the implementation, present invention additionally comprises there is other embodiment, all employing equivalents or equivalence replacement mode
The technical scheme of formation, all should fall within the scope of the hereto appended claims.
Claims (3)
1. a kind of easy welding high-strength and high-ductility super-thick steel plate suitable for -60 DEG C, it is characterised in that：The chemical composition matter of the steel plate
Amount percentage ratio is C 0.05-0.10%, Si 0.2-0.3%, Mn 1.3-1.6%, Al 0.02-0.04%, Nb 0.03-0.05%, V
0.03-0.05%, Cr 0.1-0.3%, Ni 0.1-0.4%, Mo 0.1-0.3%, Cu 0.1-0.3%, Ti 0.01-0.02%, P≤
0.015%, S≤0.002%, N≤0.007%, carbon equivalent≤0.43, weld crack sensitivity coefficient Pcm=C+Si/30+ (Mn+Cu+
Cr)/20+Ni/60+Mo/15+V/10+5B≤0.20。
2. the easy welding high-strength and high-ductility super-thick steel plate suitable for -60 DEG C according to claim 1, it is characterised in that：Steel
The thickness of plate be 70-120mm, yield strength 460MPa and more than, tensile strength 570-720MPa, elongation percentage >=17%, -60 DEG C
At the thickness of lower steel plate 1/4 and 1/2 thickness Charpy-V impact power >=100J, meet -60 DEG C of conditions and use, the metallographic group of steel plate finished product
It is woven to ferrite bainite tissue.
3. the manufacture method of the easy welding high-strength and high-ductility super-thick steel plate suitable for -60 DEG C according to claim 1 and 2,
It is characterized in that：Step is as follows
In steel making working procedure, high-purity is produced using KR molten iron pretreatment, converter smelting, LF refining, RH Fruit storages
Molten steel, then produces 300-450mm thickness continuous casting plate billets by special thickness continuous casting steel billet production technology, and to continuous casting billet covering is carried out
Stacking slow cooling expands hydrogen and processes, stacking slow cooling time >=72 hour；
Continuous casting billet is heated to into 1150-1250 DEG C, 160-180min is incubated, the abundant solid solution of the alloying element in steel is made with guarantee property
The uniformity of energy, continuous casting billet uses high-pressure water descaling after coming out of the stove；
Jing after high-pressure water descaling, continuous casting billet is carried out into two-phase control rolling, the first stage is roughing, and start rolling temperature is in 1100-1160
DEG C, average reduction ratio >=14% of single pass；Second stage is finish rolling, and start rolling temperature is 820-880 DEG C, accumulative percentage pass reduction >=
40%；Thermal straightening is carried out after rolling；
Steel plate carries out offline heap slow cooling expansion hydrogen process after thermal straightening, and the content for reducing H in steel plate is rushed with ensureing steel plate center portion low temperature
Hit toughness, heap temperature retention time >=48 hour；
Quenching+tempering process is carried out to the steel plate after slow cooling, quenching and tempering are carried out in continuous oven, and hardening heat is 890-
910 DEG C, time inside furnace 1.8-2.0min/mm；Temperature is 630-680 DEG C, time inside furnace 3.5-4.0min/mm, after coming out of the stove
Air cooling.
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