CN113106335A - 800 MPa-grade high-strength weather-resistant girder steel belt and preparation method thereof - Google Patents
800 MPa-grade high-strength weather-resistant girder steel belt and preparation method thereof Download PDFInfo
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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
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
- B21B45/0203—Cooling
- B21B45/0209—Cooling devices, e.g. using gaseous coolants
- B21B45/0215—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes
- B21B45/0218—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes for strips, sheets, or plates
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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
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
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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
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
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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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/20—Ferrous alloys, e.g. steel alloys containing chromium with copper
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
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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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/28—Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium
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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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
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Abstract
The invention relates to an 800 MPa-grade high-strength weather-proof girder steel belt and a preparation method thereof, wherein the girder steel belt comprises the following chemical components in percentage by weight: 0.03 to 0.10 percent of C, 0.10 to 0.30 percent of Si, 1.60 to 1.90 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.005 percent of S, 0.010 to 0.050 percent of Als, 0.2 to 0.4 percent of Cu, 0.30 to 0.5 percent of Cr, 0.08 to 0.20 percent of Mo, 0.070 to 0.14 percent of Ti, less than or equal to 0.0060 percent of N, and the balance of Fe and inevitable residual elements. The preparation method comprises the working procedures of slab heating, rough rolling, finish rolling, controlled cooling and slow cooling after rolling; in the slab heating process, the air-fuel ratio of the heating furnace is 0.9-1.2, the heating time is 170-350min, the slab discharging temperature is 1240-1300 ℃, and the soaking time in the heating furnace is 30-50 min. The girder steel strip produced by the invention has good obdurability matching, small residual stress of a finished product, excellent plate shape control, excellent corrosion resistance and obvious cost advantage.
Description
Technical Field
The invention relates to a girder steel belt, in particular to an 800MPa grade high-strength weather-resistant girder steel belt and a preparation method thereof, belonging to the technical field of ferrous metallurgy.
Background
At present, under the increasingly strict environmental protection pressure, the special vehicle is used as an important transportation tool for supporting national economic development, so that how to reduce the dead weight of the vehicle body and reduce the exhaust emission becomes a key problem which people pay more and more attention to. In order to meet the requirements of new environmental protection, a new generation of special vehicle needs to have the characteristics of low vehicle body dead weight, high loading efficiency and green energy conservation, but the strength of the traditional girder steel which is used as the main raw material of the special vehicle at present is generally below 700MPa, the vehicle body has heavy self weight, the loading efficiency is not high, the corrosion resistance is not realized, and the special vehicle cannot be applied to the fields of special vehicles such as environmental sanitation, mining and chemical engineering. Therefore, with the upgrading of special vehicles, the market urgently needs a girder steel with higher strength and good corrosion resistance to replace the traditional girder steel.
The patent with the publication number of CN1043134918B discloses 'a P segregation-free weathering steel hot-rolled thin strip and a manufacturing method thereof', wherein the weathering steel comprises the following alloy components in percentage by weight: c: 0.07 to 0.12 percent of Si: 0.30-0.60%, Mn: 0.40-0.55%, S is less than or equal to 0.02%, P: 0.05-0.16%, Cr: 0.60% -0.80%, Ni: 0.03 to 0.11 percent, Cu: 0.20 to 0.50 percent of Al, less than or equal to 0.046 percent of Al, less than or equal to 0.003 percent of B, and the balance of Fe and inevitable impurities. The manufacturing method related to the patent is only suitable for a thin strip casting and rolling production line, can only produce 1.2-3.0mm ultrathin specification strip steel, has the tensile strength of a product below 550MPa, has thin specification and low strength, and limits the market application of the product.
The patent with the publication number of CN106947913B discloses 'a high-strength high-toughness hot-rolled weather-resistant steel plate and a preparation method thereof', which comprises the following chemical components in percentage by weight: c: 0.05-0.10%, Si: 0.10-0.50%, Mn: 1.00% -1.30%, P: less than or equal to 0.015%, S: less than or equal to 0.010 percent, Cr:0.30% -0.70%, Ni: 0.10-0.40%, Cu: 0.25-0.50%, Al: 0.020% -0.050%, Nb: 0.010-0.040%, Ti: 0.010-0.030 percent, and the balance of Fe and inevitable impurity elements. The steel plate has high low-temperature impact property, cold processing property and good atmospheric corrosion resistance, but expensive alloy elements such as high Cr, Ni, Nb and the like are added in the component design, so that the production cost is high, the tensile strength of the steel is below 600MPa, and the strength level is limited.
CN 105543666B discloses 'an automobile girder steel with 960MPa yield strength and a production method thereof', which comprises the following chemical components: c: 0.12% -0.14%, Si: 0.15% -0.35%, Mn: 1.2% -1.5%, Nb: 0.02% -0.04%, Mo: 0.3% -0.5%, V: 0.08-0.15%, Ti: 0.01-0.04%, Al: 0.01-0.06%, Cr: 0.4-0.6%, B is 0.0015-0.0025%, P: less than or equal to 0.02 percent, S: less than or equal to 0.01 percent, N: less than or equal to 0.008 percent, and the balance of Fe and inevitable impurities. The invention adopts the conventional hot continuous rolling, quenching after rolling and high-temperature tempering processes to obtain the tempered martensite structure, the process flow is long, the cost is higher, and the delivery cycle is limited by the productivity. In addition, the steel does not contain corrosion-resistant elements such as Cr, Cu, Ni and the like, and cannot be safely used in special environments such as humidity, acid and alkali and the like, so that the application of the product in the field of special vehicles is limited.
Disclosure of Invention
The invention aims to solve the technical problem of providing an 800MPa grade high-strength weather-resistant crossbeam steel strip which has the advantages of good obdurability matching, small residual stress of a finished product, excellent plate shape control and excellent corrosion resistance, and also provides a preparation method of the 800MPa grade high-strength weather-resistant crossbeam steel strip.
The technical scheme for solving the technical problems is as follows:
an 800 MPa-grade high-strength weather-resistant crossbeam steel belt comprises the following chemical components in percentage by weight: 0.03 to 0.10 percent of C, 0.10 to 0.30 percent of Si, 1.60 to 1.90 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.005 percent of S, 0.010 to 0.050 percent of Als, 0.2 to 0.4 percent of Cu, 0.30 to 0.5 percent of Cr, 0.08 to 0.20 percent of Mo, 0.070 to 0.14 percent of Ti, less than or equal to 0.0060 percent of N, and the balance of Fe and inevitable residual elements.
The 800 MPa-grade high-strength weather-proof girder steel strip has the thickness range of 1.5-16.0mm, the yield strength 741-786MPa, the tensile strength 899-1083MPa, the elongation of 17.4-21.8 percent and the full-scale impact energy of 139.8-165.1J at-20 ℃.
The invention mainly bases on the design of components:
c: carbon is an inexpensive alloy element, plays a role in interstitial solid solution strengthening in the present invention, and contains a certain amount of carbon to ensure the strength of the steel, but too high carbon content causes deterioration of toughness and weldability of the steel, and therefore, the C content is preferably controlled to 0.03wt% to 0.10wt% in the present invention.
Si: silicon plays roles of deoxidation and solid solution strengthening in steel, but too high Si increases the brittleness of the steel and reduces the impact toughness, and too high Si is easy to generate fayalite Fe at high temperature2SiO4The pinned iron scale is difficult to remove through high-pressure descaling, so that the iron scale is pressed in the next rolling process, and the surface quality is affected. Therefore, Si of the present invention is preferably controlled to 0.10wt% to 0.30 wt%.
Mn: manganese mainly plays a role in solid solution strengthening in steel, and excessive Mn is easy to form serious center segregation, damage the uniformity of the structure and influence the impact toughness of the steel. Therefore, the Mn in the present invention is preferably controlled to 1.60 wt% to 1.90 wt%.
P and S: as a harmful element in steel, sulfur is preferably controlled within 0.005wt% or less in combination with cost in order to ensure that the product performance should be strictly controlled. Phosphorus is coordinated with elements such as Cu, Cr and the like in steel to form a compact oxidation rust layer on the surface of the steel, so that the further corrosion of a matrix structure is prevented, but the phosphorus is an easily-segregated element, the too high phosphorus can increase the ductile-brittle transition temperature of the steel and reduce the low-temperature impact property of the steel, and the phosphorus is strictly controlled within 0.020wt% in the invention for obtaining the girder steel with excellent performance.
Al: the aluminum plays a role in deoxidation in molten steel smelting, but too high Al can form large-size Al2O3And impurities are mixed, so that the low-temperature impact property of the steel plate is reduced. Therefore, the Al content in the present invention is preferably controlled to be between 0.010wt% and 0.050 wt%.
Cu and Cr: copper and chromium are common effective corrosion-resistant elements, and a compact alpha-FeOOH oxidized embroidery layer can be formed on the surface of the steel by proportionally using Cu, Cr and P to prevent the matrix structure of the steel from being further corroded. Considering the production cost, preferably, Cu is controlled within 0.2wt% -0.4wt%, and Cr is controlled within 0.30wt% -0.5 wt%.
Mo molybdenum MoO4 generated in the contact process of steel surface and corrosive medium2-Can promote the formation of an amorphous oxide film on the surface of steel, increase the affinity of the steel for oxygen through Mo alloying and inhibit corrosive anion Cl-1Etc. to play a role in corrosion inhibition. In addition, Mo can refine the structure grains, promote the formation of acicular ferrite, and increase the low-temperature impact toughness of the steel, but too high Mo can greatly increase the alloy cost. Therefore, it is preferable that the Mo content is controlled to 0.08wt% to 0.20 wt%.
Ti: titanium is a strong carbon and nitrogen compound forming element, and is precipitated in the cooling process after rolling and during rolling to play a strengthening role. Meanwhile, a proper amount of Ti is added into the steel to form fine titanium carbonitride, so that the growth of crystal grains during heating can be effectively inhibited, and the effect of refining the crystal grains is achieved. However, too high Ti combines with N to form coarse TiN inclusions, which reduce the low temperature toughness and fatigue properties of the steel. Therefore, it is preferable that the Ti content is controlled to be between 0.070wt% and 0.14 wt%.
N: nitrogen is a harmful element in steel, and excessively high nitrogen combines with Ti to generate large-sized TiN inclusions, deteriorating formability and low-temperature impact properties of the steel. Therefore, it is preferable that the N content is controlled to be within 0.0060 wt%.
A preparation method of an 800 MPa-grade high-strength weather-resistant crossbeam steel strip comprises the working procedures of plate blank heating, rough rolling, finish rolling, controlled cooling and slow cooling after rolling; the slab comprises the following chemical components in percentage by weight: 0.03 to 0.10 percent of C, 0.10 to 0.30 percent of Si, 1.60 to 1.90 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.005 percent of S, 0.010 to 0.050 percent of Als, 0.2 to 0.4 percent of Cu, 0.30 to 0.5 percent of Cr, 0.08 to 0.20 percent of Mo, 0.070 to 0.14 percent of Ti, less than or equal to 0.0060 percent of N, and the balance of Fe and inevitable residual elements.
The preparation method of the 800 MPa-grade high-strength weather-resistant girder steel strip comprises the working procedures of heating a plate blank, rough rolling, finish rolling, controlled cooling and slow cooling after rolling; in the slab heating process, the air-fuel ratio of the heating furnace is 0.9-1.2, the heating time is 170-350min, the slab discharging temperature is 1240-1300 ℃, and the soaking time in the heating furnace is 30-50 min.
In the rough rolling process, 3 + 5 passes of rough rolling are adopted, namely the R1 rack of the rough rolling is rolled for 3 passes back and forth, the R2 rack of the rough rolling is rolled for 5 passes back and forth, the reduction rate of the last two passes is controlled to be between 20% and 30%, and the accumulated reduction rate of the rough rolling is controlled to be between 65% and 90%.
In the finish rolling process, an intermediate roller way heat-insulating cover between rough rolling and finish rolling is used, the finish rolling inlet temperature is 950-.
In the cooling process, the laminar cooling adopts a front section interval cooling mode, namely odd groups of cooling water in front 10 groups of headers are opened and even groups of cooling water are closed, and sparse cooling can be formed in the front section to reduce the cooling strength and improve the shape of a finished product; laminar cooling water temperature is 20-36 ℃, cooling rate is 20-50 ℃/s, and the temperature is cooled to 580-650 ℃ for coiling.
According to the preparation method of the 800 MPa-grade high-strength weather-resistant girder steel strip, in the process of slow cooling after rolling, the steel strip is hoisted into a finished product slow cooling warehouse within 10min after being off-line, and is stacked in the slow cooling warehouse in a centralized manner, and the slow cooling time is not less than 48 h.
The heating process is improved in the slab heating procedure, so that the problem of copper brittleness of the slab in the heating and rolling processes is avoided, and the main basis is as follows:
cu is added into the high-strength weather-resistant girder steel, is a corrosion-resistant element, and is acted on the surface of the steel together with elements such as Cr, P, Mo and the like to form a compact oxidation rust layer so as to prevent the matrix structure of the steel from being further corroded. However, if the heating process is inappropriate after adding Cu to the steel, Cu precipitates during heating and rolling to cause network cracks (i.e., copper embrittlement), thereby deteriorating the surface properties of the steel. In order to prevent the copper brittleness problem during heating and rolling, on one hand, the alloy elements in the steel are ensured to be fully dissolved in solution, and simultaneously, the structure is prevented from being coarse, and the tapping temperature of the beam steel slab is preferably controlled between 1240 ℃ and 1300 ℃. On the other hand, the atmosphere of the heating furnace, the tapping temperature and the residence time in the high-temperature section need to be strictly controlled. Wherein the heating furnace adopts a reducing atmosphere, and the air-fuel ratio is preferably controlled between 0.9 and 1.2. The heating time is too short, alloy elements cannot be fully dissolved in a solid solution, the grain structure of the steel is coarse when the heating time is too long, the structural property of the steel is deteriorated, and meanwhile Cu is easy to precipitate along the grain boundary in the long-time heating process in a high-temperature period, so that the surface property of the steel is deteriorated. Therefore, the invention preferably relates to the total heating time of the girder steel plate blank in the heating furnace of 170-350min, and the soaking time of 30-50 min.
The invention adopts a front section interval cooling mode in the controlled cooling process, so that the produced girder steel has good structure performance and can ensure better plate shape, and the main basis is as follows:
the laminar cooling system of the Handover 2250 hot continuous rolling production line has 22 groups of cooling headers in total, when a front section interval cooling mode is adopted, cooling water of odd groups of headers in the front 10 groups of headers is turned on, and cooling water of even groups of headers is turned off, so that a sparse cooling mode is formed at the front section to reduce cooling strength, improve side-spraying blowing effect, improve transverse cooling uniformity of strip steel, and facilitate relieving residual stress of high-strength steel edges. And a conventional front section cooling mode is adopted, cooling water of a front section collecting pipe is continuously opened, so that accumulated water on the surface of the strip steel is easily caused to influence the side spraying and sweeping effect, the transverse cooling of the strip steel is uneven, and the shape of a finished product is influenced. Therefore, the use of the front stage gap cooling mode in the controlled cooling enables the improvement of the finished plate shape.
The invention has the beneficial effects that:
1) the invention relates to a girder steel, which adopts a Ni-free design, obtains good corrosion resistance through reasonable collocation of Cr, Cu, P and Mo under the condition of not adding noble Ni alloy, and has a corrosion rate lower than 2.3 g/(m) for 72 hours under the same corrosion condition2h) While the corrosion rate of the common low alloy Q345B is 5.0 g/(m)2h) The above. Meanwhile, the heating process of the plate blank is improved, so that the problem of copper brittleness of the plate blank in the heating and rolling processes is avoided.
2) A front-section segmented interval cooling process is adopted in the controlled cooling process, a sparse cooling mode is formed in the front 10 groups of laminar cooling systems to reduce the cooling strength, the transverse cooling uniformity of the strip steel is improved, the residual stress of the edge part is relieved, and the edge shape of a finished product is improved.
3) The tensile strength of the corrosion-resistant beam steel produced by the method is more than 800MPa, the low-temperature impact property at minus 20 ℃ is more than 120J, the corrosion-resistant beam steel has good obdurability matching and good corrosion resistance in humid and moderate acid-base environments, and can be safely used in the fields of special vehicles such as sanitation, mining and chemical engineering.
The specific implementation mode is as follows:
the invention relates to a 800MPa grade high-strength weather-proof girder steel belt, which comprises the following chemical components in percentage by weight: 0.03 to 0.10 percent of C, 0.10 to 0.30 percent of Si, 1.60 to 1.90 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.005 percent of S, 0.010 to 0.050 percent of Als, 0.2 to 0.4 percent of Cu, 0.30 to 0.5 percent of Cr, 0.08 to 0.20 percent of Mo, 0.070 to 0.14 percent of Ti, less than or equal to 0.0060 percent of N, and the balance of Fe and inevitable residual elements. The production method comprises the working procedures of slab heating, rough rolling, finish rolling, controlled cooling and slow cooling after rolling;
and a slab heating process, wherein the heating furnace adopts reducing atmosphere, the air-fuel ratio is 0.9-1.2, the total slab heating time is 170-350min, the slab discharging temperature is 1240-1300 ℃, and the soaking time in the heating furnace is 30-50 min.
And the rolling procedure comprises rough rolling and finish rolling, wherein the rough rolling procedure adopts 3 + 5-pass rolling, namely, a rough rolling R1 rack performs 3-pass back-and-forth rolling, a rough rolling R2 rack performs 5-pass back-and-forth rolling, the final two-pass reduction rate is controlled to be between 20% and 30%, the accumulated reduction rate of the rough rolling is controlled to be between 65% and 90%, and an intermediate roller way heat-insulating cover between the rough rolling and the finish rolling is used. And a finish rolling procedure, wherein the inlet temperature of finish rolling is 950-.
And controlling a cooling process, wherein 22 groups of cooling headers are counted in a laminar cooling system of the 2250 hot continuous rolling production line, a front section interval cooling mode is adopted for laminar cooling, namely, cooling water of odd groups of headers in front 10 groups of headers is opened, cooling water of even groups of headers is closed, and opening and closing of cooling water of rear sections of headers are autonomously controlled by a known secondary model of a rolling mill. Laminar cooling water temperature is 20-36 ℃, cooling rate is 20-50 ℃/s, and the temperature is cooled to 580-650 ℃ for coiling.
The present invention will be described in further detail with reference to specific examples.
Examples 1-8 were produced in accordance with the above-described embodiment, and the chemical composition in weight percent of the steel strip is shown in table 1.
TABLE 1 chemical composition control (unit: wt%)
The parameters of the girder steel slab heating process related to the invention are shown in table 2.
TABLE 2 heating Process parameters of the slabs
The main parameters of the girder steel rolling process related to the invention are shown in table 3.
TABLE 3 Main parameters of the Rolling Process
Note: the reduction ratios of the last 2 passes of rough rolling are listed in Table 3, for example, "22/28" where "/" is preceded by the reduction ratio of the last pass of rough rolling and "/" is followed by the reduction ratio of the last pass of rough rolling.
The high-strength corrosion-resistant girder steel produced according to the invention has the following mechanical properties: yield strength 741-786MPa, tensile strength 899-1083MPa, elongation between 17.4% and 21.8%, and full-scale impact energy between 139.8J and 165.1J at-20 ℃, as detailed in Table 4.
TABLE 4 mechanical Properties measurements
Note: 1. in Table 4, the tensile test piece and the bending test piece were transverse test pieces.
2. D is the bending indenter diameter and a is the bending specimen thickness.
3. The longitudinal test sample is taken in the impact test, the test sample is prepared according to the standard size, when the size of the test sample is insufficient, the test sample can be replaced by the small-size test sample of 7.5mm and 5mm, the corresponding impact energy standard is converted by 75 percent and 50 percent, and the impact test can not be carried out on the thickness below 6 mm.
The steel girder sample plates and the comparative sample plates of examples 1 to 8 were subjected to accelerated corrosion for 72 hours in an artificial salt spray environment (corrosion medium: 5% NaCl solution dissolved in 18.2 M.OMEGA.. multidot.cm deionized water, pH 6.8, test temperature 35 ℃ C.), and the corrosion conditions of the different sample plates were compared, as shown in Table 5.
TABLE 5 salt spray Corrosion test conditions
Note: the relative corrosion rate was based on the corrosion rate of Q355B.
As can be seen from Table 5, the corrosion rates of the examples are from 1.865 to 2.234 g/(m)2h) The corrosion rate of the comparative sample Q355B is 5.385 g/(m)2h) The 610L and 700L corrosion rates are 5.032 g/(m)2h) And 4.896 g/(m)2h) The invention relates to high-strength weather-proof girder steel which shows good corrosion resistance compared with a comparative steel grade.
Claims (8)
1. An 800 MPa-grade high-strength weather-resistant crossbeam steel belt is characterized in that: the weight percentage of the chemical components is as follows: 0.03 to 0.10 percent of C, 0.10 to 0.30 percent of Si, 1.60 to 1.90 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.005 percent of S, 0.010 to 0.050 percent of Als, 0.2 to 0.4 percent of Cu, 0.30 to 0.5 percent of Cr, 0.08 to 0.20 percent of Mo, 0.070 to 0.14 percent of Ti, less than or equal to 0.0060 percent of N, and the balance of Fe and inevitable residual elements.
2. The 800MPa grade high strength weather resistant girder steel strip of claim 1, wherein: the thickness range of the girder steel strip is 1.5-16.0mm, the yield strength 741-786MPa, the tensile strength 899-1083MPa, the elongation between 17.4-21.8 percent and the full-scale impact energy at-20 ℃ between 139.8-165.1J.
3. A preparation method of an 800 MPa-grade high-strength weather-resistant crossbeam steel strip comprises the working procedures of plate blank heating, rough rolling, finish rolling, controlled cooling and slow cooling after rolling; the method is characterized in that: the slab comprises the following chemical components in percentage by weight: 0.03 to 0.10 percent of C, 0.10 to 0.30 percent of Si, 1.60 to 1.90 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.005 percent of S, 0.010 to 0.050 percent of Als, 0.2 to 0.4 percent of Cu, 0.30 to 0.5 percent of Cr, 0.08 to 0.20 percent of Mo, 0.070 to 0.14 percent of Ti, less than or equal to 0.0060 percent of N, and the balance of Fe and inevitable residual elements.
4. The preparation method of the 800MPa grade high-strength weather-proof girder steel strip according to claim 3, characterized in that: the cooling process is controlled, the odd groups of cooling water in the 10 groups of collecting pipes before laminar cooling are started, the even groups of cooling water are closed, the laminar cooling water temperature is 20-36 ℃, the cooling rate is 20-50 ℃/s, and the cooling is carried out to 580-650 ℃ for coiling.
5. The preparation method of the 800MPa grade high-strength weather-proof girder steel strip according to claim 3, characterized in that: in the slab heating process, the air-fuel ratio of the heating furnace is 0.9-1.2, the heating time is 170-350min, the slab discharging temperature is 1240-1300 ℃, and the soaking time in the heating furnace is 30-50 min.
6. The preparation method of the 800MPa grade high-strength weather-proof girder steel strip according to claim 3, characterized in that: the rough rolling procedure adopts 3 + 5 passes of rolling, the reduction rate of the last two passes is controlled between 20% and 30%, and the accumulated reduction rate of the rough rolling is controlled between 65% and 90%.
7. The preparation method of the 800MPa grade high-strength weather-proof girder steel strip according to claim 3, characterized in that: the finish rolling procedure comprises the steps of putting an intermediate roller way heat-insulating cover, controlling the finish rolling inlet temperature to be 950-1050 ℃, controlling the finish rolling accumulated reduction rate to be 60-80% and controlling the finish rolling temperature to be 840-910 ℃.
8. The preparation method of the 800MPa grade high-strength weather-proof girder steel strip according to claim 3, characterized in that: and in the step of slow cooling after rolling, the steel coil is lifted into a finished product slow cooling warehouse within 10min after being off line, and is stacked in the slow cooling warehouse in a centralized manner, wherein the slow cooling time is not less than 48 h.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113770174A (en) * | 2021-08-13 | 2021-12-10 | 邯郸钢铁集团有限责任公司 | High-strength and high-toughness steel plate shape control method for engineering machinery |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105316578A (en) * | 2014-07-29 | 2016-02-10 | 上海梅山钢铁股份有限公司 | Automobile beam steel which is low in carbon equivalent, easy to weld and more than 750Mpa in yield strength and fabrication method thereof |
| CN105838996A (en) * | 2016-04-28 | 2016-08-10 | 河北钢铁股份有限公司承德分公司 | 800MPa-grade high-strength and weather-proof steel plate and production method thereof |
| EP3235923A1 (en) * | 2014-12-19 | 2017-10-25 | Baoshan Iron & Steel Co., Ltd. | High-strength steel with yield strength of 800 mpa and production method therefor |
| CN109402508A (en) * | 2018-11-12 | 2019-03-01 | 东北大学 | A kind of low-carbon microalloyed Q690 grade high-strength weathering steel and preparation method thereof |
-
2021
- 2021-03-11 CN CN202110267939.4A patent/CN113106335A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105316578A (en) * | 2014-07-29 | 2016-02-10 | 上海梅山钢铁股份有限公司 | Automobile beam steel which is low in carbon equivalent, easy to weld and more than 750Mpa in yield strength and fabrication method thereof |
| EP3235923A1 (en) * | 2014-12-19 | 2017-10-25 | Baoshan Iron & Steel Co., Ltd. | High-strength steel with yield strength of 800 mpa and production method therefor |
| CN105838996A (en) * | 2016-04-28 | 2016-08-10 | 河北钢铁股份有限公司承德分公司 | 800MPa-grade high-strength and weather-proof steel plate and production method thereof |
| CN109402508A (en) * | 2018-11-12 | 2019-03-01 | 东北大学 | A kind of low-carbon microalloyed Q690 grade high-strength weathering steel and preparation method thereof |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113770174A (en) * | 2021-08-13 | 2021-12-10 | 邯郸钢铁集团有限责任公司 | High-strength and high-toughness steel plate shape control method for engineering machinery |
| CN113770174B (en) * | 2021-08-13 | 2023-09-05 | 邯郸钢铁集团有限责任公司 | Steel plate shape control method for high-strength and high-toughness engineering machinery |
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Application publication date: 20210713 |