Aluminum-containing HRB600E reinforcing steel bar and preparation method thereof

Abstract

The invention discloses an aluminum-containing HRB600E reinforcing steel bar and a preparation method thereof. The aluminum-containing HRB600E reinforcing steel bar comprises the following chemical components in percentage by mass: 0.25 to 0.28 weight percent of C, 1.1 to 1.5 weight percent of Mn, 0.3 to 0.7 weight percent of Si, 0.16 to 0.20 weight percent of V, N, Al and the balance of Fe and inevitable impurities. The sum of the mass percentages of the N and the Al is that the sum of the mass percentages of the N and the Al is 0.3-0.65 Wt%; the mass percentage ratio of N to Al is 1: (4-25). According to the aluminum-containing HRB600E reinforcing steel bar, by controlling the proportion and dosage of N and Al, not only can the welding performance of the aluminum-containing HRB600E reinforcing steel bar be improved, but also the aluminum-containing HRB600E reinforcing steel bar can have high yield strength and high tensile strength.

Description

Technical Field

[0001] The present invention relates to the technical field of metal materials, and more specifically, to an aluminum-containing HRB600E steel bar and a preparation method thereof. Background Art

[0002] In recent years, due to the rapid development of urbanization, high-speed railways, bridges, and the construction industry, higher requirements have been put forward for the performance of steel bars used in construction. In engineering construction, steel bars are an extremely important material that plays a role in strengthening and supporting. Under the background of the era of energy conservation and emission reduction, the situation of ordinary-strength steel bars being the main construction steel cannot meet the current construction needs. Therefore, promoting the use of high-strength steel bars is the mainstream of economic conservation and green manufacturing.

[0003] HRB600E steel bars are mainly used in bridges and high-rise buildings. This type of steel bar is favored by the industry for its high strength and excellent seismic performance. Compared with HRB400E steel bars and HRB500E steel bars, HRB600E steel bars have the characteristics of high strength, good toughness, strong seismic resistance, and economy. For example, the yield point of HRB600E is above 600 MPa, and the tensile strength is above 730 MPa, which is 15 Wt% higher than that of HRB500E hot-rolled ribbed steel bars and 43.75 Wt% higher than that of HRB400E hot-rolled ribbed steel bars; due to high strength, using HRB600E seismic hot-rolled ribbed steel bars can save 12 Wt% of steel compared with HRB500E seismic hot-rolled ribbed steel bars and reduce the self-weight of the building by 50 Wt%, so the construction cost of building projects can be reduced. The performance of HRB600E steel bars is stable with small fluctuations, which is beneficial to improving the stability performance of the overall reinforced concrete structure and enhancing the ability to bear external forces. Its seismic performance is significantly better than that of ordinary non-seismic hot-rolled ribbed steel bars. However, at present, most HRB600E steel bars have poor welding performance due to a relatively high carbon equivalent (mass fraction ≥ 0.25 Wt%), that is, HRB600E steel bars with high carbon content are prone to cracks at the welded joints when bent after welding and are also prone to fracture. Steel bar welding is inevitable in construction. Therefore, HRB600E steel bars with poor welding performance will bend and break in the face of accidents such as earthquakes and building collapses, and will also spread due to the looseness of concrete, resulting in heavy losses.

[0004] Therefore, it is of great significance to develop an aluminum-containing HRB600E steel bar with strong welding performance, high yield strength, and high tensile strength. Summary of the Invention

[0005] The purpose of the present invention is to solve the deficiencies in the prior art and provide an aluminum-containing HRB600E steel bar and a preparation method thereof.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] In a first aspect, the present invention provides an aluminum-containing HRB600E steel bar, and its chemical composition by mass percentage is: C 0.25 - 0.28 Wt%, Mn 1.1 - 1.5 Wt%, Si 0.3 - 0.7 Wt%, V 0.16 - 0.20 Wt%, N, Al, and the balance is Fe and inevitable impurities;

[0008] The sum of the mass percentages of N and Al is: N + Al = 0.3 - 0.65 Wt%; the ratio of the mass percentages of N and Al is 1:(4 - 25).

[0009] For the aluminum-containing HRB600E steel bar of the present invention, by controlling the ratio and dosage of N and Al, on the one hand, during the cooling process after welding of the steel bar, an appropriate amount of fine AlN particles are precipitated, and AlN is used as a nucleation point to promote the formation of ferrite, thereby improving the welding performance of the aluminum-containing HRB600E steel bar; on the other hand, an appropriate amount of Al is used as a ferrite phase region stabilizing element, which can reduce the stability of austenite, reduce the supercooling degree during martensite transformation, and inhibit the formation of martensite during the welding of the steel bar, thereby improving the welding performance of the aluminum-containing HRB600E steel bar. In addition, the aluminum-containing HRB600E steel bar of the present invention also has high yield strength and high tensile strength.

[0010] Preferably, the ratio of the mass percentages of N and Al is one of 1:4, 1:4.5, 1:4.7, 1:5, 1:5.5, 1:6, 1:6.5, 1:7, 1:7.5, 1:8, 1:8.5, 1:9, 1:10, 1:11, 1:12, 1:13, 1:14, 1:15, 1:16, 1:17, 1:18, 1:19, 1:20, 1:21, 1:22, 1:23, 1:24, 1:25 or a range value between any two of them.

[0011] More preferably, the ratio of the mass percentages of N and Al is 1:(4.5 - 23).

[0012] Even more preferably, the ratio of the mass percentages of N and Al is 1:(9 - 19).

[0013] Preferably, the mass percentage of N is 0.015 - 0.070 Wt%, and specifically it can be 0.016 - 0.070 Wt%.

[0014] More preferably, the mass percentage of N is 0.02 - 0.04 Wt%.

[0015] Preferably, the sum of the mass percentages of N and Al is one of 0.3Wt%, 0.35Wt%, 0.4Wt%, 0.45Wt%, 0.5Wt%, 0.55Wt%, 0.6Wt%, 0.65Wt% or a range value between any two of them.

[0016] Preferably, the diameter of the aluminum-containing HRB600E steel bar is 10 - 35 mm, and specifically it can be 25 mm.

[0017] Preferably, the shape of the aluminum-containing HRB600E steel bar is round rod-shaped.

[0018] In a second aspect, the present invention provides a preparation method of an aluminum-containing HRB600E steel bar, including the following steps:

[0019] S1. Blast furnace hot metal smelting

[0020] Weigh the raw materials according to the mass percentages of the chemical components of the aluminum-containing HRB600E steel bar, place them in the blast furnace for smelting to obtain hot metal;

[0021] S2. Desulfurization pretreatment

[0022] Add a desulfurizing agent to the hot metal, and control the mass percentage of S in the hot metal ≤ 0.035Wt%;

[0023] S3. Converter smelting

[0024] Transfer the hot metal treated in step S2 into the converter for phosphorus removal smelting, control the mass percentage of P in the hot metal ≤ 0.020Wt% and the mass percentage of C ≤ 0.06Wt%, and then tap the steel to obtain molten steel;

[0025] S4. LF refining

[0026] Transfer the molten steel into the LF furnace for LF refining, make fine adjustments according to the mass percentages of the chemical components of the aluminum-containing HRB600E steel bar, and make fine adjustments to the temperature of the molten steel. The LF refining process adopts a full-bottom argon stirring mode, control the residence time of the LF furnace in the station ≥ 40 min, and feed SiCaBa wire ≥ 150 m when the LF furnace leaves the station, and soft blow argon ≥ 5 min;

[0027] S5. Continuous casting

[0028] Conduct continuous casting of the molten steel treated in step S4 to obtain a steel billet; wherein: argon is used to protect the molten steel during the continuous casting process, control the casting temperature to be 1510 - 1550 °C, and the drawing speed during the continuous casting process is 1.85 ± 0.05 m / min;

[0029] S6. Rolling

[0030] Roll the billet to obtain aluminum-containing HRB600E steel bars; wherein: control the heating temperature of the billet at 1160 - 1200 °C, the heating time at 70 - 90 min, the rolling speed at 12.2 - 15.5 m / s, the starting rolling temperature at 1020 - 1090 °C, and do not use water cooling.

[0031] Preferably, in step S1, the smelting temperature is 1600 - 1700 °C.

[0032] Preferably, in step S2, the desulfurizing agent is at least one of calcium carbide, lime, and calcium silicate.

[0033] Preferably, in step S3, the double slag method is used for smelting and dephosphorization.

[0034] Preferably, in step S3, argon bottom blowing stirring is required during the tapping process; in the present invention, the purpose of argon bottom blowing stirring is to make the molten steel composition and temperature uniform and promote the floating of inclusions in the molten steel.

[0035] Preferably, in step S3, the tapping temperature is 1600 - 1680 °C.

[0036] Preferably, in step S4, the fine-tuning of the molten steel temperature means fine-tuning the molten steel temperature within the range of 1575 - 1590 °C.

[0037] Preferably, in step S4, the SiCaBa wire, calculated by mass percentage, includes:

[0038] Si 0.5 - 1.5 Wt%, Ca 0.5 - 1.5 Wt%, Ba 0.005 - 0.02 Wt%, and the balance is Fe and unavoidable impurities.

[0039] Preferably, in step S5, the continuous casting process uses argon to protect the pouring of molten steel, which means using a protective sleeve to protect the pouring from the ladle to the tundish, covering the tundish molten steel surface with a tundish covering agent, the tundish pouring temperature is 1510 - 1550 °C, using a submerged entry nozzle to protect the pouring from the tundish to the mold, and adding a low-alloy steel mold powder to the mold molten steel surface, so as to keep the molten steel warm and prevent secondary oxidation of the molten steel.

[0040] More preferably, the tundish covering agent is at least one of quartz and magnesite.

[0041] More preferably, the low-alloy steel mold powder is at least one of calcium oxide, magnesium oxide, and barium oxide.

[0042] Preferably, in step S6, the rolling is carried out using an 18-stand fully automatic continuous bar rolling mill, which includes a 6-pass roughing mill, an 8-pass intermediate rolling mill, and a 4-pass finishing mill.

[0043] In the rolling process of step S6 of the present invention, if the starting rolling temperature is too high or too low, it will be disadvantageous to the controlled rolling temperature and the rolling reduction control rolling.

[0044] Preferably, after the rolling in step S6, at least one of shearing, cooling, and sizing is further included.

[0045] More preferably, the cooling is performed by natural air cooling on a cooling bed to room temperature.

[0046] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0047] For the aluminum-containing HRB600E steel bars of the present invention, by controlling the ratio and dosage of N and Al, on the one hand, during the cooling process after welding of the steel bars, an appropriate amount of fine AlN particles are precipitated, and AlN is used as the nucleation point to promote the formation of ferrite, thereby improving the welding performance of the aluminum-containing HRB600E steel bars; on the other hand, an appropriate amount of Al is used as a ferrite phase region stabilizing element, which can reduce the stability of austenite and the supercooling degree during the martensite transformation, so that the formation of martensite can be inhibited during the welding of the steel bars, thereby improving the welding performance of the aluminum-containing HRB600E steel bars. In addition, the aluminum-containing HRB600E steel bars of the present invention also have high yield strength and high tensile strength. Description of the Drawings

[0048] Figure 1 It is the metallographic structure diagram of the aluminum-containing HRB600E steel bars in Example 1.

[0049] Figure 2 It is the physical diagram of the aluminum-containing HRB600E steel bars in Example 1 after the welding performance test.

[0050] Figure 3 It is the physical diagram of the aluminum-containing HRB600E steel bars in Comparative Example 4 after the welding performance test. Detailed Embodiments

[0051] To better illustrate the purpose, technical solution and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0052] For the experimental methods without specific conditions in the following examples, they are usually carried out according to the conventional conditions in the art or according to the conditions recommended by the manufacturers; the raw materials, reagents, etc. used, unless otherwise specified, are all raw materials and reagents that can be obtained from commercial channels such as conventional markets.

[0053] Example 1

[0054] This embodiment provides an aluminum-containing HRB600E steel bar, and its chemical composition by mass percentage is: C 0.26Wt%, Mn 1.48Wt%, Si 0.6Wt%, V 0.17Wt%, N, Al, and the balance is Fe and unavoidable impurities;

[0055] The sum of the mass percentages of N and Al is: N + Al = 0.4Wt%; the ratio of the mass percentages of N and Al is 1:19; the mass percentage of N is 0.020Wt%; the mass percentage of Al is 0.38Wt%; the diameter of the aluminum-containing HRB600E steel bar is 25mm and the shape is round bar-shaped;

[0056] The preparation method of the above aluminum-containing HRB600E steel bar includes the following steps:

[0057] S1. Blast furnace hot metal smelting

[0058] Weigh the raw materials according to the mass percentage of the chemical composition of the aluminum-containing HRB600E steel bar, place them in the blast furnace for smelting to obtain hot metal; the temperature of the smelting is 1687°C.

[0059] S2. Desulfurization pretreatment

[0060] Add a desulfurizing agent to the hot metal to control the mass percentage of S in the hot metal to 0.02Wt%; the desulfurizing agent is calcium silicate;

[0061] S3. Converter smelting

[0062] Transfer the hot metal treated in step S2 into the converter and use the double slag method for phosphorus removal smelting, control the mass percentage of P in the hot metal to 0.015Wt% and the mass percentage of C to 0.05Wt%, then tap the steel to obtain molten steel; argon gas stirring from the bottom is required during the tapping process; in the present invention, the purpose of argon gas stirring from the bottom is to make the composition and temperature of the molten steel uniform and promote the floating of inclusions in the molten steel; the tapping temperature is 1610°C;

[0063] S4. LF refining

[0064] Transfer the molten steel into the LF furnace for LF refining, make fine adjustments according to the mass percentage of the chemical composition of the aluminum-containing HRB600E steel bar, and make fine adjustments to the temperature of the molten steel (make the temperature of the molten steel 1585°C). The LF refining process adopts the whole-process argon gas stirring mode from the bottom, control the residence time of the LF furnace in the station to be 45min, and feed 150m of SiCaBa wire when the LF furnace leaves the station, and soft blow argon for 5min;

[0065] The SiCaBa wire, calculated by mass percentage, includes: Si 1.0Wt%, Ca 1.0Wt%, Ba 0.01Wt%, and the balance is Fe and unavoidable impurities;

[0066] S5. Continuous casting

[0067] The molten steel processed in step S4 is subjected to continuous casting of continuous casting billets to obtain steel billets; wherein: argon is used for protecting the pouring of molten steel during the continuous casting process, the pouring temperature is controlled at 1525 °C, and the drawing speed during the continuous casting process is 1.85 m / min;

[0068] The use of argon for protecting the pouring of molten steel during the continuous casting process means that a protective sleeve is used for protecting the pouring from the ladle to the tundish, the molten steel level in the tundish is covered with tundish covering agent (quartz), the pouring temperature in the tundish is 1525 °C, and a submerged entry nozzle is used for protecting the pouring from the tundish to the mold, and a low-alloy steel mold powder (calcium oxide) is added to the molten steel level in the mold, so as to keep the molten steel warm and prevent secondary oxidation of the molten steel;

[0069] S6. Rolling

[0070] The steel billets are rolled to obtain aluminum-containing HRB600E steel bars; wherein: the heating temperature of the steel billets is controlled at 1180 °C, the heating time is 90 min, the rolling speed is controlled at 13.5 m / s, the starting rolling temperature is 1040 °C, and water cooling is not used;

[0071] The rolling is carried out using an 18-stand fully automatic continuous bar rolling mill, which includes a 6-pass roughing mill, an 8-pass intermediate rolling mill, and a 4-pass finishing mill;

[0072] After the rolling in step S6, it also includes shearing, cooling, and sizing; the cooling is carried out by natural air cooling on a cooling bed to room temperature.

[0073] Examples 2-4 and Comparative Examples 1-3

[0074] Examples 2-4 and Comparative Examples 1-3 provide different aluminum-containing HRB600E steel bars, the difference from Example 1 is that the mass percentage ratio of N and Al is different, and the rest are the same as in Example 1, as shown in the following table:

[0075] Table 1 Mass percentage ratio of N and Al in Examples 1-4 and Comparative Examples 1-3

[0076]

[0077]

[0078] Examples 5-6 and Comparative Examples 4-5

[0079] Examples 5-6 and Comparative Examples 4-5 provide different aluminum-containing HRB600E steel bars, the difference from Example 1 is that the sum of the mass percentages of N and Al is different, and the rest are the same as in Example 1, as shown in the following table:

[0080] Table 2 Mass percentage sum of N and Al in Example 1, Examples 5 - 6 and Comparative Examples 4 - 5

[0081] Sum of mass percentages of N and Al (N + Al) / Wt% Example 1 0.4 Example 5 0.3 Example 6 0.65 Comparative Example 4 0.8 Comparative Example 5 0.1

[0082] Example 7

[0083] This example provides an aluminum - containing HRB600E steel bar, and its chemical composition by mass percentage is: C 0.27 Wt%, Mn 1.45 Wt%, Si 0.58 Wt%, V 0.16 Wt%, N, Al, and the balance is Fe and inevitable impurities;

[0084] The sum of the mass percentages of N and Al is: N + Al = 0.418 Wt%; the ratio of the mass percentages of N and Al is 1:14; the mass percentage of N is 0.028 Wt%; the mass percentage of Al is 0.39 Wt%; the diameter of the aluminum - containing HRB600E steel bar is 25 mm and the shape is round bar - shaped;

[0085] The preparation method of the above - mentioned aluminum - containing HRB600E steel bar is the same as that of Example 1.

[0086] Comparative Example 6

[0087] This comparative example provides an aluminum - containing HRB600E steel bar, and its chemical composition by mass percentage is: C 0.26 Wt%, Mn 1.46 Wt%, Si 0.62 Wt%, V 0.17 Wt%, N 0.022 Wt%, and the balance is Fe and inevitable impurities;

[0088] The diameter of the aluminum - containing HRB600E steel bar is 25 mm and the shape is round bar - shaped;

[0089] The preparation method of the above - mentioned aluminum - containing HRB600E steel bar is the same as that of Example 1.

[0090] Performance test

[0091] The performance tests on the aluminum - containing HRB600E steel bars of each example and comparative example are as follows:

[0092] 1. According to Appendix D (Table D.1) of the GB / T 228.1 - 2010 standard, the aluminum - containing HRB600E steel bars of each example or comparative example are respectively processed into round - bar - shaped standard tensile specimens, and then the yield strength (R eL ), tensile strength (R m ), elongation after fracture (A), and maximum elongation (A gt ) of the aluminum - containing HRB600E steel bars are respectively tested by a universal tensile testing machine, where:

[0093] The yield strength (R eL ) ≥ 600 MPa is the qualified standard for the yield strength, the tensile strength (R m ) ≥ 730 MPa is the qualified standard for the tensile strength, the elongation after fracture (A) ≥ 15% is the qualified standard for the elongation after fracture, and the maximum elongation (A gt ) ≥ 10% is the qualified standard for the maximum elongation (A gt );

[0094] In addition, the strength ratio (R m / R eL ) of the aluminum-containing HRB600E steel bar is calculated by the formula R m / R eL ), and the strength ratio (R m / R eL ) ≥ 1.25 is the qualified standard;

[0095] 2. Welding performance test

[0096] The small-sized steel bar (round bar, 80 mm long, 6 mm in diameter) is welded in the middle of the aluminum-containing HRB600E steel bar (410 mm long, 25 mm in diameter) of each example or comparative example by resistance spot welding, and then the aluminum-containing HRB600E steel bar is subjected to a 90° bending test. Observe the cracks and fractures at the welded joints of the aluminum-containing HRB600E steel bar and conduct grading as follows:

[0097] Grade 0 - There are neither cracks nor fractures at the welded joints of the aluminum-containing HRB600E steel bar, as Figure 2 shown;

[0098] Grade 1 - There are a small number of cracks at the welded joints of the aluminum-containing HRB600E steel bar, but there is no fracture;

[0099] Grade 2 - There are more cracks at the welded joints of the aluminum-containing HRB600E steel bar, but there is no fracture;

[0100] Grade 3 - Fracture occurs at the welded joints of the aluminum-containing HRB600E steel bar, as Figure 3 shown;

[0101] The larger the grade number, the worse the welding performance of the aluminum-containing HRB600E steel bar;

[0102] The experimental results are as follows:

[0103] Table 3 Performance test results of aluminum-containing HRB600E steel bars in each example and comparative example

[0104]

[0105]

[0106] Figure 1 Microstructure diagram of the aluminum-containing HRB600E steel bar in Example 1. Figure 2 Physical diagram of the aluminum-containing HRB600E steel bar in Example 1 after welding performance test. Figure 3 Physical diagram of the aluminum-containing HRB600E steel bar in Comparative Example 4 after welding performance test.

[0107] From Table 3 and Figures 1 - 3 It can be seen that the aluminum-containing HRB600E steel bar of the present invention has strong welding performance, high yield strength, and high tensile strength. In particular, its yield strength ≥ 605 MPa, tensile strength ≥ 770 MPa, strength ratio of yield to tensile ≥ 1.25, elongation after fracture ≥ 15.0%, and maximum elongation ≥ 10.0%, meeting the requirements of seismic steel bars and improving the safety performance of the product.

[0108] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. An aluminum-containing HRB600E steel bar, characterized in that: Its chemical composition is calculated by mass percentage: C 0.25-0.28Wt%, Mn 1.1-1.5Wt%, Si 0.3-0.7Wt%, V 0.16-0.20Wt%, N, Al, and the balance is Fe and unavoidable impurities; The sum of the mass percentages of N and Al is: N+Al=0.3-0.65Wt%; the mass percentage ratio of N and Al is 1:(4-25).

2. The aluminum-containing HRB600E steel bar according to claim 1, characterized in that: The mass percentage ratio of N to Al is 1:(4.5-23).

3. The aluminum-containing HRB600E steel bar according to claim 1, characterized in that: The mass percentage ratio of N to Al is 1:(9-19).

4. The aluminum-containing HRB600E steel bar according to claim 1, characterized in that: The mass percentage of N is 0.015-0.070Wt%.

5. The method for preparing the aluminum-containing HRB600E steel bar according to any one of claims 1 to 4, characterized in that: The steps include: S1. Blast furnace molten iron smelting Weighing the raw materials according to the mass percentage of the chemical composition of the aluminum-containing HRB600E steel bar, placing them in a blast furnace for smelting to obtain molten iron; S2. Desulfurization pretreatment Add desulfurizer into the molten iron to control the mass percentage of S in the molten iron to ≤0.035Wt%; S3. Converter smelting The molten iron treated in step S2 is transferred into a converter for smelting and dephosphorization, the mass percentage of P in the molten iron is controlled to be ≤0.020Wt%, and the mass percentage of C in the molten iron is controlled to be ≤0.06Wt%, and then steel is tapped to obtain molten steel; S4.LF Refining The molten steel is transferred to the LF furnace for LF refining, and the chemical composition mass percentage of the aluminum-containing HRB600E steel bar is finely adjusted, and the temperature of the molten steel is finely adjusted. The LF refining process adopts the full bottom blowing argon stirring mode, and the LF furnace is controlled to be in the station for ≥40min, and the SiCaBa line is fed ≥150m when the LF furnace leaves the station, and the soft blowing argon is ≥5min; S5.Continuous casting The molten steel treated in step S4 is continuously cast to obtain a steel billet; wherein: argon is used to protect the molten steel pouring during the continuous casting process, the pouring temperature is controlled to be 1510-1550° C., and the casting speed during the continuous casting process is 1.85±0.05 m / min; S6. Rolling The steel billet is rolled to obtain aluminum-containing HRB600E steel bars; wherein: the heating temperature of the steel billet is controlled to be 1160-1200°C, the heating time is 70-90min, the rolling speed is controlled to be 12.2-15.5m / s, the starting rolling temperature is 1020-1090°C, and no water penetration is achieved.

6. The method for preparing the aluminum-containing HRB600E steel bar according to claim 5, characterized in that: In step S1, the smelting temperature is 1600-1700°C.

7. The method for preparing the aluminum-containing HRB600E steel bar according to claim 5, characterized in that: In step S2, the desulfurizing agent is at least one of calcium carbide, lime and calcium silicate.

8. The method for preparing the aluminum-containing HRB600E steel bar according to claim 5, characterized in that: In step S3, the smelting and dephosphorization adopts a double slag method.

9. The method for preparing the aluminum-containing HRB600E steel bar according to claim 5, characterized in that: In step S3, the temperature of the steel tapping is 1600-1680°C.

10. The method for preparing the aluminum-containing HRB600E steel bar according to claim 5, characterized in that: The said fine adjustment of the temperature of the molten steel refers to fine adjustment of the temperature of the molten steel within the range of 1575-1590°C.

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