Chloride ion corrosion resistant hot rolled ribbed bar HRB500cE and processing technology

Abstract

The invention belongs to the field of ribbed steel bars, and relates to a chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE and a processing technology, the chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE comprises the following components by mass percentage: less than or equal to 0.10% of carbon, 0.50%-0.60% of silicon, 0.8%-1.50% of manganese, less than or equal to 0.020% of phosphorus, less than or equal to 0.020% of sulfur, 2.0%-3.0% of chromium, 0.35%-0.60% of nickel, 0.29%-0.52% of copper, 0.05%-0.10% of vanadium, and the balance iron.

Description

Technical Field

[0001] The invention belongs to the field of ribbed steel bars, and relates to a hot-rolled ribbed steel bar HRB500cE resistant to chloride ion corrosion and a processing technology. Background Art

[0002] At present, reinforced concrete structure is still one of the main structures in modern buildings. Bridges, buildings, roads, docks and other buildings are inseparable from reinforced concrete structure. However, reinforced concrete structures often begin to show deterioration phenomena such as cracks and steel corrosion after a short period of use, and require a lot of money for regular repair and maintenance. About 50% of the corrosion maintenance costs in developed countries are used to repair damage to concrete structures caused by steel corrosion. Therefore, how to effectively protect reinforced concrete structures and improve their corrosion resistance is a major issue of common research and concern at home and abroad.

[0003] In recent years, China has also accelerated the research on steel bar anti-corrosion. However, while the traditional galvanizing method improves corrosion resistance, its processing method is cumbersome, and the transportation and construction process are prone to damage to the coating. The production efficiency is low, and the reliability is closely related to the construction level, making it difficult to promote and use on a large scale. There is little research on low-cost corrosion-resistant steel bars in China, so it is necessary to develop a low-cost, high-corrosion-resistant, and corrosion-resistant steel bar with excellent mechanical properties. Based on ordinary steel bars, this paper reasonably controls the addition of elements such as Cr, Ni, and Cu, and adopts the process of "water penetration during the process + air cooling after rolling" to develop a low-cost chloride ion corrosion-resistant steel bar. The mechanical properties of the corrosion-resistant steel bar meet the 500MPa grade steel bar standard, and it also has excellent chloride ion corrosion resistance. Summary of the invention

[0004] In order to overcome the defects in the above-mentioned related technologies, on the one hand, the present invention provides a hot-rolled ribbed steel bar HRB500cE resistant to chloride ion corrosion.

[0005] To achieve the above technical purpose, the present invention provides a chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE. The chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE comprises the following components by mass percentage: carbon ≤ 0.10%, silicon 0.50% to 0.60%, manganese 0.8% to 1.50%, phosphorus ≤ 0.020%, sulfur ≤ 0.020%, chromium 2.0% to 3.0%, nickel 0.35% to 0.60%, copper 0.29% to 0.52%, vanadium 0.05% to 0.10%, and the balance is iron.

[0006] On the other hand, the present invention also provides a production process of hot-rolled ribbed steel bar HRB500cE resistant to chloride ion corrosion, which is suitable for the production of the above-mentioned hot-rolled ribbed steel bar HRB500cE resistant to chloride ion corrosion. The production process of hot-rolled ribbed steel bar HRB500cE resistant to chloride ion corrosion comprises the following steps: Obtain molten iron from blast furnaces; The blast furnace hot metal is desulfurized by the KR method. Rough refining in the converter, pouring the molten iron into the ladle and bottom blowing, nitrogen blowing and stirring in the early stage of bottom blowing, argon blowing and stirring in the middle and late stages, the carbon content in the molten iron is controlled to be greater than 0.05% at the end of bottom blowing, and the overoxidation of the molten steel is strictly controlled, and deoxidation alloy is added to the ladle at the same time; LF refining, the ladle is transferred to the refining furnace, and diffusion deoxidation and submerged arc refining are carried out, and then argon is soft-blown into the ladle for no less than 15 minutes; Continuous casting, control the superheat of molten iron at 15-30℃, the baking temperature is greater than or equal to 1000℃, and electromagnetic stirring is used for continuous casting cooling in slow cooling mode. The temperature before straightening is greater than or equal to 900℃.

[0007] After continuous casting is completed, the production process of the chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE also includes rolling, the heating section temperature is controlled at 1120±20°C, the soaking section temperature is controlled at 1160±20°C, the furnace time is ≥120 minutes, the start rolling temperature is 1040±20°C, the finish rolling temperature is 930±10°C, and air cooling is performed after rolling.

[0008] During the rolling process, pre-water treatment is carried out, and water is penetrated after rolling. The cooling method after rolling is air cooling, and the cooling rate is controlled at 1-2℃ / s.

[0009] Micro-pile or micro-drawing rolling is adopted for rough and medium rolling, and looper tension-free rolling is adopted for finishing rolling to avoid drawing steel rolling.

[0010] The beneficial effects of the present invention are: Compared with the prior art, the present invention optimizes the smelting process by optimizing the alloy component system. Bottom blowing nitrogen stirring can be used in the early stage of the converter blowing process, and pure argon stirring can be switched to in the middle and late stages. The converter tapping temperature is controlled between 1610°C and 1630°C. A ladle with good air permeability is used, bottom blowing nitrogen or argon is opened 1-2 minutes before tapping, and large-volume stirring is performed during the tapping process to ensure that the alloy is fully melted. A clean turnover ladle is used to ensure that the red ladle is tapped, and the ladle baking temperature is >900℃; slag blocking is used to tap steel, and a large amount of slag is prevented, and the thickness of the slag layer in the ladle is <50mm; silicon manganese, composite deoxidizer, vanadium nitrogen alloy, etc. are used for deoxidation and alloying in the ladle, and argon is blown and stirred at the bottom during the tapping process; lime + composite refining slag is used for slag making, and the refining process ensures the refining submerged arc operation; the superheat is controlled to be 15-35℃, and the working layer of the middle ladle uses magnesium dry material, and the baking temperature is ≥1000℃; a long water nozzle can be used from the large ladle to the middle ladle and a sealing cover can be used for the middle ladle to reduce temperature drop and secondary oxidation; acid-resistant steel special protective slag is used for the middle ladle to the crystallizer protective slag, and the protective slag must be dry and black-faced, and the principle of less, more frequent and more uniform is implemented; electromagnetic stirring is used in the production process, and the continuous casting cooling adopts a slow cooling mode, which reduces the water volume by 10% compared with the conventional cooling; the temperature before straightening is ≥900℃. The new component system is designed by the present invention, the content of elements such as Cr, Ni, and Cu is optimized, and the strength index of the steel bar is improved. The process of "water penetration during rolling + air cooling after rolling" is adopted to reasonably control the heating temperature, rolling start temperature, finishing rolling temperature, cooling bed temperature and cooling method, so that the steel bar structure is low-carbon bainite, and the corrosion-resistant steel bar obtains good strength, toughness and corrosion resistance, which fully meets the national standard requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0012] Figure 1 This is a production process flow chart of the chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE of the present invention; Figure 2 This is the crystal phase diagram of the hot-rolled ribbed steel bar HRB500cE resistant to chloride ion corrosion according to the present invention; Figure 3 This is a picture of the outer rust layer of the hot-rolled ribbed steel bar HRB500cE resistant to chloride ion corrosion according to the present invention after being corroded for 72 hours; Figure 4 This is a picture of the inner rust layer of the chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE described in the present invention after corrosion for 72 hours. DETAILED DESCRIPTION

[0013] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0014] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0015] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more. Example

[0016] like Figures 2 to 4 As shown, the chemical composition of a chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE, by mass percentage, includes C: 0.073%, Si: 0.50%, Mn: 0.97%, P: 0.016%, S: 0.013%, Cr: 2.52%, Ni: 0.366%, Cu: 0.293%, V: 0.08%, and the balance is Fe.

[0017] Chloride ion corrosion resistant hot rolled ribbed steel bar HRB500cE with a diameter of 28mm was subjected to a cyclic immersion corrosion test under the following test conditions: The solution temperature is controlled at 43~47℃, the baking and drying temperature is 69~72℃, the humidity in the box is 65~73%RH, each cycle is 60min, including 12min of immersion and 48min of exposure, the test solution is 2% NaCl solution with a pH of 7.1. The test duration is 72 hours.

[0018] The above-mentioned hot-rolled ribbed steel bar HRB500cE resistant to chloride ion corrosion was divided into five groups for testing, and the corrosion rates were 4.36g / (m 2 +h)、4.56g / (m2 +h)、4.22g / (m 2 +h)、4.27g / (m 2 +h)、4.35g / (m 2 + h).

[0019] The present invention solves the problem that the chloride ion corrosion-resistant steel bars cannot have both corrosion resistance and mechanical properties by controlling the on-site rolling process and the contents of alloy elements such as C, Si, Mn, Cr, Ni, Cu, and V, taking into account the strengthening and corrosion resistance mechanism of each element and combining the actual on-site process operation.

[0020] Comparative Example 1 The chemical composition of a hot-rolled ribbed steel bar HRB500E, measured by mass percentage, includes C: 0.25%, Si: 0.68%, Mn: 1.5%, P: 0.028%, S: 0.023%, Cr: 0.021%, Ni: 0.007%, Cu: 0.01%, V: 0.0665%, and the balance is Fe.

[0021] Hot rolled ribbed steel bar HRB500E with a diameter of 28 mm was subjected to a cyclic immersion corrosion test under the following conditions: The solution temperature is controlled at 43~47℃, the baking and drying temperature is 69~72℃, the humidity in the box is 65~73%RH, each cycle is 60min, including 12min of immersion and 48min of exposure, the test solution is 2% NaCl solution with a pH of 7.1. The test duration is 72 hours.

[0022] The hot-rolled ribbed steel bar HRB500E was divided into five groups for testing, and the corrosion rates were 7.48g / (m 2 +h)、7.44g / (m 2 +h)、7.31g / (m 2 +h)、7.49g / (m 2 +h)、7.37g / (m 2 + h).

[0023] It can be seen that the chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE described in the present application has stronger corrosion resistance to chloride ions than the hot-rolled ribbed steel bar HRB500E.

[0024] On the other hand, Figure 1 As shown, the present invention also provides a production process of hot-rolled ribbed steel bar HRB500cE resistant to chloride ion corrosion, comprising the following steps: (1) The industrial process flow is: KR hot metal pretreatment → 100-ton converter → LF refining → 150×150mm square billet continuous casting machine → stack cooling → billet inspection → heating in heating furnace → high-pressure descaling → rough rolling → 1# shearing head → intermediate rolling → 2# shearing head and tail → pre-finishing rolling → 3# shearing head and tail → pre-water cooling → finishing rolling → 4# shearing → air cooling on cooling bed → sizing → inspection and point support → bundling / weighing / labeling → storage.

[0025] The blast furnace molten iron conditions are controlled as follows: Si: 0.30-0.50%, P: ≤0.14%, S: ≤0.030%, temperature ≥1350°C. The KR desulfurization process strictly follows the process regulations and the slag is removed as cleanly as possible.

[0026] Rough refining in converter: Use high-quality scrap steel to reduce the mixing of impurities; Control the appropriate gun position during converter refining, control the process splashing, and use the bottom blowing function to ensure that the molten steel does not over-oxidize when the end point C is appropriate; Control the appropriate feeding time during converter refining, and add slag in small batches and multiple batches. The slag must be added within 5 minutes of refining to achieve early slagging in the early stage and thorough slagging during the process; The final slag basicity is controlled at R=2.8~3.2, and the end point gun pressure time is>30 s; Bottom blowing nitrogen stirring can be used in the early stage of converter refining, and pure argon stirring can be switched in the middle and late stages; End point control: C>0.05%, strengthen carbon and oxygen accumulation control, and strictly control molten steel overoxidation; The converter tapping temperature is controlled between 1610℃ and 1630℃, and the end point temperature can be appropriately increased by 10-30℃ according to the ladle condition and abnormal conditions; Use a ladle with good air permeability and air permeability, open bottom blowing nitrogen or argon 1-2 minutes before tapping, and stir with a large amount of air during the tapping process to ensure that the alloy is fully melted. Use clean turnover ladle to ensure red ladle tapping, ladle baking temperature>900℃; slag blocking tapping to prevent large amount of slag, slag layer thickness in the ladle<50mm; deoxidation alloying: silicon manganese, composite deoxidizer, vanadium nitrogen alloy, etc. are used for deoxidation alloying in the ladle; alloy is added when one quarter of the steel is discharged, silicon manganese, composite deoxidizer, vanadium nitrogen alloy, etc. are added in sequence, and all are added when three quarters of the molten steel is discharged; slag washing for tapping: lime, silica and slag washing materials are added with the steel flow during the tapping process, the reference addition amount is 5~6kg / t steel, and the addition time is one quarter of the steel is discharged, together with the alloy; argon blowing and stirring at the bottom of the whole tapping process, attention should be paid to the control of stirring intensity during the stirring process, and attention should be paid to ensuring that the temperature requirements before argon are met; after the ladle arrives at the argon station, it should be blown for 3 minutes to take samples, and after adjusting the composition, argon should be blown for 2 minutes before hanging the ladle for refining.

[0027] (2) LF refining operation: When the ladle arrives for refining, immediately measure the temperature and pass argon. The argon pressure and flow rate should be such that the slag surface is slightly turned over without exposing the molten steel. Take samples after the first electrode is lowered and adjust the composition according to the composition. Refining slag control: Use lime and fluorite to make slag, and silicon carbide, calcium carbide, and aluminum chips for diffusion deoxidation and refining submerged arc operation. Quickly turn the slag into white slag. After the composition and temperature are qualified, soft argon blowing is carried out, and the soft blowing time shall not be less than 15 minutes.

[0028] (3) Continuous casting operation: properly control the superheat to 15-30℃; use magnesium dry material for the working layer of the tundish, and the baking temperature is ≥1000℃; use a long nozzle from the large ladle to the tundish and a sealing cover for the tundish to reduce temperature drop and secondary oxidation; use an aluminum carbon immersion nozzle from the tundish to the crystallizer to ensure verticality and centering. The insertion depth of the immersion nozzle is 90±10 mm; the crystallizer protective slag uses a special protective slag for low-carbon acid-resistant steel. The protective slag must be dry and black-faced, and the principle of less, more frequent and more uniform is implemented; electromagnetic stirring is used in the production process; the continuous casting cooling adopts a slow cooling mode, which reduces the water volume by 10% compared with conventional cooling; the temperature before straightening is ≥900℃; ensure that the nozzle is not blocked, the water spray is uniform, and the position is centered to ensure the quality of the steel billet.

[0029] In some embodiments, the production process of chloride ion corrosion resistant hot rolled ribbed steel bar HRB500cE comprises the following steps: Process flow: KR molten iron pretreatment → 100-ton converter → LF refining → 150×150mm square billet continuous casting machine → pile cooling → billet inspection → heating in heating furnace → high-pressure descaling → rough rolling → 1# shearing head → medium rolling → 2# shearing head and tail → pre-finishing rolling → 3# shearing head and tail → pre-water cooling → finishing rolling → 4# shearing → cooling bed air cooling → fixed length → inspection, point support → bundling / weighing / hanging → warehousing.

[0030] 2. The chemical composition shall conform to the chemical composition of chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE specified in GB / T 33953-2017 or other standards, but the composition needs to be controlled as follows: C: ≤0.10%, Si: 0.50-0.60%, Mn: 0.8-1.50%, P: ≤0.020%, S: ≤0.020%, Cr: 2.0-3.0%, Ni: 0.35-0.60%, Cu: 0.3-0.52%, V: 0.05-0.10%, the balance is Fe and unavoidable impurities.

[0031] 3. The blast furnace molten iron conditions are controlled as follows: Si: 0.30-0.50%, P: ≤0.14%, S: ≤0.030%, temperature ≥1350℃. The KR desulfurization process strictly follows the process regulations and the slag is removed as cleanly as possible.

[0032] 4. Rough refining in converter: Use high-quality scrap steel to reduce impurities; control the appropriate gun position during converter refining, control process splashing, and use the bottom blowing function to ensure that the molten steel does not over-oxidize while ensuring that the end point C is appropriate; control the appropriate feeding time during converter refining, and add slag in small batches and multiple batches. The slag must be added within 5 minutes of refining to ensure early slag formation in the early stage and thorough slag formation during the process; the final slag basicity is controlled at R=2.8~3.2, and the end point gun pressure time is>30s; End point control: C>0.05%, strengthen carbon-oxygen accumulation control, and strictly control molten steel overoxidation; the converter tapping temperature is controlled between 1610℃ and 1630℃, and the end point temperature can be appropriately increased by 10-30℃ according to the ladle condition and abnormal conditions.

[0033] 5. LF refining furnace refining: When the ladle arrives for refining, immediately measure the temperature and pass argon. The argon pressure and flow rate should be such that the slag surface is slightly turned over without exposing the molten steel. Take samples after the first electrode is lowered and adjust the composition according to the composition. Refining slag control: Use lime and fluorite to make slag, and silicon carbide, calcium carbide, and aluminum chips for diffusion deoxidation and refining submerged arc operation. Quickly turn the slag into white slag. After the composition and temperature are qualified, soft argon blowing is carried out, and the soft blowing time shall not be less than 15 minutes.

[0034] 6. Continuous casting operation: properly control the superheat to 15-30℃; magnesium dry material is used in the working layer of the tundish, and the baking temperature is ≥1000℃; long nozzles are used from the large ladle to the tundish and sealing covers are used in the tundish to reduce temperature drop and secondary oxidation; aluminum carbon immersion nozzles are used from the tundish to the crystallizer to ensure verticality and centering. The insertion depth of the immersion nozzle is 90±10 mm; the crystallizer protective slag uses low-carbon acid-resistant steel special protective slag, and electromagnetic stirring is used in the production process; the continuous casting cooling adopts the slow cooling mode, which reduces the water volume by 10% compared with the conventional cooling; the temperature before straightening is ≥900℃; ensure that the nozzle is not blocked, the water spray is uniform, and the position is centered to ensure the quality of the steel billet.

[0035] 7. The bar rolling mill is used for rolling, the heating furnace is a walking beam heating furnace, and the billet heating temperature is controlled: the temperature of the heating section is controlled at 1120±20℃, the temperature of the soaking section is controlled at 1160±20℃, and the time in the furnace is ≥120 minutes.

[0036] 8. The hot rolling final rolling temperature is controlled at 870-950℃, and the rolling specification is φ12mm-φ32mm.

[0037] 9. After rolling, cool on the cooling bed at a cooling rate of 1℃ / s-2℃ / s. When cooled to 500℃-550℃, take off the cooling bed and use pile cooling at a cooling rate of 0.05℃ / s-1℃ / s to cool to room temperature.

[0038] 10. Other matters not covered here shall be controlled in accordance with the existing bar product production process.

[0039] Compared with existing corrosion-resistant steels, the present invention controls the alloy content and key smelting parameters and adopts the process of "appropriate temperature heating + controlled cooling after rolling", which can make the steel mainly form bainite structure + ferrite structure, and refine the grains, thereby improving the strength and plasticity of the bar. The product performance fully meets the requirements of GB / T 33953-2017 for 500MPa grade chloride ion corrosion-resistant hot-rolled ribbed steel bars.

[0040] The present invention solves the problem that the chloride ion corrosion-resistant steel bars cannot have both corrosion resistance and mechanical properties by optimizing the alloy component system, optimizing the smelting process, controlling the on-site rolling process and the contents of alloy elements such as C, Si, Mn, Cr, Ni, Cu, and V, considering the strengthening and corrosion resistance mechanism of each element, and combining the actual on-site process operation.

[0041] By optimizing the content of elements such as Cr, V, and Ni, the grain size of steel can be refined and the strength index of steel bars can be improved. By optimizing the content of elements such as Cr, Cu, and Ni, the grain size of steel can be refined and the corrosion resistance of steel bars can be improved. The process of "high-pressure water descaling + slow cooling after rolling" is adopted to reasonably control the heating temperature, the starting rolling temperature, the finishing rolling temperature, the cooling bed temperature, and the cooling method, so that the precipitation of low cooling rate ferrite is affected, the nucleation driving force of bainite transformation is increased, and the occurrence of bainite transformation is promoted. The microstructure in the steel is transformed into granular bainite and lath bainite structure, and the number of MA islands as the "hard phase" increases and is dispersed, and granular bainite can be seen. The steel bar structure is a mixture of ferrite and bainite, which obtains good strength, toughness and corrosion resistance, and fully meets the requirements of national standards.

[0042] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0043] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A hot-rolled ribbed steel bar HRB500cE resistant to chloride ion corrosion, characterized in that: The chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE includes the following components by mass percentage: carbon ≤0.10%, silicon 0.50%~0.60%, manganese 0.8%~1.50%, phosphorus ≤0.020%, sulfur ≤0.020%, chromium 2.0%~3.0%, nickel 0.35%~0.60%, copper 0.29%~0.52%, vanadium 0.05%~0.10%, and the balance is iron.

2. A production process of chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE, suitable for the production of chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE as claimed in claim 1, characterized in that: The production process of the chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE comprises the following steps: Obtain molten iron from blast furnaces; The blast furnace hot metal is desulfurized by the KR method. Rough refining in the converter, pouring the molten iron into the ladle and bottom blowing, nitrogen blowing and stirring in the early stage of bottom blowing, argon blowing and stirring in the middle and late stages, the carbon content in the molten iron is controlled to be greater than 0.05% at the end of bottom blowing, and the overoxidation of the molten steel is strictly controlled, and deoxidation alloy is added to the ladle at the same time; LF refining, the ladle is transferred to the refining furnace, and diffusion deoxidation and submerged arc refining are carried out, and then argon is soft-blown into the ladle for no less than 15 minutes; Continuous casting, control the superheat of molten iron at 15-30℃, the baking temperature is greater than or equal to 1000℃, and electromagnetic stirring is used for continuous casting cooling in slow cooling mode. The temperature before straightening is greater than or equal to 900℃.

3. The production process of chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE according to claim 2, characterized in that: After continuous casting is completed, the production process of the chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE also includes rolling, the heating section temperature is controlled at 1120±20°C, the soaking section temperature is controlled at 1160±20°C, the furnace time is ≥120 minutes, the start rolling temperature is 1040±20°C, the finish rolling temperature is 930±10°C, and air cooling is performed after rolling.

4. The production process of chloride ion corrosion resistant hot-rolled ribbed steel bar HRB500cE according to claim 3, characterized in that: During the rolling process, pre-water treatment is carried out, and water is penetrated after rolling. The cooling method after rolling is air cooling, and the cooling rate is controlled at 1-2℃ / s.

5. The production process of hot-rolled ribbed steel bar HRB500cE resistant to chloride ion corrosion according to claim 4, characterized in that: Micro-pile or micro-drawing rolling is adopted for rough and medium rolling, and looper tension-free rolling is adopted for finishing rolling to avoid steel drawing rolling.

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