阅读说明：本技术 一种附属钢及其制备方法 (Auxiliary steel and preparation method thereof ) 是由 乐林江 沈伟 乐政 于 2021-08-31 设计创作，主要内容包括：本申请提供一种附属钢及其制备方法,该附属钢包括基材和合金层,所述合金层为将粉末渗剂渗入所述基材表面形成含有多元素的合金层；所述合金层中的组分以及各种组分的含量为：锌50wt％～75wt％、铝10wt％～20wt％、镁3wt％～10wt％、锰0.15wt％～1.5wt％,余量为所述基材中的组分。对于本申请中所保护的附属钢,当合金层中的锌、铝、镁、锰为权1所述的比例时,且合金层大于20μm时,其硬度、抗盐雾能力等均最佳,综合性能高,大大提升了附属钢的使用寿命,且其制备方法简单,成本低廉,具有较大应用和推广。(The application provides accessory steel and a preparation method thereof, the accessory steel comprises a substrate and an alloy layer, wherein the alloy layer is formed by infiltrating a powder infiltration agent into the surface of the substrate; the components in the alloy layer and the contents of various components are as follows: 50-75 wt% of zinc, 10-20 wt% of aluminum, 3-10 wt% of magnesium, 0.15-1.5 wt% of manganese and the balance of the components in the base material. For the auxiliary steel protected in the application, when zinc, aluminum, magnesium and manganese in the alloy layer are in the proportion stated in claim 1 and the alloy layer is larger than 20 microns, the hardness, the salt spray resistance and the like of the auxiliary steel are all the best, the comprehensive performance is high, the service life of the auxiliary steel is greatly prolonged, and the preparation method is simple, low in cost and has great application and popularization.)

1. The auxiliary steel comprises a base material and an alloy layer, wherein the alloy layer is formed by infiltrating a powder infiltration agent into the surface of the base material and contains a plurality of metal elements; the method is characterized in that:

the components in the alloy layer and the contents of various components are as follows: 50-75 wt% of zinc, 10-20 wt% of aluminum, 3-10 wt% of magnesium, 0.15-1.5 wt% of manganese and the balance of the components in the base material.

2. The satellite steel of claim 1, wherein the alloy layer has a thickness of 20 to 80 μ ι η;

preferably, the balance contains iron, and the content of iron is not less than 8%.

3. The satellite steel of claim 1, wherein the manganese content in the alloy layer is 5% to 10% of the magnesium content.

4. The auxiliary steel according to claim 1, wherein the powder infiltration agent is a multi-element powder infiltration agent, and the components and the parts by weight of the components comprise: 55-80 parts of zinc powder, 10-25 parts of zinc-aluminum alloy powder, 8-25 parts of aluminum-magnesium alloy powder, 0.1-1 part of rare earth oxide and 1-5 parts of an activating agent, wherein the activating agent contains Mn.

5. The accessory steel of claim 4, wherein the activator is ammonium chloride and potassium permanganate, wherein the potassium permanganate accounts for 5-20 wt%, and the balance is ammonium chloride.

6. The auxiliary steel according to claim 4, wherein the powder impregnation agent further comprises a dispersant and a catalyst, wherein the powder impregnation agent comprises 20 to 60 parts by weight of the dispersant and 0.5 to 2 parts by weight of the catalyst.

7. The satellite steel of claim 6, wherein the dispersant is at least one of alumina, silica, magnesia, aluminum nitride, silicon nitride, and silicon carbide;

the rare earth oxide comprises cerium oxide and/or lanthanum oxide;

the catalyst is manganese dioxide.

8. The incidental steel of claim 5, wherein in said zinc-aluminum alloy powder, the aluminum content is 5 to 40 wt%, the balance being zinc;

in the aluminum-magnesium alloy powder, the aluminum content is 30-60 wt%, and the balance is magnesium.

9. A method for producing a satellite steel according to any one of claims 1-8, characterized in that it is:

step 1: adopting a co-infiltration process, rotating the powder infiltration agent and the matrix together in a co-infiltration device so as to uniformly mix the infiltration agent;

step 2: heating the co-cementation device to a preset temperature, and then preserving heat for 1-10 hours to finish the zinc cementation;

preferably, the co-permeation device is vacuumized to enable the vacuum degree to be less than 100Pa, and then temperature rise treatment is carried out; more preferably, the reaction temperature in Step2 is between 400 ℃ and 450 ℃, and the reaction time is more than 1 hour.

10. The method for preparing the accessory steel according to claim 1, wherein Step2 comprises the following steps:

firstly, vacuumizing a co-permeation device to enable the vacuum degree of the co-permeation device to be less than 100Pa, and maintaining the vacuum degree in the reaction process;

secondly, raising the temperature in the co-permeation device to be within the range of 100-200 ℃, and staying for 1-3 hours;

thirdly, raising the temperature to 400-450 ℃ and reacting for 1-9 hours to finish the zinc impregnation.

Technical Field

The application relates to the field of chemistry, in particular to the related technical field of accessory steel surface treatment and the like, and particularly relates to accessory steel and a preparation method thereof.

Background

The railway bridge is a road section which is easy to damage in the whole railway system, and the service environment of the railway bridge has the comprehensive factors of high humidity, high wind speed, frequent vibration and the like. The auxiliary steel structure in the railway bridge is of great importance, and a plurality of events caused by the safety problem of the railway bridge caused by the corrosion of the auxiliary steel structure of the bridge occur every year.

The attached steel construction of railway bridge mainly includes: the support is embedded with plates, T-shaped steel, embedded sleeves, hanging baskets, fences and the like. The material is mainly Q235 and Q345.

At present, the method for the anticorrosion treatment of the auxiliary steel structure of the railway bridge mainly comprises powder zinc impregnation and closed passivation treatment, and the closed passivation layer is easy to fall off under the comprehensive factors of alternating load, wind sand, acid rain, ultraviolet light and the like, so that the actual service life of the auxiliary steel structure of the railway bridge is difficult to reach the design life. Therefore, a high-corrosion-resistance and high-wear-resistance steel structure product attached to the railway bridge needs to be developed to better meet the use requirement of a railway system. In the field, the related researches are mature, and the purpose of overcoming various obstacles in the prior art is more challenging.

Disclosure of Invention

In view of this, the embodiments of the present application provide an auxiliary steel and a method for manufacturing the same, so as to solve the technical defects in the prior art.

The invention of the application is to provide a subsidiary steel, which comprises a substrate and an alloy layer, wherein the alloy layer is formed by infiltrating a powder infiltration agent into the surface of the substrate to form an alloy layer containing multiple elements;

the components in the alloy layer and the contents of various components are as follows: 50-75 wt% of zinc, 10-20 wt% of aluminum, 3-10 wt% of magnesium, 0.15-1.5 wt% of manganese and the balance of the components in the base material.

Further, the thickness of the alloy layer is greater than 20 μm, such as 20 μm to 80 μm.

Further, the balance contains iron, and the content of the iron is not less than 8%.

Further, in the alloy layer, the content of manganese is 5% to 10%, preferably 6% to 8%, of the content of magnesium.

Further, the powder penetrant is a multi-element powder penetrant, and comprises the following components in parts by weight: 55-80 parts of zinc powder, 10-25 parts of zinc-aluminum alloy powder, 8-25 parts of aluminum-magnesium alloy powder, 0.1-1 part of rare earth oxide and 1-5 parts of an activating agent, wherein the activating agent contains Mn. Preferably 60-73 parts of zinc powder, 15-20 parts of zinc-aluminum alloy powder, 15-20 parts of aluminum-magnesium alloy powder, 0.4-0.7 part of rare earth oxide and 2-4 parts of activating agent.

Further, the activating agent is ammonium chloride and potassium permanganate, wherein in the activating agent, the proportion of the potassium permanganate is 5 wt% -20 wt%, and the balance is ammonium chloride.

Further, the powder impregnation agent also comprises a catalyst and a dispersing agent, wherein the weight part of the catalyst in the powder impregnation agent is 0.5-2 parts, preferably 0.6-1.2 parts.

The weight portion of the dispersing agent is 20-60 parts, preferably 25-35 parts.

Further, the dispersant is at least one of alumina, silica, magnesia, aluminum nitride, silicon nitride and silicon carbide.

Further, the catalyst is manganese dioxide.

Further, the rare earth oxide includes cerium oxide and/or lanthanum oxide.

Furthermore, in the zinc-aluminum alloy powder, the aluminum content is 5 wt% -40 wt%, and the balance is zinc.

Further, in the aluminum magnesium alloy powder, the aluminum content is 30 wt% -60 wt%, and the balance is magnesium.

Another aspect of the invention is to provide a method for producing the secondary steel according to any one of the above paragraphs, the method comprising:

step 1: adopting a co-infiltration process, rotating the powder infiltration agent and the matrix together in a co-infiltration device so as to uniformly mix the infiltration agent;

step 2: heating the co-cementation device to a preset temperature, and then preserving heat for 1-10 hours to finish the zinc cementation;

preferably, the co-permeation device is vacuumized to enable the vacuum degree to be less than 100Pa, and then temperature rise treatment is carried out; more preferably, the reaction temperature in Step2 is between 400 ℃ and 450 ℃, and the reaction time is more than 1 hour.

Further, at Step2,

firstly, vacuumizing a co-permeation device to enable the vacuum degree of the co-permeation device to be less than 100 Pa;

secondly, the temperature in the co-permeation device is raised to be within the range of 100 ℃ to 200 ℃, and the retention time is longer than 1 hour, such as 1 hour to 3 hours. Ensure that the ammonium chloride can be fully decomposed under the temperature condition and the potassium permanganate is not decomposed. The following reaction then takes place: 2KMnO₄+16HCl＝2KCl+2MnCl₂+5Cl₂↑+8H₂O；

Thirdly, raising the temperature to 400-450 ℃ and reacting for 1-9 hours to finish the zinc impregnation.

The invention has the beneficial effects that:

the method breaks through the obstacles in the prior art, improves the suitability of the surface layer of the accessory steel, the powder penetrating agent, the preparation method and the like, ensures that the obtained accessory steel has excellent performance and good appearance visual effect, can ensure that the alloy layer does not fall off under the conditions of alternating load, sand wind, acid rain, ultraviolet and the like, and has long service life. Has great application and popularization prospect. Specifically, the method comprises the following steps:

for the auxiliary steel protected in the application, when the zinc, the aluminum, the magnesium and the manganese in the alloy layer are in the proportion stated in the claim 1 and the alloy layer is larger than 20 micrometers, the hardness, the brittleness, the plasticity, the salt spray resistance and the like of the auxiliary steel are all the best, namely the comprehensive performance is high, and the service life of the auxiliary steel is greatly prolonged.

The multi-element penetrating agent for preparing the auxiliary steel alloy layer in the application can be subjected to co-penetration with an auxiliary steel matrix to obtain the auxiliary steel in the application by selecting the components of the multi-element penetrating agent and the content of each component, the content of each metal element in the auxiliary steel is gradually reduced from a surface layer to a deep layer, no deposition phenomenon exists, the penetration depth is deep, the falling-off phenomenon cannot occur, the hardness can reach about HV430-440, and the auxiliary steel can resist a neutral salt spray test for 3500 hours after sand blowing. And the proportion of the components in the penetrant not only can prepare the accessory steel, but also has no waste phenomenon and can realize synchronous penetration, so the penetrant has good effect and low comprehensive cost.

The preparation method is designed aiming at the type of the penetrating agent and the action of each component in the penetrating agent, and can assist the penetrating agent to enter an accessory steel matrix efficiently and orderly to obtain the alloy layer. The preparation method is low in temperature and can be completed only by 400-450 ℃, the defect that the mechanical property of the auxiliary steel is easy to deteriorate due to too high temperature is avoided, and the method is simple to operate, low in cost and high in economic benefit.

In conclusion, the auxiliary steel in the application can be applied to complex or harsh environments, is long in service life, low in cost, easy to popularize and use and has excellent application prospects.

Drawings

FIG. 1 is a schematic view of the appearance of satellite steels treated with an infiltrant according to an embodiment of the present application; wherein, fig. 1A is a schematic view of a hanging surrounding basket in a high-speed rail pier inspection facility, fig. 1B is a schematic view of an inspection ladder, and fig. 1C is a schematic view of a steel beam in attached steel.

FIG. 2 is a schematic cross-sectional view of the secondary steel after infiltration according to the example of the present application.

FIG. 3 is a photograph of a cross section of the satellite steel salt spray of the present application after 3000 hours.

Detailed Description

The following description of specific embodiments of the present application refers to the accompanying drawings.

In the present invention, unless otherwise specified, scientific and technical terms used herein have the meanings that are commonly understood by those skilled in the art. Also, the reagents, materials and procedures used herein are those that are widely used in the corresponding fields.

Example 1

This example provides a secondary steel comprising a substrate and an alloy layer, the alloy layer being formed by infiltrating a powdered infiltrant into a surface of the substrate to form an alloy layer containing multiple elements.

The components in the alloy layer and the contents of various components are as follows: 50 to 75 weight percent of zinc, 10 to 20 weight percent of aluminum, 3 to 10 weight percent of magnesium, 0.15 to 1.5 weight percent of manganese, and the balance 5 to 36.75 weight percent, and the balance being components of the substrate, such as iron, nickel, and other alloy elements if the substrate is composed of iron, nickel, and other alloy elements, iron, nickel, and other alloy elements if the substrate is composed of only iron and nickel, and iron, nickel, and the balance iron if the substrate is composed of only iron, and the balance iron, and the like.

Preferably, the contents of the components and the various components in the alloy layer are: 60-70 wt% of zinc, 14-18 wt% of aluminum, 5-8 wt% of magnesium, 0.4-0.64 wt% of manganese and the balance of components in the base material, wherein the amount of the components in the base material is generally 10-20 wt%, wherein the components infiltrated into the alloy layer are aluminum, magnesium, zinc and manganese, for example, the content of the infiltrated components in the alloy layer can be any one of the following groups: 60 wt% of zinc, 18 wt% of aluminum, 5 wt% of magnesium and 0.64 wt% of manganese; 70 wt% of zinc, 14 wt% of aluminum, 8 wt% of magnesium and 0.4 wt% of manganese; ③ 65 percent of zinc, 16 percent of aluminum, 6 percent of magnesium and 0.48 percent of manganese; 70 wt% of zinc, 16 wt% of aluminum, 7 wt% of magnesium and 0.55 wt% of manganese.

The alloy layer has a thickness of more than 20 μm, such as 20 μm to 80 μm, specifically, such as 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, etc. In the system of the present application, the thickness of the alloy layer is generally between 50 and 75 μm, such as 53 μm, 58 μm, 62 μm, 67 μm, etc., which is far beyond the level of the prior art. The uniform and deep immersion of the powder makes the overall properties of corrosion resistance, wear resistance, plasticity, rigidity, etc. of the accessory steel more superior, thereby enabling the accessory steel to be used in environments such as railways where the requirements for the accessory steel are high.

Preferably, the balance contains iron, and the content of iron is not less than 8%. In practice, the secondary steel is generally of steel structure with iron as the main component, and therefore, the iron content is generally more than 10%. In the system of the application, manganese in the alloy layer can form a composite system with iron, so that the harmful effect of the iron can be reduced, and the wear resistance and the corrosion resistance of the iron are improved.

In a further preferred embodiment, the manganese content in the alloy layer is 5% to 10%, preferably 6% to 8%, such as 5%, 6%, 7%, 8%, 9%, 10% of the magnesium content. During infiltration of the powder into the accompanying steel, the infiltrated layer or accompanying steel will have a certain amount of iron, which, as mentioned above, is an important factor in the corrosion resistance of the high magnesium content structure of the surface layer. The addition of manganese can greatly reduce the deleterious effects of iron in the infiltrated layer. Manganese is added into the infiltrated layer, mainly for improving the corrosion resistance and the wear resistance of the infiltrated layer surface layer. When the magnesium contains 1-15% of manganese, the corrosion resistance of the surface layer can be greatly improved, the defects caused by high local magnesium content are avoided, and a complex with better performance can be generated with the magnesium. In particular, because excessive magnesium is easily enriched in the outermost layer of the zinc-magnesium-aluminum infiltrated layer, the excessive magnesium causes the surface layer of the infiltrated layer tissue to be rapidly corroded in the corrosion process. Manganese is added into the infiltrated layer structure, and the purpose is mainly to improve the corrosion resistance of the infiltrated layer surface layer. If too much manganese is present, it may reduce the plasticity of the alloy layer, and therefore, in the system of the present application, this content is suitable to balance the other metal components and also to increase the overall effect of the secondary steel.

In the present embodiment, it is shown through a large number of experimental data that when the alloy layer contains the above-described specific amounts of the alloy components and the alloy layer is larger than 20 μm, the hardness, brittleness, plasticity, salt spray resistance, and the like are optimized. Namely, when the metal alloy layer on the surface of the accessory steel contains zinc, aluminum, magnesium and manganese with specific contents, the corrosion resistance and the wear resistance of the accessory steel are greatly improved, and the service life is greatly prolonged.

Example 2

Based on example 1, it is found that the alloy layer of the accompanying steel of the present invention containing zinc, aluminum, magnesium, and manganese in specific contents is excellent in combination of corrosion resistance and wear resistance. The accompanying steel of the examples can be obtained by making these components in the alloy layer in these contents, mainly by using the following multi-component powder impregnation agent.

The multi-element powder penetrant comprises the following components in parts by weight: 55-80 parts of zinc powder, 10-25 parts of zinc-aluminum alloy powder, 8-25 parts of aluminum-magnesium alloy powder, 0.1-1 part of rare earth oxide and 1-5 parts of an activating agent, wherein the activating agent contains Mn. Preferably, the zinc powder is 60-73 parts, the zinc-aluminum alloy powder is 15-20 parts, the aluminum-magnesium alloy powder is 15-20 parts, the rare earth oxide is 0.4-0.7 part, and the activating agent is 2-4 parts. For example, the components of the multi-element powder penetration agent can be any one of the following groups: 60 parts of zinc powder, 20 parts of zinc-aluminum alloy powder, 15 parts of aluminum-magnesium alloy powder, 0.7 part of rare earth oxide and 2 parts of activator; 73 parts of zinc powder, 15 parts of zinc-aluminum alloy powder, 20 parts of aluminum-magnesium alloy powder, 0.4 part of rare earth oxide and 4 parts of activator; 65 parts of zinc powder, 18 parts of zinc-aluminum alloy powder, 16 parts of aluminum-magnesium alloy powder, 0.5 part of rare earth oxide and 3 parts of activator; 70 parts of zinc powder, 16 parts of zinc-aluminum alloy powder, 18 parts of aluminum-magnesium alloy powder, 0.6 part of rare earth oxide and 4 parts of activator.

The activating agent is ammonium chloride and potassium permanganate, and in the activating agent, the proportion of the potassium permanganate is 5 wt% -20 wt%, preferably 10-18 wt%, such as 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 18 wt% and the like, and the balance is ammonium chloride. The potassium permanganate starts to decompose at about 220 ℃ to 350 ℃, the decomposition starting temperature of the ammonium chloride is 100 ℃, and the ammonium chloride can react with the potassium permanganate at 100-200 ℃ to generate substances capable of permeating manganese and catalyzing other components to permeate or react. While other ammonium halides are not preferred because the hydrogen fluoride from the decomposition of ammonium fluoride does not react with potassium permanganate, ammonium bromide, ammonium iodide, ammonium fluoride are not used because the decomposition temperature is higher than that of potassium permanganate.

In a further preferred embodiment, the powder impregnation agent further comprises a catalyst and/or a dispersant, wherein the catalyst is present in the powder impregnation agent in an amount of 0.5 to 2 parts by weight, preferably 0.6 to 1.2 parts by weight, such as 0.6 part, 0.7 part, 0.8 part, 0.9 part, 1.0 part, 1.1 part, and 1.2 parts by weight.

In a further preferred embodiment, the catalyst is manganese dioxide, which contributes to the penetration of manganese after the reaction with potassium permanganate and also reacts with ammonium chloride to promote the diffusion of magnesium, aluminum and zinc into the infiltrated layer, but manganese dioxide itself does not contribute to the inclusion of manganese in the alloy layer.

In a more preferred embodiment, the dispersant is present in an amount of 20 to 60 parts by weight. Preferably 25-35 parts of dispersant, such as 25 parts, 28 parts, 30 parts, 32 parts and 35 parts.

Preferably, the dispersant is preferably at least one of alumina, silica, magnesia, aluminum nitride, silicon nitride, and silicon carbide. These dispersants are effective in preventing the metal powder from binding in the system of the present invention.

As a further preferred embodiment, the rare earth oxide is a nano rare earth oxide comprising cerium oxide and/or lanthanum oxide. The rare earth oxide has the function of promoting infiltration.

In a further preferred embodiment, the zinc-aluminum alloy powder contains 5 to 40 wt%, preferably 15 to 30 wt% of aluminum, and the balance being zinc, and the aluminum content may be 15, 18, 20, 22, 25, 28, 30 wt%, or the like. The use of the zinc-aluminum alloy powder promotes a certain amount of aluminum to be synchronously infiltrated in the process of zinc infiltration; if the aluminum content in the zinc-aluminum alloy powder is too high, the aluminum co-penetration effect is poor, and therefore, the ratio is optimal. Moreover, if a certain amount of aluminum is simultaneously infiltrated into the infiltrated layer, the aluminum and the iron in the matrix can form an iron-aluminum intermetallic compound phase, which has a significant effect on improving the wear resistance of the infiltrated layer as a whole.

In the aluminum-magnesium alloy powder, the aluminum content is 30 wt% -60 wt%, and the balance is magnesium, for example, the aluminum content can be 30 wt%, 40 wt%, 45 wt%, 50 wt%, 55 wt%, 60 wt%, and the like. The two are eutectic alloys, and the mass ratio of the two is in the above proportion, the melting point of the alloy is just about 450 ℃, which is far lower than the melting points of simple substance magnesium and aluminum, and the simple substance magnesium and aluminum are both higher than 650 ℃, therefore, the powder zinc impregnation process is more beneficial to promoting the synchronous infiltration of magnesium and aluminum, and compared with other proportions, the infiltration uniformity and amount are better, and therefore, the comprehensive effect is better. In addition, the magnesium and the aluminum form alloy powder, so that the defects that the magnesium powder is easy to explode and oxidize and is low in content, and the magnesium powder is difficult to continuously permeate to form local parts and even cause the reduction of metal performance are avoided. Moreover, in the system of the present application, the magnesium content in the aluminum magnesium alloy powder is generally not more than 70 wt%, and since excess magnesium is easily concentrated in the outermost layer of the carburized layer in the zinc-magnesium carburized layer, the excess magnesium causes relatively poor corrosion resistance and wear resistance of the carburized layer surface layer.

In the embodiment, the multi-element powder infiltration agent contains pure zinc powder, which can be normally infiltrated in the process of the application; the aluminum-magnesium alloy powder simultaneously contains two alloy powders of zinc-aluminum alloy powder and aluminum-magnesium alloy powder, wherein the zinc-aluminum alloy powder enables a certain amount of aluminum to be synchronously infiltrated when the infiltrated zinc passes through. The aluminum-magnesium alloy powder is eutectic alloy, and the melting point of the aluminum-magnesium alloy powder are low in the proportion given by the application, so that the system and the infiltration method are more favorable for promoting the simultaneous infiltration of magnesium and aluminum while zinc infiltration is carried out. The multielement powder penetrating agent also contains an activating agent, wherein the activating agent contains more ammonium chloride, can decompose and provide ammonia and hydrogen halide gas, can play a role in cleaning the surface of the metal piece once, and can also play a role in activating other components so as to promote the zinc penetration. Meanwhile, the hydrogen halide can react with potassium permanganate, the generated manganese chloride can be used as a manganese source to enable manganese to enter a permeable layer, the manganese chloride also has a certain effect of promoting metal permeation, and more importantly, chloride ions in the active manganese chloride also contribute to promoting manganese permeation into permeable layer tissues. The reaction of potassium permanganate and hydrogen chloride can provide manganese chloride as manganese permeating agent and produce potassium chloride as excellent catalyst for permeating various metals. Pure manganese metal cannot permeate, manganese chloride is basically hydrated manganese chloride and cannot be used, and potassium chloride is not preferable because the manganese chloride is also hydrated potassium chloride. In addition, the effect of rare earth oxide, dispersing agent and the like in the application is matched, so that aluminum, magnesium and manganese are synchronously infiltrated in the process of zinc infiltration. The metal element is not easy to enrich on the surface layer to influence the performance if the metal element is infiltrated synchronously as much as possible, and the system can enable the thickness of an infiltrated layer to reach 20-100 mu m while infiltrating synchronously, so that the metal can realize excellent corrosion resistance and wear resistance. More importantly, the system of the present application also enables the zinc and magnesium to act in the percolated layer, thereby increasing its corrosion resistance. Specifically, the atomic radius of zinc is 0.1332 nm, the atomic radius of magnesium is 0.1598 nm, the difference between the atomic radii is less than 15%, and the magnesium and the zinc are simultaneouslyBoth are in a hexagonal close-packed structure, so that the two can jointly act to form a permeable layer. Although magnesium is not corrosion resistant by itself, it can occupy some of the zinc atom sites in the zinc crystal structure, particularly at the grain boundaries, and some amount of magnesium can accumulate at the zinc weak grain boundaries and form MgZn by high temperature reaction₂、Mg₂Zn₁₁Equal zinc-magnesium alloy phase, MgZn₂、Mg₂Zn₁₁The alloy phase itself is a high corrosion resistant phase, and the original weak grain boundary structure can be promoted to be changed into a strong grain boundary structure formed at the grain boundary, particularly, the strong grain boundary structure is opaque to corrosive substances such as chloride ions, and the corrosive substances can be blocked outside. At the same time, MgZn₂、Mg₂Zn₁₁In the corrosion process of the zinc-magnesium alloy phase, a corrosion product is changed from a loose structure of common powder zinc impregnation into a compact structure, so that the corrosion resistance of the metal piece is greatly improved, and the service life of the metal piece is greatly prolonged.

In summary, the accessory steel provided in this embodiment is a schematic diagram of different types of accessory steels treated by the penetrating agent of the present application, as shown in fig. 1, in which fig. 1A is a surrounding basket as a high-speed railway pier inspection facility, fig. 1B is an inspection ladder, and fig. 1C is a schematic diagram of a steel beam in the accessory steel. The treated auxiliary steel has good comprehensive performance, and the multi-element powder penetrating agent can realize that the alloy layer of the auxiliary steel product contains aluminum, magnesium, zinc and manganese with specific content, so that the penetrating agent is complementary with the auxiliary steel product to comprehensively realize excellent corrosion resistance and wear resistance.

Example 3

On the basis of the embodiment 1 and/or the embodiment 2, the embodiment discloses a preparation method of the accessory steel, which comprises the following steps:

step 1: a rotary furnace body co-infiltration process is adopted, the powder infiltration agent and the matrix rotate together in the multi-element alloy co-infiltration furnace, so that the uniform mixing of the infiltration agent is ensured, and the uniform reaction can be ensured; the mixing uniformity and the reaction uniformity can be realized by the conventional technology in the field at present, and the method is very basic condition guarantee.

Step 2: heating the co-cementation device to a preset temperature, and then preserving heat for 1-10 hours (usually 4-7 hours) to finish the zinc cementation;

preferably, the co-infiltration furnace is evacuated to a vacuum degree of less than 100Pa, and then subjected to a temperature raising treatment, wherein the vacuum degree is maintained throughout the reaction. The reaction temperature in Step2 is 400-450 ℃, and the reaction time is more than 1 hour.

In a further preferred embodiment, in Step2,

firstly, vacuumizing the co-permeation furnace to enable the vacuum degree of the co-permeation furnace to be less than 100Pa, then heating, and maintaining the vacuum degree of the co-permeation furnace to be less than 100Pa through vacuumizing so as to quickly pump away the generated chlorine and water vapor. Prevent the steam from influencing the powder infiltration and prevent the chlorine from causing potential safety hazard.

Secondly, the temperature in the co-cementation furnace is raised to be within the range of 100 ℃ to 200 ℃, the retention time is longer than 1 hour, usually 1 to 3 hours, such as 1 hour, 2 hours and 3 hours. The ammonium chloride can be fully decomposed at the temperature (the decomposition starting temperature of the ammonium chloride is 100 ℃, the ammonium chloride is decomposed into HCl), and the potassium permanganate is not decomposed, and the following reaction formula is generated: 2KMnO₄+16HCl＝2KCl+2MnCl₂+5Cl₂↑+8H2O；

And thirdly, raising the temperature to 400-450 ℃, reacting for 1-9 hours, usually reacting for 2-5 hours, such as 2 hours, 3 hours, 4 hours and 5 hours, and completing zinc impregnation.

In the method and the penetrating agent system of the embodiment, the temperature is low, and the method can be completed only by 400-450 ℃, so that the defect that the mechanical property of the auxiliary steel is easily deteriorated due to too high temperature is avoided.

In this example, the specific reaction described above can improve the reaction effect of the present invention, and the infiltrant can be effectively used and infiltrated into the accompanying steel to obtain the accompanying steel as described in example 1.

Example 4

The preparation method comprises the following steps: the multi-element powder penetrant and the accessory steel are put into a multi-element alloy co-infiltration furnace by adopting a rotary furnace body co-infiltration process, and the multi-element powder penetrant and the accessory steel rotate together to ensure that the penetrant is uniformly mixed and reacts uniformly. After the two are mixed, the co-permeation furnace is vacuumized to make the vacuum degree less than 100Pa, then the temperature in the co-permeation device is raised to about 130 ℃, and the reaction lasts for 2 hours. Then the temperature is raised to about 420 ℃ again, and the reaction time is 5 hours.

Experimental example 1: multi-element powder penetrating agent: 65 parts of zinc powder, 18 parts of zinc-aluminum alloy powder, 16 parts of aluminum-magnesium alloy powder, 0.5 part of cerium oxide and/or lanthanum oxide, 3 parts of an activating agent, 30 parts of a dispersing agent and 1 part of manganese dioxide.

Wherein, the activating agent is ammonium chloride and potassium permanganate, and in the activating agent, the proportion of potassium permanganate is 16 wt%, and the proportion of ammonium chloride is 84%.

The dispersant is alumina and magnesia in a weight ratio of 3: 1.

In the zinc-aluminum alloy powder, the aluminum content is 25 wt%, and the balance is zinc;

in the aluminum-magnesium alloy powder, the aluminum content is 50 wt%, and the balance is magnesium.

The processed secondary steel containing the alloy layer of the present application on the surface was prepared by the above method using the multi-component powder infiltration agent and the secondary steel in this experimental example.

Experimental example 2: multi-element powder penetrating agent: 73 parts of zinc powder, 15 parts of zinc-aluminum alloy powder, 20 parts of aluminum-magnesium alloy powder, 0.4 part of lanthanum oxide, 4 parts of an activating agent, 30 parts of a dispersing agent and 0.5 part of manganese dioxide.

Wherein, the activating agent is ammonium chloride and potassium permanganate, and in the activating agent, the ratio of potassium permanganate is 18 wt%, and the ammonium chloride is 82%.

The dispersant is aluminum nitride and magnesium oxide, and the weight ratio of the aluminum nitride to the magnesium oxide is 1: 2.

In the zinc-aluminum alloy powder, the aluminum content is 15 wt%, and the balance is zinc;

in the aluminum-magnesium alloy powder, the aluminum content is 35 wt%, and the balance is magnesium.

The processed secondary steel containing the alloy layer of the present application on the surface was prepared by the above method using the multi-component powder infiltration agent and the secondary steel in this experimental example.

Experimental example 3: multi-element powder penetrating agent: 60 parts of zinc powder, 20 parts of zinc-aluminum alloy powder, 15 parts of aluminum-magnesium alloy powder, 0.7 part of cerium oxide, 2 parts of an activator, 25 parts of a dispersant and 0.5 part of manganese dioxide.

Wherein, the activating agent is ammonium chloride and potassium permanganate, and in the activating agent, the ratio of potassium permanganate is 10 wt%, and the ammonium chloride is 85%.

The dispersant is alumina and silicon oxide, and the weight ratio of the alumina to the silicon oxide is 1: 1.

In the zinc-aluminum alloy powder, the aluminum content is 30 wt%, and the balance is zinc;

in the aluminum-magnesium alloy powder, the aluminum content is 55 wt%, and the balance is magnesium.

The processed secondary steel containing the alloy layer of the present application on the surface was prepared by the above method using the multi-component powder infiltration agent and the secondary steel in this experimental example.

Blank control: satellite steel without any treatment.

Adding no manganese: the potassium permanganate in the experimental example 1 is removed, and the product performance is greatly influenced by simple removal, so that the content of magnesium is increased by one third, and 1 part of active reagent magnesium chloride is added, so that the comprehensive performance of the product is high.

The untreated secondary steels used in the above experimental examples, blank control, and manganese-free method were homogeneous. The main component of the secondary steel is iron.

The results of the neutral salt spray test after sand blasting were carried out on the steels obtained in Experimental example 1, Experimental example 2, Experimental example 3, blank control and the accompanying steel obtained by the manganese-free method, respectively, as shown in the following tables.

Use performance	Experimental example 1	Experimental example 2	Experimental example 3	Blank control	Without addition of manganese
						Hardness (HV)	438	430	434	348	386
Salt spray resistance test	＞3500h	＞3500h	＞3500h	＜100h	＜2000h
						Sulfur dioxide resistance	High strength	High strength	High strength	Weak (weak)	Is preferably used

As is clear from the above table, the overall effect of the experimental examples is very excellent. As can be seen from the above table, the microhardness HV348 of the original surface of the substrate is HV386 without manganese after infiltration, but the hardness of the substrate can reach HV 430-HV 440, so that the hardness of the substrate is greatly improved, the wear resistance of the substrate is greatly improved, and the effect is excellent. And the salt spray resistance in the experimental example is excellent, the salt spray resistance test shows that the salt spray resistance is more than 3500h, compared with the manganese-free and blank control, the effect is very surprising, and the service life of the auxiliary steel can reach 100 years or more by reasonable conjecture and comprehensive practical application. Fig. 3 is a microscopic cross-sectional photograph of the salt spray of the experimental example after 3000 hours, and it is understood that the thickness of the alloy layer can reach about 27 μm after 3000 hours of the salt spray test, and the effect is obvious. In the test without manganese, the salt spray test was only 2000 hours.

Fig. 2 is a schematic sectional electron microscope showing the infiltration of the infiltration agent into the surface of the accompanying steel by the method of the present application in experimental example 1. The thickness of the alloy layer is uniform and thick, and the average thickness is about 60-70 mu m. The alloy of experimental example 1 was infiltrated with 66 wt% of zinc, 15.2 wt% of aluminum, 7.8 wt% of magnesium, 0.55 wt% of manganese, 10 wt% of iron, and the balance of nickel or other components contained in the matrix. In the surface layer, the contents of the metals are 74.1% of zinc, 18.9% of aluminum, 9.3% of magnesium, 0.7% of manganese, 5% of iron and the balance of nickel. The metal content in the alloy layer is basically uniform and less from top to bottom, and no phenomenon of deposition exists somewhere. According to the direction from the surface to the inside, at the depth of about 10 μm, the contents of the elements are 70.2% of zinc, 17.4% of aluminum, 8.9% of magnesium and 0.68% of manganese; at a depth of about 30 μm, the contents of the elements are 63.5% zinc, 12.3% aluminum, 6.7% magnesium and 0.41% manganese, and at a depth of about 50 μm, the contents of the elements are 28.2% zinc, 7.1% aluminum, 2.7% magnesium and 0.19% manganese. And the surface of this application experimental example is smooth, level, and the colour is slightly lighter, and is beautiful.

As can be seen from the above experiments, the multi-element metal infiltration agent of the present invention can achieve the metal infiltration amount as described in example 1, and has significantly improved salt spray resistance and wear resistance, and also has good sulfur dioxide resistance, and is suitable for use in harsh environments.

Example 5

In order to further study the secondary steel in this application, the applicant also performed a number of tests on the treated secondary steel, such as the thickness of the alloy layer, and the distribution of the metallic elements in the different thicknesses.

Comparative example 1: the contents of the respective metal powders of the multi-element powder impregnation agent are the same as those of experimental example 1 in example 4, and the preparation method is the same, and the differences are only that: with the metal Mn, the Mn added is the same as the potassium permanganate in mole number, the activator is only ammonium chloride, and the amount is the same as that of the ammonium chloride in experimental example 1.

Comparative example 2: the contents of the respective metal powders of the multi-element powder impregnation agent are the same as those of experimental example 1 in example 4, and the preparation method is the same, and the differences are only that: ammonium chloride was not added.

Comparative example 3: the contents of the respective metal powders of the multi-element powder impregnation agent are the same as those of experimental example 1 in example 4, and the preparation method is the same, and the differences are only that: potassium permanganate is not added.

Comparative example 4: the contents of the respective metal powders of the multi-element powder impregnation agent are the same as those of experimental example 1 in example 4, and the preparation method is the same, and the differences are only that: ammonium chloride was replaced by ammonium fluoride.

Comparative example 5: the contents of the respective metal powders of the multi-element powder impregnation agent are the same as those of experimental example 1 in example 4, and the preparation method is the same, and the differences are only that: ammonium chloride was replaced with ammonium bromide.

Comparative example 6: the contents of the respective metal powders of the multi-element powder impregnation agent are the same as those of experimental example 1 in example 4, except that: the preparation method directly heats the mixture to about 420 ℃.

The wear resistance and corrosion resistance of the above examples were tested and the content of metal infiltrated in the alloy layer was tested.

As is clear from the above table, the overall effect of experimental example 1 is very excellent, and it is described in example 4. Comparative example 1 has a certain manganese content, but the content is extremely low, and the content of other aluminum, magnesium and the like in the alloy layer is also greatly reduced, and magnesium is mainly concentrated in a shallow layer and is hardly detected after 20 μm; and the overall thickness of the alloy layer is significantly different from that of experimental example 1. For comparative examples 2 to 5, the resistance model was also significantly smaller than that of the experimental example, and the thickness of the infiltrated layer was also significantly smaller than that of the experimental example, and in addition, the infiltrated layer contained almost no manganese element, and had poor salt spray resistance and significantly inferior corrosion resistance to the experimental example. For comparative example 6, although the contents of the respective elements in the alloy layer were substantially within the protection range of the present application due to the change of conditions in the preparation method, the overall properties were less than those of the experimental examples.

The salt spray tests are shown in the following table:

as can be seen from the table, in the experimental example 1, after 3500h, no red rust still appears, and the salt spray resistance is more than 3500 h; comparative example 6 shows red rust at 3500 hours, the salt spray resistance of which is > 3000 hours and less than 3500 hours; comparative examples 3 and 5, which both showed a large amount of white rust at around 2000h and an obvious red rust at 3000h, with salt spray resistance < 3000 h; red rust appeared at 2000h in comparative example 1, comparative example 2 and comparative example 4, and the salt spray resistance was < 2000 h.

It should be noted that the contents of the components in the penetrant of the present application are set according to the characteristics of interaction or mutual restriction among the components, and the effect of the penetrant of the present application is achieved by the combined action of the components, so that for manganese element, which is an important component in the present application, if the infiltration cannot be performed normally or the infiltration amount is small, the performance of the accessory steel is greatly affected. In fact, if the alloy layer does not contain manganese originally, the better performance can be realized by adjusting the proportion of other components, the addition amount of the type of the auxiliary agent and the like. However, according to the effects of the accessory steel and the like, the applicant finds that the comprehensive performance of the added manganese is better through tests and research. Therefore, on the premise of adding manganese, the research and test adopts the form of adding manganese and the proportion of other components, and if the proportion or other components are not proper, the performance difference is very large. Thus, under the conditions of the present application, it is highly likely that the properties of the secondary steel will be greatly affected by, for example, a large adjustment of the amount of a component or the addition of a small amount of a component or the replacement of one or more components.

Example 6

Experimental example: as in experimental example 1 of example 4.

Comparative group 1: multi-element powder penetrating agent: 50 parts of zinc powder, 45 parts of zinc-aluminum alloy powder, 35 parts of aluminum-magnesium alloy powder, 3 parts of an activating agent, 0.4 part of cerium oxide, 30 parts of a dispersing agent and 1.0 part of manganese dioxide. The others were in accordance with experimental example 1.

Comparative group 2: multi-element powder penetrating agent: 50 parts of zinc powder, 5 parts of zinc-aluminum alloy powder, 5 parts of aluminum-magnesium alloy powder, 3 parts of an activating agent, 0.4 part of lanthanum oxide, 30 parts of a dispersing agent and 1.0 part of manganese dioxide.

Comparative group 3: multi-element powder penetrating agent: 35 parts of zinc powder, 5 parts of zinc-aluminum alloy powder, 5 parts of aluminum-magnesium alloy powder, 3 parts of an activating agent, 0.4 part of cerium oxide, 30 parts of a dispersing agent and 0.1 part of manganese dioxide.

Comparative group 4: multi-element powder penetrating agent: 50 parts of zinc powder, 45 parts of zinc-aluminum alloy powder, 30 parts of aluminum-magnesium alloy powder, 3 parts of an activating agent, 0.4 part of cerium oxide, 30 parts of a dispersing agent and 1.0 part of manganese dioxide. The activating agent comprises ammonium chloride and potassium permanganate, wherein in the activating agent, the potassium permanganate accounts for 60 wt%, and the ammonium chloride accounts for 40%

The other parts of the above comparative group (including the preparation method) were identical to those of the experimental group 1, and the hardness and neutral salt spray resistance were measured as follows.

The metal contents of the alloy layers in the above comparative groups are all inconsistent with the scope of protection of the present application, i.e. are not within the scope of example 1 or claim 1 of the present application. The corrosion resistance of the comparative group as a whole was weak. The contents of magnesium and aluminum in comparative example 1 were greatly increased and mainly concentrated in the surface layer and the depth range of 15 μm, and a local excess of magnesium occurred, affecting the performance, and the waste was severe and the cost was high.

The magnesium and aluminum contents in comparative example 2 are greatly reduced, and the comprehensive performance is reduced.

In comparative example 3, zinc powder is greatly reduced, metal components infiltrated into the alloy layer are mainly concentrated within 15 mu m, the thickness of the whole alloy is small and is basically between 10 and 30, the hardness is greatly reduced, and the corrosion resistance is weak.

The comparative example 4 has a reduced hardness and a significantly reduced plasticity, and is easily damaged due to a reduced instantaneous impact resistance when the vehicle passes. And the endurance of the instantaneous impact of comparative examples 3 and 2 is also significantly reduced.

Therefore, in the present application, the various components and the amounts of the various components are complementary, and the reduction, addition or replacement of one component has a great influence on the properties of the accompanying steel.

In the present invention, it should be noted that there are many factors that can affect the performance of the secondary steel after the metal element is infiltrated, and the factors are not only related to the ratio of the metal element in the alloy layer, but also greatly related to diffusion or infiltration, such as the same metal content as in the present embodiment, but if the infiltration is not uniform, there are some portions deposited more, and other portions too little, and the like, then the improvement performance of the metal may be very weak, and sometimes not only the performance of the metal surface layer is not improved, but also the performance of the metal surface layer is reduced. Moreover, the same metal content, if the depth of penetration is too shallow, will also greatly affect the properties of the metal. And the affiliated steel type in this application, cooperation the penetrant in this application, can realize the infiltration in step, degree of depth infiltration, and from the top layer to the inlayer of alloy-layer between, each metal comparatively even reduction, the too much condition of certain local metal can not appear, and through the mode of adding ammonium chloride and potassium permanganate under the specific condition for manganese must permeate again very big compound with iron and magnesium, formed the alloy-layer that increases metallic property, very big less or avoided the side effect that magnesium probably brought and the harm of iron in the affiliated steel. And the effect is better by matching with the method of the application.

In the invention, all the raw material powder is a market product and can be normally purchased, and the alloy powder comprises zinc-aluminum alloy powder, aluminum-magnesium alloy powder and other alloy powder which can be purchased.

Unless otherwise indicated, numerical ranges herein include not only the entire range within its two endpoints, but also several sub-ranges subsumed therein.

The preferred embodiments and examples of the present application have been described in detail with reference to the accompanying drawings, but the present application is not limited to the embodiments and examples described above, and various changes can be made within the knowledge of those skilled in the art without departing from the concept of the present application.