Production method of high-nitrogen anti-seismic reinforcing steel bar structure and reinforcing steel bar structure

Abstract

The invention discloses a production method for controlling the internal structure of an HRB600E high-nitrogen anti-seismic steel bar, which comprises the following steps of: melting a steel billet which contains a V element and has high nitrogen content of 200-320ppm by adopting high-temperature heating (ensuring high-temperature section time), and uniformly solidifying phases VN and V (CN); original coarse grains are crushed by large rolling reduction of rolling passes for grain refinement; a VN and V (CN) precipitation peak interval of 870-710 DEG C is utilized, the cooling speed is controlled to be 2.0-3.2 DEG C / s, and a VN and V (CN) precipitation phase of 120-650 nm is obtained to the maximum extent; and in a bainite transformation interval of 690-500 DEG C, the cooling speed is reduced so as to obtain 5-10% of bainite. The extensibility and the tensile strength of the material are improved through fine grain strengthening, structure strengthening and precipitation strengthening, and the anti-seismic property of the 600MPa-level steel bar is optimized.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of threaded steel production processes, in particular to a production method of an HRB600E high-nitrogen anti-seismic steel bar structure and the steel bar structure. BACKGROUND

[0002] In the new standard (Steel for Reinforced Concrete, Part 2: Hot Rolled Ribbed Steel Bar) GB / T 1499.2-2018) of threaded steel, there is only one 600MPa steel grade: HRB600, and the steel grade has no anti-seismic performance requirements. With the expansion of the application of high-strength steel bars, especially in the earthquake-prone areas of China, there is a strong demand for the anti-seismic performance of steel bars.

[0003] The new standard of threaded steel nitrogen (GB / T 1499.2-2018) has clear provisions for the content of N element: “7.2.3 The nitrogen content of the steel shall not be greater than 0.012%, and the supplier may not analyze it if it can be guaranteed. There are enough nitrogen-binding elements in the steel, and the nitrogen content limit can be appropriately relaxed”. That is, by adding V, Nb, Ti, Al and other strong nitrogen-binding elements to the steel, the nitrogen content of the steel can be greater than 0.012wt%.

[0004] Vanadium V is a strong nitrogen-binding element, which plays a strong precipitation strengthening and grain refinement role in steel, improving the strength and toughness of the steel. However, V is a rare element and expensive, and if it is only used for precipitation strengthening, the cost performance is too low.

[0005] Through the retrieval of domestic related databases and network information, it is found that the articles such as “Preparation Process Research of HRB600E High-strength Anti-seismic Steel Bar” (Qiao Guoping et al., Liaoning University of Science and Technology, July 2019), “Technical Progress and Application of Vanadium Micro-alloyed Steel” (Yang Caifu et al., Journal of Iron and Steel Research, December 2020), “Influence of Nb Content and Process on the Microstructure and Properties of HRB600E Steel Bar” (Pan Hongbo et al., Journal of Building Materials, March 2017) and the patents such as “High-strength Anti-seismic Steel Bar HRB600E and Production Method Thereof” (China CN 114990429A, Mou Lijun Zhang Qun et al.), “Method for Improving the Yield Ratio of High-strength Hot Rolled Ribbed Steel Bar” (China CN 111893371 A, Xiao Jinfu Wang Weifei et al.), “HRB600E High-strength Threaded Steel and Production Method Thereof” (China CN 116875898 A, Li Xuefeng Liu Hongyin et al.), “HRB600E High-strength Anti-seismic Steel Bar and Production Method Thereof” (China, CN 108913995 A, Zhi Xubowang Jinle et al.) have been found.

[0006] These articles describe the trial production process of 600 MPa grade threaded steel, such as the influence of vanadium and nitrogen content range on performance, and the influence of steel structure on yield ratio, but do not describe how to obtain nanoscale VN and a small amount of bainite structure in the steel and process control measures. The patent of "a high-strength anti-seismic steel bar HRB600E and its production method" mainly describes the steel composition design, wherein V: 0.10-0.15%, N: 0.015-0.025%, without controlling the steel structure and precipitates in the rolling process. The patent of "a method for improving the yield ratio of high-strength hot-rolled ribbed steel bars" mainly describes the V: 0.065-0.09% and N: 0.013-0.017% content in the HRB600E steel bar, and the VN gradually precipitates during rolling and cooling process, which refines the structure and hinders the lattice dislocation movement, thereby improving the strength and toughness of the steel; but it does not set the control technology of VN precipitation temperature and the amount and size of precipitates. The patent of "a HRB600E high-strength threaded steel and its production method" mainly describes the billet heating temperature of 1100-1200℃, the water cooling of the intermediate billet after intermediate rolling, and the cumulative deformation rate control of the intermediate billet finishing mill group at 20-40%, and the temperature of the finishing mill group is 750-930℃, that is, the low-temperature rolling in the non-recrystallization region of austenite is used to adjust the size ratio of grains in different directions of the rolled material to improve the yield ratio of the threaded steel; but it does not set the influence of VN precipitation and structure proportion change on the yield ratio. The patent of "a HRB600E high-strength anti-seismic steel bar and its production method" mainly describes the increase of Cr element to reduce the V content (Cr: 0.20-0.50%, V: 0.060-0.080%), and does not propose a control range for N content, so it does not set the VN precipitation and control technology measures. SUMMARY

[0007] In order to overcome the defects of the prior art and meet the demand for anti-seismic performance of high-strength steel bars, the application discloses a production method for controlling the structure of HRB600E high-nitrogen anti-seismic steel bars, which obtains the HRB600E anti-seismic steel bars with good elongation performance and high yield ratio by adopting high-temperature heating, RCR rolling process, strengthening nanoscale VN precipitation and expanding the proportion of bainite.

[0008] The first aspect of the application provides a production method for the structure of high-nitrogen anti-seismic steel bars, which comprises the following steps:

[0009] (1) heating: heating the cast billet containing V element and having a N content of 200-320 ppm;

[0010] (2) rolling: adopting large reduction multi-pass rolling by using a recrystallization process;

[0011] (3) cooling: controlling the cooling speed of the steel bar in the range of 870-710℃ to be 2.0-3.2℃ / s, and controlling the cooling speed of the steel bar in the range of 690-500℃ to be 3.0-5.0℃ / s.

[0012] According to the production method of the first aspect, in step (1), the casting blank contains, by mass percentage, C: 0.23-0.28 wt%, Si: 0.65-0.80 wt%, Mn: 1.45-1.60 wt%, P: ≤0.040 wt%, S: ≤0.040 wt%, V: 0.100-0.120 wt%, Nb: 0.010-0.025 wt%, N: 0.020-0.032 wt%, and the balance being iron and unavoidable impurity elements, and Ceq: ≤0.58%.

[0013] According to the production method of the first aspect, in step (1), the high-temperature stage time of 1200-1270°C during the heating process is ≥70 min; and / or

[0014] The total heating time is ≥110 min.

[0015] According to the production method of the first aspect, in step (2), the rough rolling temperature is 1110-1160°C; and / or

[0016] The finish rolling temperature is 1020-1060°C.

[0017] According to the production method of the first aspect, in step (2), the rough rolling pass number is not less than 4 passes, preferably 4-6 passes, and most preferably 6 passes.

[0018] According to the production method of the first aspect, in step (2), the reduction of the first and second passes is 21-25%, and the reduction of any one or more passes after the first and second passes is 28-40%.

[0019] Preferably, the reduction of the fourth pass is 28-40%.

[0020] The second aspect of the present application provides a high-nitrogen anti-vibration steel bar structure prepared according to the production method of the first aspect.

[0021] According to the high-nitrogen anti-vibration steel bar structure of the second aspect, the high-nitrogen anti-vibration steel bar structure is composed of ferrite, pearlite, and bainite.

[0022] According to the high-nitrogen anti-vibration steel bar structure of the second aspect, the proportion of bainite in the steel bar structure is 5%-10%.

[0023] Preferably, the proportion of ferrite in the steel bar structure is 35-55%; and / or

[0024] Preferably, the proportion of pearlite in the steel bar structure is 40%-52%.

[0025] The high-nitrogen anti-seismic reinforcing steel bar organization according to the second aspect has VN precipitated phase particle size of 120-650nm;

[0026] Preferably, the VN precipitated phase particles in the steel bar organization are uniformly and diffusely distributed.

[0027] The present application aims at: ①controlling the nano-level VN precipitated quantity, and the specific precipitated phase size is 120-650nm; ②increasing the 5-10% bainite organization.

[0028] The present application is different from the prior art in that: ①the original VN grains are melted for a long time at high temperature and uniformly distributed; ②the original grains are broken and the recrystallized grains are refined by large reduction; ③the rolling piece cooling speed is reduced to 870-710℃, so as to precipitate more and finer VN precipitated phase; ④the bainite transformation time is controlled to increase the bainite quantity in the steel.

[0029] The production method of the present application has the following beneficial effects, but is not limited to:

[0030] 1. Refining the grain size: the actual measurement data shows that the HRB600E produced by the present technology has the grain size increased by 0.8 grade compared with the steel produced by the prior art.

[0031] 2. Enhancing the elongation performance of the steel bar, and the maximum total elongation rate Agt index is increased by 1%.

[0032] 3. Strengthening the anti-seismic performance of the steel bar, the strength yield ratio Rm / Rel index is increased by 0.02, and the fluctuation range of the strength yield ratio is reduced by 0.015.

[0033] The present application provides a production process using the steel billet high-nitrogen content, high-temperature heating, large reduction rolling, controlling the fine VN precipitated quantity, and prolonging the bainite transformation time, and particularly relates to the fine-grain strengthening, precipitated strengthening, organization strengthening and precipitation strengthening technology to produce the HRB600E with excellent comprehensive performance. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 The electron microscope graph of the Φ32mm specification HRB600E steel bar organization of Example 3 is shown.

[0035] Figure 2 The microstructure graph of the Φ32mm specification HRB600E steel bar organization of Example 3 is shown. DETAILED DESCRIPTION

[0036] The present application will be further described in detail by the drawings and examples. Through these descriptions, the features and advantages of the present application will become more clear and explicit.

[0037] The term "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other implementations. Unless specifically indicated otherwise, the drawings are not necessarily to scale.

[0038] In addition, the technical features involved in different embodiments of the present application described below can be combined with each other as long as there is no conflict.

[0039] The present application provides a production method of high-nitrogen anti-seismic reinforcing steel bar structure, comprising the following steps:

[0040] (1) heating: heating a casting blank containing V element and N content of 200-320 ppm;

[0041] (2) rolling: adopting large reduction amount recrystallization process to carry out multi-pass rolling;

[0042] (3) cooling: controlling the cooling speed of the reinforcing steel bar in the range of 870-710 DEG C to be 2.0-3.2 DEG C / s, and controlling the cooling speed of the reinforcing steel bar in the range of 690-500 DEG C to be 3.0-5.0 DEG C / s.

[0043] In one embodiment, in step (1), the casting blank contains, in terms of mass percentage, C: 0.23-0.28 wt%, Si: 0.65-0.80 wt%, Mn: 1.45-1.60 wt%, P: ≤0.040 wt%, S: ≤0.040 wt%, V: 0.100-0.120 wt%, Nb: 0.010-0.025 wt%, N: 0.020-0.032 wt%, and the balance is iron and inevitable impurity elements, and Ceq: ≤0.58%. Wherein Ceq (%) can be calculated according to the following formula:

[0044] Ceq = C + Mn / 6 + (Cr + V + Mo) / 5 + (Cu + Ni) / 15 In a specific embodiment, the size range of the casting blank of the present application is 150x150-180x180 mm.

[0045] The present application adopts low-V high-N (V: 0.10-0.12%, N: 0.02-0.032%) screw steel blank, adopts high-temperature heating, large reduction amount recrystallization rolling (RCR), controls nanoscale VN precipitation strengthening, expands the proportion of bainite structure, etc. rolling technology, through VN fine-grain strengthening, structure strengthening, precipitation strengthening and precipitation strengthening effect, so that the strength, ductility and anti-seismicity of HRB600E steel material all reach the best.

[0046] VN in the rolled piece gradually precipitates from the austenite grain boundary at 1100℃, and forms a precipitation peak in the range of 870-710℃. If the cooling speed is reduced, i.e. the precipitation time is prolonged, more precipitates can be obtained. In addition, the lower the precipitation temperature, the smaller the size of the precipitates, which is beneficial to the elongation of the steel bar.

[0047] Similarly, prolonging the bainite transformation time can obtain more bainite and improve the strength of the steel bar.

[0048] In one embodiment, in step (1), the time of the high-temperature section of 1200-1270℃ during the heating process is ≥70 min; and / or

[0049] The total heating time is ≥110 min.

[0050] When the continuous casting blank is solidified, VN is segregated and forms particles in the blank due to the principle of fractional crystallization. These VN particles are difficult to melt the matrix, so the heating temperature of the high-nitrogen blank is high, especially the time of the high-temperature section is long, to ensure that the large VN particles melt into the matrix and are uniformly distributed.

[0051] In one embodiment, in step (2), the starting rolling temperature is 1110-1160℃; and / or

[0052] The final rolling temperature is 1020-1060℃.

[0053] In one embodiment, in step (2), the rolling passes are not less than 4 passes, preferably 4-6 passes, and most preferably 6 passes.

[0054] In one embodiment, in step (2), the reduction of the first and second passes is 21-25%, and the reduction of any pass or multiple passes after the first and second passes is 28-40%.

[0055] Preferably, the reduction of the fourth pass is 28-40%.

[0056] Large reduction recrystallization rolling (RCR process) is to crush the original VN particles by large pass deformation to form fine austenite recrystallization. The fine austenite grains are transformed into pearlite at high temperature and bainite at medium temperature. The present application realizes the refinement of austenite grains by RCR process, and improves the performance and durability of the material.

[0057] The present application also provides a high-nitrogen anti-vibration steel bar structure prepared according to the above production method.

[0058] In one embodiment, the high-nitrogen anti-vibration steel bar structure is composed of ferrite, pearlite and bainite.

[0059] In a specific embodiment, the proportion of bainite in the steel structure is 5% to 10%;

[0060] Preferably, the proportion of ferrite in the steel structure is 35% to 55%; and / or

[0061] Preferably, the proportion of pearlite in the steel structure is 40% to 52%.

[0062] In an embodiment, the VN precipitated phase particle size in the steel structure is 120 to 650 nm;

[0063] Preferably, the VN precipitated phase particles in the steel structure are uniformly and diffusely distributed.

[0064] In a specific embodiment, the steel billet heating process parameters are controlled as shown in the following table:

[0065]

[0066] Note: The high-temperature section time refers to the time for heating the casting billet at a temperature in the range of 1200 to 1270°C.

[0067] High-temperature and large-rolling reduction process (RCR process) is adopted: the reduction amount of the 4th rolling mill in the rough rolling mill train is set to 28 to 40% (conventional process reduction amount: 21 to 25%), which is used to break the original coarse austenite grains and VN grains and recrystallize them; the finish rolling temperature is set to 1020 to 1060°C.

[0068] In the temperature range of 870 to 710°C (conventional process cooling speed: 3 to 5°C / s), the rolling piece cooling speed is controlled to be 2.0 to 3.2°C / s, so as to ensure sufficient time for precipitating a large amount of VN and V(CN) particles, the VN precipitated phase particle size is 120 to 650 nm, and the particles are uniformly and diffusely distributed.

[0069] In the temperature range of 690 to 500°C (conventional process cooling speed: 2 to 3°C / s), the rolling piece cooling speed is controlled to be 3.0 to 5.0°C / s, so as to promote the medium-temperature bainite transformation through fast cooling, ensure that the steel structure is outside the ferrite and pearlite, obtain 5 to 10% bainite, and improve the strength of the steel bar.

[0070] Example 1

[0071] 1) The cross-sectional size of the continuous casting billet is 165 x 165 mm;

[0072] Elemental composition of the cast slab: C: 0.27wt%, Si: 0.74wt%, Mn: 1.53wt%, P: 0.027wt%, S: 0.005wt%, V: 0.109wt%, Nb: 0.025wt%, N: 263ppm (0.0263wt%), balance iron and inevitable impurity elements, Ceq: 0.55%.

[0073] 2) The heating and rolling parameters of the cast slab are shown in Table 1:

[0074] Table 1 Heating and rolling parameters of the cast slab of Example 1

[0075]

[0076]

[0077] Note: The high-temperature stage time refers to the time for heating the cast slab at a temperature in the range of 1200-1270°C.

[0078] 3) RCR process: the pass reduction amount of the 4th rolling mill in the rough rolling mill set (total of 6 rolling mills) is 32.5%; the finish rolling temperature is set to be 1032°C.

[0079] 4) The rolling diameter of the HRB600E straight bar is 20mm, the rolling piece cooling speed at 803°C is 2.7°C / s, the VN precipitated phase particle size of the finished product sample is measured to be 212-375nm, the average value is 280.4nm, and the electron microscope shows that the VN precipitated phase is uniformly distributed.

[0080] 5) The rolling piece cooling speed at 569°C is 4.1°C / s, the finished product sample has the following structure proportion: ferrite 45.4%, pearlite 48%, and bainite 6.6%.

[0081] 6) The measured mechanical properties of the steel bar are as follows: Rel: 665MPa, Rm: 850MPa, Agt: 12.7%, and Rm / Rel strength yield ratio: 1.28.

[0082] Example 2:

[0083] 1) The cross-sectional size of the continuous cast slab is 150x150mm;

[0084] Elemental composition of the cast slab: C: 0.28wt%, Si: 0.76wt%, Mn: 1.55wt%, P: 0.022wt%, S: 0.004wt%, V: 0.102wt%, Nb: 0.02wt%, N: 218ppm (0.0218wt%), balance iron and inevitable impurity elements, Ceq: 0.56%.

[0085] 2) The heating and rolling parameters of the cast slab are shown in Table 2:

[0086] Table 2: Slab heating and rolling parameters of Example 2

[0087]

[0088]

[0089] Note: The high-temperature stage time refers to the time for heating the slab at a temperature in the range of 1200-1270°C.

[0090] 3) RCR process: the pass reduction amount of the 4th rolling mill in the rough rolling mill train (total of 6 rolling mills): 28.7%; the finish rolling temperature was set to be 1021°C.

[0091] 4) The diameter of the rolled piece was 8 mm, the cooling speed of the rolled piece at 710°C was 2.0°C / s, the VN precipitated phase particle size of the finished product sample was measured to be 125-240 nm, the average value was 198.3 nm, and the electron microscope showed that the VN precipitated phase was uniformly distributed.

[0092] 5) The cooling speed of the rolled piece at 506°C was 3.2°C / s, the proportion of the microstructure of the finished product sample was: ferrite 38.9%, pearlite 51.4%, and bainite 9.7%.

[0093] 6) The mechanical properties of the steel bar were measured to be: Rel: 680 MPa, Rm: 890 MPa, Agt: 13.4%, and the ratio of Rm / Rel: 1.31.

[0094] Example 3:

[0095] 1) The cross-sectional size of the continuous casting slab was: 180x180 mm;

[0096] The partial element composition of the slab was: C: 0.26wt%, Si: 0.72wt%, Mn: 1.56wt%, P: 0.021wt%, S: 0.007wt%, V: 0.118wt%, Nb: 0.021wt%, N: 307ppm (0.0307wt%), and the balance was iron and inevitable impurity elements, Ceq: 0.54%.

[0097] 2) The slab heating and rolling parameters are shown in Table 3:

[0098] Table 3: Slab heating and rolling parameters of Example 3

[0099] Item Standard Measured value First heating section ≤900℃ 887℃ Second heating section 1160～1250℃ 1234℃ Soaking section 1220～1270℃ 1267℃ Total heating time ≥ 110 min 180 min High temperature section time ≥ 70 min 115 min Breakdown temperature 1110～1160℃ 1154℃ Temper mill temperature 930～980℃ 976℃

[0100] Note: The high-temperature stage time refers to the time for heating the slab at a temperature in the range of 1200-1270°C.

[0101] 3) RCR process: rough rolling mill set (6 rolling mills in total) 4th rolling mill pass reduction: 36%; final rolling temperature setting: 1055°C.

[0102] 4) Rolling diameter 40mm HRB600E straight bar, rolling piece cooling speed at 870°C: 3.2°C / s, Figure 1 The electron microscope image of the Φ32mm specification HRB600E steel bar of Example 3 is shown, and the VN precipitated phase particle size of the finished product sample is measured to be 166nm-642nm, with an average of 415.3nm, and the electron microscope shows that the VN precipitated phase is uniformly distributed.

[0103] 5) Rolling piece cooling speed at 685°C: 5.0°C / s, Figure 2 The microstructure image of the Φ32mm specification HRB600E steel bar of Example 3 is shown, the white blocky part is ferrite, the black and gray part is pearlite, and the black punctate part distributed on the ferrite is bainite, and the finished product sample has a microstructure proportion of 54.5% ferrite, 40.2% pearlite, and 5.3% bainite.

[0104] 6) The measured mechanical properties of the steel bar are Rel: 630MPa, Rm: 800MPa, Agt: 11.3%, and Rm / Rel strength yield ratio: 1.27.

[0105] Example 4:

[0106] 1) The continuous casting billet has a cross-sectional size of 150x175mm;

[0107] The element composition of the billet is C: 0.27wt%, Si: 0.77wt%, Mn: 1.54wt%, P: 0.023wt%, S: 0.005wt%, V: 0.115wt%, Nb: 0.024wt%, N: 280ppm (0.0280wt%), and the balance is iron and unavoidable impurity elements, Ceq: 0.55%.

[0108] 2) The billet heating and rolling parameters are shown in Table 4:

[0109] Table 4 Billet heating and rolling parameters of Example 4

[0110] Item Standard Measured value First heating section ≤900℃ 806℃ Second heating section 1160～1250℃ 1174℃ Soaking section 1220～1270℃ 1225℃ Total heating time ≥ 110 min 130 min High temperature section time ≥ 70 min 72 min Breakdown temperature 1110～1160℃ 1117℃ Temper mill temperature 930～980℃ 958℃

[0111] Note: The high temperature section time refers to the time of heating the billet at a temperature in the range of 1200-1270°C.

[0112] 3) RCR process: rough rolling mill set (6 rolling mills in total) 4th rolling mill pass reduction: 35%; final rolling temperature setting: 1022°C.

[0113] 4) Rolling diameter 12mm HRB600E straight bar, rolling piece cooling speed at 750℃: 2.3℃ / s, VN precipitate particle size measured by product sample: 192-303nm, average value: 238.6nm, electron microscopy shows that VN precipitates are uniformly distributed.

[0114] 5) Rolling piece cooling speed at 600℃: 4.0℃ / s, product sample structure ratio: ferrite 46.4%, pearlite 46.2%, bainite 7.4%.

[0115] 6) Actual measured mechanical properties of steel bars: Rel: 670MPa, Rm: 845MPa, Agt: 9.9%, Rm / Rel

[0116] Yield ratio: 1.26.

[0117] The performance of examples 1-4 and conventional HRB600E steel is shown in Table 5, which is tested according to GB / T1499.2-2018 "Steel for reinforced concrete·Part 2: Hot-rolled ribbed steel bars" standard.

[0118] Table 5 Comparison of performance of inventive steel examples and conventional HRB600E (diameter: Φ8mm-Φ32mm)

[0119]

[0120] Note: 1. Example 2 steel is Φ8mm coil, examples 1, 3 and 4 are straight coils.

[0121] 2.A gt , R°m / R°el, R°el / Rel are all seismic index parameters of deformed steel bars, wherein, A gt is the maximum total elongation, R°m / R°el is the ratio of the measured tensile strength to the measured yield strength of the steel bar, and R°el / Rel* is the ratio of the measured yield strength to the standard yield strength.

[0122] 3. The conventional process comparison is the average value of 20mm HRB600E produced by non-patent process.

[0123] As can be seen from Table 5, the steel materials of different specifications prepared by examples 1-4 of the present application can all meet the standard requirements. In particular, compared with the steel materials prepared by conventional process, examples 1-4 of the present application have smaller VN size, even example 3 with the largest steel bar diameter of 32mm, due to its slow cooling speed, the precipitate particle size is larger than that of small diameter steel bars of examples 1, 2 and 4, but smaller than that of the steel bar with diameter of 20mm prepared by conventional process, which shows that more and finer VN precipitates are precipitated by the production method of the present application.

[0124] The application has been described above with reference to preferred embodiments. However, these embodiments are merely exemplary and are presented for purposes of illustration only. Variations and modifications to the application can be made based on what is described herein by a person of ordinary skill in the art. Such variations and modifications are considered to be within the scope of the application.

Claims

1.A method for producing a high-nitrogen anti-vibration steel bar structure, comprising the following steps: (1) heating: heating a casting blank containing V element and having a N content of 200-320 ppm; (2) rolling: performing multi-pass rolling using a large reduction amount recrystallization process; and (3) cooling: controlling the cooling speed of the steel bar to be 2.0-3.2 ℃ / s in the range of 870-710 ℃ and 3.0-5.0 ℃ / s in the range of 690-500 ℃. In step (1), the casting blank contains, by mass percentage, C: 0.23-0.28 wt%, Si: 0.65-0.80 wt%, Mn: 1.45-1.60 wt%, P: ≤0.040 wt%, S: ≤0.040 wt%, V: 0.100-0.120 wt%, Nb: 0.010-0.025 wt%, N: 0.020-0.032 wt%, and the balance being iron and unavoidable impurity elements, and Ceq: ≤0.58%. In step (1), the high-temperature stage time of 1200-1270 ℃ during the heating process is ≥70 min; and / or the total heating time is ≥110 min. In step (2), the starting rolling temperature is 1110-1160 ℃; and / or the finishing rolling temperature is 1020-1060 ℃. In step (2), the rolling rough rolling pass is not less than 4 passes, preferably 4-6 passes, and most preferably 6 passes. In step (2), the reduction amount of the first and second passes is 21-25%, and the reduction amount of any one or more passes after the first and second passes is 28-40%. Preferably, the reduction amount of the fourth pass is 28-40%. The high-nitrogen anti-vibration steel bar structure is prepared according to the method of any one of claims 1 to 6. The high-nitrogen anti-vibration steel bar structure is composed of ferrite, pearlite and bainite. The proportion of bainite in the steel bar structure is 5%-10%. Preferably, the proportion of ferrite in the steel bar structure is 35-55%; and / or the proportion of pearlite in the steel bar structure is 40%-52%. The VN precipitated phase particle size in the steel bar structure is 120-650 nm. Preferably, the VN precipitated phase particles in the steel bar structure are uniformly and dispersedly distributed. ​ ​ ​ 2. The production method according to claim 1, characterized by, ​ 3. The production method according to claim 1, characterized by, ​ ​ 4. The production method according to claim 1, characterized by, ​ ​ 5. The method of claim 1, wherein, ​ 6. The method of claim 5, wherein, ​ ​ 7. A high nitrogen anti-seismic reinforcing bar structure, characterized by, ​ 8. The high nitrogen anti-seismic rebar structure of claim 7, wherein, ​ 9. The high nitrogen anti-seismic rebar structure of claim 8, wherein, ​ ​ ​ 10. The high nitrogen anti-seismic rebar structure of claim 7, wherein, ​ ​

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