Ultrahigh-strength corrosion-resistant anchor rod steel and production method thereof

Abstract

The application relates to an ultrahigh-strength corrosion-resistant anchor rod steel bar and a production method thereof. The anchor rod steel bar comprises an anchor rod body and a corrosion-resistant plating layer. The anchor rod body comprises the following components in mass fraction: carbon 0.21-0.26%, manganese 1.55-1.75%, vanadium 0.20-0.30%, nitrogen 0.015-0.035%, niobium 0.15-0.55%, titanium 0.1-0.2%; residual elements phosphorus <=0.02%, sulfur <=0.01%; and the rest is iron and inevitable impurities. The application has the effects of improving the strength, plasticity and toughness and corrosion resistance of the anchor rod steel bar.

Description

Technical Field

[0001] This application relates to the field of metallurgical material preparation technology, and in particular to an ultra-high strength corrosion-resistant anchor bar and its production method. Background Technology

[0002] More than 80% of my country's coal is mined underground, and the mining depth is increasing at a rate of 8-12 meters per year, with many mines reaching depths of 1000-1500 meters. As the mining depth increases, the pressure in the mines also increases, making the safety and stability of roadway support increasingly important.

[0003] Rock bolts are rod-shaped structures anchored within coal or rock masses to maintain the stability of the surrounding rock. Rock bolt support is the preferred and safest primary support method for coal mine roadways. Compared to other support methods, it is an active support form with advantages such as simple support technology, good support effect, low material consumption and support cost, and convenient transportation and construction. In roadway, soil and rock, and slope support projects, rock bolts play a crucial role as the main metal support material, and their durability and service life are widely valued.

[0004] However, the underground environment of coal mines is complex, with fluctuating temperature and humidity, and complex compositions of media such as air and mine water. Anchor bolts are susceptible to corrosion from their environment, primarily atmospheric corrosion, water corrosion, and media corrosion. Corroded anchor bolts can break, leading to mine collapses, causing significant personal safety accidents and economic losses, thus requiring improvement. Summary of the Invention

[0005] To improve the strength and corrosion resistance of anchor rod reinforcement, this application provides an ultra-high strength corrosion-resistant anchor rod reinforcement and its production method.

[0006] This application provides an ultra-high strength anchor bar and its production method, which adopts the following technical solution:

[0007] In a first aspect, this application provides an ultra-high strength corrosion-resistant anchor rod and its production method, which adopts the following technical solution: An ultra-high strength corrosion-resistant anchor rod, characterized in that: it includes an anchor rod body and an anti-corrosion coating, wherein the anchor rod body comprises the following components in parts by mass: carbon 0.21-0.26%, manganese 1.55-1.75%, vanadium 0.20-0.30%, nitrogen 0.015-0.035%, niobium 0.15-0.55%, titanium 0.1-0.2%; residual elements phosphorus ≤0.02%, sulfur ≤0.01%; the remainder being iron and unavoidable impurities.

[0008] Vanadium is a microalloying element with stable chemical properties and readily combines with nitrogen to produce precipitation strengthening, which can improve the strength and toughness of anchor bars. Niobium's solid solution and precipitation affect the microstructure evolution during the production process of the steel bars. The carbonitrided precipitates of niobium can pin the grain boundary phase, thereby preventing austenite grain growth and refining the grain size of the anchor bars, thus improving their strength and toughness. Titanium can combine with carbon and nitrogen to precipitate dispersed fine precipitates. The synergistic effect of vanadium, niobium, and titanium, three microalloying elements, refines the grain size of the anchor bars, improving their strength, toughness, and corrosion resistance.

[0009] Preferably, the ultra-high strength corrosion-resistant anchor bar also includes a rare earth deoxidizing agent.

[0010] Rare earth elements have strong deoxidizing and desulfurizing properties. By reducing irregular oxygen and sulfur inclusions in anchor bars, they can reduce microcracks caused by stress concentration due to irregularly shaped inclusions. Rare earth deoxidizing and desulfurizing agents are added to molten iron and combine with oxygen and sulfur elements. They precipitate at high temperatures. Some of them are discharged by floating, while the rest are small rare earth inclusions that are dispersed in the anchor bars. They have the effects of fine grain strengthening and precipitation strengthening, which can improve the strength, ductility, toughness and corrosion resistance of anchor bars.

[0011] Preferably, the rare earth deoxidizing agent comprises a cerium-iron alloy.

[0012] Ferrocene alloys have good deoxidation and desulfurization properties. Cerium can refine the grain size, promote the precipitation of carbon and nitrides of vanadium, niobium and titanium, and improve the strength, toughness and corrosion resistance of anchor bars.

[0013] Preferably, the mass percentage of cerium in the anchor bolt body of the cerium-iron alloy is 0.01-0.03%.

[0014] Anchor bars prepared according to the above percentage content have high strength, high plasticity and toughness, and good corrosion resistance.

[0015] Preferably, the anti-corrosion coating includes a tungsten alloy coating and a modified aluminum-zinc coating. The tungsten alloy coating is obtained by electroplating with a tungsten alloy electroplating solution, and the modified aluminum-zinc coating is obtained by hot-dip galvanizing.

[0016] The double-layer anti-corrosion coating enhances the corrosion resistance of the anchor rod reinforcement. The tungsten alloy coating has good density and excellent bonding strength, which can reduce the porosity of the coating, isolate and protect the anchor rod body, and improve the bonding strength of the coating. The modified aluminum-zinc coating has good corrosion resistance through modification treatment and has good bonding strength with the tungsten alloy coating, which can improve the stability, strength and toughness of the anchor rod reinforcement.

[0017] Preferably, the tungsten alloy electroplating solution comprises: nickel aminosulfonate, sodium tungstate, cobalt sulfate, sodium citrate, potassium chloride, and boric acid.

[0018] Nickel sulfamate provides nickel, sodium tungstate provides tungsten, and cobalt sulfate provides cobalt. The three metal elements work synergistically to improve the bonding strength and corrosion resistance between the tungsten alloy coating and the anchor rod body.

[0019] Preferably, the modified aluminum-zinc coating comprises the following components in parts by weight: 55% aluminum, 1.4% silicon, 0.4-0.5% modifier, and the balance being zinc.

[0020] The corrosion resistance of the modified zinc-aluminum coating was improved by treatment with a modifier.

[0021] Preferably, the modifier is a titanium-rhenium alloy.

[0022] Titanium-rhenium alloy has high strength, low density and good corrosion resistance. By doping the zinc-aluminum coating with rhenium-titanium alloy, the stability of the zinc-aluminum alloy can be improved, thereby improving the corrosion resistance of the anchor rod reinforcement.

[0023] Secondly, this application provides a production method for ultra-high strength corrosion-resistant anchor rod reinforcement, which adopts the following technical solution:

[0024] A method for producing ultra-high strength corrosion-resistant anchor rod reinforcement bars comprises the following steps:

[0025] The steel billet is smelted in a converter according to the nominal composition, then refined in a ladle, continuously cast to obtain a steel billet, heated in a heating furnace, and then subjected to rough rolling, intermediate rolling, water cooling, temperature-controlled finishing rolling, water-controlled cooling and natural cooling in a cooling bed to obtain the anchor bolt body;

[0026] The electroplating solution was prepared according to the tungsten alloy electroplating solution formula. The anchor rod body was degreased. A steel sheet was used as the cathode and a nickel plate was used as the anode to electroplat the anchor rod body, resulting in an electroplated anchor rod.

[0027] The modified zinc-aluminum coating is smelted according to its composition formula. Under the protection of a reducing atmosphere, the electroplated anchor rod is immersed in the molten modified zinc-aluminum coating for hot-dip galvanizing treatment. After passivation, it is dried so that the anti-corrosion coating adheres to the surface of the anchor rod body, resulting in ultra-high strength corrosion-resistant anchor rod steel bars.

[0028] The anchor bars prepared according to the above steps have good corrosion resistance, strength, and ductility.

[0029] Preferably, the instantaneous cooling rate of the water-controlled cooling is 200-220℃ / s.

[0030] Cooling at the above-mentioned cooling rate can effectively promote the precipitation of precipitates, regulate the morphology of precipitates, and synergistically enhance the grain refinement effect with cerium, thereby improving the strength, toughness, and corrosion resistance of anchor rods.

[0031] In summary, this application includes at least one of the following beneficial technical effects:

[0032] 1. Vanadium is a microalloying element with stable chemical properties and readily combines with nitrogen to produce precipitation strengthening, which can improve the strength of anchor bars. Niobium's solid solution and precipitation affect the microstructure evolution during the production process of the steel bars. The carbonitrided precipitates of niobium can pin the grain boundary phase, thereby preventing austenite grain growth, refining the grain size of the anchor bars, and thus improving their strength. Titanium can combine with carbon and nitrogen to precipitate dispersed fine precipitates. The synergistic effect of vanadium, niobium, and titanium as microalloying elements refines the grain size of the anchor bars, improving their strength, ductility, toughness, and corrosion resistance.

[0033] 2. Rare earth elements have strong deoxidizing and desulfurizing properties. By reducing irregular oxygen and sulfur inclusions in anchor bars, they can reduce microcracks caused by stress concentration due to irregularly shaped inclusions. Rare earth deoxidizing and desulfurizing agents are added to molten iron and combine with oxygen and sulfur elements. They precipitate at high temperatures. Some of them are discharged by floating, while the small rare earth inclusions generated are dispersed in the anchor bars, which have the effects of fine grain strengthening and precipitation strengthening, thus improving the strength and corrosion resistance of the anchor bars.

[0034] 3. The modifier improves the stability of the modified zinc-aluminum coating. The anti-corrosion coating enhances the corrosion resistance of the anchor rod through the synergistic effect between the tungsten alloy coating and the modified zinc-aluminum coating. Detailed Implementation

[0035] This application discloses an ultra-high strength corrosion-resistant anchor bar and its production method. The following detailed description is provided in conjunction with the embodiments:

[0036] Example

[0037] Example 1

[0038] The steel is smelted in a converter according to the nominal composition, with rare earth deoxidizers added, so that the percentage content of various elements in the molten steel is: carbon 0.21%, manganese 1.55%, vanadium 0.20%, nitrogen 0.015%, niobium 0.15%, titanium 0.1%, and cerium 0.01%; the residual elements are phosphorus ≤0.02% and sulfur ≤0.01%; the remainder is iron and unavoidable impurities. The molten steel after converter smelting is refined in a ladle with nitrogen bottom blowing for 20 minutes at a flow rate of 220 L / min and a pressure of 0.8 MPa. Steel billets are then produced by continuous casting and heated in a walking beam furnace for 2 hours at a soaking temperature of 1070℃. Finally, a rolling process is performed. The roughing rolling temperature is 1050℃. Water cooling is used before intermediate and finishing rolling to control the finishing rolling inlet temperature at 900℃. Temperature-controlled finishing rolling is conducted, with the finishing rolling exit speed controlled at 15 m / s. After finishing rolling, water cooling is performed, adjusting the water flow rate and pressure in the water tank to achieve an instantaneous cooling rate of 200℃ / s. The temperature before the upper cooling bed is controlled at 400℃. After natural cooling on the cooling bed, the anchor bolt body is obtained.

[0039] The electroplating solution was prepared according to the formula for tungsten alloy plating, with the following concentrations: nickel sulfamate 0.3 mol / L, sodium tungstate 0.1 mol / L, cobalt sulfate 0.05 mol / L, sodium citrate 0.5 mol / L, potassium chloride 25 g / L, and boric acid 40 g / L. The anchor bolt body was degreased. A steel sheet was used as the cathode, and a nickel plate as the anode, with the current density controlled at 3.5 A / dm³. 2 The electroplating temperature is 80℃ and the electroplating time is 1 hour. The anchor rod body is electroplated to obtain the electroplated anchor rod.

[0040] The modified zinc-aluminum coating was smelted according to its composition formula: 55 kg of aluminum, 1.4 kg of silicon, 0.4 kg of modifier and 43.2 kg of zinc were mixed and smelted. Under the protection of hydrogen and carbon monoxide, the electroplated anchor rod was immersed in the modified zinc-aluminum coating melt for hot-dip galvanizing treatment. The hot-dip galvanized anchor rod body was then immersed in a 30% phosphoric acid aqueous solution and passivated in a 60°C water bath for 10 min. After drying at 60°C for 30 min, ultra-high strength corrosion-resistant anchor rod steel bar was obtained.

[0041] Example 2

[0042] The steel is smelted in a converter according to the nominal composition, with rare earth deoxidizers added, so that the percentage content of various elements in the molten steel is: carbon 0.26%, manganese 1.75%, vanadium 0.30%, nitrogen 0.035%, niobium 0.55%, titanium 0.2%, and cerium 0.03%; the residual elements are phosphorus ≤0.02% and sulfur ≤0.01%; the remainder is iron and unavoidable impurities. The molten steel after converter smelting is refined in a ladle with nitrogen bottom blowing for 20 minutes at a flow rate of 220 L / min and a pressure of 0.8 MPa. Steel billets are then produced by continuous casting and heated in a walking beam furnace for 2 hours at a soaking temperature of 1070℃. Finally, a rolling process is performed. The roughing rolling temperature is 1050℃. Water cooling is used before intermediate and finishing rolling to control the finishing rolling inlet temperature at 900℃. The finishing rolling exit speed is controlled at 15 m / s. After finishing rolling, water cooling is applied, with the instantaneous cooling rate of the steel reinforcement reaching 220℃ / s by adjusting the water flow rate and pressure. The temperature before the upper cooling bed is controlled at 400℃. After natural cooling on the cooling bed, the anchor bolt body is obtained.

[0043] The electroplating solution was prepared according to the formula for tungsten alloy plating, with the following concentrations: nickel sulfamate 0.3 mol / L, sodium tungstate 0.1 mol / L, cobalt sulfate 0.05 mol / L, sodium citrate 0.5 mol / L, potassium chloride 25 g / L, and boric acid 40 g / L. The anchor bolt body was degreased. A steel sheet was used as the cathode, and a nickel plate as the anode, with the current density controlled at 3.5 A / dm³. 2 The electroplating temperature is 80℃ and the electroplating time is 1 hour. The anchor rod body is electroplated to obtain the electroplated anchor rod.

[0044] The modified zinc-aluminum coating was smelted according to its composition formula: 55 kg of aluminum, 1.4 kg of silicon, 0.5 kg of modifier and 43.1 kg of zinc were mixed and smelted. Under the protection of hydrogen and carbon monoxide, the electroplated anchor rod was immersed in the modified zinc-aluminum coating melt for hot-dip galvanizing treatment. The hot-dip galvanized anchor rod body was then immersed in a 30% phosphoric acid aqueous solution and passivated in a 60°C water bath for 10 min. After drying at 60°C for 30 min, ultra-high strength corrosion-resistant anchor rod steel bar was obtained.

[0045] Example 3

[0046] The steel is smelted in a converter according to the nominal composition, with rare earth deoxidizers added, so that the percentage content of various elements in the molten steel is: carbon 0.235%, manganese 1.65%, vanadium 0.25%, nitrogen 0.025%, niobium 0.35%, titanium 0.15%, and cerium 0.02%; the residual elements are phosphorus ≤0.02% and sulfur ≤0.01%; the remainder is iron and unavoidable impurities. The molten steel after converter smelting is refined in a ladle with nitrogen bottom blowing for 20 minutes at a flow rate of 220 L / min and a pressure of 0.8 MPa. Steel billets are then produced by continuous casting and heated in a walking beam furnace for 2 hours at a soaking temperature of 1070℃. Finally, a rolling process is performed. The roughing rolling temperature is 1050℃. Water cooling is used before intermediate and finishing rolling to control the finishing rolling inlet temperature at 900℃. Temperature-controlled finishing rolling is conducted, with the finishing rolling exit speed controlled at 15 m / s. After finishing rolling, water cooling is performed again. By adjusting the water flow rate and pressure in the water tank, the instantaneous cooling rate of the reinforcing bar is 210℃ / s. The temperature before the upper cooling bed is controlled at 400℃. After natural cooling on the cooling bed, the anchor bolt body is obtained.

[0047] The electroplating solution was prepared according to the formula for tungsten alloy plating, with the following concentrations: nickel sulfamate 0.3 mol / L, sodium tungstate 0.1 mol / L, cobalt sulfate 0.05 mol / L, sodium citrate 0.5 mol / L, potassium chloride 25 g / L, and boric acid 40 g / L. The anchor bolt body was degreased. A steel sheet was used as the cathode, and a nickel plate as the anode, with the current density controlled at 3.5 A / dm³. 2 The electroplating temperature is 80℃ and the electroplating time is 1 hour. The anchor rod body is electroplated to obtain the electroplated anchor rod.

[0048] The modified zinc-aluminum coating was smelted according to its composition formula: 55 kg of aluminum, 1.4 kg of silicon, 0.45 kg of modifier and 43.15 kg of zinc were mixed and smelted. Under the protection of hydrogen and carbon monoxide, the electroplated anchor rod was immersed in the modified zinc-aluminum coating melt for hot-dip galvanizing treatment. The hot-dip galvanized anchor rod body was then immersed in a 30% phosphoric acid aqueous solution and passivated in a 60°C water bath for 10 min. After drying at 60°C for 30 min, ultra-high strength corrosion-resistant anchor rod steel bar was obtained.

[0049] Example 4

[0050] Example 4 is based on Example 3. The only difference between Example 4 and Example 3 is that the cerium content in Example 4 is 0.005%.

[0051] Example 5

[0052] Example 5 is based on Example 3. The only difference between Example 5 and Example 3 is that the cerium content in Example 5 is 0.04%.

[0053] Example 6

[0054] Example 6 is based on Example 3. The only difference between Example 6 and Example 3 is that rare earth deoxidizing agents are not added in Example 6.

[0055] Example 7

[0056] Example 7 is based on Example 3. The only difference between Example 7 and Example 3 is that the amount of modifier used in the hot-dip galvanizing step in Example 7 is 0.3 kg.

[0057] Example 8

[0058] Example 8 is based on Example 3. The only difference between Example 8 and Example 3 is that the amount of modifier used in the hot-dip galvanizing step in Example 8 is 0.6 kg.

[0059] Example 9

[0060] Example 9 is based on Example 3. The only difference between Example 9 and Example 3 is that no modifier is added in the hot-dip galvanizing step in Example 9.

[0061] Example 10

[0062] Example 10 is based on Example 3. The only difference between Example 10 and Example 3 is that no electroplating process is performed in Example 10.

[0063] Example 11

[0064] Example 11 is based on Example 3. The only difference between Example 11 and Example 3 is that hot-dip galvanizing is not performed in Example 11.

[0065] Example 12

[0066] Example 12 is based on Example 3. The only difference between Example 12 and Example 3 is that the instantaneous cooling rate of water-controlled cooling in Example 12 is 180°C / s.

[0067] Example 13

[0068] Example 13 is based on Example 3. The only difference between Example 13 and Example 3 is that the instantaneous cooling rate in Example 12 is 250°C / s.

[0069] Comparative Example 1

[0070] Comparative Example 1 is based on Example 3. The only difference between Comparative Example 1 and Example 3 is that vanadium is not added in Comparative Example 1.

[0071] Comparative Example 2

[0072] Comparative Example 2 is based on Example 3. The only difference between Comparative Example 2 and Example 3 is that niobium is not added in Comparative Example 2.

[0073] Comparative Example 3

[0074] Comparative Example 3 is based on Example 3. The only difference between Comparative Example 3 and Example 3 is that titanium is not added in Comparative Example 3.

[0075] Performance testing

[0076] (1) Select GB / T 228-2002 Metallic Materials - Tensile Testing at Room Temperature as the standard. Apply tensile force through a tensile testing machine, gradually increase the tensile force, and record the load-strain curve of the specimen. The stress value corresponding to the yield point is the yield strength. The maximum stress value that the specimen can withstand before breaking is the tensile strength. Measure and record the length of the specimen before and after tensile fracture, calculate the elongation, and record the results in Table 1.

[0077] (2) The standard GB / T19746-2018 Corrosion Salt Solution Immersion Test of Metals and Alloys was selected as the standard. The test specimens were prepared and the specimens were subjected to immersion test in a simulated humid atmospheric environment. The test solution was a 1 g / L hydrogen sulfide salt solution. After immersion for 3 weeks, the weight of the specimens before and after the test was recorded, the corrosion rate was calculated, and the results were recorded in Table 1.

[0078] Table 1. Test results of strength, ductility, toughness and corrosion resistance of anchor reinforcement.

[0079]

[0080] As shown in Table 1, the yield strength of Examples 1-3 is greater than 733 MPa, the tensile strength is greater than 959 MPa, the elongation is greater than 22%, and the corrosion rate is less than 0.067 g / (m²). 2 ·h), thus it can be seen that the anchor rod steel prepared in this application has good strength, ductility and toughness and corrosion resistance.

[0081] As shown in Table 1, the differences between Examples 4, 5, and 6 and Example 3 are only as follows: the cerium content in Example 4 is 0.005%, the cerium content in Example 5 is 0.04%, no rare earth deoxidizer is added in Example 6, and the cerium content in Example 3 is 0.02%. The yield strength, tensile strength, elongation, and corrosion rate in Examples 4, 5, and 6 are all less than 717 MPa, less than 934 MPa, less than 21%, and greater than 0.072 g / (m²). 2 In Example 3, the yield strength was 753 MPa, the tensile strength was 981 MPa, the elongation was 24%, and the corrosion rate was 0.059 g / (m²). 2Compared with Example 3, Examples 4, 5, and 6 all showed a decrease in strength, ductility, toughness, and corrosion resistance. This is because the cerium content was not within the specified range. Too little cerium had limited deoxidation and desulfurization effects, resulting in reduced inclusions and coarser grains in the anchor rod. Too much cerium would affect the morphology of the grain boundary phase. Without the addition of rare earth deoxidizers, the oxygen and sulfur content in the anchor rod increased, the grains became larger, and there was a lack of fine grain strengthening and precipitation strengthening effects, thus reducing the strength, ductility, toughness, and corrosion resistance of the anchor rod.

[0082] As shown in Table 1, the differences between Examples 7, 8, and 9 and Example 3 are only as follows: the amount of modifier used in the hot-dip galvanizing step in Example 7 is 0.3 kg; the amount of modifier used in the hot-dip galvanizing step in Example 8 is 0.6 kg; and no modifier is added in the hot-dip galvanizing step in Example 9. The yield strength, tensile strength, elongation, and corrosion rate in Examples 7, 8, and 9 are all less than 749 MPa, less than 952 MPa, less than 21%, and greater than 0.092 g / (m²). 2 Compared with Example 3, Examples 7, 8, and 9 all showed a decrease in strength, ductility, toughness, and corrosion resistance. This is because the amount of modifier used was not within the specified range. Too little modifier had limited effect on enhancing corrosion resistance, while too much modifier would actually increase the corrosion rate. Without modifier, the corrosion resistance was further reduced, and none of these methods could achieve good corrosion resistance. The synergistic effect of the tungsten alloy coating and the modified zinc-aluminum coating was weakened, resulting in a decrease in the corrosion resistance of the anchor rod reinforcement.

[0083] As shown in Table 1, the differences between Examples 10 and 11 and Example 3 are only as follows: no electroplating was performed in Example 10, no hot-dip galvanizing was performed in Example 11, and the yield strength, tensile strength, elongation, and corrosion rate of Examples 10 and 11 are less than 736 MPa, less than 937 MPa, less than 19%, and greater than 0.137 g / (m²). 2 Compared with Examples 10 and 11, the strength, toughness and corrosion resistance of the anchor rods decreased. This is because without electroplating or hot-dip galvanizing, the synergistic effect of the tungsten alloy coating and the modified zinc-aluminum coating is lacking, resulting in a decrease in the corrosion resistance of the anti-corrosion coating and a weakening of its protective effect on the anchor rod body, thus reducing the corrosion resistance of the anchor rod reinforcement.

[0084] As shown in Table 1, the only difference between Examples 12 and 13 and Example 3 is that the instantaneous cooling rate of water-controlled cooling in Example 12 is 180℃ / s, and the instantaneous cooling rate of water-controlled cooling in Example 13 is 250℃ / s. The yield strength of Examples 12 and 13 is less than 721 MPa, the tensile strength is less than 935 MPa, the elongation is less than 20%, and the corrosion rate is greater than 0.102 g / (m²). 2Compared with Example 3, Example 12, 13 and Example 3 all showed a decrease in strength, ductility, toughness and corrosion resistance. This is because the instantaneous cooling rate of the water-controlled cooling is not within the specified range. Too fast or too slow cooling rate will affect the amount and morphology of precipitated phases, reduce the ability to refine grains, and thus reduce the strength, ductility, toughness and corrosion resistance of the anchor rod.

[0085] As shown in Table 1, the differences between Comparative Examples 1, 2, and 3 and Example 3 are only as follows: vanadium is not added in Comparative Example 1, niobium is not added in Comparative Example 2, and titanium is not added in Comparative Example 3. In Comparative Example 1, the yield strength is less than 685 MPa, the tensile strength is less than 832 MPa, the elongation is less than 15%, and the corrosion rate is greater than 0.107 g / (m²). 2 Compared with Comparative Examples 1, 2, 3 and Example 3, the strength, ductility, toughness and corrosion resistance of the anchor rod steel bars all decreased significantly. This is because the absence of any one of the three elements, vanadium, niobium or titanium, weakens the synergistic effect between the elements, resulting in larger grains and a significant decrease in the strength, ductility, toughness and corrosion resistance of the anchor rod steel bars.

[0086] This specific embodiment is merely an explanation of this application and is not intended to limit it. Based on the above description, those skilled in the art can make various changes and modifications without departing from the technical concept of this application. The technical scope of this application is not limited to the contents of the specification but must be determined according to the scope of the claims.

Claims

1. A type of ultra-high strength corrosion-resistant anchor rod reinforcement, characterized in that: The anchor bolt body comprises an anchor bolt body and an anti-corrosion coating. The anchor bolt body comprises the following components by mass percentage: carbon 0.21-0.26%, manganese 1.55-1.75%, vanadium 0.20-0.30%, nitrogen 0.015-0.035%, niobium 0.15-0.55%, and titanium 0.1-0.2%; residual elements phosphorus ≤0.02% and sulfur ≤0.01%; the remainder being iron and unavoidable impurities. The anti-corrosion coating includes a tungsten alloy coating and a modified aluminum-zinc coating. The tungsten alloy coating is obtained by electroplating with a tungsten alloy electroplating solution, and the modified aluminum-zinc coating is obtained by hot-dip galvanizing. The tungsten alloy electroplating solution includes: nickel aminosulfonate, sodium tungstate, cobalt sulfate, sodium citrate, potassium chloride, and boric acid; The modified aluminum-zinc coating comprises the following components by mass percentage: 55% aluminum, 1.4% silicon, 0.4-0.5% modifier, and the balance being zinc; The modifier is a titanium-rhenium alloy; The production process of the ultra-high strength corrosion-resistant anchor steel bars adopts the following steps: The steel billet is smelted in a converter according to the nominal composition, then refined in a ladle, continuously cast to obtain a steel billet, heated in a heating furnace, and then subjected to rough rolling, intermediate rolling, water cooling, temperature-controlled finishing rolling, water-controlled cooling and natural cooling in a cooling bed to obtain the anchor bolt body; The electroplating solution was prepared according to the tungsten alloy electroplating solution formula. The anchor rod body was degreased. A steel sheet was used as the cathode and a nickel plate was used as the anode to electroplat the anchor rod body, resulting in an electroplated anchor rod. The modified zinc-aluminum coating is smelted according to its composition formula. Under the protection of a reducing atmosphere, the electroplated anchor rod is immersed in the molten modified zinc-aluminum coating for hot-dip galvanizing treatment. After passivation, it is dried so that the anti-corrosion coating adheres to the surface of the anchor rod body, resulting in ultra-high strength corrosion-resistant anchor rod steel bars. The instantaneous cooling rate of the water-controlled cooling system is 200-220℃ / s.

2. The ultra-high strength corrosion-resistant anchor rod reinforcement according to claim 1, characterized in that: The ultra-high strength corrosion-resistant anchor steel also includes rare earth deoxidizing and desulfurizing agents.

3. The ultra-high strength corrosion-resistant anchor rod reinforcement according to claim 2, characterized in that: The rare earth deoxidizing agent includes cerium-iron alloy.

4. The ultra-high strength corrosion-resistant anchor rod reinforcement according to claim 3, characterized in that: The mass percentage of cerium in the anchor bolt body of the cerium-iron alloy is 0.01-0.03%.

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