CN111690871B - Hot-rolled steel plate for cold-rolled electro-galvanized steel plate and manufacturing method - Google Patents
Hot-rolled steel plate for cold-rolled electro-galvanized steel plate and manufacturing method Download PDFInfo
- Publication number
- CN111690871B CN111690871B CN201910187468.9A CN201910187468A CN111690871B CN 111690871 B CN111690871 B CN 111690871B CN 201910187468 A CN201910187468 A CN 201910187468A CN 111690871 B CN111690871 B CN 111690871B
- Authority
- CN
- China
- Prior art keywords
- hot
- rolling
- equal
- steel plate
- rolled
- 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.)
- Active
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 126
- 239000010959 steel Substances 0.000 title claims abstract description 126
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 27
- 229910001335 Galvanized steel Inorganic materials 0.000 title claims abstract description 21
- 239000008397 galvanized steel Substances 0.000 title claims abstract description 21
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 61
- 229910052742 iron Inorganic materials 0.000 claims abstract description 29
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 12
- 229910052717 sulfur Inorganic materials 0.000 claims abstract description 12
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 11
- 229910052748 manganese Inorganic materials 0.000 claims abstract description 11
- 239000000126 substance Substances 0.000 claims abstract description 11
- 229910052698 phosphorus Inorganic materials 0.000 claims abstract description 10
- 239000012535 impurity Substances 0.000 claims abstract description 9
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 9
- 238000005096 rolling process Methods 0.000 claims description 66
- 238000009749 continuous casting Methods 0.000 claims description 24
- 238000001816 cooling Methods 0.000 claims description 19
- 238000005098 hot rolling Methods 0.000 claims description 19
- 238000000034 method Methods 0.000 claims description 17
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 11
- 229910000859 α-Fe Inorganic materials 0.000 claims description 10
- 238000001953 recrystallisation Methods 0.000 claims description 5
- 238000005266 casting Methods 0.000 claims description 4
- 229910001562 pearlite Inorganic materials 0.000 claims description 4
- 229910001566 austenite Inorganic materials 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 description 14
- 239000011572 manganese Substances 0.000 description 11
- 230000009286 beneficial effect Effects 0.000 description 7
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 5
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 5
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 5
- 230000007547 defect Effects 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 239000010703 silicon Substances 0.000 description 5
- 239000011593 sulfur Substances 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 4
- 238000013461 design Methods 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 239000006104 solid solution Substances 0.000 description 4
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 3
- 239000003245 coal Substances 0.000 description 3
- 239000010960 cold rolled steel Substances 0.000 description 3
- 238000005265 energy consumption Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 239000011574 phosphorus Substances 0.000 description 3
- 238000007670 refining Methods 0.000 description 3
- 238000009628 steelmaking Methods 0.000 description 3
- 239000000758 substrate Substances 0.000 description 3
- 229910000655 Killed steel Inorganic materials 0.000 description 2
- 238000003723 Smelting Methods 0.000 description 2
- 230000002411 adverse Effects 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 238000007664 blowing Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000004973 liquid crystal related substance Substances 0.000 description 2
- 238000005554 pickling Methods 0.000 description 2
- 238000005728 strengthening Methods 0.000 description 2
- 238000009864 tensile test Methods 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 229910000521 B alloy Inorganic materials 0.000 description 1
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 1
- 229910001069 Ti alloy Inorganic materials 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 238000005097 cold rolling Methods 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000006477 desulfuration reaction Methods 0.000 description 1
- 230000023556 desulfurization Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000005246 galvanizing Methods 0.000 description 1
- 238000011031 large-scale manufacturing process Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 238000002161 passivation Methods 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 238000004080 punching Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000010079 rubber tapping Methods 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000000844 transformation Methods 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
- 229910001845 yogo sapphire Inorganic materials 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- 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
- C21D8/0263—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment following hot rolling
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—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
Landscapes
- 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 Sheet Steel (AREA)
Abstract
The invention discloses a hot rolled steel plate for a cold-rolled electro-galvanized steel plate and a manufacturing method thereof, and mainly solves the technical problems of high surface quality and high manufacturing cost of the existing hot rolled steel plate for the cold-rolled electro-galvanized steel plate. The invention provides a hot rolled steel plate for a cold-rolled electro-galvanized steel plate, which comprises the following chemical components in percentage by weight: c: 0.04-0.06%, Si is less than or equal to 0.03%, Mn: 0.12-0.22%, P is less than or equal to 0.025%, S is less than or equal to 0.015%, N is less than or equal to 0.0040%, Al: 0.020-0.060%, and the balance of iron and inevitable impurities. Elongation after fracture A of hot rolled steel plate with thickness of 2.3-4.5 mm50mm40-60%, the thickness of the iron scale on the upper surface of the hot-rolled steel plate is less than or equal to 4 microns, and the thickness of the iron scale on the lower surface of the hot-rolled steel plate is less than or equal to 4 microns. The hot rolled steel plate has low production cost and is suitable for producing the cold-rolled electro-galvanized steel plate for high-surface household appliances.
Description
Technical Field
The invention relates to a hot-rolled steel plate, in particular to a hot-rolled steel plate for a cold-rolled electro-galvanized steel plate and a manufacturing method thereof, and particularly relates to a hot-rolled steel plate for a cold-rolled electro-galvanized steel plate, which meets the requirements of high-surface household appliance steel and is made of aluminum killed steel, belonging to the technical field of iron-based alloy.
Background
The cold-rolled electro-galvanized steel plate has good corrosion resistance, processability, weldability and paintability, and is mainly used in the industries of automobiles, household appliances, electronics, light industry and the like. The cold-rolled electro-galvanized steel sheet in China is mainly applied to the fields of high-end household appliances and automobiles, but the cold-rolled electro-galvanized steel sheet of high-end varieties still needs to be imported in large quantity, wherein the cold-rolled electro-galvanized steel sheet comprises the steel for the high-surface household appliances. In most of the production lines of the cold-rolled electrogalvanized steel sheets in China, the requirements of the steel sheets on the hot-rolled steel sheets are very strict, the requirements of the common hot continuous rolling mill for producing the hot-rolled steel sheets are difficult to meet, and the cold-rolled electrogalvanized steel sheets manufactured in Japan and Korea are widely used for the steel for high-surface household appliances.
The cold-rolled electro-galvanized steel plate in the steel for the high-surface household appliances is mainly used for Office Automation (OA) products, such as paper feeding boxes of printers and copiers, has no visible stripes on naked eyes, belongs to a fingerprint resistant plate, and has more strict no visible defects after being polished compared with the requirements of automobiles.
Since the plated layer of the cold-rolled electrogalvanized steel sheet is thin, there is specificity of amplifying the defects of the hot-rolled steel sheet, and the hot-rolled steel sheet used for producing the cold-rolled electrogalvanized steel sheet is required to have high surface quality.
The Chinese patent application with application publication number CN104805352A discloses a production method of a cold-rolled steel plate for electrogalvanizing, steel is smelted according to components, and the specific process steps are as follows: (1) pretreating molten iron; (2) smelting in a converter; (3) an alloy fine tuning station; (4) refining in an RH furnace; (5) continuous casting; (6) hot rolling; (7) coiling; (8) cold rolling; (9) continuous annealing; (10) leveling; according to the invention, the components in the steel are accurately controlled, and the production process of the cold-rolled steel plate for electrogalvanizing is combined to obtain the cold-rolled steel plate with the yield strength of 150-240 MPa, the tensile strength higher than 270MPa and the elongation rate greater than 37%, which can meet the deep drawing forming requirement, has good plate shape and surface quality (above FC), and can meet the requirements of electrogalvanizing and subsequent passivation fingerprint resistance treatment; the material of the invention adopts a high furnace-out temperature of 1170-1200 ℃ and a high coiling temperature of 695-725 ℃, which are not beneficial to controlling the iron scale. Meanwhile, an edge heater is required to be put into the hot rolling finish rolling inlet. An edge heater is not arranged at a hot rolling finish rolling inlet of a common hot continuous rolling production line, and the equipment requirement is higher. Meanwhile, the invention has higher energy consumption, is not beneficial to economic production and has high production cost.
The Chinese patent application with application publication number CN105483547A discloses a deep-drawing fingerprint-resistant electro-galvanized sheet for household appliances, which comprises the following chemical components in percentage by weight: c: 0.0040-0.0080%, Si is less than or equal to 0.020%, Mn: 0.10-0.23%, P is less than or equal to 0.020%, S is less than or equal to 0.015%, sol.Al: 0.020-0.060%, N is not more than 0.0050%, Ti: 0.04-0.11%, B: 0.0020 to 0.0045 percent, and the balance of Fe and inevitable impurities. The electro-galvanized plate adopts ultra-low carbon steel, and trace Ti and B alloy are added, so that the electro-galvanized plate has excellent deep drawing processing performance, the deformation height of a punched hole is not more than 0.1mm compared with an undeformed flat steel plate, the technical problem of difficult assembly after punching of the electro-galvanized plate at present is solved, and the requirements of various complex deep drawing deformation and assembly of washing machine shells, liquid crystal display television back plates and the like manufactured by household appliances are met. The material adopts an ultra-low carbon design, has higher cost, mainly aims to meet the deep drawing deformation requirements of household appliances manufacturing washing machine shells, liquid crystal television back plates and the like, has no regulation on the surface quality of hot rolled steel plates, and cannot meet the surface quality requirements of high-end cold-rolled electro-galvanized steel plates for household appliances.
The existing hot rolled steel plate for producing the cold-rolled electro-galvanized steel plate has high manufacturing difficulty, the surface quality of the hot rolled steel plate is low, the surface defect rate of the cold-rolled electro-galvanized steel plate produced by using the hot rolled steel plate is high, and the ever-increasing requirements of high-end household appliance markets can not be met.
Disclosure of Invention
The invention aims to provide a hot rolled steel plate for a cold-rolled electrogalvanized steel plate and a manufacturing method thereof, mainly solving the technical problems of poor high surface quality and high manufacturing cost of the existing hot rolled steel plate for the cold-rolled electrogalvanized steel plate.
The invention adopts the technical scheme that a hot rolled steel plate for a cold-rolled electro-galvanized steel plate comprises the following chemical components in percentage by weight: c: 0.04-0.06%, Si is less than or equal to 0.03%, Mn: 0.12-0.22%, P is less than or equal to 0.025%, S is less than or equal to 0.015%, N is less than or equal to 0.0040%, Al: 0.020-0.060%, and the balance of iron and inevitable impurities.
The metallographic structure of the hot-rolled steel plate is ferrite and pearlite, and the grain size of the ferrite in the metallographic structure is 7-8 grades; longitudinal lower yield strength R of hot rolled steel plate with thickness of 2.3-4.5 mmeLIs 180 to 280MPa, tensile strength Rm290-360 MPa, elongation after break A50mm40-60%, the thickness of the iron scale on the upper surface of the hot-rolled steel plate is less than or equal to 4 microns, and the thickness of the iron scale on the lower surface of the hot-rolled steel plate is less than or equal to 4 microns.
The hot-rolled steel plate has excellent processing performance, high surface quality and low production cost, and is suitable for producing the cold-rolled electro-galvanized steel plate for high-surface household appliances.
The reason why the chemical composition weight percentage of the hot rolled steel sheet for the cold rolled electrogalvanized steel sheet according to the present invention is limited to the above range is as follows:
carbon: carbon is the cheapest and most effective solid solution strengthening element, increases C content, increases strength, but reduces plasticity and formability of steel and is detrimental to weldability. Therefore, in consideration of economy and comprehensive performance, the control range of the C content is set to be 0.04-0.06%.
Silicon: silicon suitably increases the strength of steel by solid solution strengthening in steel. The Si content is too high, the iron scale on the surface of the steel plate is not easy to remove, microcracks pressed by the oxide are easily formed on the surface, and the steel plate is easy to crack in the cold forming process as a crack source. Meanwhile, the higher silicon content in the steel substrate adversely affects the electrogalvanizing. As the silicon content in the steel substrate increases, the silicon is oxidized to form SiO2The content of (A) is increased, which affects the effect of the subsequent pickling process, and if there is residual SiO on the surface of the steel sheet after pickling2Resulting in deterioration of the plating adhesion. In order to ensure the high surface quality of the base material, the Si content is strictly controlled, and Si is set to be less than or equal to 0.03 percent.
Manganese: manganese strengthens ferrite and also increases the strength of the electrogalvanized substrate by solid solution. In addition, the addition of manganese to steel prevents embrittlement of steel due to sulfur during hot working, but as the Mn content of the electrogalvanized sheet increases, the workability gradually decreases. Meanwhile, Mn is an easily segregated element, and the high content of Mn can increase the center segregation of the continuous casting billet, thereby being not beneficial to steel welding. Therefore, the Mn content is set to be 0.12 to 0.22%.
Sulfur and phosphorus: too high sulfur and phosphorus adversely affect the toughness and plasticity of the material, while too low sulfur and Lin increase the cost of desulfurization and dephosphorization in steel making. The invention sets S less than or equal to 0.015 percent and P less than or equal to 0.025 percent.
Nitrogen: the plasticity and the toughness of the material are seriously deteriorated when the nitrogen content is too high, and the N is set to be less than or equal to 0.0040 percent.
Aluminum: the aluminum plays a role in deoxidation in the present invention, and is a strong oxidizing forming element, and oxygen in steel is removed as Al2O3 in steel making. Too high an aluminum content can lead to excessive Al formation2O3And the pouring nozzle is easy to block during continuous casting. The invention sets the Al content to be 0.020-0.060%.
A method for manufacturing a hot rolled steel sheet for a cold-rolled electrogalvanized steel sheet, comprising:
continuously casting molten steel to obtain a continuous casting slab, wherein the molten steel comprises the following chemical components in percentage by weight: c: 0.04-0.06%, Si is less than or equal to 0.03%, Mn: 0.12-0.22%, P is less than or equal to 0.025%, S is less than or equal to 0.015%, N is less than or equal to 0.0040%, Al: 0.020-0.060% of iron and inevitable impurities in balance;
the continuous casting plate blank is heated for 150-240 min at 1080-1120 ℃ and then is subjected to hot rolling, the hot rolling adopts a two-stage control rolling process, the rough rolling is 6-pass rolling, the rolling is carried out at the temperature above the austenite recrystallization temperature, the rough rolling finishing temperature is 960-1000 ℃, and the rough rolling descaling water pressure is more than or equal to 15 MPa; after rough rolling, controlling the thickness of the intermediate billet to be 40-45 mm; the finish rolling is 7-pass continuous rolling, the finish rolling finishing temperature is 850-890 ℃, and the finish rolling descaling water pressure is more than or equal to 15 MPa; after finish rolling, controlling the thickness of the steel plate to be 2.3-4.5 mm, adopting front-end cooling for laminar cooling, wherein the laminar cooling speed is 5-15 ℃/s, and coiling temperature is 540-580 ℃ to obtain a hot-rolled steel coil.
The hot rolling process and the control of the surface scale of the hot rolled steel plate are the technical key for realizing the invention. By calculation, the component system A of the invention3At 815 ℃ A1At 706 ℃. The hot rolling process adopted by the invention is based on the component system and the calculated phase change point, and the specific reason of the hot rolling process system adopted by the invention is as follows:
1. setting of heating temperature and heating time of continuous casting slab
And heating the continuous casting plate blank, discharging the continuous casting plate blank at a low temperature, and testing the influence of different heating temperatures on the scale so as to eliminate the residue of rough rolling scale and synthesize the factors of scale removal difficulty and surface quality. The average thickness of the iron scale at the heating temperature of 1100 ℃ is 2.5 μm, and the average thickness of the iron scale at the heating temperature of 1180 ℃ is 9.4 μm.
The heating temperature of the continuous casting slab is set to be 1100 +/-20 ℃, and the heating time is 150-240 min. Compared with the high temperature of 1180 +/-20 ℃ of SPHC with the same specification, the interface morphology of the hot-rolled strip steel oxide scale and a matrix can be obviously optimized, and the thickness of the hot-rolled strip steel plate surface oxide scale can be controlled to be below 4 mu m.
The heating temperature is reduced, so that the energy consumption can be reduced, the iron burning loss of the continuous casting plate blank can be reduced, and the method has the characteristics of low production cost and the like. The statistical data shows that the standard coal can be saved by 0.03Kg per ton of steel when the heating temperature of the continuous casting slab is reduced by 1 ℃, and the iron burning loss of the continuous casting slab can be reduced by 0.08%; compared with the SPHC with the same specification, the heating temperature of the continuous casting slab is reduced by 80 ℃, 2.4Kg of standard coal can be saved per ton of steel, and the burning loss of iron of the continuous casting slab is reduced by 64 Kg.
2. Setting of roughing finishing temperature and intermediate slab thickness
Grain refinement is started in the rough rolling process, and the grains are refined by recrystallization through strain energy release generated in the rolling reduction. In order to ensure the finish rolling temperature, the rough rolling inlet temperature is increased as much as possible, but the surface quality of the plate coil cannot be ensured due to the overhigh rough rolling inlet temperature, and the temperature is reduced according to the condition; comprehensively considering, the invention sets the rough rolling finishing temperature to be 960-1000 ℃ and controls the thickness of the intermediate billet to be 40-45 mm.
3. Setting of roughing descaling water pressure
According to the survey and analysis of the surface defects of the cold-rolled electrogalvanized steel plate, the surface defects of the cold-rolled electrogalvanized steel plate mainly come from the hot-rolled steel plate serving as a production raw material of the cold-rolled electrogalvanized steel plate, scale marks generated in a continuous casting plate blank heating furnace in the process of the hot-rolled steel plate and left after secondary scale removal are residual scales, and the on-line detection of a hot continuous rolling large-scale production line is difficult to find; through years of experimental research, the applicant finds that rough rolling descaling is beneficial to eliminating rough rolling secondary oxide scale; comprehensively considered, the pressure of rough rolling descaling water is set to be more than or equal to 15 MPa.
4. Setting of finishing descaling water pressure
The cooling water between the finishing mill frames mainly has the function of reducing the temperature of the surface of the strip steel, thereby reducing the damage of the strip steel to an oxide film on the surface of a working roll. The finish rolling descaling water is beneficial to improving the descaling effect of the iron scale on the surface of the finish rolling strip steel. Comprehensively considered, the pressure of finish rolling descaling water is set to be more than or equal to 15 MPa.
5. Setting of finish Rolling finishing temperature
Hot rolling process, based on austenitic rolling, the finishing temperature of which must be higher than the temperature at which dynamic recrystallization occurs and controlled above the ferrite transformation temperature, i.e. Fe-Fe3Above the GS line of the phase C diagram. In addition, in order to prevent the mixed crystal area of the head, the tail and the edge from being too large, the use of a user is influenced. Comprehensively considered, the finish rolling finishing temperature is set to be 850-.
6. Method of laminar cooling after finish rolling and setting of laminar cooling rate
Considering the temperature difference of the head part, the tail part and the middle part of the hot-rolled steel plate, the structure and the performance uniformity of the hot-rolled steel plate meet the design requirements; by comprehensive consideration, the laminar cooling adopts a front-section cooling mode, which is beneficial to cooling firstly in the laminar cooling process, so that the generation of iron scales in the laminar cooling process is reduced, and the laminar cooling speed is 5-15 ℃/s.
7. Setting of coiling temperature in Hot Rolling
The reduced hot rolling coiling temperature is beneficial to reducing the generation of the tertiary iron scale of finish rolling. Combining the component system of the invention, the invention sets the hot rolling coiling temperature to be 540-.
The metallographic structure of the hot-rolled steel plate produced by the method is ferrite and pearlite, and the grain size of the ferrite in the metallographic structure is 7-8 grades; longitudinal lower yield strength R of hot rolled steel plate with thickness of 2.3-4.5 mmeL180 to 280MPa, tensile strength Rm290-360 MPa, elongation after break A50mm40-60%, the thickness of the iron scale on the upper surface of the hot-rolled steel plate is less than or equal to 4 microns, and the thickness of the iron scale on the lower surface of the hot-rolled steel plate is less than or equal to 4 microns.
The hot rolled steel plate produced by the method has excellent processing performance, high surface quality of the hot rolled steel plate and low production cost, and is suitable for producing the cold-rolled electro-galvanized steel plate for high-surface household appliances.
Compared with the prior art, the invention has the following positive effects: 1. the invention adopts solid solution elements of carbon and manganese for reinforcement, strictly controls phosphorus and sulfur impurity elements of molten steel, and ensures that the component design meets the requirement of stable performance of the electrogalvanizing hot-rolled steel plate of the aluminum killed steel for high-end household appliances. 2. The component system of the invention combines with proper steelmaking, continuous casting and hot rolling process design to produce the electro-galvanizing hot-rolled raw plate hot-rolled strip steel with the thickness of iron scale below 4 mu m, thereby ensuring that the surface quality meets the requirements. 3. The invention adopts low-temperature tapping, can reduce energy consumption and slab iron burning loss, and has the characteristics of low production cost and the like. Compared with the same specification SPHC, the heating temperature is reduced, 2.4Kg of standard coal can be saved per ton of steel, and the burning loss of the slab iron is reduced by 64 Kg. 4. The hot rolled steel plate meets the requirements of electrogalvanizing manufacturing enterprises on the mechanical property and the technological property of the high-end electrogalvanizing steel hot rolled plate for household appliances, and fills the industrial blank.
Drawings
FIG. 1 is a photograph showing a metallographic structure of a hot rolled steel sheet according to example 1 of the present invention.
Detailed Description
The present invention is further described with reference to examples 1 to 4, which are shown in tables 1 to 3.
Table 1 shows the chemical composition (in weight%) of the steels of the examples of the invention, the balance being Fe and unavoidable impurities.
Table 1 chemical composition of the steels of the examples of the invention, in units: and (4) weight percentage.
Molten steel meeting the requirements of chemical components is obtained by smelting in a converter, and Ar blowing treatment is carried out on the molten steel in the refining process of an LF ladle refining furnace. And the continuous casting adopts the whole-process Ar blowing protection casting, and the molten steel is cast into a continuous casting slab.
And after the continuous casting plate blank is heated by a heating furnace, rolling the continuous casting plate blank on a hot continuous rolling mill, controlling the rolling by a rough rolling mill and a finish rolling continuous rolling mill unit, cooling the front section by laminar cooling, and then coiling to obtain a hot rolled steel coil. The thickness of the finished hot rolled steel plate is 2.3-4.5 mm, and the control parameters of the hot rolling process are shown in table 2.
TABLE 2 Hot Rolling Process control parameters of the inventive examples
Referring to fig. 1, the metallographic structure of the hot-rolled steel plate produced by the method is ferrite + pearlite, and the grain size of the ferrite in the metallographic structure is 7-8 grades; longitudinal lower yield strength R of hot rolled steel sheeteL180 to 280MPa, tensile strength Rm290-360 MPa, elongation after break A50mm40-60%, the thickness of the iron scale on the upper surface of the hot-rolled steel plate is less than or equal to 4 microns, and the thickness of the iron scale on the lower surface of the hot-rolled steel plate is less than or equal to 4 microns.
The hot rolled steel plate produced by the method has excellent processing performance, high surface quality of the hot rolled steel plate and low production cost, and is suitable for producing the cold-rolled electro-galvanized steel plate for high-surface household appliances.
The hot rolled steel sheet obtained by the invention is subjected to a tensile test according to GB/T228.1-2010 part 1: room temperature test method "was used for tensile test, and the mechanical properties are shown in Table 3.
TABLE 3 mechanical properties of hot rolled steel sheets according to examples of the present invention and thickness of scale on the surface of the steel sheets
In addition to the above embodiments, the present invention may have other embodiments. All technical solutions formed by adopting equivalent substitutions or equivalent transformations fall within the protection scope of the claims of the present invention.
Claims (4)
1. A hot rolled steel plate for a cold-rolled electro-galvanized steel plate comprises the following chemical components in percentage by weight: c: 0.04-0.06%, Si is less than or equal to 0.03%, Mn: 0.12-0.22%, P is less than or equal to 0.025%, S is less than or equal to 0.015%, N is less than or equal to 0.0040%, Al: 0.020-0.060% of iron and inevitable impurities in balance; the metallographic structure of the hot-rolled steel plate is ferrite and pearlite, and the grain size of the ferrite in the metallographic structure is 7-8 grades; the thickness of the oxide scale on the upper surface of the hot-rolled steel plate is less than or equal to 4 mu m, and the thickness of the oxide scale on the lower surface of the hot-rolled steel plate is less than or equal to 4 mu m; a method for manufacturing a hot-rolled steel sheet for a cold-rolled electrogalvanized steel sheet, characterized by comprising the steps of:
continuously casting molten steel to obtain a continuous casting slab, wherein the molten steel comprises the following chemical components in percentage by weight: c: 0.04-0.06%, Si is less than or equal to 0.03%, Mn: 0.12-0.22%, P is less than or equal to 0.025%, S is less than or equal to 0.015%, N is less than or equal to 0.0040%, Al: 0.020-0.060% of iron and inevitable impurities in balance;
the continuous casting plate blank is heated for 150-240 min at 1080-1120 ℃ and then is subjected to hot rolling, the hot rolling adopts a two-stage control rolling process, the rough rolling is 6-pass rolling, the rolling is carried out at the temperature above the austenite recrystallization temperature, the rough rolling finishing temperature is 960-1000 ℃, and the rough rolling descaling water pressure is more than or equal to 15 MPa; after rough rolling, controlling the thickness of the intermediate billet to be 40-45 mm; the finish rolling is 7-pass continuous rolling, the finish rolling finishing temperature is 850-890 ℃, and the finish rolling descaling water pressure is more than or equal to 15 MPa; and after finish rolling, performing front-stage cooling by adopting laminar cooling, wherein the laminar cooling speed is 5-15 ℃/s, and the hot-rolled steel coil is obtained by coiling when the coiling temperature is 540-580 ℃.
2. The hot-rolled steel sheet for a cold-rolled electrogalvanized steel sheet according to claim 1, wherein the hot-rolled steel sheet has a yield strength R in the longitudinal direction of 2.3 to 4.5mmeL180 to 280MPa, tensile strength Rm290-360 MPa, elongation after break A50mm40 to 60 percent.
3. A method for manufacturing a hot rolled steel plate for a cold-rolled electrogalvanized steel plate is characterized by comprising the following steps:
continuously casting molten steel to obtain a continuous casting slab, wherein the molten steel comprises the following chemical components in percentage by weight: c: 0.04-0.06%, Si is less than or equal to 0.03%, Mn: 0.12-0.22%, P is less than or equal to 0.025%, S is less than or equal to 0.015%, N is less than or equal to 0.0040%, Al: 0.020-0.060% of iron and inevitable impurities in balance;
the continuous casting plate blank is heated for 150-240 min at 1080-1120 ℃ and then is subjected to hot rolling, the hot rolling adopts a two-stage control rolling process, the rough rolling is 6-pass rolling, the rolling is carried out at the temperature above the austenite recrystallization temperature, the rough rolling finishing temperature is 960-1000 ℃, and the rough rolling descaling water pressure is more than or equal to 15 MPa; after rough rolling, controlling the thickness of the intermediate billet to be 40-45 mm; the finish rolling is 7-pass continuous rolling, the finish rolling finishing temperature is 850-890 ℃, and the finish rolling descaling water pressure is more than or equal to 15 MPa; and after finish rolling, performing front-stage cooling by adopting laminar cooling, wherein the laminar cooling speed is 5-15 ℃/s, and the hot-rolled steel coil is obtained by coiling when the coiling temperature is 540-580 ℃.
4. The method of manufacturing a hot rolled steel sheet for a cold rolled electrogalvanized steel sheet according to claim 3, wherein a thickness of the steel sheet after the hot rolling finish rolling is controlled to be 2.3 to 4.5 mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910187468.9A CN111690871B (en) | 2019-03-13 | 2019-03-13 | Hot-rolled steel plate for cold-rolled electro-galvanized steel plate and manufacturing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910187468.9A CN111690871B (en) | 2019-03-13 | 2019-03-13 | Hot-rolled steel plate for cold-rolled electro-galvanized steel plate and manufacturing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111690871A CN111690871A (en) | 2020-09-22 |
| CN111690871B true CN111690871B (en) | 2021-11-16 |
Family
ID=72474763
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910187468.9A Active CN111690871B (en) | 2019-03-13 | 2019-03-13 | Hot-rolled steel plate for cold-rolled electro-galvanized steel plate and manufacturing method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111690871B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115505817A (en) * | 2021-06-07 | 2022-12-23 | 上海梅山钢铁股份有限公司 | A kind of production method of thin thickness low-carbon B-containing hot-rolled steel plate |
| CN115491583B (en) * | 2021-06-18 | 2023-09-05 | 上海梅山钢铁股份有限公司 | Ultra-deep drawing cold-rolled hot-dip aluminum-zinc steel plate and manufacturing method thereof |
| CN115418546A (en) * | 2022-07-26 | 2022-12-02 | 新疆八一钢铁股份有限公司 | Production method of hot-rolled coiled material B265K for cold-formed socket steel pipe |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02194146A (en) * | 1988-10-24 | 1990-07-31 | Nippon Steel Corp | High-strength hot-rolled steel sheet with excellent cold workability and surface quality and its manufacturing method |
| CN102676918A (en) * | 2012-06-13 | 2012-09-19 | 鞍钢股份有限公司 | Hot rolled steel plate for hot-dip galvanizing pot and production method thereof |
| CN102851600A (en) * | 2011-06-28 | 2013-01-02 | 鞍钢股份有限公司 | X65 pipeline steel with excellent low-temperature toughness and manufacturing method thereof |
| CN103320689A (en) * | 2012-03-22 | 2013-09-25 | 上海梅山钢铁股份有限公司 | Aluminum-zinc hot plating deep drawing steel with thick gauge of more than 1.2 mm, and manufacturing method thereof |
| JP2014031538A (en) * | 2012-08-02 | 2014-02-20 | Nippon Steel & Sumitomo Metal | Hot-rolled steel sheet and method for producing the same |
| CN103695764A (en) * | 2012-09-27 | 2014-04-02 | 上海梅山钢铁股份有限公司 | Cold-rolling hot-dipping steel plate used for liquid-crystal module backboard and production method of the steel plate |
| CN103882305A (en) * | 2012-12-21 | 2014-06-25 | 鞍钢股份有限公司 | Ultrahigh-strength ship plate resistant to low-temperature strain aging brittleness and production method thereof |
| CN104805352A (en) * | 2015-05-07 | 2015-07-29 | 马钢(集团)控股有限公司 | Production method of cold-rolled steel plate for electro-galvanization |
| CN105506469A (en) * | 2014-09-25 | 2016-04-20 | 上海梅山钢铁股份有限公司 | Anti-stamping-distortion aluminum-and-zinc-plated steel and production method thereof |
| EP3239323A1 (en) * | 2014-12-22 | 2017-11-01 | Posco | Hot-rolled steel sheet for high strength galvanized steel sheet, having excellent surface quality, and method for producing same |
| CN107419180A (en) * | 2017-08-16 | 2017-12-01 | 马鞍山钢铁股份有限公司 | A kind of yield strength >=250MPa electrogalvanizing cold-rolled steel sheet and production method |
| CN107964624A (en) * | 2016-10-19 | 2018-04-27 | 上海梅山钢铁股份有限公司 | A kind of yield strength 500MPa level structure steel and preparation method thereof |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102021476A (en) * | 2009-09-18 | 2011-04-20 | 鞍钢股份有限公司 | A low-cost acid-resistant pipeline steel hot-rolled coil and its manufacturing method |
| CN102409245A (en) * | 2011-11-16 | 2012-04-11 | 济南钢铁股份有限公司 | Hot-rolled dual-phase steel sheet with high-elongation flange performance and manufacturing method thereof |
| JP6477020B2 (en) * | 2015-02-27 | 2019-03-06 | 新日鐵住金株式会社 | Hot rolled steel sheet and manufacturing method thereof |
-
2019
- 2019-03-13 CN CN201910187468.9A patent/CN111690871B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02194146A (en) * | 1988-10-24 | 1990-07-31 | Nippon Steel Corp | High-strength hot-rolled steel sheet with excellent cold workability and surface quality and its manufacturing method |
| CN102851600A (en) * | 2011-06-28 | 2013-01-02 | 鞍钢股份有限公司 | X65 pipeline steel with excellent low-temperature toughness and manufacturing method thereof |
| CN103320689A (en) * | 2012-03-22 | 2013-09-25 | 上海梅山钢铁股份有限公司 | Aluminum-zinc hot plating deep drawing steel with thick gauge of more than 1.2 mm, and manufacturing method thereof |
| CN102676918A (en) * | 2012-06-13 | 2012-09-19 | 鞍钢股份有限公司 | Hot rolled steel plate for hot-dip galvanizing pot and production method thereof |
| JP2014031538A (en) * | 2012-08-02 | 2014-02-20 | Nippon Steel & Sumitomo Metal | Hot-rolled steel sheet and method for producing the same |
| CN103695764A (en) * | 2012-09-27 | 2014-04-02 | 上海梅山钢铁股份有限公司 | Cold-rolling hot-dipping steel plate used for liquid-crystal module backboard and production method of the steel plate |
| CN103882305A (en) * | 2012-12-21 | 2014-06-25 | 鞍钢股份有限公司 | Ultrahigh-strength ship plate resistant to low-temperature strain aging brittleness and production method thereof |
| CN105506469A (en) * | 2014-09-25 | 2016-04-20 | 上海梅山钢铁股份有限公司 | Anti-stamping-distortion aluminum-and-zinc-plated steel and production method thereof |
| EP3239323A1 (en) * | 2014-12-22 | 2017-11-01 | Posco | Hot-rolled steel sheet for high strength galvanized steel sheet, having excellent surface quality, and method for producing same |
| CN104805352A (en) * | 2015-05-07 | 2015-07-29 | 马钢(集团)控股有限公司 | Production method of cold-rolled steel plate for electro-galvanization |
| CN107964624A (en) * | 2016-10-19 | 2018-04-27 | 上海梅山钢铁股份有限公司 | A kind of yield strength 500MPa level structure steel and preparation method thereof |
| CN107419180A (en) * | 2017-08-16 | 2017-12-01 | 马鞍山钢铁股份有限公司 | A kind of yield strength >=250MPa electrogalvanizing cold-rolled steel sheet and production method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111690871A (en) | 2020-09-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104946969B (en) | Hot-rolled pickled steel plate for air conditioner compressor housings and manufacturing method thereof | |
| CN107419180B (en) | A kind of the electrogalvanizing cold-rolled steel sheet and production method of yield strength >=250MPa | |
| CN103627957B (en) | The production method of CR4 hot dip galvanizing automobile plate steel | |
| CN108796375A (en) | A kind of tensile strength 1000MPa grades of hot-dip galvanized high-strength steels and its minimizing production method | |
| CN113481430B (en) | 800 MPa-grade boron-containing hot-dip galvanized dual-phase steel with enhanced hole expansion performance and production method thereof | |
| CN104805352A (en) | Production method of cold-rolled steel plate for electro-galvanization | |
| CN102094149A (en) | Niobium-containing high-strength hot-galvanized steel plate and production method thereof | |
| CN111455259A (en) | Hot-rolled pickled steel plate for electrogalvanizing and production method thereof | |
| CN110273108A (en) | A kind of deep-draw grade electrogalvanizing hot rolling acid-cleaning steel plate and its production method | |
| CN107475625B (en) | A kind of the electrogalvanizing cold-rolled steel sheet and production method of yield strength >=350MPa | |
| CN111961789B (en) | Structural-grade color-coated base material hot-dip galvanized steel plate for thin-specification steel products and manufacturing method thereof | |
| CN110551939A (en) | Hot-dip galvanized steel plate with yield strength of 320MPa and production method thereof | |
| CN111690871B (en) | Hot-rolled steel plate for cold-rolled electro-galvanized steel plate and manufacturing method | |
| CN105525214A (en) | Cold rolling hard tinning steel plate and production method thereof | |
| TWI424068B (en) | Extremely thin steel sheet and manufacturing method thereof | |
| CN112553537A (en) | Cold-rolled hot-dip galvanized steel sheet with yield strength of 240MPa and manufacturing method thereof | |
| CN114438413A (en) | Hot-dip galvanized high-strength structural steel with yield strength of 340MPa and production method thereof | |
| CN102639740B (en) | Steel sheet for cans and method for producing same | |
| CN114480972A (en) | Thin-specification Ni-free weathering steel produced based on CSP process and production method thereof | |
| CN110629000A (en) | Cold-rolled hot-dip galvanized steel sheet with yield strength of 280MPa and manufacturing method thereof | |
| CN110714165B (en) | Cold-rolled sheet for 320 MPa-level household appliance panel and production method thereof | |
| CN113025909A (en) | Hot-rolled pickled plate for refrigerator compressor shell and production method thereof | |
| CN101775540A (en) | Anti-aging steel plate with high machinability and manufacturing method thereof | |
| CN104651715A (en) | Cold-rolled steel plate, preparation method of cold-rolled steel plate, hot-dip galvanized steel plate, and preparation method of hot-dip galvanized steel plate | |
| CN111926252B (en) | Hot-rolled pickled steel plate for deep drawing and production method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |