Corrosion-resistant anchor bolt

Abstract

The application relates to the technical field of fasteners, and discloses a corrosion-resistant foundation bolt, which is obtained through cold upsetting, thread processing and phosphating treatment of a blank, and the blank is composed of the following components in percentage by weight: C 0.33%-0.51%, Mn 0.4%-0.7%, Cr 1.3%-2.5%, Al 1.2%-4.8%, Zr 1.2%-4.9%, Nb 2.8%-4.8%, P<=0.015%, S<=0.01%, and the rest is Fe and other inevitable impurities. Through the technical scheme, the problems of poor corrosion resistance and tensile strength of the foundation bolt in the related art are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fasteners, in particular, relates to a corrosion-resistant anchor bolt. BACKGROUND

[0002] With the acceleration of the process of industrial modernization and the continuous progress of technology, as an important mechanical equipment fixing component, anchor bolts play a key role in various engineering projects. Anchor bolts are not only widely used in traditional industrial facilities, such as equipment installation in power, chemical, manufacturing and other industries, but also play an indispensable role in emerging clean energy fields, such as photovoltaic power generation, wind power generation and other power station construction.

[0003] The corrosion resistance and tensile strength of the anchor bolt directly affect the stability of the mechanical equipment. With the increasingly harsh service environment of the anchor bolt, the market puts forward more stringent requirements for its corrosion resistance and tensile strength. Therefore, the development of a new type of anchor bolt has very important significance for practical engineering applications. SUMMARY

[0004] The present application provides a corrosion-resistant anchor bolt, which solves the problem of poor corrosion resistance and tensile strength of the anchor bolt in the related art.

[0005] The technical scheme of the present application is as follows:

[0006] The present application provides a corrosion-resistant anchor bolt, which is obtained by cold upsetting, thread processing and phosphating treatment of a blank, the blank is composed of the following components by weight percentage: C 0.33%-0.51%, Mn 0.4%-0.7%, Cr 1.3%-2.5%, Al 1.2%-4.8%, Zr 1.2%-4.9%, Nb 2.8%-4.8%, P≤0.015%, S≤0.01%, and the rest is Fe and other unavoidable impurities.

[0007] As a further technical scheme, during the phosphating treatment, the phosphating solution comprises the following components by weight: phosphoric acid 80-100 parts, zinc nitrate 40-60 parts, manganese nitrate 30-50 parts, zinc phosphate 30-50 parts, and water 1000 parts.

[0008] As a further technical scheme, the ratio of the sum of the weights of Al and Zr to the weight of Nb is 1≤(Al+Zr) / Nb≤2.

[0009] In the present application, when the ratio of the sum of the weights of Al and Zr to the weight of Nb is 1≤(Al+Zr) / Nb≤2, it helps to further improve the tensile strength of the anchor bolt.

[0010] As a further technical scheme, the weight of Al is greater than the weight of Zr.

[0011] In the application, when the ratio of the sum of the weight of Al and Zr to the weight of Nb is 1≤(Al+Zr) / Nb≤2 and the weight of Al is greater than the weight of Zr, the tensile strength of the anchor bolt is further improved.

[0012] As a further technical solution, during the phosphating process, the phosphating solution comprises the following components by weight: 80-100 parts of phosphoric acid, 40-60 parts of zinc nitrate, 30-50 parts of manganese nitrate, 30-50 parts of zinc dihydrogen phosphate, 5-9.5 parts of montmorillonite, and 1000 parts of water.

[0013] In the application, the phosphating process is carried out by using a composite phosphating system, which is beneficial to further improve the corrosion resistance of the anchor bolt. Among them, the montmorillonite in the phosphating solution can be adsorbed on the surface of the blank, promoting the formation of phosphate crystals; on the other hand, it can be filled in the pores of the phosphate film layer to form a more dense phosphating film, thereby further improving the corrosion resistance of the anchor bolt.

[0014] As a further technical solution, the particle size of the montmorillonite is 1000-2000 mesh.

[0015] As a further technical solution, the montmorillonite is modified montmorillonite, and the modified montmorillonite comprises the following components: montmorillonite, ferric ammonium citrate and copper chloride.

[0016] In the application, the montmorillonite is modified by using ferric ammonium citrate and copper chloride, which further improves the corrosion resistance of the anchor bolt. It is speculated that this is because the cation exchange capacity of the modified montmorillonite is further improved, thereby further promoting the formation of phosphate crystals and making the phosphating film more dense.

[0017] As a further technical solution, in the modified montmorillonite, the weight ratio of the montmorillonite to ferric ammonium citrate and copper chloride is 90:3-8:2.

[0018] In the application, when the weight ratio of the montmorillonite to ferric ammonium citrate and copper chloride in the modified montmorillonite is 90:3-8:2, the corrosion resistance of the anchor bolt is further improved.

[0019] As a further technical solution, the preparation method of the modified montmorillonite comprises the following steps: dispersing the montmorillonite in water, adjusting the pH value to 6-6.5, adding ferric ammonium citrate and copper chloride, mixing uniformly, reacting, filtering, and obtaining the modified montmorillonite.

[0020] As a further technical solution, during the reaction, the temperature is 60-80℃ and the time is 2-3h.

[0021] The application further provides a preparation method of the corrosion-resistant anchor bolt.

[0022] As a further technical scheme, the temperature is 40-50 DEG C and the time is 20-30 min during the phosphating treatment.

[0023] The application has the following working principles and advantages:

[0024] In the application, the synergistic effect of elements is fully exerted by optimizing the element composition of the anchor bolt blank, and the anchor bolt has good corrosion resistance and tensile strength after phosphating treatment, so that the need of practical engineering application can be met. Especially, the tensile strength of the anchor bolt is obviously improved by the combined action of Al, Zr and Nb. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments of the application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the application.

[0026] In the following examples and comparative examples, the blank is obtained by a conventional casting process, and the particle size of the montmorillonite is 1500 mesh, unless otherwise specified.

[0027] Example 1

[0028] The preparation method of the corrosion-resistant anchor bolt comprises the following steps: the blank is cold upset, threaded and phosphated to obtain the anchor bolt.

[0029] The blank is composed of the following components in percentage by weight: C 0.33%, Mn 0.4%, Cr 1.3%, Al 1.2%, Zr 1.2%, Nb 2.8%, P 0.015%, S 0.01%, and the rest is Fe and other inevitable impurities.

[0030] During the phosphating treatment, the temperature is 40 DEG C and the time is 30 min, and the phosphating solution comprises the following components in parts by weight: phosphoric acid 80 parts, zinc nitrate 40 parts, manganese nitrate 30 parts, zinc phosphate 30 parts and water 1000 parts.

[0031] Example 2

[0032] The preparation method of the corrosion-resistant anchor bolt comprises the following steps: the blank is cold upset, threaded and phosphated to obtain the anchor bolt.

[0033] The blank is composed of the following components in percentage by weight: C 0.51%, Mn 0.7%, Cr 2.5%, Al 4.8%, Zr 4.9%, Nb 4.8%, P 0.01%, S 0.005%, and the rest is Fe and other inevitable impurities;

[0034] The phosphating treatment is performed at a temperature of 50 DEG C for 20 minutes, and the phosphating solution comprises the following components in parts by weight: phosphoric acid 100 parts, zinc nitrate 60 parts, manganese nitrate 50 parts, zinc dihydrogen phosphate 50 parts, and water 1000 parts.

[0035] Example 3

[0036] The preparation method of the corrosion-resistant anchor bolt comprises the following steps: after the blank is subjected to cold upsetting, thread processing and phosphating treatment, the anchor bolt is obtained.

[0037] The blank is composed of the following components in percentage by weight: C 0.41%, Mn 0.55%, Cr 1.8%, Al 1.8%, Zr 2.4%, Nb 4.8%, P 0.015%, S 0.01%, and the rest is Fe and other inevitable impurities.

[0038] The phosphating treatment is performed at a temperature of 45 DEG C for 25 minutes, and the phosphating solution comprises the following components in parts by weight: phosphoric acid 80 parts, zinc nitrate 40 parts, manganese nitrate 30 parts, zinc dihydrogen phosphate 30 parts, and water 1000 parts.

[0039] Example 4

[0040] The difference between the present example and Example 3 is that, in the present example, the blank is composed of the following components in percentage by weight: C 0.41%, Mn 0.55%, Cr 1.8%, Al 2.7%, Zr 3.5%, Nb 2.8%, P 0.015%, S 0.01%, and the rest is Fe and other inevitable impurities.

[0041] Example 5

[0042] The difference between the present example and Example 3 is that, in the present example, the blank is composed of the following components in percentage by weight: C 0.41%, Mn 0.55%, Cr 1.8%, Al 2%, Zr 2.5%, Nb 4.5%, P 0.015%, S 0.01%, and the rest is Fe and other inevitable impurities.

[0043] Example 6

[0044] The difference between this embodiment and embodiment 3 is that in this embodiment, the blank is composed of the following components in percentage by weight: C 0.41%, Mn 0.55%, Cr 1.8%, Al 2%, Zr 4%, Nb 3%, P 0.015%, S 0.01%, and the rest is Fe and other inevitable impurities.

[0045] Embodiment 7

[0046] The difference between this embodiment and embodiment 6 is that in this embodiment, the percentage by weight of Al in the blank is 3%, and the percentage by weight of Zr in the blank is 3%.

[0047] Embodiment 8

[0048] The difference between this embodiment and embodiment 6 is that in this embodiment, the percentage by weight of Al in the blank is 4%, and the percentage by weight of Zr in the blank is 2%.

[0049] Embodiment 9

[0050] The difference between this embodiment and embodiment 3 is that in this embodiment, the phosphating solution comprises the following components in parts by weight: phosphoric acid 80 parts, zinc nitrate 40 parts, manganese nitrate 30 parts, zinc dihydrogen phosphate 30 parts, montmorillonite 5 parts, and water 1000 parts.

[0051] Embodiment 10

[0052] The difference between this embodiment and embodiment 3 is that in this embodiment, the phosphating solution comprises the following components in parts by weight: phosphoric acid 100 parts, zinc nitrate 60 parts, manganese nitrate 50 parts, zinc dihydrogen phosphate 50 parts, montmorillonite 9.5 parts, and water 1000 parts.

[0053] Embodiment 11

[0054] The difference between this embodiment and embodiment 10 is that in this embodiment, the montmorillonite is modified montmorillonite, and the preparation method of the modified montmorillonite comprises the following steps: dispersing 8.1 parts of montmorillonite in 100 parts of water, adjusting the pH value to 6.5, adding 1.4 parts of ferric ammonium citrate, mixing uniformly, reacting at 70°C for 2.5h, filtering, and obtaining the modified montmorillonite.

[0055] Embodiment 12

[0056] The difference between this embodiment and embodiment 11 is that in this embodiment, the preparation method of the modified montmorillonite comprises the following steps: dispersing 8.1 parts of montmorillonite in 100 parts of water, adjusting the pH value to 6.5, adding 1.4 parts of copper chloride, mixing uniformly, reacting at 70°C for 2.5h, filtering, and obtaining the modified montmorillonite.

[0057] Embodiment 13

[0058] The difference between this example and Example 11 is that in this example, the preparation method of the modified montmorillonite comprises the following steps: dispersing 8.1 parts of montmorillonite in 100 parts of water, adjusting the pH value to 6.5, adding 1.22 parts of iron ammonium citrate and 0.18 parts of copper chloride, mixing uniformly, reacting at 70°C for 2.5h, filtering, and obtaining the modified montmorillonite.

[0059] Example 14

[0060] The difference between this example and Example 11 is that in this example, the weight parts of montmorillonite is 9.24 parts, the weight parts of iron ammonium citrate is 0.05 parts, and the weight parts of copper chloride is 0.21 parts when preparing the modified montmorillonite.

[0061] Example 15

[0062] The difference between this example and Example 11 is that in this example, the weight parts of montmorillonite is 8.55 parts, the weight parts of iron ammonium citrate is 0.76 parts, and the weight parts of copper chloride is 0.19 parts when preparing the modified montmorillonite.

[0063] Example 16

[0064] The difference between this example and Example 11 is that in this example, the weight parts of montmorillonite is 9 parts, the weight parts of iron ammonium citrate is 0.3 parts, and the weight parts of copper chloride is 0.2 parts when preparing the modified montmorillonite.

[0065] Comparative Example 1

[0066] The difference between this comparative example and Example 1 is that in this comparative example, the blank is composed of the following components in weight percentage: C 0.33%, Mn 0.4%, Cr 1.3%, Al 2.4%, Nb 2.8%, P 0.015%, S 0.01%, and the rest is Fe and other unavoidable impurities.

[0067] Comparative Example 2

[0068] The difference between this comparative example and Example 1 is that in this comparative example, the blank is composed of the following components in weight percentage: C 0.33%, Mn 0.4%, Cr 1.3%, Zr 2.4%, Nb 2.8%, P 0.015%, S 0.01%, and the rest is Fe and other unavoidable impurities.

[0069] Comparative Example 3

[0070] The difference between the present comparative example and Example 1 is only that, in the present comparative example, the blank is composed of the following components in weight percentage: C 0.33%, Mn 0.4%, Cr 1.3%, Al 2.6%, Zr 2.6%, P 0.015%, S 0.01%, and the balance being Fe and other unavoidable impurities.

[0071] Comparative Example 4

[0072] The difference between the present comparative example and Example 1 is only that, in the present comparative example, the blank is composed of the following components in weight percentage: C 0.33%, Mn 0.4%, Cr 1.3%, Nb 5.2%, P 0.015%, S 0.01%, and the balance being Fe and other unavoidable impurities.

[0073] Experimental Example 1: Tensile Strength Test

[0074] The blanks in Examples 1-8 and Comparative Examples 1-4 were tested for tensile strength according to GB / T 228.1-2021 “Metallic Materials-Tensile Testing-Part 1: Method of Test at Room Temperature”, wherein the test rate was 0.005 s -1 . The test results are shown in Table 1 below.

[0075] Table 1: Tensile Strength Test Results

[0076]

[0077] Comparative Examples 1-4 and Example 1 show that, by optimizing the element composition of the anchor bolt blank to fully exert the synergistic effect between elements, especially through the combined action of Al, Zr and Nb, the tensile strength of the anchor bolt is significantly improved. Comparative Examples 3-4 and Examples 5-8 show that, when the ratio of the sum of the weights of Al and Zr to the weight of Nb is 1≤(Al+Zr) / Nb≤2, it helps to further improve the tensile strength of the anchor bolt. Comparative Examples 8 and Examples 6-7 show that, when the ratio of the sum of the weights of Al and Zr to the weight of Nb is 1≤(Al+Zr) / Nb≤2 and the weight of Al is greater than the weight of Zr, it helps to further improve the tensile strength of the anchor bolt.

[0078] Experimental Example 2: Corrosion Resistance Test

[0079] The anchor bolts prepared from Example 3 and Examples 9-16 were tested for corrosion resistance according to the neutral salt spray test method in GB / T 10125-2021 “Artificial Atmosphere Corrosion Test-Salt Spray Test”, and the time when corrosion first appeared was recorded, wherein the test temperature was 35°C, the concentration of sodium chloride solution was 50 g / L, and the pH value of the collected solution was 7. The test results are shown in Table 2 below.

[0080] Table 2 corrosion resistance test results

[0081]

[0082] The comparison between example 3 and example 9 shows that the corrosion resistance of the anchor bolt can be further improved by adding the montmorillonite into the phosphating solution to form a composite phosphating system. The comparison between example 10-12 and example 13 shows that the corrosion resistance of the anchor bolt can be further improved by modifying the montmorillonite with ferric ammonium citrate and copper chloride. The comparison between example 13-14 and example 15-16 shows that the corrosion resistance of the anchor bolt can be further improved when the weight ratio of the montmorillonite to ferric ammonium citrate and copper chloride in the modified montmorillonite is 90:3-8:2.

[0083] The above only describes preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A corrosion resistant anchor bolt obtained by cold heading, thread machining and phosphating treatment of a blank, characterized in that, The blank is composed of the following components in percentage by weight: C 0.33%-0.51%, Mn 0.4%-0.7%, Cr 1.3%-2.5%, Al 1.2%-4.8%, Zr 1.2%-4.9%, Nb 2.8%-4.8%, P≤0.015%, S≤0.01%, and the rest is Fe and other inevitable impurities; the ratio of the sum of the weight of Al and Zr to the weight of Nb is 1≤(Al+Zr) / Nb≤2; the weight of Al is greater than the weight of Zr; The phosphating treatment is carried out at a temperature of 40-50 DEG C for 20-30 min. The modified montmorillonite comprises the following components: montmorillonite, ferric ammonium citrate and cupric chloride, and the weight ratio of the montmorillonite to the ferric ammonium citrate and the cupric chloride is 90:3-8:

2.

2. The corrosion resistant anchor bolt of claim 1, wherein, The preparation method of the modified montmorillonite comprises the following steps: dispersing montmorillonite in water, adjusting the pH value to 6-6.5, adding ferric ammonium citrate and cupric chloride, mixing uniformly, reacting, filtering, and obtaining the modified montmorillonite.

3. The corrosion resistant anchor bolt of claim 2, wherein, The reaction is carried out at a temperature of 60-80 DEG C for 2-3 h.

4. The method of claim 1 to 3, wherein The method comprises the following steps: The blank is subjected to cold upsetting, thread processing and phosphating treatment to obtain the anchor bolt.

5. The method of claim 4, wherein the corrosion resistant anchor bolt is prepared by the steps of: The phosphating treatment is carried out at a temperature of 40-50 DEG C for 20-30 min.

Images