CN108395742B

CN108395742B - Closed-pore metal anticorrosive coating with normally distributed pore diameters, and preparation method and application thereof

Info

Publication number: CN108395742B
Application number: CN201810451919.0A
Authority: CN
Inventors: 闫东明; 刘毅; 黄之昊
Original assignee: Zhejiang University ZJU
Current assignee: Zhejiang University ZJU
Priority date: 2018-05-12
Filing date: 2018-05-12
Publication date: 2020-08-11
Anticipated expiration: 2038-05-12
Also published as: CN108395742A

Abstract

The invention discloses a closed hole type metal anticorrosive coating with normally distributed pore diameters, which is provided with closed holes and does not contain through holes, wherein the pore diameters of the closed holes are in accordance with the normal distribution:

Description

Closed-pore metal anticorrosive coating with normally distributed pore diameters, and preparation method and application thereof

Technical Field

The invention belongs to the metal material technology, and particularly relates to a closed pore type metal anticorrosive coating with normally distributed pore diameters, and a preparation method and application thereof.

Background

Reinforced concrete structures will still be one of the most common forms of construction for a considerable time in the future. However, the steel bars in the concrete structure are susceptible to corrosion damage for long-term exposure to sea water, sea wind, etc., i.e., in a highly corrosive (chloride ion-laden) humid environment. Particularly, the surface of the concrete in a splash area is continuously in a dry-wet cycle, and the salt concentration in the pores on the surface of the concrete is gradually increased in the dry-wet cycle. Under the action of concentration difference, salt further permeates into the inner surface of the concrete until the surface of the steel bar is corroded. And once broken, the repair can be difficult or even so severe that it is impossible to repair. Therefore, long-term corrosion of marine concrete structures is a current urgent problem.

At present, the metal coating technology is an effective and economic corrosion prevention method, wherein the ceramic coating technology has long research time and high technical maturity, and has the advantages of 1) zero VOC (volatile organic compound) emission and environmental protection compared with an organic coating; 2) the internal structure is compact, and the physical isolation is good. Has been widely applied to the field of corrosion protection of metal substrates. But because of crystal water, free water and gas in the coating are evaporated to naturally form holes, the holes are divided into through holes and closed holes, the through holes are communicated with each other, so that the outer surface of the coating is communicated with the surface of the base metal, and the closed holes are independent closed holes and are not communicated with the outside or other holes. The existence of the through holes can lead external corrosive substances to permeate into the coating and directly reach the surface of the steel bar, so that spot corrosion is formed on the local part of the steel bar, and the corrosion resistance of the coating is reduced. Chinese patent CN105670366A discloses a low porosity coating for steel bar corrosion protection and a coating method thereof, wherein the porosity of the coating is reduced but the coating still does not reach the state without through holes. Furthermore, a practical problem must be solved when applying the coating to the surface of the steel reinforcement: the ductility of the coating can meet the requirement of the telescopic deformation of the steel bar. Specifically, in actual construction steel bar application, the construction steel bar is deformed under stress, and the strain value is hundreds to thousands of micro-strains. The protective coating coated outside the steel bars inevitably deforms along with the steel bars. Once the steel bar is in use, the strain reaches the deformation limit too much, the coating is cracked, seawater (mixed with chloride ions for corroding the steel bar) contacts the surface of the steel bar along the cracks of the coating, and the corrosion resistance of the coating is greatly reduced. This requires that the coating be fairly ductile to maintain protection of the steel.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide a closed hole type metal anticorrosive coating with normally distributed pore diameters, which is suitable for the metal anticorrosive field in the corrosive environment, such as saline-alkali soil, underground pipelines, ocean platforms and the like. The coating has the characteristics of high ductility, good wear resistance, good corrosion resistance, capability of coordinately deforming with the steel bar and the like.

The invention is realized by the following technical scheme:

the first purpose of the invention is to provide a closed-cell metal anticorrosive coating with normally distributed pore diameters, wherein the coating comprises the following components in percentage by weight: 55-70 parts of silicon oxygen compound, 20-35 parts of thermal expansion coefficient regulator, 3-9 parts of binder, 3-9 parts of alumina gel precursor, 1-3 parts of catalyst and 1-2 parts of chelating agent. The alumina gel precursor is selected from any one or more of aluminum nitrate nonahydrate, aluminum chloride hexahydrate, aluminum isopropoxide and aluminum sec-butoxide.

The coating is provided with closed pores and does not contain through holes, the closed pores are independent closed pores and are not communicated with the outside or other pores, and the pore diameter of the closed pores conforms to normal distribution:

(x) represents the distribution of pore sizes of closed pores, without units; x represents the pore size of a closed cell in meters (m); the position parameter μ represents the average value of the aperture, ranging from 0.00003 to 0.00005 in meters (m); the scale parameter σ represents the amplitude of the pore size distribution, ranging from 0.000005 to 0.00001, unitless. I.e. the distribution of closed cell pore sizes follows a normal distribution.

Further, the silicon-oxygen compound is selected from one or more of quartz sand, diatomite, quartz, tridymite and cristobalite. And the silicon oxide compound needs to be ultrafine powder, and can be a 1000-2000 mesh sieve, and preferably a 1100-1400 mesh sieve.

Further, the thermal expansion coefficient regulator is selected from any one or more of sodium metasilicate, potassium metasilicate, lithium metasilicate, titanium dioxide, zirconium oxide, vanadium oxide and scandium oxide.

Further, the binder is selected from one or more of chromium monoxide, chromium sesquioxide, nickel monoxide, nickel sesquioxide, manganese monoxide, manganese dioxide, cobalt monoxide and cobalt sesquioxide.

Further, the catalyst is selected from one or more of propylene oxide, hydrochloric acid, sulfuric acid, ammonia water and sodium hydroxide.

Further, the chelating agent is selected from any one or more of glacial acetic acid, ethyl acetoacetate and acetylacetone.

Furthermore, when the corrosion-resistant steel bar is used for corrosion prevention of steel bars, the ductility is high, the ultimate tensile strain can reach 1000-2200 micro strain, and the corrosion resistance of metal can be remarkably improved by 10-12 times. The coating is of a closed-pore structure, so that the deformation range of the coating is large, and the coating cannot be pulled due to too high rigidity. Therefore, the ultimate tensile strain of the coating is slightly larger than that of the steel bar, and the coating can be stretched with the steel bar in a coordinated mode and has higher ductility.

Further, as any one of the preferred embodiments of the present invention, the method for preparing a metal anticorrosion coating according to the present invention comprises the following steps:

1) grinding for the first time: 55-70 parts of silicon oxide compound, 20-35 parts of thermal expansion coefficient regulator and adhesive

3-9 parts of a caking agent are ground into powder;

2) preparing a mixed material: adding 3-9 parts of alumina gel precursor, 1-3 parts of catalyst, 1-2 parts of chelating agent and water into the raw materials, and mixing and stirring to obtain a mixed material;

3) and (3) drying: drying the mixed material obtained in the step 2);

4) and (3) second grinding: grinding the mixed material obtained in the step 3) into powder again;

5) coating: coating the powder obtained in the step 4) on a base metal;

6) and (3) sintering: sintering the base metal coated with the powder obtained in the step 5) at a high temperature to obtain a hole

Closed hole type metal anticorrosive coating with normally distributed apertures and closed hole type metal anticorrosive coating with normally distributed apertures

Metal products with metal anticorrosive coatings.

The composition of the coating comprises by weight: 55-70 parts of silicon oxygen compound, 20-35 parts of thermal expansion coefficient regulator, 3-9 parts of binder, 3-9 parts of alumina gel precursor, 1-3 parts of catalyst and 1-2 parts of chelating agent. The alumina gel precursor is selected from any one or more of aluminum nitrate nonahydrate, aluminum chloride hexahydrate, aluminum isopropoxide and aluminum sec-butoxide;

the metal anticorrosive coating has a closed pore structure, the closed pores are independent closed pores and are not communicated with the outside or other pores, and the pore diameter of the closed pores conforms to normal distribution:

(x) represents the distribution of pore sizes of closed pores, without units; x represents the pore size of a closed cell in meters (m); the position parameter μ represents the average value of the aperture, ranging from 0.00003 to 0.00005 in meters (m); the scale parameter σ represents the amplitude of the pore size distribution, ranging from 0.000005 to 0.00001, without units.

When the coating has closed pores without through holes, the corrosion resistance of the coating is not reduced due to the through holes. Therefore, the corrosion resistance of the coating is improved by 10-12 times by the closed-pore coating. Meanwhile, the closed pores with normally distributed pore diameters exist in the coating, and the normally distributed pore diameters mean that the pore diameters of the closed pores accord with the pore diameter distribution under an ideal state, so that the deformation capacity of the coating under the stretching condition is improved, namely the ductility and ultimate tensile strain are improved, and the coating and the reinforcing steel bar have good cooperative deformation capacity. The closed-pore metal anticorrosive coating with normally distributed pore diameters can be formed only by mixing six materials of a silica compound, a thermal expansion coefficient regulator, a binder, an alumina gel precursor, a catalyst and a chelating agent according to a specific proportion and performing complex physical and chemical reactions such as adsorption, high-temperature reaction, hydrolysis, polycondensation, interfacial reaction and the like

The precursor of the alumina gel is subjected to two-step reaction of hydrolysis and polymerization under the action of a catalyst and a chelating agent, so that the gel containing the aluminum oxide functional group, which has large specific surface area and uniform particle size dispersion, is formed and attached to the surface of metal, and the coating has more closed pores. And because the drying temperature and time are controlled, the evaporation of the water inside is slow, so that the closed pore distribution in the final coating layer meets the normal distribution. Meanwhile, the ethyl acetoacetate is used as a chelating agent, so that the formation of alumina sol gel can be effectively promoted. Meanwhile, the nano alumina gel has higher activity and can react with a silicon oxide compound, a thermal expansion coefficient regulator and a binder to form amorphous aluminum silicate at an interface, so that the coating has higher mechanical strength, the binding force between the coating and metal can be further improved, and the corrosion resistance of the coating is improved.

Further, the coating method in the step 5) can adopt an electrostatic spraying method, wherein the electrostatic voltage is 30-90 kilovolts, the current is 20-80 microamperes, the gas output is 5-8 liters per minute, and the spraying distance is 20-50 centimeters;

further, the sintering parameters of step 6) are as follows: sintering at 560 ℃ and 600 ℃ for 10-20 minutes at a heating rate of 5-15 ℃ per minute.

Further, the silicon-oxygen compound is selected from one or more of quartz sand, diatomite, quartz, tridymite and cristobalite. The silicon oxygen compound is ultrafine powder, and the particle size of the powder is 1000-2000 meshes, preferably 1100-1400 meshes. The silica compound is a main matrix material of the coating, the superfine particle size of the silica compound is favorable for forming a closed pore structure, meanwhile, the surface of the silica compound is tightly adsorbed by alumina aerogel, a three-dimensional network structure is formed after reaction and sintering, and the network structure can obviously improve the density and the corrosion resistance of the coating.

Further, the CTE modifying agent is selected from any one or more of sodium metasilicate, potassium metasilicate, lithium metasilicate, titanium dioxide, zirconium oxide, vanadium oxide, and scandium oxide, the CTE of the silica compound in the original coating is about 8(× 10)^-6/° c), wherein the metasilicate and metal oxide species increase the CTE (coefficient of thermal expansion) of the coating upon sintering, avoiding expansion cracking of the coating due to stress inhomogeneity upon heating. Meanwhile, due to the combined action of the three components, the integrity of the coating can be ensured in the cooling process, and the coating cannot crack.

Further, the binder is selected from one or more of chromium monoxide, chromium sesquioxide, nickel monoxide, nickel sesquioxide, manganese monoxide, manganese dioxide, cobalt monoxide and cobalt sesquioxide. For example, when the binder is chromium oxide, in the high-temperature sintering process, oxygen in the chromium oxide is linked with aluminum in the coating to form an aluminum-oxygen bond, and the chromium is linked with the oxide layer on the metal surface to form a chromium-oxygen bond. Therefore, a strong chemical bond can be formed in the coating and the metal, and the close adhesion performance of the coating and the metal can be ensured.

Further, the catalyst is selected from any one or more of propylene oxide, hydrochloric acid, sulfuric acid, ammonia water and sodium hydroxide.

It is a third object of the present invention to provide a metal product comprising a closed pore type metal corrosion protection coating having normally distributed pore sizes in any of the forms as described above.

The fourth purpose of the invention is to provide the closed pore type metal anticorrosive coating with normally distributed pore diameters in any form and the application of the metal product, which can be applied to various fields such as civil construction, pipelines, underground pipe galleries, ocean oil production platforms, basic construction of saline-alkali soil, new energy power generation and the like.

Compared with the prior art, the invention has the following beneficial effects:

1) because the silicon oxide compound, the thermal expansion coefficient regulator, the binder, the alumina gel precursor, the catalyst and the chelating agent are added, the coating has a closed pore structure, and only closed pores do not have through holes, the pore size distribution meets the normal distribution:

the numerical meaning in the formula: (x) represents the distribution of pore sizes of closed pores, without units; x represents the pore size of a closed cell in meters (m); the position parameter μ represents the average value of the aperture, ranging from 0.00003 to 0.00005 in meters (m); the scale parameter σ represents the amplitude of the pore size distribution, ranging from 0.000005 to 0.00001, without units. I.e. the distribution of closed cell pore sizes follows a normal distribution. Because of the special characteristics of the material and the coating structure, the coating has high ductility, and the steel bar is a ductile materialWhen the steel bar for construction is in working state, the strain can reach 1500-2000 micro strain. The coating limit tensile strain of the invention reaches 1000-. Therefore, the coating can be stretched along with the construction steel bars in a coordinated mode, and the coating has extremely high ductility. 2) The coating disclosed by the invention has good corrosion resistance. The coating can improve the corrosion resistance of the steel bar by more than 10 times in a simulated seawater immersion environment.

Drawings

FIG. 1 is a partial electron micrograph (scale: 250 μm) of example 1.

Detailed Description

The following examples are intended to illustrate the invention only and are not intended to limit the scope of the invention. Further, it should be understood that various changes and modifications of the present invention may be made by those skilled in the art after reading the teachings of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.

Example 1:

1) grinding for the first time: grinding 62 parts of silicon-oxygen compound, 26 parts of thermal expansion coefficient regulator and 6 parts of binder into powder;

2) preparing a mixed material: adding 3 parts of alumina gel precursor, 2 parts of catalyst, 1 part of chelating agent and water into the raw materials, and mixing and stirring to obtain a mixed material;

3) and (3) drying: drying the mixed material obtained in the step 2);

5) coating: coating the powder obtained in the step 4) on a base metal,

6) and (3) sintering: sintering the base metal coated with the powder obtained in the step 5) at a high temperature to obtain the closed pore type metal anticorrosive coating with normally distributed pore diameters and the metal product with the closed pore type metal anticorrosive coating with normally distributed pore diameters.

Further, the coating method of step 5) may adopt an electrostatic spraying method, wherein the electrostatic voltage is 60 kv, the current is 50 microamperes, the gas output is 6.5 liters per minute, and the spraying distance is 35 cm;

further, the sintering parameters of step 6) are as follows: sintering at 580 deg.C for 20 min at a rate of 10 deg.C per minute.

The specific procedures of examples 1-3 and comparative examples 1-3 are as in example 1, and the specific compounding ratios (weight ratios) are shown in Table 1

TABLE 1 specific ingredient ratios (by weight) and fabrication Process parameter settings for examples 1-3 and comparative examples 1-3

The pore size of closed pores in the coating is counted through an SEM (scanning electron microscope), and the distribution condition of the pore size of the closed pores can be obtained through mathematical fitting, so that the position parameters and the scale parameters of normal distribution are obtained.

As can be seen from table 1, the closed pore type metal anticorrosive coating with normally distributed pore diameters according to the present invention can be prepared only when the silicon oxide compound, the thermal expansion coefficient modifier, the binder, the alumina gel precursor, the catalyst and the chelating agent satisfy specific mixture ratios and are combined with corresponding preparation processes.

In order to verify the effect of the coating layer and coating method for steel bar corrosion prevention of the present invention, experiments were performed:

1) abrasion resistance test

The coating according to the invention was produced on steel plates according to the coating process of example 1 and comparative example 1, respectively, with 2 replicates per test group, for a total of 4. The abrasion resistance of the coating was tested by referring to the shakeout erosion test method of ASTM D968-93, using sand that is the Chinese ISO standard sand. When a 2mm diameter area was flushed out of the surface of the coating, the shakeout was stopped and the volume of shakeout consumed was recorded. The larger the shakeout volume, the better the abrasion resistance of the coating.

Table 2 wear resistance test data

As can be seen from Table 2: shakeout volume numerically the coating of example 1 had a shakeout volume average of 12.8L, whereas the comparative example 1 had a shakeout volume average of 3.85L. The abrasion resistance of the coating of example 1 is much better than that of comparative example 1.

2) Corrosion resistance test of steel bars

Taking six groups of coated steel bars of examples 1-3 and comparative examples 1, 2 and 3, and one group of uncoated steel bars, respectively, the total number of the steel bars tested was 21. The test piece was placed in a 3.5% sodium chloride solution and subjected to an accelerated corrosion test after energization.

TABLE 3 accelerated Corrosion data of rebars

As can be seen from table 3, the coated steel bars of examples 1, 2,3 remained noncorrosive for 9-11 times the uncoated steel bars, and the coated steel bars of comparative examples 1, 2,3 remained noncorrosive for 5 times the uncoated steel bars, which was only one-half of the coated steel bars of examples 1, 2, 3.

3) Corrosion resistance test of steel plate

Taking six groups of coated steel bars of examples 1-3 and comparative examples 1, 2 and 3, and a group of uncoated steel plates, the total number of the steel plates tested is 21. The test piece was placed in a 3.5% sodium chloride solution and subjected to an accelerated corrosion test after energization.

TABLE 4 accelerated corrosion test of steel plates

As can be seen from Table 4, the coated steel sheets of examples 1, 2,3 remained non-corroded for 9-12 times as long as the non-coated steel sheets, and the coated steel sheets of comparative examples 1, 2,3 remained non-corroded for 5 times as long as the non-coated steel sheets, which was only one-half of those of examples 1, 2, 3.

4) Tensile test

The coated steel bars of examples 1 to 3 and comparative examples 1, 2 and 3 were taken, 3 replicates of each coated steel bar were obtained, and 3 resistance strain gauges were attached to each coated steel bar. When the experiment is started, the steel bar is placed on a tensile experiment machine, the change condition of the strain along with the load is measured, and the resistance strain gauge is connected with a strain gauge to measure the strain change on the coated steel bar.

TABLE 5 tensile test data

According to the experimental results of the above table 5, the average strain value of the coated steel bars in examples 1, 2 and 3 along with the tensile cracking of the steel bars is 1800-. The average strain value of the coated steel bars of comparative examples 1, 2 and 3 is in the range of 700 and 1000 microstrain, which indicates that the coated steel bars of comparative examples 1, 2 and 3 cannot be co-stretched with the construction steel bars. It is demonstrated that examples 1-3, which have a normal distribution of closed cell pore sizes, have a much greater ductility than comparative examples 1, 2,3, which do not have a normal distribution of closed cell pore sizes.

5) Electron micrograph of coating cross section

FIG. 1 is an electron micrograph of comparative example 1, which is similar to examples 2 and 3 and is therefore represented by 1. As can be seen from the figure, a transition layer exists between the coating and the surface of the steel bar, the transition layer fuses the steel bar and the inorganic coating, and the bonding capacity between the coating and the steel bar is enhanced. And the holes in the coating are all closed holes, and the closed hole distribution obtained by numerical calculation meets the normal distribution, namely meets the requirement of meeting the normal distribution

And the position parameter μ is 0.000046 (m); the scale parameter sigma is 0.000007, which is effective in improving the ductility of the coating.

Claims

1. A closed hole type metal anticorrosive coating with normally distributed pore diameters is characterized in that:

the composition of the coating comprises by weight: 55-70 parts of silicon-oxygen compound, 20-35 parts of thermal expansion coefficient regulator, 3-9 parts of binder, 3-9 parts of alumina gel precursor, 1-3 parts of catalyst and 1-2 parts of chelating agent; the alumina gel precursor is selected from any one or more of aluminum nitrate nonahydrate, aluminum chloride hexahydrate, aluminum isopropoxide and aluminum sec-butoxide;

the metal anti-corrosion coating has closed pores and does not contain through holes, and the pore diameter of the closed pores conforms to the normal distribution:

2. The closed pore type metal anticorrosive coating with normally distributed pore sizes according to claim 1, wherein the silica compound is selected from one or more of quartz sand, diatomite, quartz, tridymite and cristobalite.

3. The closed pore type metal anticorrosive coating with normally distributed pore diameters as claimed in claim 2, wherein the silica compound is ultrafine powder with a particle size of 1000-2000 mesh.

4. The closed pore type metal anticorrosive coating with normally distributed pore diameters as claimed in claim 2, wherein the silica compound is ultrafine powder, and the particle size of the powder is 1100-1400 mesh.

5. The closed-cell metal corrosion protection coating with normally distributed pore diameters as claimed in claim 1, wherein said thermal expansion coefficient modifier is selected from one or more of sodium metasilicate, potassium metasilicate, lithium metasilicate, titanium dioxide, zirconium oxide, vanadium oxide, and scandium oxide.

6. The closed-pore metal anticorrosive coating with normally distributed pore diameters of claim 1, wherein the binder is selected from one or more of chromium oxide, chromium sesquioxide, nickel oxide, nickel sesquioxide, manganese oxide, manganese dioxide, cobalt oxide and cobalt sesquioxide.

7. The closed pore type metal anticorrosive coating with normally distributed pore diameters of claim 1, wherein the catalyst is selected from one or more of propylene oxide, hydrochloric acid, sulfuric acid, ammonia water and sodium hydroxide.

8. The closed pore type metal anticorrosive coating with normally distributed pore diameters of claim 1, wherein the chelating agent is selected from one or more of glacial acetic acid, ethyl acetoacetate and acetylacetone.

9. The closed-cell metal corrosion-resistant coating with normally distributed pore diameters as claimed in any one of claims 1 to 8, wherein when the coating is used for steel bar corrosion protection, the ultimate tensile strain of the coating can reach 1000-2200 microstrain, and the corrosion resistance of the metal can be remarkably improved by 10-12 times.

10. A preparation method of a metal product with a metal anticorrosive coating is characterized by comprising the following steps:

1) grinding for the first time: grinding 55-70 parts of silicon-oxygen compound, 20-35 parts of thermal expansion coefficient regulator and 3-9 parts of binder into powder;

2) preparing a mixed material: adding 3-9 parts of alumina gel precursor, 1-3 parts of catalyst, 1-2 parts of chelating agent and water into the raw materials, and mixing and stirring to obtain a mixed material; the alumina gel precursor is selected from any one or more of aluminum nitrate nonahydrate, aluminum chloride hexahydrate, aluminum isopropoxide and aluminum sec-butoxide;

3) and (3) drying: drying the mixed material obtained in the step 2);

5) coating: coating the powder obtained in the step 4) on a base metal;

6) and (3) sintering: sintering the base metal coated with the powder obtained in the step 5) at a high temperature to obtain a closed pore type metal anticorrosive coating with normally distributed pore diameters and a metal product with the closed pore type metal anticorrosive coating with normally distributed pore diameters;

the coating has a closed pore structure, the closed pores are independent closed pores and are not communicated with the outside or other pores, and the pore diameter of the closed pores conforms to normal distribution:

11. The method according to claim 10, wherein the coating method of step 5) is an electrostatic spraying method in which the electrostatic voltage is 30 to 90 kv, the current is 20 to 80 microamperes, the gas discharge amount is 5 to 8 liters per minute, and the spraying distance is 20 to 50 cm.

12. The method according to claim 10, wherein the sintering parameters of step 6) are: sintering at 560 ℃ and 600 ℃ for 10-20 minutes at a heating rate of 5-15 ℃ per minute.

13. The method according to any one of claims 10 to 12, wherein the silica compound is selected from any one or more of quartz sand, diatomaceous earth, quartz, tridymite, and cristobalite.

14. The method as claimed in any one of claims 10 to 12, wherein the silica compound is a superfine powder having a particle size of 1000-2000.

15. The method as claimed in any one of claims 10 to 12, wherein the silica compound is a superfine powder having a particle size of 1100-1400 mesh.

16. The method according to any one of claims 10 to 12, wherein the thermal expansion coefficient adjuster is selected from any one or more of sodium metasilicate, potassium metasilicate, lithium metasilicate, titanium dioxide, zirconium oxide, vanadium oxide, and scandium oxide.

17. The method according to any one of claims 10 to 12, wherein the binder is selected from any one or more of chromium monoxide, chromium oxide, nickel monoxide, nickel oxide, manganese monoxide, manganese dioxide, cobalt monoxide, and cobalt oxide.

18. The method according to any one of claims 10 to 12, wherein the catalyst is selected from any one or more of propylene oxide, hydrochloric acid, sulfuric acid, aqueous ammonia, and sodium hydroxide.

19. The method according to any one of claims 10 to 12, wherein the chelating agent is selected from any one or more of glacial acetic acid, ethyl acetoacetate, and acetylacetone.

20. A metal product comprising a closed pore type metal corrosion protection coating having normally distributed pore sizes according to any one of claims 1 to 9.

21. The use of the closed pore type metal anticorrosive coating with normally distributed pore diameters as claimed in any one of claims 1 to 9 and the use of the metal product as claimed in claim 20 in the fields of pipelines, underground pipe galleries, ocean oil production platforms, saline-alkali land infrastructure and new energy power generation.