CN109182898A - A kind of yield strength 650MPa grades of acid-cleaning plates and its production method - Google Patents
A kind of yield strength 650MPa grades of acid-cleaning plates and its production method Download PDFInfo
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- CN109182898A CN109182898A CN201811022739.7A CN201811022739A CN109182898A CN 109182898 A CN109182898 A CN 109182898A CN 201811022739 A CN201811022739 A CN 201811022739A CN 109182898 A CN109182898 A CN 109182898A
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- acid
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- pickling
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—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
- C21D8/0221—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
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
-
- 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
- C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
- C23G1/08—Iron or steel
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/005—Ferrite
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/009—Pearlite
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Sheet Steel (AREA)
Abstract
The present invention provides a kind of yield strength 650MPa grades of acid-cleaning plates and its production methods, formula is C 0.05~0.07%, Mn 1.60~1.80%, Als 0.03~0.06%, Ti 0.09~0.10%, Si≤0.05%, Nb 0.045~0.055%, S≤0.008%, P≤0.015%, N≤0.004%, O≤0.003%, remaining is iron and inevitable impurity.Compared with prior art, the present invention has good processing performance and good surface quality by control formula and production technology, 650MPa grades of acid-cleaning plates of yield strength of production.12.5~13 grades of its grain size, microscopic structure are as follows: ferrite+contain a small amount of carbide+a small amount of fine pearlite.Its yield strength representative value is 680MPa, and tensile strength representative value 770MPa, elongation percentage representative value is 19%.
Description
Technical field
The invention belongs to High-Strength Low-Alloy rolling controlled and cooling controlled steel technical fields, and the vehicle structure after being mainly used for pickling is used
Steel.More particularly to a kind of yield strength 650MPa grades of acid-cleaning plates and its production method.
Background technique
High-strength vehicle structure pickled plate, the defects of always existing scale on surface, point, roll marks, restrict
The promotion and application of high-strength vehicle structure pickled plate.The main reason for causing this status is high alloy at setting up separately
Meter, causes in course of hot rolling that rolling load is big, roll pitted skin is serious, while production stability is not strong, and performance and surface quality obtain
Less than guarantee.
Summary of the invention
The purpose of the present invention is to provide a kind of yield strength 650MPa grades of acid-cleaning plates, are designed using the ingredient of low N, O, into
Row Ti microalloying has good processing performance and good surface quality.
Another object of the present invention is to provide a kind of production methods of yield strength 650MPa grades of acid-cleaning plates, according to steel
Formula controls N, O content using the duplex technique of LF+RH furnace, improves Ti utilization rate;It is designed, is made using reasonable coiling temperature
Ti reaches best precipitation effect after the cooling period.12.5~13 grades of the acid-cleaning plate grain size of production, microscopic structure are as follows: ferrite+
Contain a small amount of carbide+a small amount of fine pearlite.Yield strength representative value is 680MPa, tensile strength representative value 770MPa, is extended
Rate representative value is 19%.
Specific technical solution of the present invention is as follows:
A kind of yield strength 650MPa grades of acid-cleaning plates provided by the invention, contain following weight percent element: C 0.05
~0.07%, Mn 1.60~1.80%, Als 0.03~0.06%, Ti 0.09~0.10%, Si≤0.05%, Nb 0.045
~0.055%, S≤0.008%, P≤0.015%, N≤0.004%, O≤0.003%, remaining for iron and inevitably it is miscellaneous
Matter.
A kind of production method of yield strength 650MPa grades of acid-cleaning plates provided by the invention, comprising the following steps: converter smelting
-- -- -- -- -- -- section cooling -- batches -- pickling to hot continuous rolling to continuous casting to RH application of vacuum to the refining of LF furnace to ladle argon-blown for refining.
Further, in the hot continuous rolling step, the tapping temperature of heating furnace is 1210~1260 DEG C, and soaking time is many
In 40min;
Further, in the hot continuous rolling step, roughing roll 6~8 passages, per pass deflection 10~35% it
Between, for the deflection of last three passage between 20~35%, roughing finishing temperature is 1082~1095 DEG C;
Further, in the hot continuous rolling step, entry temperature at finishing is 1000~1080 DEG C;The first and second passage of finish rolling
Reduction ratio be not less than 40%, last percentage pass reduction be not more than 12%, finish rolling finishing temperature be 840~900 DEG C;Using
The thermomechanical controlled rolling technique of TMCP does not allow any rack not apply deflection and empty mistake, and hot rolled thickness specification 1.2~
6.0mm。
Further, the section cooling, cooling rate are greater than 25 DEG C/s;
Further, described to batch step, coiling temperature is 560~650 DEG C.
Further, the pickling carries out pickling using continuous pickling line, and pickling temperature is 70~80 DEG C, pickling speed
60~150m/min;
Further, in pickling, the free acid strength of each acid tank is respectively as follows: 1# acid tank and dissociates acid strength for 30~70g/
L, 2# acid tank dissociate acid strength for 100~150g/L, and 3# acid tank dissociates acid strength for 145~185g/L.
The acid-cleaning plate of above method production, 12.5~13 grades of grain size, microscopic structure are as follows: ferrite+contain a small amount of carbonization
Object+a small amount of fine pearlite.The yield strength representative value of 650MPa grades of acid-cleaning plates of its yield strength is 680MPa, and tensile strength is typical
Value 770MPa, elongation percentage representative value are 19%.
It in design producing method, is designed according to formula and properties of product, in order to be dissolved microalloy sufficiently, by heating temperature
At 1210~1260 DEG C, soaking time is no less than 40 minutes for degree control.The distribution of roughing rolling pass: 6~8 passage roughing are used.
Deflection requires between 10~35% per pass.For fining austenite grains, the deflection requirement of last 3 passage of roughing
Greater than 20%;To avoid roll-force excessive, the deflection of every a time of last 3 passage of roughing requires to be not more than 35%.Essence
It rolls rolling pass distribution: using hot continuous rolling.1000~1080 DEG C of rolling temperature of the first passage of finish rolling.It is required that finish rolling first,
The reduction ratio of two passages is not less than 40%, last pass deformation is not more than 12%.Finish rolling finishing temperature is not higher than 900 DEG C,
Not less than 840 DEG C.Using the thermomechanical controlled rolling technique of TMCP, any rack is not allowed not apply deflection and empty mistake.Essence
Implement section cooling after rolling immediately.Without other specially increased technological measures between section cooling and the last a time of finish rolling.
Cooling rate is greater than 25 DEG C/s.After cooling starts, it is not allow for interrupting cooling before the temperature miss the mark coiling temperature of steel
Behavior.After section cooling, coiled sheet is coiled into through coiling machine.560~650 DEG C of coiling temperature range.In acid cleaning process,
Pickling temperature is 70~80 DEG C, 60~150m/min of pickling speed;The free acid strength of each acid tank is respectively as follows: 1# acid tank free acid
Liquid concentration be 30~70g/L, 2# acid tank dissociate acid strength be 100~150g/L, 3# acid tank dissociate acid strength be 145~
185g/L。
The present invention reaches hot rolling by the method for low silicon niobium titanium alloy and using reasonable hot rolling technology system
Stable and high-grade strip surface quality.
Compared with prior art, the present invention passes through control formula and production technology, 650MPa grades of acid of yield strength of production
Board-washing has good processing performance and good surface quality.12.5~13 grades of its grain size, microscopic structure are as follows: ferrite+
Contain a small amount of carbide+a small amount of fine pearlite.Its yield strength representative value is 680MPa, and tensile strength representative value 770MPa prolongs
Stretching rate representative value is 19%.
Detailed description of the invention
Fig. 1 yield strength 650MPa grades of acid-cleaning plate metallographic structures produced by the invention.
Specific embodiment
Embodiment 1
A kind of yield strength 650MPa grades of acid-cleaning plates, contain following weight percent element: C 0.062%, Mn1.70%,
Als 0.040%, Ti 0.097%, Si0.022%, Nb 0.048%, S 0.003%, P 0.010%, N 0.0025%, O
0.0015%, remaining is iron and inevitable impurity.
A kind of production method of yield strength 650MPa grades of acid-cleaning plates, comprising the following steps: converter smelting -- ladle is blown
-- -- -- -- -- section cooling -- batches -- pickling to hot continuous rolling to continuous casting to RH application of vacuum to the refining of LF furnace to argon.
In hot continuous rolling step, the tapping temperature of heating furnace is 1249 DEG C, soaking time 54min;Roughing rolls 6~8 passages,
Deflection is between 10~35% per pass, and between 20~35%, roughing finishing temperature is the deflection of last three passage
1090℃;Entry temperature at finishing is 1070 DEG C;The reduction ratio of the first and second passage of finish rolling is not less than 40%, last a time pressure
Rate is not more than 12%, and finish rolling finishing temperature is 881 DEG C;Using the thermomechanical controlled rolling technique of TMCP, any rack is not allowed
Deflection is not applied and empty mistake.Section cooling, 45 DEG C/s of cooling rate;Step is batched, coiling temperature is 610 DEG C.Pickling uses
Continuous pickling line carries out pickling, and pickling temperature is 74 DEG C, pickling speed 125m/min;The free acid strength difference of each acid tank
Are as follows: 1# acid tank dissociates acid strength for 56g/L, and 2# acid tank dissociates acid strength for 122g/L, and the free acid strength of 3# acid tank is
154g/L。
The chemical component and weight percent of 650MPa grades of acid-cleaning plates of embodiment 2-5 yield strength are shown in Table 1, and production technology is same
Embodiment 1, parameter are shown in Table 2, and mechanical property is shown in Table 3.
The chemical component and weight percent of 650MPa grades of acid-cleaning plates in 1 embodiment 1-5 of table
C | Mn | Als | Ti | Si | Nb | S | P | N | O | |
Embodiment 1 | 0.062% | 1.70% | 0.040% | 0.097% | 0.022% | 0.048% | 0.003% | 0.010% | 0.0025% | 0.0015% |
Embodiment 2 | 0.055% | 1.67% | 0.035% | 0.095% | 0.034% | 0.054% | 0.005% | 0.007% | 0.0034% | 0.0027% |
Embodiment 3 | 0.053% | 1.74% | 0.54% | 0.096% | 0.027% | 0.049% | 0.002% | 0.009% | 0.0021% | 0.0023% |
Embodiment 4 | 0.058% | 1.72% | 0.53% | 0.097% | 0.014% | 0.051% | 0.007% | 0.008% | 0.0012% | 0.0028% |
Embodiment 5 | 0.059% | 1.71% | 0.60% | 0.099% | 0.031% | 0.048% | 0.006% | 0.007% | 0.0018% | 0.0012% |
The processing parameter of 650MPa grades of acid-cleaning plates in 2 embodiment 1-5 of table
The performance parameter of 650MPa grades of acid-cleaning plates in 3 embodiment 1-5 of table
Yield strength 650MPa grades of acid-cleaning plates produced by the invention have good processing performance and good surface quality.
12.5~13 grades of its grain size, microscopic structure are as follows: ferrite+contain a small amount of carbide+a small amount of fine pearlite.Its yield strength allusion quotation
Offset is 680MPa, and tensile strength representative value 770MPa, elongation percentage representative value is 19%.
Claims (10)
1. a kind of yield strength 650MPa grades of acid-cleaning plates, which is characterized in that the yield strength 650MPa grades of acid-cleaning plates contain with
Lower weight percent element: C 0.05~0.07%, Mn 1.60~1.80%, Als 0.03~0.06%, Ti 0.09~
0.10%, Si≤0.05%, Nb 0.045~0.055%, S≤0.008%, P≤0.015%, N≤0.004%, O≤
0.003%, remaining is iron and inevitable impurity.
2. the production method of yield strength 650MPa grades of acid-cleaning plate described in a kind of claim 1, which is characterized in that the producer
Method is the following steps are included: converter smelting, and -- -- -- -- laminar flow is cold for continuous casting -- hot continuous rolling -- for RH application of vacuum for the refining of LF furnace for ladle argon-blown
But pickling -- is batched --.
3. production method according to claim 2, which is characterized in that in the hot continuous rolling step, heating furnace goes out furnace temperature
Degree is 1210~1260 DEG C, and soaking time is no less than 40min.
4. production method according to claim 2 or 3, which is characterized in that in the hot continuous rolling step, roughing rolling 6~8
Passage, deflection is between 10~35% per pass, and the deflection of last three passage is between 20~35%, roughing finishing temperature
It is 1082~1095 DEG C.
5. production method according to claim 2 or 3, which is characterized in that, in the hot continuous rolling step, finish rolling entrance temperature
Degree is 1000~1080 DEG C;The reduction ratio of the first and second passage of finish rolling is not less than 40%, last percentage pass reduction is not more than
12%, finish rolling finishing temperature is 840~900 DEG C.
6. production method according to claim 2, which is characterized in that the section cooling, cooling rate are greater than 25 DEG C/s.
7. production method according to claim 2, which is characterized in that described to batch step, coiling temperature is 560~650
℃。
8. production method according to claim 2, which is characterized in that the pickling carries out acid using continuous pickling line
It washes, pickling temperature is 70~80 DEG C, 60~150m/min of pickling speed.
9. the production method according to claim 2 or 8, which is characterized in that in pickling, the free acid strength difference of each acid tank
Are as follows: 1# acid tank dissociates acid strength for 30~70g/L, and the free acid strength of 2# acid tank is 100~150g/L, 3# acid tank free acid
Liquid concentration is 145~185g/L.
10. according to the described in any item production methods of claim 2-9, which is characterized in that acid-cleaning plate produced, grain size
12.5~13 grades, microscopic structure are as follows: ferrite+contain a small amount of carbide+a small amount of fine pearlite.
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CN201811022739.7A CN109182898A (en) | 2018-09-03 | 2018-09-03 | A kind of yield strength 650MPa grades of acid-cleaning plates and its production method |
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CN201811022739.7A CN109182898A (en) | 2018-09-03 | 2018-09-03 | A kind of yield strength 650MPa grades of acid-cleaning plates and its production method |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112593143A (en) * | 2020-10-28 | 2021-04-02 | 邯郸钢铁集团有限责任公司 | 800 MPa-grade low-cost steel for pickling battery bracket and production method thereof |
CN114774655A (en) * | 2022-03-29 | 2022-07-22 | 本钢板材股份有限公司 | Low-cost 600 MPa-grade hot-rolled pickled plate and preparation method thereof |
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CN101748329A (en) * | 2009-12-24 | 2010-06-23 | 马鞍山钢铁股份有限公司 | 610MPa automobile girder steel and production method thereof |
CN106868408A (en) * | 2017-03-28 | 2017-06-20 | 马钢(集团)控股有限公司 | A kind of yield strength 550MPa grades low silicon titaniferous acid-cleaning plate and preparation method thereof |
CN106967926A (en) * | 2017-03-28 | 2017-07-21 | 马钢(集团)控股有限公司 | A kind of yield strength 460MPa grades low silicon titaniferous acid-cleaning plate and preparation method thereof |
-
2018
- 2018-09-03 CN CN201811022739.7A patent/CN109182898A/en active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
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CN101748329A (en) * | 2009-12-24 | 2010-06-23 | 马鞍山钢铁股份有限公司 | 610MPa automobile girder steel and production method thereof |
CN106868408A (en) * | 2017-03-28 | 2017-06-20 | 马钢(集团)控股有限公司 | A kind of yield strength 550MPa grades low silicon titaniferous acid-cleaning plate and preparation method thereof |
CN106967926A (en) * | 2017-03-28 | 2017-07-21 | 马钢(集团)控股有限公司 | A kind of yield strength 460MPa grades low silicon titaniferous acid-cleaning plate and preparation method thereof |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112593143A (en) * | 2020-10-28 | 2021-04-02 | 邯郸钢铁集团有限责任公司 | 800 MPa-grade low-cost steel for pickling battery bracket and production method thereof |
CN112593143B (en) * | 2020-10-28 | 2022-03-25 | 邯郸钢铁集团有限责任公司 | 800 MPa-grade low-cost steel for pickling battery bracket and production method thereof |
CN114774655A (en) * | 2022-03-29 | 2022-07-22 | 本钢板材股份有限公司 | Low-cost 600 MPa-grade hot-rolled pickled plate and preparation method thereof |
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