CN115198183A - Rare earth hot rolled steel plate for 350 MPa-grade double-sided enamel after enamel and manufacturing method thereof - Google Patents
Rare earth hot rolled steel plate for 350 MPa-grade double-sided enamel after enamel and manufacturing method thereof Download PDFInfo
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
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- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
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- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
- B21B1/24—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a continuous or semi-continuous process
- B21B1/26—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a continuous or semi-continuous process by hot-rolling, e.g. Steckel hot mill
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- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/46—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting
- B21B1/463—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting in a continuous process, i.e. the cast not being cut before rolling
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/005—Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
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- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C38/00—Ferrous alloys, e.g. steel alloys
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- 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
- C23D—ENAMELLING OF, OR APPLYING A VITREOUS LAYER TO, METALS
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- C23D5/04—Coating with enamels or vitreous layers by dry methods
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Abstract
The invention relates to a rear earth hot rolled steel plate for 350MPa grade double-sided enamel after enamel and a manufacturing method thereof, wherein the steel comprises the following chemical components in percentage by weight: 0.035 to 0.054 percent of C, less than or equal to 0.10 percent of Si, 0.74 to 0.94 percent of Mn, 0.071 to 0.091 percent of P, 0.012 to 0.029 percent of S, 0.71 to 0.91 percent of Cr, 0.19 to 0.22 percent of Ti, 0.015 to 0.045 percent of Als, 0.0061 to 0.0079 percent of N, 0.053 to 0.073 percent of Sb, 0.0015 to 0.0029 percent of RE, and the balance of Fe and inevitable impurities. The advantages are that: the scale explosion resistance, the adherence performance, the pinhole defect free and the high strength of the enameled steel plate are improved, precious metal elements are not required to be added, and the economy is good.
Description
Technical Field
The invention belongs to the technical field of low-alloy hot rolled steel plate production, and particularly relates to a 350 MPa-grade rare earth hot rolled steel plate for double-sided enamel with excellent enameling performance and a manufacturing method thereof.
Background
Enamel products taking steel plates as metal substrates are closely related to people in daily life, and are widely applied to industries such as household appliances, metallurgy, chemical industry, buildings and the like to manufacture kitchen utensils, barbecue ovens, water heater liners, sanitary wares, building veneers, assembled reaction tanks and the like. With the increasing requirements of the country on environmental protection, the materials of the steel are high-strength hot-rolled steel plates, which are used for equipment of urban large-scale water treatment plants, environmental protection facilities, large storage tanks and the like, and are required to have high strength after high-temperature enameling, to allow double-sided enameling and to have good fish scale resistance.
In the prior art, patent application No.: 201010215739.6, discloses a high strength hot rolled steel sheet for double-sided enameling and a method for manufacturing the same, which adopts a composite micro-alloying design of low carbon and V, ti, and simultaneously adds Cr and Cu, and the addition of Cu is beneficial to surface deposition, thereby improving the adhesion performance between the copper sheet and enamel, but Cu is generally added together with Ni, and the surface of a steel sheet added alone is easy to crack, and has strict requirements on a hot rolling process. The yield strength after the enameling firing is over 280MPa, and the use requirement cannot be completely met. Patent application No.: 201510548170.8 discloses a hot rolled steel plate for high-strength double-sided enamel after enamel and a manufacturing method thereof, wherein a composite micro-alloying design of Nb, V and Ti is adopted, and meanwhile, B elements are selectively added, and Nb and V elements are expensive and high in production cost. Patent application No.: 201710387916.0 discloses a high strength steel for hot rolling double-sided enamel, a double-sided enamel steel and a manufacturing method thereof, which adopt a high C content, are effective for improving the strength after enamel, but have high C content, and are easy to generate air hole defects after enamel. And the composite micro-alloying of Nb, V and Ti is adopted, so that the cost is higher. Patent application No.: 200510047758.1 discloses a hot-rolled double-sided enameled steel plate and a manufacturing method thereof, the steel plate adopts Ti and V composite micro-alloying design, and the strength after enameling can not be ensured to be more than 350MPa, so that the use requirement of users can not be completely met. Patent application No.: 201811453323.0 discloses a hot rolled steel sheet with excellent double-sided enameling performance and high strength performance after enameling and a manufacturing method thereof, and although the yield strength of the steel sheet after enameling can reach more than 350MPa, the steel sheet is easy to generate pinhole defects and increase the risk of scale explosion after enameling by adopting a high content of C.
The above patents are mainly designed to increase the C content or to increase the post-enameling strength of the steel sheet by using composite microalloying compositions of Nb, V and Ti. Therefore, how to obtain a high-strength steel plate with excellent enameling performance by adopting low-cost component design is one of the technical difficulties to be solved urgently in the field.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide the rare earth hot-rolled steel plate for the 350 MPa-grade double-sided enamel and the manufacturing method thereof, which solve the problems of insufficient strength or high production cost of the hot-rolled double-sided enamel steel plate, have good fish scaling resistance, good adherence, no pinhole defect and high strength, and are suitable for manufacturing large assembled reaction tanks.
In order to realize the purpose, the invention is realized by the following technical scheme:
a350 MPa-grade rear earth hot rolled steel plate for double-sided enamel after enamel, which comprises the following chemical components in percentage by weight: 0.035 to 0.054 percent of C, less than or equal to 0.10 percent of Si, 0.74 to 0.94 percent of Mn, 0.071 to 0.091 percent of P, 0.012 to 0.029 percent of S, 0.71 to 0.91 percent of Cr, 0.19 to 0.22 percent of Ti, 0.015 to 0.045 percent of Als, 0.0061 to 0.0079 percent of N, 0.053 to 0.073 percent of Sb, 0.0015 to 0.0029 percent of RE, and the balance of Fe and inevitable impurities.
The thickness of the steel plate is 3-12 mm, the yield strength is more than 550MPa, the tensile strength is more than 650MPa, and the elongation is more than 19%.
The reasons for selecting the above alloy element types and contents are as follows:
c is a key element for obtaining high strength of the steel plate and is the most economical element, but when the content of C is too high, the probability of generating pinhole defects after the enameling firing is higher. The content of C in the invention is limited to 0.035% -0.054%.
Si can be dissolved in ferrite and austenite to improve the hardness and strength of steel, but if the content is too high, red iron scale on the surface of a rolled steel plate is difficult to remove seriously, thereby affecting the adhesion of the steel plate. The content of Si is limited to not more than 0.10% in the present invention.
The main role of Mn in steel is solid solution strengthening, which acts to improve the strength of the steel sheet. The transformation temperature of austenite to ferrite can be obviously reduced, the microstructure of steel is refined, the strength index of a steel plate is ensured, but the plasticity of the steel is seriously reduced due to excessive Mn content, and the content of Mn is controlled to be 0.74-0.94%.
P has good solid solution strengthening effect and has no adverse effect on enamel performance. In the invention, P is used for compensating the insufficient solid solution strengthening caused by the reduction of C, but the content of P is too high, so that the center segregation is easy to occur, the continuous casting billet is layered, and the mechanical property of the steel plate in the thickness direction is adversely affected, so that the content of P is controlled to be 0.071-0.091%.
S is an impurity element in steel, so that the ductility and the welding performance are obviously reduced, and in the steel without titanium, sulfur is usually combined with manganese to form MnS inclusions, but in the invention, because of adding higher content of titanium, sulfur preferentially forms compounds with titanium, a certain hydrogen storage effect can be achieved, and the fish scaling resistance of the steel plate is improved. The content of the steel is controlled to be 0.012-0.029%.
Cr is beneficial to surface deposition, so that the adherence between the Cr and the porcelain glaze is improved, the scaling resistance is improved, and meanwhile, the Cr has a certain solid solution strengthening effect and improves the strength of ferrite. The content range of the invention is limited to 0.71-0.91%.
Sb usually exists in steel as a harmful element, and a proper amount of Sb can be enriched on the surface of the steel in the production process of the steel, so that the H of Fe in the high-temperature enameling process is inhibited 2 The reduction of O reduces the sources of H atoms dissolved in steel, reduces the enrichment of hydrogen between a porcelain layer and a steel interface, and is favorable for avoiding pinhole defects and reducing the risk of scale explosion. The content range of the invention is limited to 0.053% -0.073%.
Ti is a strong carbonitride forming element and is an important microalloy strengthening element in the invention, not only can effectively refine grains, but also can form fine carbide, nitride or carbonitride with C, N, S, not only can strengthen the strength of a matrix, but also can provide a hydrogen trapping trap and inhibit the occurrence of scale explosion after enameling firing. The invention limits its range to 0.19% to 0.22%.
Als is a commonly used deoxidizer, and the range of the deoxidizer is 0.015 to 0.045 percent.
RE can refine impurities in steel, reduce segregation of harmful elements in grain boundaries, interact with low-melting-point impurities such as phosphorus and antimony to form high-melting-point compounds, and inhibit segregation of the impurities on the grain boundaries. The rare earth has hydrogen trapping property, and the fish scaling resistance of the steel is improved. The invention limits the range to 0.0015% -0.0029%.
N is an element existing in the smelting process, and because one of the characteristics of the invention is to adopt Ti microalloying technology, and Ti is an element with strong activity, the Ti reacts with elements such as O, N, S in steel, and the like, if the content of N is too high, tiN with coarse size can be separated out in molten steel, the growth of austenite grains can not be prevented, the precipitation strengthening effect can not be realized, and the grain refining and precipitation strengthening effects of Ti can be reduced. Therefore, the range of N control in the invention is 0.0061% -0.0079%.
A manufacturing method of a rear earth hot rolled steel plate for 350 MPa-grade double-sided enamel after enamel, which comprises the following process routes: pre-desulfurizing molten steel, performing top and bottom combined blowing of a converter, performing LF external refining, continuously casting a plate blank, heating the plate blank, continuously hot rolling, cooling by laminar flow and coiling; the method specifically comprises the following steps:
1) The thickness of the casting blank is 200-230 mm; when the slab is heated, controlling the tapping temperature of the casting blank to be 1253-1283 ℃;
2) The hot continuous rolling adopts two-stage controlled rolling, each pass of rough rolling is descaled, and the outlet temperature of the rough rolling is over 1100 ℃; the initial rolling temperature of finish rolling is 1081-1099 ℃, and the final rolling temperature of finish rolling is 913-938 ℃;
3) After finish rolling, laminar cooling is carried out, the steel is cooled to 621-651 ℃ at the cooling rate of 23-39 ℃/s for coiling, and then air cooling is carried out to the room temperature.
The laminar cooling adopts front section centralized cooling.
The process parameter selection reason in the manufacturing process of the 350MPa grade rare earth hot rolled steel plate for double-sided enamel after enamel is as follows:
(1) Heating the continuous casting blank at 1253-1283 ℃; because the invention adds Ti with higher content, and Ti can combine with C, N to form stable carbide and nitride, the solid solution temperature is higher, in order to ensure that Ti can disperse and precipitate fine TiC in the rolling process and play a role in strong precipitation strengthening, the solid solution amount of titanium carbide and titanium nitride needs to be ensured, and simultaneously, the soaking temperature is determined to be 1253 ℃ -1283 ℃ by combining the two aspects in consideration of the inhibiting effect of the titanium carbide and the titanium nitride on the growth of original austenite grains.
(2) Rough rolling is carried out in the temperature range higher than 1100 ℃, band steel is not allowed to swing, finish rolling is started at 1081-1099 ℃, the start rolling temperature of finish rolling is higher than 1099 ℃, crystal grains of finished products are not easy to refine, and the fine grain strengthening effect is poor; the temperature of the tail part of the strip steel is quickly reduced below 1081 ℃, so that the load of a finish rolling machine frame is increased, and accidents are easily caused;
(3) When the finishing rolling temperature is lower, the grain size of ferrite is favorably refined, and the fine-grain strengthening effect is improved, but simultaneously, the lower finishing rolling temperature can induce the deformation induced precipitation of carbonitride. Although the precipitates inhibit the growth of austenite grains and perform certain functions of fine grain strengthening and precipitation strengthening, the precipitates are relatively large in size compared with ferrite-precipitated nano-scale particles, and the precipitation strengthening effect is reduced. Therefore, the finishing temperature of the invention is preferably controlled to be 913 ℃ to 938 ℃.
(4) And after rolling, carrying out laminar cooling and coiling. The laminar flow adopts anterior segment centralized cooling, adopts anterior segment centralized cooling's purpose: firstly, crystal grains are refined, and the strength is improved; and secondly, the advance precipitation of TiC in the water cooling process is inhibited, so that Ti and C which are dissolved in the matrix are formed in the coiling process as much as possible, and the precipitation strengthening effect is very strong. When the cooling rate is too low, ti carbide precipitates during cooling, coarse particles increase in the final product, the precipitation strengthening effect after coiling is insufficient, and the cooling rate is set to 23 to 39 ℃/s in order to ensure that a large amount of fine precipitated particles of the second phase are obtained after coiling. The coiling temperature is too high, the precipitation obtained after coiling is relatively thick, and the precipitation strengthening effect is weak; when the coiling temperature is too low, precipitation of precipitates becomes insufficient, and a desired strength cannot be obtained. Therefore, the coiling temperature in the present invention is preferably controlled to 621 to 651 ℃.
The yield strength, the tensile strength and the elongation of the double-sided enameled steel plate produced by adopting the steel plate are respectively greater than 350MPa, 440MPa and 29 percent; and the results of the fish scale explosion resistance performance test are that the fish scale explosion is not generated, the adherence performance is excellent and reaches grade 1, and no pinhole defect exists.
In the firing process of the double-sided enameled pressed steel: enameling and burning the base glaze at 870-880 ℃ for 9-18min; the enamel firing temperature is 780-800 ℃, and the enamel firing time is 7.5-15min.
Compared with the prior art, the invention has the beneficial effects that:
the 350MPa grade double-sided enamel rare earth hot rolled steel plate after enameling is designed by adopting alloy components of high Ti, mn, cr and P solid solution strengthening elements and alloy elements Sb and RE, and forms a certain amount of TiN, ti (CN) and Ti (RE) through the synergistic action of the Mn, cr and P elements 4 S 2 C 2 TiC, thereby improving the adherence and scale resistance of the steel plate after the enamelingExplosiveness and strength, and the yield strength after enameling can reach more than 350 MPa. The invention does not need to add noble metal elements such as Nb, V, mo and the like, and has good economical efficiency.
Detailed Description
The present invention is described in detail below, but it should be noted that the practice of the invention is not limited to the following embodiments.
A350 MPa-grade rear earth hot rolled steel plate for double-sided enamel after enamel, which comprises the following chemical components in percentage by weight: 0.035 to 0.054 percent of C, less than or equal to 0.10 percent of Si, 0.74 to 0.94 percent of Mn, 0.071 to 0.091 percent of P, 0.012 to 0.029 percent of S, 0.71 to 0.91 percent of Cr, 0.19 to 0.22 percent of Ti, 0.015 to 0.045 percent of Als, 0.0061 to 0.0079 percent of N, 0.053 to 0.073 percent of Sb, 0.0015 to 0.0029 percent of RE, and the balance of Fe and inevitable impurities.
A manufacturing method of a rear earth hot rolled steel plate for 350 MPa-grade double-sided enamel after enamel, which comprises the following process routes: pre-desulfurizing molten steel, performing top and bottom combined blowing of a converter, performing LF external refining, continuously casting a plate blank, heating the plate blank, continuously hot rolling, cooling by laminar flow and coiling; the method specifically comprises the following steps:
1) The thickness of the casting blank is 200-230 mm; when the slab is heated, controlling the tapping temperature of the casting blank to be 1253-1283 ℃;
2) The hot continuous rolling adopts two-stage controlled rolling, the rough rolling adopts a 3+3 mode, the descaling is carried out on each pass of the rough rolling, and the outlet temperature of the rough rolling is more than 1100 ℃; the finish rolling adopts 7 stands for continuous rolling, the start rolling temperature of the finish rolling is 1081-1099 ℃, and the finish rolling temperature of the finish rolling is 913-938 ℃;
3) After finish rolling, laminar cooling is carried out, the steel is cooled to 621-651 ℃ at the cooling rate of 23-39 ℃/s for coiling, and then air cooling is carried out to the room temperature. And front-section centralized cooling is adopted in laminar cooling.
The chemical components of a 350MPa grade rare earth hot rolled steel plate for double-sided enamel after enamel are shown in Table 1.
Table 1 shows the chemical compositions in wt% of examples 1 to 10
| Serial number | C | Si | Mn | P | S | Als | Cr | Ti | Sb | RE | N |
| 1 | 0.035 | 0.08 | 0.94 | 0.091 | 0.012 | 0.045 | 0.91 | 0.22 | 0.073 | 0.0029 | 0.0061 |
| 2 | 0.036 | 0.05 | 0.92 | 0.089 | 0.016 | 0.043 | 0.89 | 0.22 | 0.069 | 0.0026 | 0.0062 |
| 3 | 0.038 | 0.02 | 0.90 | 0.087 | 0.013 | 0.039 | 0.87 | 0.22 | 0.067 | 0.0025 | 0.0064 |
| 4 | 0.038 | 0.04 | 0.88 | 0.085 | 0.018 | 0.034 | 0.85 | 0.21 | 0.065 | 0.0023 | 0.0066 |
| 5 | 0.041 | 0.02 | 0.86 | 0.083 | 0.019 | 0.031 | 0.83 | 0.21 | 0.063 | 0.0022 | 0.0069 |
| 6 | 0.046 | 0.07 | 0.83 | 0.081 | 0.021 | 0.027 | 0.81 | 0.20 | 0.061 | 0.0023 | 0.0071 |
| 7 | 0.049 | 0.03 | 0.81 | 0.078 | 0.023 | 0.024 | 0.78 | 0.20 | 0.059 | 0.0021 | 0.0073 |
| 8 | 0.052 | 0.06 | 0.78 | 0.075 | 0.024 | 0.021 | 0.75 | 0.19 | 0.057 | 0.0018 | 0.0075 |
| 9 | 0.053 | 0.06 | 0.76 | 0.073 | 0.026 | 0.017 | 0.73 | 0.19 | 0.055 | 0.0016 | 0.0078 |
| 10 | 0.054 | 0.04 | 0.74 | 0.071 | 0.029 | 0.015 | 0.71 | 0.19 | 0.053 | 0.0015 | 0.0079 |
The rare earth hot rolled steel sheets of examples 1 to 10 having the chemical compositions of Table 1 were manufactured by the following processes:
smelting in a converter, then carrying out external refining, and casting to obtain a continuous casting billet. The thickness of the continuous casting billet is 200mm-230mm, the continuous casting billet is sent to a hot rolling production line, the heating outlet temperature of the casting billet is 1253-1283 ℃, the starting temperature of finish rolling is 1082-1099 ℃, the finishing temperature of finish rolling is 913-938 ℃, laminar cooling is adopted after rolling, the cooling speed is 23-39 ℃/s, the coiling temperature is 621-651 ℃, and air cooling is carried out to the room temperature after coiling.
The rolling process parameters of the steels of the examples are shown in table 2.
TABLE 2 Rolling Process parameters for examples 1-10
The parameters of the enameling firing process for the steels of the respective examples are shown in table 3.
TABLE 3 enameling firing Process parameters for examples 1-10
| Serial number | Thickness, mm | Enameling temperature of the base glaze, DEG C | Incubation time, min | Enameling temperature of cover glaze, DEG C | Incubation time, min |
| Example 1 | 12 | 870 | 18 | 800 | 15 |
| Example 2 | 11 | 870 | 17 | 800 | 14 |
| Example 3 | 10 | 870 | 15 | 800 | 12.5 |
| Example 4 | 9 | 870 | 14 | 800 | 11.5 |
| Example 5 | 8 | 870 | 13 | 800 | 10.5 |
| Example 6 | 7 | 870 | 11 | 800 | 9 |
| Example 7 | 6 | 880 | 10 | 800 | 8 |
| Example 8 | 5 | 880 | 9 | 780 | 8 |
| Example 9 | 4 | 880 | 9 | 780 | 8 |
| Example 10 | 3 | 880 | 9 | 780 | 7.5 |
The mechanical properties of the steels of the examples are shown in Table 4.
TABLE 4 mechanical Properties of examples 1 to 10
The enameling firing temperature of the ground glaze is 870-880 ℃, the enameling firing temperature of the cover glaze is 780-800 ℃, and the enameling firing time of the ground glaze and the cover glaze is correspondingly adjusted according to the different thicknesses of the steel plates. As can be seen from Table 4, the steels of examples 1-10 all had pre-enameling yield strengths of greater than 550MPa, tensile strengths of greater than 650MPa, and elongations of greater than 19%; the yield strength of the enamel is more than 350MPa, the tensile strength is more than 440MPa, and the elongation is more than 29%. And the results of the fish scale explosion resistance performance test are that the fish scale explosion is not generated, the adherence performance is excellent and reaches grade 1, and no pinhole defect exists.
Claims (6)
1. The 350 MPa-grade rare earth hot-rolled steel plate for double-sided enamel after enamel is characterized by comprising the following chemical components in percentage by weight:
0.035 to 0.054 percent of C, less than or equal to 0.10 percent of Si, 0.74 to 0.94 percent of Mn, 0.071 to 0.091 percent of P, 0.012 to 0.029 percent of S, 0.71 to 0.91 percent of Cr, 0.19 to 0.22 percent of Ti, 0.015 to 0.045 percent of Als, 0.0061 to 0.0079 percent of N, 0.053 to 0.073 percent of Sb, 0.0015 to 0.0029 percent of RE, and the balance of Fe and inevitable impurities.
2. The rare earth hot-rolled steel sheet for double-sided enameling at the post-enameling 350MPa level according to claim 1, wherein the steel sheet has a thickness of 3 to 12mm, a yield strength of more than 550MPa, a tensile strength of more than 650MPa, and an elongation of more than 19%.
3. The rare earth hot-rolled steel sheet for double-sided enameling at the post-enameling 350MPa level according to claim 1 or 2, wherein the double-sided enameled steel sheet produced by using the steel sheet has yield strength of more than 350MPa, tensile strength of more than 440MPa and elongation of more than 29%; and the results of the fish scale explosion resistance performance test are that the fish scale explosion is not generated, the adherence performance is excellent and reaches grade 1, and no pinhole defect exists.
4. The rare earth hot-rolled steel sheet for double-sided enamel at 350MPa after enameling according to claim 3, wherein in the firing process of the double-sided enameled steel sheet: enameling and burning the base glaze at 870-880 ℃ for 9-18min; the enamel firing temperature is 780-800 ℃, and the enamel firing time is 7.5-15min.
5. The manufacturing method of the rare earth hot rolled steel plate for double-sided enameling at post-enameling 350MPa level according to claim 1 or 2, characterized by comprising the following process steps: pre-desulfurizing molten steel, performing top and bottom combined blowing of a converter, performing LF external refining, continuously casting a plate blank, heating the plate blank, continuously hot rolling, cooling by laminar flow and coiling; the method specifically comprises the following steps:
1) The thickness of the casting blank is 200-230 mm; when the slab is heated, controlling the tapping temperature of the casting blank to be 1253-1283 ℃;
2) The hot continuous rolling adopts two-stage controlled rolling, each pass of rough rolling is descaled, and the outlet temperature of the rough rolling is more than 1100 ℃; the initial rolling temperature of finish rolling is 1081-1099 ℃, and the final rolling temperature of finish rolling is 913-938 ℃;
3) After finish rolling, laminar cooling is carried out, the steel is cooled to 621-651 ℃ at the cooling rate of 23-39 ℃/s, coiled and then cooled to room temperature by air.
6. The method for manufacturing a rare earth hot rolled steel sheet for double-sided enameling at post-enameling 350MPa according to claim 5, wherein the laminar cooling employs front-stage concentrated cooling.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5651553A (en) * | 1979-10-01 | 1981-05-09 | Nippon Steel Corp | High strength hot rolled steel sheet for both-side enameling |
| JP2006161139A (en) * | 2004-12-10 | 2006-06-22 | Jfe Steel Kk | Hot rolled steel sheet suitable to warm forming and its production method |
| CN1966753A (en) * | 2005-11-16 | 2007-05-23 | 鞍钢股份有限公司 | Steel plate for hot-rolled double-side enamel and method for producing same |
| CN104419874A (en) * | 2013-09-05 | 2015-03-18 | 鞍钢股份有限公司 | Hot rolled double-faced enamel steel with excellent fish scaling resistance and manufacture method of hot rolled double-faced enamel steel |
| CN104789899A (en) * | 2015-03-02 | 2015-07-22 | 李宏亮 | Steel hot-rolling plate for double-sided enamels, and preparation process thereof |
| CN106480368A (en) * | 2015-08-31 | 2017-03-08 | 鞍钢股份有限公司 | One kind wards off rear high-strength hot rolled steel plate for counter enameling and its manufacture method |
-
2022
- 2022-07-01 CN CN202210767568.0A patent/CN115198183A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5651553A (en) * | 1979-10-01 | 1981-05-09 | Nippon Steel Corp | High strength hot rolled steel sheet for both-side enameling |
| JP2006161139A (en) * | 2004-12-10 | 2006-06-22 | Jfe Steel Kk | Hot rolled steel sheet suitable to warm forming and its production method |
| CN1966753A (en) * | 2005-11-16 | 2007-05-23 | 鞍钢股份有限公司 | Steel plate for hot-rolled double-side enamel and method for producing same |
| CN104419874A (en) * | 2013-09-05 | 2015-03-18 | 鞍钢股份有限公司 | Hot rolled double-faced enamel steel with excellent fish scaling resistance and manufacture method of hot rolled double-faced enamel steel |
| CN104789899A (en) * | 2015-03-02 | 2015-07-22 | 李宏亮 | Steel hot-rolling plate for double-sided enamels, and preparation process thereof |
| CN106480368A (en) * | 2015-08-31 | 2017-03-08 | 鞍钢股份有限公司 | One kind wards off rear high-strength hot rolled steel plate for counter enameling and its manufacture method |
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