CN100436632C - Vanadium treated bake hardening type deep drew steel plates of saloon sedan, and preparation method - Google Patents
Vanadium treated bake hardening type deep drew steel plates of saloon sedan, and preparation method Download PDFInfo
- Publication number
- CN100436632C CN100436632C CNB2006101250029A CN200610125002A CN100436632C CN 100436632 C CN100436632 C CN 100436632C CN B2006101250029 A CNB2006101250029 A CN B2006101250029A CN 200610125002 A CN200610125002 A CN 200610125002A CN 100436632 C CN100436632 C CN 100436632C
- Authority
- CN
- China
- Prior art keywords
- steel
- temperature
- rolling
- saloon
- sedan
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 131
- 239000010959 steel Substances 0.000 title claims abstract description 131
- 229910052720 vanadium Inorganic materials 0.000 title claims abstract description 37
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 title claims description 25
- 238000002360 preparation method Methods 0.000 title claims description 12
- 238000000137 annealing Methods 0.000 claims abstract description 47
- 238000005096 rolling process Methods 0.000 claims abstract description 35
- 238000000034 method Methods 0.000 claims abstract description 23
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 23
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 15
- 238000005097 cold rolling Methods 0.000 claims abstract description 11
- 238000010438 heat treatment Methods 0.000 claims abstract description 10
- 229910052698 phosphorus Inorganic materials 0.000 claims abstract description 10
- 229910052748 manganese Inorganic materials 0.000 claims abstract description 8
- 229910052717 sulfur Inorganic materials 0.000 claims abstract description 8
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 6
- 239000000126 substance Substances 0.000 claims description 16
- 230000008569 process Effects 0.000 claims description 14
- 238000005516 engineering process Methods 0.000 claims description 12
- 239000000203 mixture Substances 0.000 claims description 12
- 238000005098 hot rolling Methods 0.000 claims description 11
- 229910052742 iron Inorganic materials 0.000 claims description 7
- 238000009628 steelmaking Methods 0.000 claims description 5
- 238000005728 strengthening Methods 0.000 claims description 5
- 230000015572 biosynthetic process Effects 0.000 claims description 3
- 238000005482 strain hardening Methods 0.000 claims description 3
- 229910052782 aluminium Inorganic materials 0.000 abstract description 11
- 238000001816 cooling Methods 0.000 abstract description 8
- 238000004080 punching Methods 0.000 abstract description 5
- 238000005265 energy consumption Methods 0.000 abstract 1
- 229910052799 carbon Inorganic materials 0.000 description 53
- 239000010936 titanium Substances 0.000 description 36
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 32
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 19
- 239000006104 solid solution Substances 0.000 description 18
- 238000004519 manufacturing process Methods 0.000 description 16
- 150000001721 carbon Chemical group 0.000 description 13
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 12
- 239000013078 crystal Substances 0.000 description 12
- 239000011572 manganese Substances 0.000 description 11
- 239000010955 niobium Substances 0.000 description 11
- 239000000047 product Substances 0.000 description 10
- 229910000859 α-Fe Inorganic materials 0.000 description 10
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 9
- 239000004615 ingredient Substances 0.000 description 9
- 229910052758 niobium Inorganic materials 0.000 description 9
- 238000001953 recrystallisation Methods 0.000 description 8
- 230000000694 effects Effects 0.000 description 7
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 6
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 6
- 239000004411 aluminium Substances 0.000 description 6
- 238000013461 design Methods 0.000 description 6
- 238000009792 diffusion process Methods 0.000 description 6
- 239000011159 matrix material Substances 0.000 description 6
- 238000012545 processing Methods 0.000 description 6
- 239000002893 slag Substances 0.000 description 6
- 241001062472 Stokellia anisodon Species 0.000 description 5
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 4
- 239000005864 Sulphur Substances 0.000 description 4
- 125000004429 atom Chemical group 0.000 description 4
- 230000003993 interaction Effects 0.000 description 4
- 238000005554 pickling Methods 0.000 description 4
- 238000007670 refining Methods 0.000 description 4
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 3
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 3
- 230000032683 aging Effects 0.000 description 3
- 229910052786 argon Inorganic materials 0.000 description 3
- 229910001566 austenite Inorganic materials 0.000 description 3
- 238000007664 blowing Methods 0.000 description 3
- 238000005266 casting Methods 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 238000005261 decarburization Methods 0.000 description 3
- 238000007872 degassing Methods 0.000 description 3
- 238000006392 deoxygenation reaction Methods 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 235000019362 perlite Nutrition 0.000 description 3
- 239000010451 perlite Substances 0.000 description 3
- 239000011574 phosphorus Substances 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- 238000002203 pretreatment Methods 0.000 description 3
- 230000001681 protective effect Effects 0.000 description 3
- 230000035882 stress Effects 0.000 description 3
- 238000009966 trimming Methods 0.000 description 3
- 238000003723 Smelting Methods 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000009749 continuous casting Methods 0.000 description 2
- 230000002950 deficient Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 230000000630 rising effect Effects 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 241000167854 Bourreria succulenta Species 0.000 description 1
- 241000196324 Embryophyta Species 0.000 description 1
- 229910000742 Microalloyed steel Inorganic materials 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 230000002776 aggregation 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
- 230000004888 barrier function Effects 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- 229910001567 cementite Inorganic materials 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 235000019693 cherries Nutrition 0.000 description 1
- 230000003749 cleanliness Effects 0.000 description 1
- 230000001427 coherent effect Effects 0.000 description 1
- 239000010960 cold rolled steel Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- KSOKAHYVTMZFBJ-UHFFFAOYSA-N iron;methane Chemical compound C.[Fe].[Fe].[Fe] KSOKAHYVTMZFBJ-UHFFFAOYSA-N 0.000 description 1
- 208000020442 loss of weight Diseases 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 1
- 150000004767 nitrides Chemical class 0.000 description 1
- 229910017464 nitrogen compound Inorganic materials 0.000 description 1
- 150000002830 nitrogen compounds Chemical class 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229920001296 polysiloxane Polymers 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000004881 precipitation hardening Methods 0.000 description 1
- 238000004886 process control Methods 0.000 description 1
- 230000035755 proliferation Effects 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- CADICXFYUNYKGD-UHFFFAOYSA-N sulfanylidenemanganese Chemical compound [Mn]=S CADICXFYUNYKGD-UHFFFAOYSA-N 0.000 description 1
- 150000004763 sulfides Chemical class 0.000 description 1
- 230000000930 thermomechanical effect Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
Images
Landscapes
- Heat Treatment Of Sheet Steel (AREA)
Abstract
This invention relates to a method for preparing sclerous and deeply punched steel boards used in saloon cars. The steel boards comprises: C less than or equal to 0.005%, Si less than or equal to 0.030%, Mn 0.10-0.40%, P 0.02-0.08%, S less than or equal to 0.015%, Ti 0.01-0.04%, Al 0.01-0.07%, V 0.020-0.070% and N less than or equal to 0.004%. Heat-rolling parameters are: heating temperature of raw steel 1200 plus and minus 39 deg.C; temperature difference of steel boards less than or equal to 25 deg.C; firstly rolling exit temperature 1080 plus and minus 20 deg.C; refining-rolling entrance temperature 1040 plus and minus 20 deg.C; final rolling temperature 900 plus and minus 20 deg.C; cooling rate 10-30 deg.C/s; rolling temperature 700 plus and minus 20 deg.C. Cold-rolling parameters are: total press rate 75-80%; annealing temperature 820-850 deg.C; stretching rate 0.9-1.5%. The steel boards have such advantages as high strength, high punching performance, high concave resistance, low weight and low energy consumption, and are environmentally friendly.
Description
Technical field
The present invention relates to a kind of steel plate and manufacture method thereof, specifically a kind of vanadium treated bake hardening type deep drew steel plates of saloon sedan and preparation method.
Background technology
Super deep-draw BH steel is a kind of new automobile plate that utilizes the strain aging acquisition car panel dent resistance energy of gap solid solution atom (mostly being the C atom), its technology difficulties is stable higher BH value and the good deep drawability of obtaining, and inherent mechanism is that the control of solid solution C content must accurately and suit; In addition, the yield point elongation problem of BH steel plate also is a control difficult problem.
The external at present following 3 kinds of methods control of the many employings of this steel plate solid solution C that produces: 1. keep the C equivalent and surpass Ti and Nb equivalent in the steel-making stage; 2. be completely fixed C in the hot rolling stage with Ti or Nb, with high temperature annealing C existed in company's stage of moving back with the sosoloid form then; The mean method of 3. preceding two kinds of schemes.1. Nippon Steel's employing method accurately controls C, Ti, Nb content in steelmaking process, the Nb/C atomic ratio is controlled at about 0.9, successfully develops the BH steel plate of good forming ability; 2. exploitation new BH auto sheet in Kawasaki Steel then adopts method, makes the ultra low-carbon steel that contains Ti, Nb all not have solid solution C in hot rolling, cold rolling stage and exists, and carries out high temperature annealing under the recrystallization temperature being higher than, and makes the carbide dissolving, obtains the solid solution C of some amount.Current super deep-draw BH steel plate production technology principle of generally acknowledging in the world is that the continuous annealing production line that can carry out high temperature annealing about 850～900 ℃ must be arranged, the production equipment that comprises many countries of China does not all reach processing requirement, and this is the weakness place of the super deep-draw BH of China's domestic-developed auto sheet just.Many for many years investigators solve this technical barrier in the searching way.
Through experimental study, the contriver finds to adopt the design of vanadium processing Ultra-low carbon BH steel to help to capture this production technique difficult problem.Owing to VC phase solid solution equilibrium temperature is low far beyond NbC,,, produce the BH auto sheet that has the excellent deep drawability dent resistance energy stable concurrently with height by suitable chemical ingredients and rolling technology design so cold rolling mill has now under the annealing device condition at home.
Vanadium is handled ultra-low carbon baking hardening steel plate at present in the domestic blank that still belongs to of China; Germany, the U.S., Britain (Holland) iron and steel enterprise are all actively developing this product, and this material is expected to be used in enormous quantities the manufacturing that car covers part outward in the future.
Summary of the invention
The object of the invention is exactly the defective that exists at prior art, by suitable chemical ingredients and rolling technology design, provides a kind of vanadium treated bake hardening type deep drew steel plates of saloon sedan, and this steel plate has high strength, good deep drawability and high dent resistance energy.
Another object of the present invention just provides the preparation method of this steel plate.
Technical scheme of the present invention is achieved in that its chemical ingredients is:
C≤0.005%, Si≤0.030%, Mn 0.10～0.40%, and P 0.02～0.08%, S＜0.015%, Ti 0.01～0.04%, and Als 0.01～0.07%, and V 0.020～0.070%, N≤0.004%, all the other are Fe; Als represents sour molten aluminium.
The thickness of steel plate of the present invention is 0.50～2.0mm.Described steel plate is perpendicular to rolling direction: yield strength 〉=210MPa, tensile strength 〉=340MPa, plastic strain ratio r
90〉=1.8, work hardening exponent n
90〉=0.20, unit elongation A
80mm〉=38%, BH value 〉=30MPa.
The key problem in technology point of composition of the present invention and technological design is as follows:
1. composition is to the ultra-low carbon baking hardening steel Effect on Performance
The physical substance of the baking hardening phenomenon of steel is the assembly of solid solution carbon and precipitate fault on the throne thereof in the steel, the pinned result of mobile dislocation that prestrain is produced.The baking hardenability of ultra-low carbon baking hardening steel plate comes down to the macroscopic view reflection that the solid solution carbon atom exists.The size of cold rolling production board baking hardening value depends on the quantity of solid solution carbon atom in the steel; Under the identical anneal processes condition, the steel matrix carbon concentration higher than carbon content owing to the low steel of carbon content is low, and difficulty is separated out, and has higher solid solution carbon amount after the annealing, thereby obtains higher BH value.
The intensity of test steel plate is relevant with the grain structure state with phosphorus content with the plasticity variation.Phosphorus content is many more, and the solution strengthening effect is big more, makes the influence of plasticity variation also strong more.Crystal grain is tiny more and inhomogeneous more, and then the trend that intensity increases and plasticity weakens is strong more.
Amount of carbon atom is many more in the steel plate, and then the BH value is high more.
It is vital in the production steel process of the present invention chemical ingredients carefully being designed.
Carbon (C): C is a strengthening element the most general in the steel, and carbon increases armor plate strength, and plasticity reduces.For the impact briquetting steel, what need is low yield strength, high unit elongation, and for example the carbon content of general punching press steel plate is C≤0.08% (as the 08Al steel of China); And along with the reduction of carbon content in the steel, every processability index of steel plate improves rapidly; Therefore in steel of the present invention, generally control carbon content≤0.005%.
Silicon (Si): Si also uses as a kind of strengthening element in some ultra low-carbon steel.But how bake hardening deep-draw autobody sheet is as covering part outward, and surface quality requires very high, if silicone content is higher, is difficult to remove removing iron scale, plate surface quality variation during the hot-rolled sheet pickling; And add Si and make steel plate toughness variation, so steel of the present invention does not adopt the Si reinforcement.
Phosphorus (P): P is a kind of effective element that improves armor plate strength, but can increase steel plate fragility.Steel of the present invention adopts an amount of P to strengthen, and control P is 0.02～0.08% during smelting.
Sulphur (S): S is harmful element in deep drawing steel, forms MnS, TiS sulfides in steel, should remove as far as possible; Therefore control sulphur content＜0.015%.
Aluminium (Al): Al adds as reductor in deep drawing steel, and purpose mainly is to remove the oxygen that is dissolved in when smelting in the molten steel.Aluminium can suppress the solid solution of nitrogen in ferrite as deciding the nitrogen agent in addition, eliminates strain aging, improves low-temperature flexibility.Steel control Al content of the present invention is 0.01～0.07%.
Nitrogen (N): N makes yield strength and tensile strength increase in steel, and hardness value rises, and processability descends; For the deep-draw steel, an important baneful influence of nitrogen is to cause steel plate surrender effect and strain aging.In addition, N content increases, if metallurgical technology control is improper, N is easy to form with Ti, Al etc. the inclusion of band corner angle, and is totally unfavorable for punching performance, so punching press always will reduce nitrogen as much as possible with steel, controls nitrogen content≤0.004% in the general deep drawing sheet steel.
For improving the steel plate deep drawability, reach near gap-free atom (IF) state, palpus fixation of C, N interstitial atom, steel of the present invention adopt the compound interpolation of Ti, V to handle.
Titanium (Ti): Ti can combine with N in strand, forms stable TiN particle, thereby removes the interstitial atom N in the steel; And in the hot-rolled steel sheet of controlled rolling and controlled cooling, but add 0.02% titanium crystal grain thinning, improve the yield strength and the toughness of steel, the improvement of this performance is main to improve the recrystallization temperature and the AUSTENITE GRAIN COARSENING temperature of steel with titanium, thereby it is relevant with the grain-size in the heat-processed to control continuous casting; On the other hand,, can generate hard sulphur titaniferous compound, prevent the detrimentally affect of the manganese sulfide that extends because titanium and sulphur have strong avidity.Ti content generally is controlled at below 0.08% in the ultra low-carbon steel; Steel of the present invention calculates according to the composition design formula, and for realizing that part VC dissolving is to obtain the target of bake hardening performance in the cold-reduced sheet recrystallization annealing process, Ti content should not exceed 0.04%.
Vanadium (V): the solubleness of V in steel is more much bigger than Ti; Because it is vanadium down has lower degree of supersaturation in the austenitic temperature scope, thereby very weak when thermomechanical treatment to the influence of recrystallization process.And in the hot continuous rolling process, vanadium to improve rolling load require little.In the vanadium micro-alloyed steel, it is cold that the relatively large solubleness of its compound can make the precipitation process in the soft steel be, and directly be cooled to the ferrite scope; Like this, just there is considerable precipitation hardening to take place.
The avidity of vanadium and carbon significantly reduces than the avidity of titanium and carbon.TiC then could dissolve in austenitic high-temperature zone; And the carbon of vanadium, nitrogen compound dissolve at austenitic cold zone, and VC even promptly begun dissolving being higher than 750 ℃ finishes 800～900 ℃ of scopes dissolvings.For avoiding the meaningless interpolation of vanadium, steel of the present invention calculates according to the composition design formula, and the addition scope that draws V is 0.030～0.070%, and preferred 0.04%.
With reference to above-mentioned experimental study result, the target value of main coherent element content is preferably in the steel of the present invention:
C≤0.003%, Si≤0.015%, Mn 0.15～0.32%, P 0.03～0.06%, S≤0.006%, Ti 0.01～0.035%, and Als 0.01～0.05%, V 0.030～0.060%, N≤0.003%, all the other are Fe, wherein Mn%/P%=5～6, Ti% 〉=(48/14) N%+ (48/32) S%, V% 〉=(51/12) C%.
2. production technique is to the ultra-low carbon baking hardening steel performance indexes
● the influence of coiling temperature
The variation of r value, BH value may be different relevant with carbide, nitride precipitate pattern.Along with the raising of coiling temperature, carbide is separated out increase, and helps particle aggregation and grow up, and in the short annealing process, matrix is not finished recrystallize before the dissolving as yet again at thick precipitate, obtains flourishing favorable texture, thereby improves the r value; Because high coiling temperature makes carbide particle thick, higher solid solution carbon amount is arranged in short annealing, thereby obtain higher BH value.
● the influence of annealing temperature and annealing time
The metallographic structure of different annealing temperature during 700 ℃ of annealing, has free cementite to exist, and intracrystalline carbide quantity is few, is a thinner ferritic structure that waits; Perlite occurred during 780 ℃ of annealing, distribution of carbides is on crystal boundary, and ferrite crystal grain is grown up; During 850 ℃ of annealing temperatures, microstructure is similar to 780 ℃ of annealing, but visible ferrite crystal grain further grows up, and grain-size increases with the raising of annealing temperature, causes yield strength to reduce.In addition, the r value increases along with the raising of annealing temperature.
During the difference annealing time, the 580s annealed structure is for waiting axle ferritic structure, and carbide is distributed in crystal boundary more, and intracrystalline is less; Along with the increase of annealing time, ferrite grain size increases, and has occurred pearlitic structure during 690s, and perlite quantity further increases during 870s.Along with increasing of perlite quantity, grain boundary carbide quantity reduces.Yield strength reduces.Along with the increase of annealing time, average plastic strain ratio r
mValue increases.
The BH value is on a declining curve with the increase of the raising of annealing temperature and annealing time.In the grain growth stage behind recrystallize, raising and annealing time prolongation along with temperature cause high r value.
The process characteristic of continuous annealing is a rapid heating, isothermal treatment for short time and cooling fast, and soluble solids separates out time in the long overaging stage that mainly occurs in the steel.But the carbon concentration of matrix is determined by annealing temperature and annealing time when entering overaging, when adopting higher annealing temperature and long annealing time, owing in the matrix higher carbon concentration is arranged, separating out than being easier to of overaging stage carbon obtains lower dissolved carbon content the BH value reduced.
3. overaging temperature and predeformation amount are to the influence of BH value
● the overaging Temperature Influence
The BH value raises along with the rising of overaging temperature, and yield strength then reduces, and unit elongation improves.The BH value raises to improve with the overaging temperature and may be interpreted as higher overaging temperature and make atomic diffusion help separating out of carbon easily, causes the reduction of solid solution carbon; Under higher overaging temperature, the solubleness of carbon is higher relatively in the matrix on the other hand, and is kept after the secondary cooling.The two common result has just determined the size of annealing production board BH value.
● the influence of predeformation amount
The generation of baking hardenability comes down to the result of high-temp strain timeliness, and the solid solution carbon atom produces BH to the pinning effect of dislocation.The diffusion process at solid solution carbon atom dispiration place is subjected to the influence of storing temperature, dislocation desity and storing time, has caused the variation of dislocation place accumulative amount of carbon atom, thereby has made the dislocation number of variations that is subjected to the carbon atom pinning effect, and the BH value is exerted an influence.Diffusion motion is done at carbon atom dispiration place, its motivating force derives from it and interaction of dislocation energy, this interaction energy of four directions distortion initiation that carbon atom produces in the octahedral interstice of matrix lattice is calculated to the dislocation place along with carbon atom expands, and interaction can reduce.During the hot activation sufficient condition, help carbon atom to realize its proliferation activity, this also is storing temperature has remarkably influenced to the BH value a reason.By diffusion coefficient D=D
0e
-Δ LiRIFormula as can be known, along with the rising of temperature, spread coefficient increases.By contrast, predeformation amount only causes that dislocation desity changes and influence the interaction energy, but because the rangeability of predeformation amount is little, so the dislocation desity variation is also little.Therefore, predeformation amount is less to the influence of BH value.
Predeformation amount is that variation by dislocation desity causes the difference of diffusion drive power to realize to the influence of BH value.The increase of dislocation desity can make the velocity of diffusion of carbon atom increase, so improve its BH value.But because the solid solution carbon content is certain, thereby be subjected to the dislocation number of its pinning also just to have a ultimate value.Along with dislocation desity increases to after dislocation outnumbers this ultimate value in the crystal grain, just have some free movable dislocations and exist, and its number can increase along with the continuous increase of dislocation desity, thereby the BH value is decreased.
For composition and processing parameter fixed ultra-low carbon baking hardening steel plate, the BH value has certain saturability, promptly has a maximum value, and this is because the certain cause of solid solution carbon atom amount.
With reference to above-mentioned result of study, preparation method of the present invention and technological process control are as follows:
(1) process for making control:
Steel of the present invention adopts blast-melted pre-treatment, furnace outer refining technology, makes [S]≤0.005% into the stove molten iron, the content of control inclusion morphology and harmful residual element; Utilize the converter top bottom blowing, carry out vacuum decarburization and degassing processing and trimming, C, N, S be controlled at 0.005%, 0.004% respectively, below 0.015%, the ladle beam adopts long nozzle argon envelope gas shield casting, and adds the aluminium final deoxygenation with the aluminum steel machine; Middle bag adopts the T-1 covering slag, and crystallizer adopts low carbon protective slag, thereby guarantees the high cleanliness of steel; And adopt induction stirring and continuous casting gently to depress, improve the homogeneity of the composition and the tissue of steel as far as possible.
(2) rolling technology control:
Steel billet of the present invention is produced on 1700 hot continuous mills: adopt two stage cooling controlling and rolling controlling process in eight sections walking beam furnace heating of hot rolling mill.Rough rolling step, carry out the multi-pass aximal deformation value in the high temperature austenite district rolling, makes austenite crystal fully broken; The finish rolling stage is finished seven passage continuous rollings in the austenitic area, adopt the laminar flow type of cooling that the band steel is carried out controlled chilling, with obtain evenly, the ferrite crystal grain tissue of refinement and good comprehensive mechanical property.Billet heating temperature: 1170～1230 ℃; Finishing temperature: 880～920 ℃; 15～30 ℃/s of controlled chilling speed; Coiling temperature: 670～730 ℃.
For avoiding falling into the rolling mixed crystal defect that causes of α+γ two-phase region, steel control hot rolling finishing temperature of the present invention is a little more than A
R3Transformation temperature.
Steel hot rolled coil of the present invention carries out five passage tandem rollings through overpickling on 1700 cold continuous rollings, the finished product thickness of slab is 0.5～2.0mm; Under 820～850 ℃, carry out continuous annealing then, carry out smooth, finishing, check feature at last.
Bake hardening deep-draw autobody sheet is used for the automobile panel outside plate more, requires the planeness height of supply of material steel plate, and strip shape quality is good.The plate shape on-line Control of cold rolled strip is that the tension stress lateral distribution measured with measuring roll is as distinguishing rule, but usually be accompanied by multiple additional stress in the actual production, as measuring roller surface axial temperature skewness, band transverse temperature skewness, measuring roller deflection deformation, reeling machine axis deviation, roll coil of strip gabarit convexity change, strip edge covers incomplete etc. to the outermost measurement zone; Wherein remarkable with the additional stress influence of band transverse temperature skewness generation especially, so steel emphasis of the present invention carries out temperature compensation calculating.Consider the axial symmetry of roller temperature compensation, the temperature compensation function adopts four even function forms, has both reduced the technological transformation cost, succinct again easily control.
With the steel of the present invention that contains 0.02%Ti+0.04%V is example, detect metallographic structure, inclusion, the grain fineness number of steel plate sample, result such as Fig. 1 are according to GB/T13298-91, GB/T10561-05, GB/T6394-02 standard, surveying steel plate metallographic structure of the present invention is ferrite, grain size number is 7～8.5 grades, inclusion is point-like, and grading is below the D1 level.
Comparative study steel of the present invention and Ti+Nb-BH steel annealed sheet grain fineness number, 340MPa grade ultra-low-carbon Ti+Nb-BH cold-rolled steel sheet shown in Figure 2 metallographic structure after 850 ℃, 880 ℃, 910 ℃ recrystallization annealing respectively, its main chemical compositions is as follows:
Table 1 340MPa grade ultra-low-carbon Ti+Nb-BH steel chemical composition weight %
| Steel grade | C | Si | Mn | P | S | Ti | Nb | N |
| Ti+Nb-BH | 0.002 | 0.02 | 0.23 | 0.084 | 0.006 | 0.020 | 0.035 | 0.0035 |
(a) 910 ℃ of annealing of 880 ℃ of annealing of 850 ℃ of annealing (b) (c)
Comparison diagram 1, Fig. 2 find, of the present invention to contain vanadium BH steel very big with the BH structure of steel grain fineness number difference that contains niobium and/or titanium.When the former contained 0.02%Ti+0.04%V, it is big that grain size and common IF steel are compared Bianization Bu Suan, and grain size number is suitable substantially, and the Wuhan Iron and Steel Plant production practice show that its production board unit elongation can reach more than 43%; And the latter is when containing 0.02%Nb, and the annealed structure grain fineness number promptly sharply descends, and grain refining is very obvious, thereby unit elongation value, work hardening exponent n value are lower, and for example domestic certain steel mill adopts and adds the A that Nb, Ti method produced, supplied the BH340 steel plate of Cherry's automobile works
80mm=34%～38%, B180H
1, B180H
2The A of steel plate
80mm=35%～41%.
Doctor L.Meyer of Thyssen Iron And Steel Company has studied the influence of micro alloying elements such as Nb, V, Ti to steel plate ferrite crystal grain tissue, as shown in Figure 3.
By the result of study among Fig. 3, we also can clearly reach a conclusion, and concerning Ultra-low carbon BH steel plate, adopt the V microalloying than adopting Nb, Ti microalloying, and are much smaller to the impact effect of production board ferrite crystal grain refinement.
Steel of the present invention draws in the skin pass rolling test of cold rolling mill, and when main mill adopted permanent rolling load rolling, the tapering of coiling tension changed and can influence be with the thick poor precision of steel, thereby influences belt plate shape; And when main mill adopted permanent unit elongation rolling, coiling tension did not have influence substantially to the belt plate shape quality.The optimization flattening process of steel of the present invention is: under the prerequisite that guarantees the belt plate shape quality, and fixing lower tension force, adjusting rolling pressure is about 450 tons, unit elongation then maintains 1.2%～1.4%.
The present invention is because VC phase solid solution equilibrium temperature is low far beyond NbC, so cold rolling mill has now under the annealing device condition at home, produces the BH auto sheet that has the excellent deep drawability dent resistance energy stable with height concurrently.The present invention is a kind of novel cover panel steel plate with high strength, good deep drawability, high dent resistance energy, can satisfy the domestic automobile manufacturer production fully and be badly in need of, and has realized loss of weight, energy-saving and cost-reducing, eco-friendly target.
Description of drawings
Fig. 1 is steel plate metallurgical structure figure of the present invention
Fig. 2 is 340MPa grade ultra-low-carbon Ti+Nb-BH steel annealed sheet metallurgical structure figure
Fig. 3 is the influence synoptic diagram of microalloy element to quenched and tempered steel and non-hardened and tempered steel ferrite grain size
Embodiment
The invention will be further described below in conjunction with specific embodiment.
Embodiment 1: smelt vanadium treated bake hardening deep-draw autobody sheet of the present invention, the chemical ingredients of steel (% by weight) is: C 0.0019, and Si 0.014, and Mn 0.24, P 0.041, and S 0.003, and Als 0.031, and Ti 0.017, V 0.039, and N 0.0022, and all the other are Fe.Preparation method of the present invention comprises steel-making, hot rolling, cold rolling, continuous annealing and formation process, at first adopts blast-melted pre-treatment, furnace outer refining technology, makes [S]≤0.005% into the stove molten iron, the content of control inclusion morphology and harmful residual element; Utilize the converter top bottom blowing, carry out vacuum decarburization and degassing processing and trimming, C, N, S are controlled at 0.0019%, 0.0022%, 0.003% respectively, and the ladle beam adopts long nozzle argon envelope gas shield casting, and add the aluminium final deoxygenation with the aluminum steel machine; Middle bag adopts the T-1 covering slag, and crystallizer adopts low carbon protective slag.The Heating temperature of steel billet is 1200 ℃ during hot rolling, and heating is with the plate temperature difference≤25 ℃, and the roughing temperature out is 1080 ℃, and the finish rolling temperature in is 1040 ℃, and finishing temperature is 900 ℃; Adopt the laminar flow cooling that the band steel is carried out controlled chilling after finishing hot fine rolling, 20 ℃/s of controlled chilling speed batches under 700 ℃ of temperature, and hot rolled coil carries out five passage tandem rollings through pickling on four roller cold continuous rollings, and the finished product thickness of slab is 0.80mm; The recrystallization annealing that under 830 ℃, is incubated 90 seconds then, the annealing back is smooth, unit elongation 1.2%, check finished product steel belt performance is R
EL=220MPa, R
m=355MPa, A
80mm=43%, r
90=3.05, n
90=0.26, BH=38MPa; 180 ° of clod washes, d=0 is intact.At Abdeckteils such as certain sedan-making plant punching out car upper top cover, engine covers, properties percent of pass reaches 100%; The entrucking part dimension is stable, and no warping phenomenon takes place, and has good dent resistance, and running condition is good.
Embodiment 2: smelt vanadium treated bake hardening deep-draw autobody sheet of the present invention, the chemical ingredients of steel (% by weight) is: C 0.005, and Si 0.03, and Mn 0.4, and P 0.079, and S 0.014, and Als 0.07, and Ti 0.04, and V 0.04, and N 0.004, and all the other are Fe.Preparation method of the present invention comprises steel-making, hot rolling, cold rolling, continuous annealing and formation process, at first adopts blast-melted pre-treatment, furnace outer refining technology, the content of control inclusion morphology and harmful residual element; Utilize the converter top bottom blowing, carry out vacuum decarburization and degassing processing and trimming, C, N, S are controlled at 0.005%, 0.004%, 0.014% respectively, and the ladle beam adopts long nozzle argon envelope gas shield casting, and add the aluminium final deoxygenation with the aluminum steel machine; Middle bag adopts the T-1 covering slag, and crystallizer adopts low carbon protective slag.The Heating temperature of steel billet is 1180 ℃ during hot rolling, and heating is with the plate temperature difference≤25 ℃, and the roughing temperature out is 1100 ℃, and the finish rolling temperature in is 1040 ℃, and finishing temperature is 900 ℃; Adopt the laminar flow cooling that the band steel is carried out controlled chilling after finishing hot fine rolling, 15 ℃/s of controlled chilling speed batches under 695～715 ℃ of temperature, and hot rolled coil carries out five passage tandem rollings through pickling on four roller cold continuous rollings, and the finished product thickness of slab is 0.5mm; The recrystallization annealing that under 840 ℃, is incubated 90 seconds then, the annealing back is smooth, unit elongation 1.4%, check finished product steel belt performance is R
EL=245MPa, R
m=380MPa, A
80mm=39%, r
90=2.01, n
90=0.20, BH=49MPa; 180 ° of clod washes, d=0 is intact.
Embodiment 3: smelt vanadium treated bake hardening deep-draw autobody sheet of the present invention, the chemical ingredients of steel (% by weight) is: C 0.0015, and Si 0.015, and Mn 0.1, and P 0.02, and S 0.003, and Als 0.01, and Ti 0.01, and V 0.02, and N 0.0019, and all the other are Fe.The preparation method is with embodiment 1, and check finished product steel belt performance is R
EL=212MPa, R
m=345MPa, A
80mm=48%, r
90=3.20, n
90=0.30, BH=33MPa; 180 ° of clod washes, d=0 is intact.
Embodiment 4: smelt vanadium treated bake hardening deep-draw autobody sheet of the present invention, the chemical ingredients of steel (% by weight) is: C 0.0030, S i 0.014, and Mn 0.30, P 0.052, and S 0.003, and Als 0.030, and Ti 0.025, V 0.04, and N 0.0030, and all the other are Fe.The preparation method is with embodiment 2, and check finished product steel belt performance is R
EL=225MPa, R
m=359MPa, A
80mm=41%, r
90=2.49, n
90=0.24, BH=41MPa; 180 clod washes, d=0 is intact.
Comparative Examples: smelt compared steel of the present invention, the chemical ingredients of steel (% by weight) is: C0.007, and Si 0.012, and Mn 0.17, P 0.063, and S 0.019, and Als 0.038, and Ti 0.020, Nb 0.020, and N 0.0051 adds solution strengthening element P, Mn 2. in the ratio of Mn%/P%=5～6; 3. control Ti% in the steel plate 〉=(48/14) N%+ (48/32) S%, press lower limit control Ti content; 4. control V% 〉=(51/12) C%, all the other are Fe and unavoidable impurities.Adopt water-cooled that the band steel is carried out controlled chilling after finishing hot rolling, batch under 680～705 ℃ of temperature, hot rolled coil is rolled on 4-roller cold rolling mill through pickling, and the finished product thickness of slab is 0.80mm; The recrystallization annealing that under 830 ℃, is incubated 90 seconds then, the annealing back is smooth, unit elongation 1.2%, check finished product steel belt performance is R
EL=230MPa, R
m=355MPa, A
80mm=31%, r
90=1.33, n
90=0.15, BH=29MPa; 180 ° of clod washes, d=0, defective; Its mechanical property can not satisfy the production requirement of automobile deep-draw parts.
Claims (6)
1, a kind of vanadium treated bake hardening type deep drew steel plates of saloon sedan, its Chemical Composition is by weight percentage:
C≤0.003%, Si≤0.015%, Mn 0.15～0.32%, P 0.03～0.06%, S≤0.006%, Ti 0.01～0.035%, and Als 0.01～0.05%, V 0.030～0.060%, N≤0.003%, all the other are Fe, wherein Mn%/P%=5～6, Ti% 〉=(48/14) N%+ (48/32) S%, V% 〉=(51/12) C%.
2, according to a kind of vanadium treated bake hardening type deep drew steel plates of saloon sedan of claim 1, wherein the content of vanadium is 0.04% in the Chemical Composition.
3, according to a kind of vanadium treated bake hardening type deep drew steel plates of saloon sedan of claim 1 or 2, the thickness of wherein said steel plate is 0.50～2.0mm.
4, according to a kind of vanadium treated bake hardening type deep drew steel plates of saloon sedan of claim 1 or 2, wherein said steel plate is perpendicular to rolling direction: yield strength 〉=210MPa, tensile strength 〉=340MPa, plastic strain ratio r
90〉=1.8, work hardening exponent n
90〉=0.20, unit elongation A
80mm〉=38%, BH value 〉=30MPa.
5, a kind of vanadium treated bake hardening type deep drew steel plates of saloon sedan preparation method according to claim 1, its Chemical Composition is by weight percentage: C≤0.003%, Si≤0.015%, Mn 0.15～0.32%, P 0.03～0.06%, S≤0.006%, Ti 0.01～0.035%, Als 0.01～0.05%, and V 0.030～0.060%, N≤0.003%, all the other are Fe, Mn%/P%=5～6 wherein, Ti% 〉=(48/14) N%+ (48/32) S%, V% 〉=(51/12) C%, it comprises steel-making, hot rolling, cold rolling, continuous annealing and formation process, wherein hot rolling technology is controlled to be: the Heating temperature of steel billet is 1200 ± 30 ℃, and heating is with the plate temperature difference≤25 ℃, 1080 ± 20 ℃ of roughing temperature outs, the finish rolling temperature in is 1040 ± 20 ℃, finishing temperature is 900 ± 20 ℃, and 15～30 ℃/s of controlled chilling speed, coiling temperature are 700 ± 20 ℃; Cold-rolling process is controlled to be: total draft is 75%～80%, and annealing temperature is 820～850 ℃, smooth temperature≤45 ℃, and smooth unit elongation is 0.9%～1.5%.
6, a kind of vanadium treated bake hardening type deep drew steel plates of saloon sedan preparation method according to claim 5 wherein need control Chemical Composition in the preparation process: 1. add Ti, V simultaneously, fixedly the C in the strand, N interstitial atom as follows; 2. in the ratio of Mn%/P%=5～6, add solution strengthening element P, Mn; 3. control Ti% in the steel plate 〉=(48/14) N%+ (48/32) S%, press lower limit control Ti content; 4. control V% 〉=(51/12) C%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006101250029A CN100436632C (en) | 2006-11-10 | 2006-11-10 | Vanadium treated bake hardening type deep drew steel plates of saloon sedan, and preparation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006101250029A CN100436632C (en) | 2006-11-10 | 2006-11-10 | Vanadium treated bake hardening type deep drew steel plates of saloon sedan, and preparation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1958826A CN1958826A (en) | 2007-05-09 |
| CN100436632C true CN100436632C (en) | 2008-11-26 |
Family
ID=38070681
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2006101250029A Expired - Fee Related CN100436632C (en) | 2006-11-10 | 2006-11-10 | Vanadium treated bake hardening type deep drew steel plates of saloon sedan, and preparation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100436632C (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101912874B (en) * | 2010-07-14 | 2012-07-04 | 宁波钢铁有限公司 | Production method of preventing from coiling and pulling narrow of hot-rolled low carbon strip steels used for cold-rolled base plates |
| CN106399836B (en) * | 2016-06-21 | 2018-10-02 | 宝山钢铁股份有限公司 | A kind of baking hardening type high-strength steel and its manufacturing method |
| CN106498139B (en) * | 2016-11-22 | 2018-11-09 | 首钢京唐钢铁联合有限责任公司 | Process method and device for producing IF steel |
| CN108796382B (en) * | 2017-04-27 | 2020-10-27 | 宝山钢铁股份有限公司 | Boron-containing steel suitable for large-deformation and easy-to-punch aluminum-coated substrate and production method thereof |
| CN108796363B (en) * | 2017-04-27 | 2020-10-27 | 宝山钢铁股份有限公司 | High-surface-quality aluminum-coated substrate steel suitable for large deformation and stamping and production method thereof |
| CN107812786A (en) * | 2017-09-15 | 2018-03-20 | 宁波钢铁有限公司 | A kind of hot rolling technology for being used to produce the electrical sheet without metal flow accumulation defect |
| CN112048662A (en) * | 2020-08-03 | 2020-12-08 | 河钢股份有限公司 | Age-resistant bake-hardening steel plate, galvanized plate thereof and production method |
| CN112090958B (en) * | 2020-08-03 | 2022-09-16 | 大冶特殊钢有限公司 | Rolling process for controlling actual grain size of low-carbon deep-drawing steel |
| CN112063927A (en) * | 2020-09-17 | 2020-12-11 | 南京奇纳金属材料科技有限公司 | High-formability ultra-low carbon bake-hardening steel plate and preparation method thereof |
| CN115558755B (en) * | 2022-09-21 | 2025-04-08 | 武汉钢铁有限公司 | Method for producing bake hardening steel with plate width more than or equal to 1800mm |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0625755A (en) * | 1992-07-09 | 1994-02-01 | Nippon Steel Corp | Method for producing alloyed hot-dip galvanized cold-rolled steel sheet for deep drawing having excellent bake hardenability and powdering resistance |
| JPH0860298A (en) * | 1994-08-17 | 1996-03-05 | Nippon Steel Corp | Steel plate for DI can with excellent neck workability and pressure resistance |
| CN1209174A (en) * | 1996-02-27 | 1999-02-24 | 伯利恒钢铁公司 | Bake hardenable vanadium contg. steel |
| CN1277639A (en) * | 1998-06-30 | 2000-12-20 | 新日本制铁株式会社 | Cold rolled steel sheet excellent in baking hardenability |
| CN1793405A (en) * | 2005-12-30 | 2006-06-28 | 武汉钢铁(集团)公司 | Colding rolling weather resistant depth impacting plate for vehicle and mfg. method thereof |
-
2006
- 2006-11-10 CN CNB2006101250029A patent/CN100436632C/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0625755A (en) * | 1992-07-09 | 1994-02-01 | Nippon Steel Corp | Method for producing alloyed hot-dip galvanized cold-rolled steel sheet for deep drawing having excellent bake hardenability and powdering resistance |
| JPH0860298A (en) * | 1994-08-17 | 1996-03-05 | Nippon Steel Corp | Steel plate for DI can with excellent neck workability and pressure resistance |
| CN1209174A (en) * | 1996-02-27 | 1999-02-24 | 伯利恒钢铁公司 | Bake hardenable vanadium contg. steel |
| CN1277639A (en) * | 1998-06-30 | 2000-12-20 | 新日本制铁株式会社 | Cold rolled steel sheet excellent in baking hardenability |
| CN1793405A (en) * | 2005-12-30 | 2006-06-28 | 武汉钢铁(集团)公司 | Colding rolling weather resistant depth impacting plate for vehicle and mfg. method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1958826A (en) | 2007-05-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100436632C (en) | Vanadium treated bake hardening type deep drew steel plates of saloon sedan, and preparation method | |
| CN110453146B (en) | A kind of Cr alloyed steel without yield plateau and preparation method thereof | |
| CN100577845C (en) | High plastic-strain ratio galvanized steel sheet and production method | |
| CN107619993B (en) | Cold-rolled martensite steel plate with yield strength of 750MPa and manufacturing method thereof | |
| CN102586688B (en) | A kind of dual phase sheet steel and manufacture method thereof | |
| US12134809B2 (en) | High strength steel sheet having excellent high-temperature elongation characteristic, warm-pressed member, and manufacturing methods for the same | |
| CN103080357B (en) | High-strength cold-rolled steel sheet having excellent stretch flange properties, and process for production thereof | |
| CN108368590B (en) | Ultrahigh-strength steel sheet having excellent chemical conversion treatability and bending workability, and method for producing same | |
| CN112095046B (en) | A kind of ultra-high-strength cold-rolled DH1180 steel and preparation method thereof | |
| CN106256918B (en) | A kind of the Automobile flywheel cold-strip steel and its manufacturing method of precision stamping processing | |
| CN110073024B (en) | Ultrahigh-strength steel sheet having excellent bending workability and method for producing same | |
| CN105274432A (en) | 600 MPa-grade high-yield-ratio high-plasticity cold-rolled steel plate and manufacturing method thereof | |
| CN107043890B (en) | A kind of 1.5~3.0mm of thickness yield strength is greater than the Hot Rolling Automobile steel and its manufacturing method of 700MPa | |
| CN106636907A (en) | Thin gauge carriage body steel belt with yield strength of 600MPa, and manufacturing method of thin gauge carriage body steel belt | |
| CN109930068A (en) | A kind of 800MPa grades of ultra-thin specification cold-rolled biphase steel and preparation method thereof | |
| US20220010394A1 (en) | High-yield-ratio cold-rolled dual-phase steel and manufacturing method therfor | |
| CN106498296A (en) | Manufacturing method of high-strength steel with yield strength of 1100MPa | |
| CN109943765B (en) | 800 MPa-grade cold-rolled dual-phase steel with high yield ratio and preparation method thereof | |
| CN111394658B (en) | 980 MPa-grade cold-rolled Q & P steel suitable for conventional continuous annealing production line and manufacturing method thereof | |
| CN110747405B (en) | One-thousand-megapascal-grade cold-rolled bainite steel plate suitable for rolling and preparation method thereof | |
| CN105861929A (en) | 440 MPa-level cold rolling high-strength IF steel and production method thereof | |
| CN114045441A (en) | Reinforced plastic dual-phase steel for 800 MPa-level continuous annealing and preparation method thereof | |
| CN102534373B (en) | Super-high strength cold rolled steel belt suitable for rolling formation and manufacture method of super-high strength cold rolled steel belt | |
| CN105779874B (en) | Cr Nb system 780MPa levels hot-rolled dual-phase steels and its production method | |
| CN110331344A (en) | A kind of Rm >=600MPa beam steel that strength character is stable and production method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20170711 Address after: 430083, Hubei Wuhan Qingshan District Factory No. 2 Gate joint stock company organs Patentee after: Wuhan iron and Steel Company Limited Address before: 430083 patent room, Wuhan Science and technology innovation department, No. 2, gate, Gate No. 3, Qingshan District, Wuhan, Hubei Patentee before: Wuhan Iron & Steel (Group) Corp. |
|
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20081126 Termination date: 20181110 |