CN104120347B - A kind of cold-rolled steel sheet and preparation method thereof - Google Patents
A kind of cold-rolled steel sheet and preparation method thereof Download PDFInfo
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Abstract
The present invention discloses a kind of cold-rolled steel sheet and preparation method thereof, the method comprises: by slab successively through hot rolling, batch, cold rolling, annealing, polishing and straightening, wherein, after described hot rolling and before described batching, after first the intermediate slab obtained after hot rolling being cooled to 780-820 DEG C with the speed of cooling of 70-90 DEG C/s, then be cooled to the temperature of batching with the speed of cooling of 15-25 DEG C/s; Described temperature of batching is 730-770 DEG C; Described cold rolling draft is 75-85%; The mode of described annealing is continuous annealing, and in the process of described annealing, the intermediate slab obtained after cold rolling is successively through heating zone, soaking zone, cooling section, low temperature maintaining segment, overaging section and a cooling twice section.According to method of the present invention, can for a kind of yield strength within the scope of 140-180MPa, and forming property excellent high-ductility strain ratio cold-rolled steel sheet.
Description
Technical field
The present invention relates to a kind of cold-rolled steel sheet and preparation method thereof.
Background technology
Along with the development of automobile industry, the requirement of market to automotive sheet improves constantly, in order to meet the forming requirements of market deep-drawing, particularly in order to meet the requirement of automobile, the overall impact briquetting component of motorcycle field (being such as automobile front wall right side plate), need a kind ofly to there is certain yield strength and there is the steel plate of excellent impact briquetting performance.
At present, as the method for the special ultra-deep punching cold-rolling steel sheet of preparation, CN101514392A discloses the continuous annealing process of a kind of deep-draw and extra-deep drawing sheet steel.This technique comprises: steel plate through cleaning, enters continuous annealing furnace, speed 150 ~ 350m/min before annealing, adopts nitrogen hydrogen mixeding gas ejection surface of steel plate, to protect, anti-oxidation, make steel billet temperature be heated to 120 ~ 180 DEG C simultaneously to steel plate; Again to steel plate heating, make its temperature reach 750 ~ 780 DEG C, and be incubated 40 ~ 70s; Then 400 ~ 460 DEG C are cooled to steel plate, and are incubated 60 ~ 300s and carry out Wetted constructures, be cooled to normal temperature subsequently.Owing to adopting overaging annealing process, the carbide in steel is fully separated out, ensure that household electrical appliances steel plate and auto sheet punching performance and ultra-deep punching performance.But the impact briquetting performance of the steel plate obtained by this technique also needs further raising.
Summary of the invention
The object of the present invention is to provide a kind of yield strength within the scope of 140-180MPa, and cold-rolled steel sheet and preparation method thereof of the excellent high-ductility strain ratio of forming property.
The present inventor is found by deep research: by controlling the operations such as slab moiety, hot rolling, cold rolling, annealing, particularly in the control of the control of speed of cooling, cold rolling middle draft, continuous annealing process, the temperature of each processing section is controlled in hot rolling, refinement also stablizes ferrite crystalline size, thus yield strength can be obtained within the scope of 140-180MPa, and the cold-rolled steel sheet of the excellent high-ductility strain ratio of forming property, thus complete the present invention.
That is, the invention provides a kind of preparation method of cold-rolled steel sheet, the method comprises: by slab successively through hot rolling, batch, cold rolling, annealing, polishing and straightening, wherein,
After described hot rolling and before described batching, after first the intermediate slab obtained after hot rolling being cooled to 780-820 DEG C with the speed of cooling of 70-90 DEG C/s, then be cooled to the temperature of batching with the speed of cooling of 15-25 DEG C/s;
Described temperature of batching is 730-770 DEG C;
Described cold rolling draft is 75-85%;
The mode of described annealing is continuous annealing, in the process of described annealing, the intermediate slab obtained after cold rolling is successively through heating zone, soaking zone, a cooling section, low temperature maintaining segment, overaging section and cooling twice section, described cold rolling after the intermediate slab that obtains in described heating zone, described soaking zone, a described cooling section, described low temperature maintaining segment, terminal temperature in described overaging section and described cooling twice section is respectively 770-820 DEG C, 850-880 DEG C, 210-300 DEG C, 250-340 DEG C, 200-290 DEG C, less than 100 DEG C, the residence time is respectively 30-80s, 30-60s, 260-480s, 60-100s, 240-300s, 120-180s,
Consisting of of described slab: C:0.001-0.005 % by weight, Si :≤0.03 % by weight, Mn:0.1-0.3 % by weight, P:0.005-0.015 % by weight, S:0.005-0.015 % by weight, Ti:0.4-0.9 % by weight, Nb:0.005-0.03 % by weight, Al:0.01-0.08 % by weight, surplus is Fe and inevitable impurity.
The present invention also provides the cold-rolled steel sheet prepared by aforesaid method.
Adopt cold-rolled steel sheet prepared by preparation method of the present invention, its finished product mechanical property reaches yield strength R
eLfor 140-180MPa, tensile strength R
mfor 280-320MPa, elongation after fracture A
80>=44%, plastic strain ratio r
90>=3.5, work hardening exponent n
90>=0.25, be the steel plate that one is specially adapted to automobile, the overall impact briquetting component of motorcycle field (being such as automobile front wall right side plate), there are excellent market outlook.
Other features and advantages of the present invention are described in detail in embodiment part subsequently.
Accompanying drawing explanation
Accompanying drawing is used to provide a further understanding of the present invention, and forms a part for specification sheets, is used from explanation the present invention, but is not construed as limiting the invention with embodiment one below.In the accompanying drawings:
Fig. 1 is the microstructure picture of cold-rolled steel sheet prepared by the embodiment of the present invention 1.
Fig. 2 is the microstructure picture of cold-rolled steel sheet prepared by the embodiment of the present invention 2.
Fig. 3 is the microstructure picture of cold-rolled steel sheet prepared by the embodiment of the present invention 3.
Fig. 4 is the microstructure picture of the cold-rolled steel sheet of comparative example 1 of the present invention preparation.
Fig. 5 is the microstructure picture of the cold-rolled steel sheet of comparative example 2 of the present invention preparation.
Fig. 6 is the microstructure picture of the cold-rolled steel sheet of comparative example 3 of the present invention preparation.
Fig. 7 is the microstructure picture of the cold-rolled steel sheet of comparative example 4 of the present invention preparation.
Embodiment
Below the specific embodiment of the present invention is described in detail.Should be understood that, embodiment described herein, only for instruction and explanation of the present invention, is not limited to the present invention.
The invention provides a kind of preparation method of cold-rolled steel sheet, the method comprises: by slab successively through hot rolling, batch, cold rolling, annealing, polishing and straightening, wherein, after described hot rolling and before described batching, after first the intermediate slab obtained after hot rolling being cooled to 780-820 DEG C with the speed of cooling of 70-90 DEG C/s, then be cooled to the temperature of batching with the speed of cooling of 15-25 DEG C/s, described temperature of batching is 730-770 DEG C, described cold rolling draft is 75-85%, the mode of described annealing is continuous annealing, in the process of described annealing, the intermediate slab obtained after cold rolling is successively through heating zone, soaking zone, a cooling section, low temperature maintaining segment, overaging section and cooling twice section, described cold rolling after the intermediate slab that obtains in described heating zone, described soaking zone, a described cooling section, described low temperature maintaining segment, terminal temperature in described overaging section and described cooling twice section is respectively 770-820 DEG C, 850-880 DEG C, 210-300 DEG C, 250-340 DEG C, 200-290 DEG C, less than 100 DEG C, the residence time is respectively 30-80s, 30-60s, 260-480s, 60-100s, 240-300s, 120-180ss, consisting of of described slab: C:0.001-0.005 % by weight, Si :≤0.03 % by weight, Mn:0.1-0.3 % by weight, P:0.005-0.015 % by weight, S:0.005-0.015 % by weight, Ti:0.4-0.9 % by weight, Nb:0.005-0.03 % by weight, Al:0.01-0.08 % by weight, surplus is Fe and inevitable impurity.
In the present invention, although just can obtain the cold-rolled steel sheet of better intensity and more excellent forming property when the composition of slab is in above-mentioned scope, but in order to obtain the performance of the cold-rolled steel sheet that enhancing obtains, under preferable case, consisting of of described slab: C:0.002-0.004 % by weight, Si:0.01-0.02 % by weight, Mn:0.1-0.25 % by weight, P:0.005-0.012 % by weight, S:0.005-0.012 % by weight, Ti:0.6-0.9 % by weight, Nb:0.01-0.025 % by weight, Al:0.03-0.07 % by weight, surplus is Fe and inevitable impurity.More preferably, consisting of of described slab: C:0.002-0.004 % by weight, Si:0.01-0.02 % by weight, Mn:0.15-0.25 % by weight, P:0.005-0.012 % by weight, S:0.005-0.012 % by weight, Ti:0.65-0.85 % by weight, Nb:0.01-0.025 % by weight, Al:0.035-0.07 % by weight, surplus is Fe and inevitable impurity.When the moiety of described slab is in above-mentioned scope, can through hot rolling of the present invention, batch, cold rolling, annealing, after polishing and straightening technique, intensity and the better cold-rolled steel sheet of forming property will be obtained.
In the present invention, consider the over-all properties of purity of steel and product, the carbon content in described slab needs to control in above-mentioned scope, if carbon (C) content is more than 0.005 % by weight, then the plasticity of steel plate reduces, and forming property worsens; Moreover the content of silicon (Si) needs to control in lower scope; Manganese (Mn) can increase the intensity of described slab, and can be combined into MnS with sulphur (S), prevents the thermal crack because FeS causes simultaneously, but Mn too high levels, the welding property of steel can be affected, therefore, need the content of Mn to control in above-mentioned scope.In addition, phosphorus (P), as strengthening element, needs to be added in above-mentioned scope.Consider the economy of steel making working procedure and the effect of Calcium treatment, S is controlled in the scope of 0.005-0.015 % by weight.Aluminium (Al) mainly adds as deoxidant element, realize complete deoxidation, its content requirement is more than 0.01 % by weight, but too high aluminium will affect the welding property of steel and coating adhesion and uneconomical, therefore, Al content is chosen as 0.01-0.08 % by weight and is advisable.Niobium (Nb) main fixed interval (FI) C atom, titanium (Ti) mainly fixed interval (FI) atom N, makes interstitial atom be removed, obtains pure ferrite matrix.
Described slab can adopt the known method preparing continuously cast bloom of this area to be prepared, such as can by obtaining continuously cast bloom after blast furnace ironmaking, hot metal pretreatment, converter smelting, steel ladle deoxidation, alloying furnace rear refining, LF electrically heated, RH vacuum-treat and sheet billet continuous casting as described slab of the present invention.Its condition specifically prepared is well known in the art.
In addition, in the present invention, the thickness of described slab can be about 190-205mm.
According to the present invention, described hot rolling comprises roughing and finish rolling.The start rolling temperature of described roughing can be 1190-1225 DEG C, is preferably 1200-1225 DEG C; The finishing temperature of described roughing can be 1160-1190 DEG C, is preferably 1165-1185 DEG C.In addition, the thickness of the intermediate slab after described roughing can be 33-37mm, is preferably 34-35.5mm.
In addition, the start rolling temperature of described finish rolling can be 1130-1160 DEG C, is preferably 1135-1155 DEG C; The finishing temperature of described finish rolling can be 890-940 DEG C, is preferably 905-935 DEG C; The thickness of the intermediate slab after described finish rolling can be 3-5mm, is preferably 3-4.5mm.In order to reach hot rolling roughing required for start rolling temperature, first continuously cast bloom can be heated in heater before roughing, be heated to start rolling temperature required when continuously cast bloom carries out roughing.The thickness of the intermediate slab obtained after described hot rolling is the thickness of the intermediate slab after described finish rolling here, and after namely referring to after described hot rolling that finish rolling completes.
According to the present invention, after described hot rolling and before described batching, two step coolings are carried out to the intermediate slab obtained after hot rolling, after first the intermediate slab obtained after hot rolling being cooled to 780-820 DEG C with the speed of cooling of 70-90 DEG C/s, then be cooled to the temperature of batching with the speed of cooling of 15-25 DEG C/s; Preferably, after first the intermediate slab obtained after hot rolling being cooled to 785-815 DEG C with the speed of cooling of 75-85 DEG C/s, then the temperature of batching is cooled to the speed of cooling of 18-22 DEG C/s.
According to the present invention, under preferable case, the type of cooling of the above-mentioned cooling first carried out is the cooling of ultrafast cold water, then the type of cooling of the cooling carried out is air cooling or laminar flow water cooling.More preferably, the type of cooling of the cooling first carried out is the cooling of ultrafast cold water, then the type of cooling of the cooling carried out is laminar flow water cooling.
According to the present invention, under preferable case, described in the temperature of batching be 740-765 DEG C.
According to the present invention, under preferable case, described cold rolling draft is 73-80%.
According to the present invention, under preferable case, described cold rolling after the terminal temperature of intermediate slab in described heating zone, described soaking zone, a described cooling section, described low temperature maintaining segment, described overaging section and described cooling twice section that obtain be respectively 785-815 DEG C, 865-880 DEG C, 230-265 DEG C, 285-320 DEG C, 250-275 DEG C, 80 DEG C-95 DEG C, the residence time is respectively 40-65s, 35-50s, 305-425s, 75-90s, 270-290s, 145-165s.
At this, the terminal temperature of described heating zone refer to described cold rolling after the intermediate slab that obtains enter the temperature of described soaking zone through described heating zone; The terminal temperature of described soaking zone refer to described cold rolling after the intermediate slab that obtains enter the temperature of a described cooling section through described soaking zone; The terminal temperature of a described cooling section refer to described cold rolling after the intermediate slab that obtains enter the temperature of described low temperature maintaining segment through a described cooling section; The terminal temperature of described low temperature maintaining segment refer to described cold rolling after the intermediate slab that obtains enter the temperature of described overaging section through described low temperature maintaining segment; The terminal temperature of described overaging section refer to described cold rolling after the intermediate slab that obtains enter the temperature of described cooling twice section through described overaging section; The terminal temperature of described cooling twice section refer to described cold rolling after the temperature of intermediate slab when cooling twice section enters next step process that obtain.
According to the present invention, the type of heating of described heating zone can various heating means known in the field, for the present invention, preferably adopt the heating means of flame (anaerobic heating).
According to the present invention, the type of heating of described soaking zone can various heating means known in the field, such as, can adopt the heating means of electricity consumption heating radiation pipe.
According to the present invention, the type of cooling of a described cooling section can be various method of cooling known in the field, such as can with the cooling gas of flowing, as with the jet cooling of blower fan.Cooling gas used can be usually used in the gas of jet cooling for this area, and such as, the mixed gas of nitrogen and hydrogen, wherein the volume percent of hydrogen is 2-8%.
According to the present invention, entered in this low temperature maintaining segment carry out heat temperature raising by with lower temperature by the intermediate blank of a described cooling section, type of heating can various heating means known in the field, such as, can adopt the heating means of electricity consumption heating radiation pipe.
According to the present invention, the method for the temperature of described control overaging section can be conventional temperature control method, and the such as method of the temperature of described control overaging section is that electricity consumption heating radiation pipe heats overaging section and/or adopts gas blower to lower the temperature.
According to the present invention, the type of cooling of described cooling twice section can be various method of cooling known in the field, such as above-mentioned jet cooling.
According to the present invention, the unit elongation of described polishing is 0.3-0.8%, and under preferable case, the unit elongation of described polishing is 0.4-0.7%, is more preferably 0.4-0.5%.
According to the present invention, the unit elongation of described straightening is 0.1-0.7%, and under preferable case, the unit elongation of described straightening is 0.2-0.5%, is more preferably 0.2-0.25%.
According to the present invention, by making the unit elongation of the unit elongation of described polishing and described straightening in above-mentioned scope, can have and ensure plate surface quality and the good effect of plate shape.
The present invention also provides above-mentioned preparation method the cold-rolled steel sheet prepared.
Cold-rolled steel sheet provided by the invention has excellent mechanical property, the yield strength R of described cold-rolled steel sheet
eLfor 140-180MPa, be preferably 145-175MPa; Tensile strength R
mfor 280-320MPa, be preferably 285-300MPa; Elongation after fracture A
80>=48%, be preferably 48-52%; Plastic strain ratio r
90>=3.5, be preferably 3.5-3.9; Work hardening exponent n
90>=0.25, be preferably 0.26-0.28.
The microstructure of cold-rolled steel sheet provided by the invention is ferritic structure, and ferrite grain size is more than 8.5 grades, and be preferably 8.5-9.5 level, ferrite grain size is 16-20 μm.
By method of the present invention, the yield strength R of gained cold-rolled steel sheet can be controlled
eLwithin the scope of 140-180MPa and tensile strength R
mwithin the scope of 280-320MPa, there is good forming property (elongation after fracture A simultaneously
80>=48%, plastic strain ratio r
90>=3.5, work hardening exponent n
90>=0.25), be the steel plate that one is specially adapted to automobile, the overall impact briquetting component of motorcycle field (being such as automobile front wall right side plate), there are excellent market outlook.
Below will be described the present invention by embodiment.
In following examples and comparative example, the measuring method of the mechanical property of cold-rolled steel sheet is: yield strength R
eL, tensile strength R
m, elongation after fracture A
80testing method carry out according to GBT228-2002 metallic substance tensile testing at ambient temperature; Plastic strain ratio r
90testing method carry out according to the measuring method of GBT5027-2007 metal sheet and strip plastic strain ratio (r value); Work hardening exponent n
90testing method carry out according to GBT5028-2008 metal sheet and strip tension strain hardenability value (n value) test method.
The continuous annealing unit used in following examples and comparative example comprises heating zone, soaking zone, cooling section, low temperature maintaining segment, overaging section and a cooling twice section successively.Described heating zone is that non-oxidation furnace (NOF) is heated by the straight fire of coal gas, and described soaking zone is heated by electrically heated radiator tube; A described cooling section is cooled by jet; Described low temperature maintaining segment is heated by electrically heated radiator tube; Described overaging section carries out temperature control by electricity consumption heating radiation pipe and gas blower; Described cooling twice section is cooled by jet.
In following examples and comparative example, in process for cooling, the type of cooling of the cooling first carried out is the cooling of ultrafast cold water, then the type of cooling of the cooling carried out is laminar flow water cooling.
Embodiment 1-3
The present embodiment is for illustration of cold-rolled steel sheet of the present invention and preparation method thereof.
At converter smelting, obtain continuously cast bloom of the present invention (thickness is 200mm) through LF stove Ca process, RH decarburization and continuous casting, its moiety is in table 1.This continuous casting steel billet be heated in process furnace the start rolling temperature of roughing and enter reversible roughing mills, intermediate blank after roughing enters Coil Box, make band steel toe, tail is exchanged, then finish rolling is carried out, twice cooling is carried out after finish rolling, also after namely first the intermediate slab obtained after hot rolling being quickly cooled to cooling temperature A (in table 2 referred to as cold temperature A) with speed of cooling A (in table 2 referred to as cold A), the temperature of batching is cooled to again with speed of cooling B (in table 2 referred to as cold B), then send into reeling machine to carry out batching (hot rolling technology, process for cooling and batching carries out according to the condition in table 2).Then after being cooled to room temperature (25 DEG C), according to the cold rolling and continuous annealing process shown in table 3, cold rolling and anneal is carried out to slab again, be about to the slab after batching rolls into appointed thickness on cold-rolling mill cold-reduced sheet with the cold rolling draft of specifying, and then the unit speed controlling continuous annealing machine is annealed to this cold-rolled steel sheet, described continuous annealing is successively through heating zone (NOF), soaking zone (RTH), a cooling section (GJS), low temperature maintaining segment (LTH), overaging section section (OAS) and cooling twice section (FCS), then polishing and straightening is carried out according to the technique in table 3 again after being cooled to room temperature.The mechanical property of the cold-rolled steel sheet finally obtained and the data of microstructure are in table 4, and the photo of its microstructure is shown in Fig. 1-3 respectively.
Comparative example 1
According to the method described in embodiment 1, described unlike, at converter smelting, different with the moiety of the continuously cast bloom that continuous casting obtains through LF stove Ca process, RH decarburization, be shown in Table 1, the performance test results obtaining steel plate is shown in Table 4, and Fig. 4 is shown in by the photo of its microstructure.
Comparative example 2
According to the method described in embodiment 1, difference is, the speed of cooling A in process for cooling is 65 DEG C/s, and the performance test results obtaining steel plate is shown in Table 4, and Fig. 5 is shown in by the photo of its microstructure.
Comparative example 3
According to the method described in embodiment 1, difference is, the cold rolling draft taked in cold-rolling process is 62%, and the thickness rolled into is 1.5mm, and the performance test results obtaining steel plate is shown in Table 4, and Fig. 6 is shown in by the photo of its microstructure.
Comparative example 4
According to the method described in embodiment 1, difference is, the control difference (specifically as shown in table 3) of continuous annealing process, the performance test results obtaining steel plate is shown in Table 4, and Fig. 7 is shown in by the photo of its microstructure.
Table 1
Note: surplus is iron and inevitable impurity
Table 2
Table 3
Table 4
Note :-
* 1represent that tension specimen testing process sample breaks in advance, n value and r value cannot be measured;-
* 2represent and be organized as non-perfect recrystallization tissue, grain fineness number and grain-size cannot be measured.
Can be found out by the data in table 1-4, adopt preparation method of the present invention, can yield strength R be obtained
eLfor 140-180MPa, tensile strength R
mfor 280-320MPa, elongation after fracture A
80>=48%, plastic strain ratio r
90>=3.5, work hardening exponent n
90>=0.25, and microstructure is the ferritic structure of 100%, ferrite grain size is more than 8.5 grades, ferrite grain size be 16-20 μm the excellent and cold-rolled steel sheet that plastic strain ratio is high of forming property, be particularly suitable for the preparation of automobile, the overall impact briquetting component of motorcycle field.On the other hand, although comparative example 4 obtains higher intensity, its forming property is obviously poor, is difficult to use in the preparation of automobile, the overall impact briquetting component of motorcycle field; Although comparative example 1-3 obtains the intensity suitable with the embodiment of the present application 1-3, its forming property is also obviously poor, is difficult to use in the preparation of automobile, the overall impact briquetting component of motorcycle field.
More than describe the preferred embodiment of the present invention in detail; but the present invention is not limited to the detail in above-mentioned embodiment, within the scope of technical conceive of the present invention; can carry out multiple simple variant to technical scheme of the present invention, these simple variant all belong to protection scope of the present invention.
It should be noted that in addition, each the concrete technical characteristic described in above-mentioned embodiment, in reconcilable situation, can be combined by any suitable mode,
In order to avoid unnecessary repetition, the present invention illustrates no longer separately to various possible array mode.
In addition, also can carry out arbitrary combination between various different embodiment of the present invention, as long as it is without prejudice to thought of the present invention, it should be considered as content disclosed in this invention equally.
Claims (10)
1. a preparation method for cold-rolled steel sheet, the method comprises: by slab successively through hot rolling, batch, cold rolling, annealing, polishing and straightening, it is characterized in that,
After described hot rolling and before described batching, after first the intermediate slab obtained after hot rolling being cooled to 780-820 DEG C with the speed of cooling of 70-90 DEG C/s, then be cooled to the temperature of batching with the speed of cooling of 15-25 DEG C/s;
Described temperature of batching is 730-770 DEG C;
Described cold rolling draft is 75-85%;
The mode of described annealing is continuous annealing, in the process of described annealing, the intermediate slab obtained after cold rolling is successively through heating zone, soaking zone, a cooling section, low temperature maintaining segment, overaging section and cooling twice section, described cold rolling after the intermediate slab that obtains in described heating zone, described soaking zone, a described cooling section, described low temperature maintaining segment, terminal temperature in described overaging section and described cooling twice section is respectively 770-820 DEG C, 850-880 DEG C, 210-300 DEG C, 250-340 DEG C, 200-290 DEG C, less than 100 DEG C, the residence time is respectively 30-80s, 30-60s, 260-480s, 60-100s, 240-300s, 120-180s,
Consisting of of described slab: C:0.001-0.005 % by weight, Si :≤0.03 % by weight, Mn:0.1-0.3 % by weight, P:0.005-0.015 % by weight, S:0.005-0.015 % by weight, Ti:0.4-0.9 % by weight, Nb:0.005-0.03 % by weight, Al:0.01-0.08 % by weight, surplus is Fe and inevitable impurity.
2. preparation method according to claim 1, wherein, after described hot rolling and before described batching, after first the intermediate slab obtained after hot rolling being cooled to 785-815 DEG C with the speed of cooling of 75-85 DEG C/s, then be cooled to the temperature of batching with the speed of cooling of 18-22 DEG C/s.
3. preparation method according to claim 1, wherein, described in the temperature of batching be 740-765 DEG C.
4. preparation method according to claim 1, wherein, described cold rolling draft is 75-80%.
5. preparation method according to claim 1, wherein, described cold rolling after the terminal temperature of intermediate slab in described heating zone, described soaking zone, a described cooling section, described low temperature maintaining segment, described overaging section and described cooling twice section that obtain be respectively 785-815 DEG C, 865-880 DEG C, 230-265 DEG C, 285-320 DEG C, 250-275 DEG C, 80 DEG C-95 DEG C, the residence time is respectively 40-65s, 35-50s, 305-425s, 75-90s, 270-290s, 145-165s.
6. preparation method according to claim 1, wherein, consisting of of described slab: C:0.002-0.004 % by weight, Si:0.01-0.02 % by weight, Mn:0.1-0.25 % by weight, P:0.005-0.012 % by weight, S:0.005-0.012 % by weight, Ti:0.6-0.9 % by weight, Nb:0.01-0.025 % by weight, Al:0.03-0.07 % by weight, surplus is Fe and inevitable impurity.
7. method according to claim 1, wherein, described hot rolling comprises roughing and finish rolling; The start rolling temperature of described roughing is 1190-1225 DEG C, and the finishing temperature of described roughing is 1160-1190 DEG C; The start rolling temperature of described finish rolling is 1130-1160 DEG C, and the finishing temperature of described finish rolling is 890-940 DEG C.
8. preparation method according to claim 1, wherein, the unit elongation of described polishing is 0.3-0.8%; The unit elongation of described straightening is 0.1-0.7%.
9. according to cold-rolled steel sheet prepared by the preparation method in claim 1-8 described in any one.
10. cold-rolled steel sheet according to claim 9, wherein, the yield strength R of described cold-rolled steel sheet
eLfor 140-180MPa, tensile strength R
mfor 280-320MPa, elongation after fracture A
80>=48%, plastic strain ratio r
90>=3.5, work hardening exponent n
90>=0.25.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005154906A (en) * | 2000-02-29 | 2005-06-16 | Jfe Steel Kk | High tensile strength cold-rolled steel sheet having excellent strain age hardening property, and its production method |
| CN101348883A (en) * | 2008-09-11 | 2009-01-21 | 北京科技大学 | Niobium and titanium composite added ultra-low carbon baking hardening steel plate and manufacturing method thereof |
| CN101956133A (en) * | 2010-10-29 | 2011-01-26 | 攀钢集团钢铁钒钛股份有限公司 | Low-yield strength anti-ageing continuous annealing cold-roll steel sheet and production method thereof |
| CN102912226A (en) * | 2012-10-17 | 2013-02-06 | 首钢总公司 | Secondary work brittleness resistant DC06 automotive steel and production method thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2312009A1 (en) * | 2000-06-20 | 2011-04-20 | JFE Steel Corporation | Steel sheet and method for manufacturing the same |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005154906A (en) * | 2000-02-29 | 2005-06-16 | Jfe Steel Kk | High tensile strength cold-rolled steel sheet having excellent strain age hardening property, and its production method |
| CN101348883A (en) * | 2008-09-11 | 2009-01-21 | 北京科技大学 | Niobium and titanium composite added ultra-low carbon baking hardening steel plate and manufacturing method thereof |
| CN101956133A (en) * | 2010-10-29 | 2011-01-26 | 攀钢集团钢铁钒钛股份有限公司 | Low-yield strength anti-ageing continuous annealing cold-roll steel sheet and production method thereof |
| CN102912226A (en) * | 2012-10-17 | 2013-02-06 | 首钢总公司 | Secondary work brittleness resistant DC06 automotive steel and production method thereof |
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