Preparation method of high-strength and high-wear-resistance tungsten carbide hydrophobic layer on surface of steel and iron material

Abstract

The invention discloses a preparation method of a high-strength and high-wear-resistance tungsten carbide hydrophobic layer on the surface of a steel and iron material, which comprises the following steps: 1) obtaining the steel and iron material with a carburized layer on the surface through pre-carburization; (2) a tungsten layer and an iron layer are prepared on the surface of the carburized steel material in sequence, aminated polystyrene microspheres are added in the iron layer preparation process, and a large number of aminated polystyrene microspheres are distributed on the interface between the tungsten layer and the iron layer; (3) carburizing treatment is conducted, the aminated polystyrene balls are decomposed at high temperature, the tungsten layer is converted into a tungsten carbide layer, and a rough interface is formed between the tungsten carbide layer and the iron layer; and (4) removing the iron layer, and modifying with a low-surface-energy substance to finally obtain a rough tungsten carbide layer and a hydrophobic layer on the surface of the rough tungsten carbide layer. The hydrophobic layer prepared through the method is high in strength and hardness, excellent in wear resistance, high in film-substrate binding force, good in hydrophobicity and corrosion resistance, easy and convenient to operate, high in applicability and high in production efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of metal material surface treatment, and in particular relates to a method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material. Background Art

[0002] Steel materials are widely used in the industrial field because of their excellent comprehensive mechanical properties. However, under some specific application conditions, steel materials need to have surface hardness, wear resistance and corrosion resistance. Preparing a ceramic layer on the surface of steel materials is an effective way to improve the surface hardness, wear resistance and corrosion resistance. At the same time, due to the poor hydrophobicity of the ceramic layer, it is easy to be corroded and damaged under the condition of long-term wetting with environmental liquids. Therefore, it is necessary to improve the surface hydrophobicity, thereby slowing down the corrosion rate and improving the corrosion resistance.

[0003] Research on the self-cleaning effect of lotus leaves found that the nano-scale rough structure and low surface energy of the waxy substance on the lotus leaf surface make it super hydrophobic. Inspired by this, domestic and foreign scholars have improved the surface hydrophobicity by constructing a rough surface and preparing hydrophobic substances with low surface energy on it.

[0004] The methods for preparing rough surface structures include etching, sol-gel, chemical vapor deposition, spraying, etc. Methods such as laser etching and plasma etching are complex, costly, and cannot be prepared quickly and on a large scale; the sol-gel method is complex, time-consuming, and the surface structure is difficult to control; the roughness of the film prepared by chemical vapor deposition is difficult to control; the substrate prepared by the spraying method has poor bonding with the rough film, and the rough structure of the solid surface is easily destroyed. Therefore, it is an urgent need to prepare a coating with high hardness, high bonding strength, high wear resistance, high hydrophobicity, and high corrosion resistance on the surface of steel materials. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing a tungsten carbide hydrophobic layer with high hardness and high wear resistance on the surface of a steel material, thereby solving the problems of rough surface structure of the hydrophobic film, poor mechanical properties and poor durability in the prior art.

[0006] The technical solution adopted by the present invention is a method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material, which specifically comprises the following steps:

[0007] Step 1: Carburize the surface of the steel material and then form a carburized layer on the surface of the steel material;

[0008] Step 2: preparing a tungsten layer on the surface of the carburized layer by a thin film preparation process;

[0009] Step 3: The surface of the tungsten layer is electroplated using an electroplating solution containing amino polystyrene microspheres to form an iron-amino polystyrene microsphere layer;

[0010] Step 4: Carburizing the iron-amino polystyrene microsphere layer and the tungsten layer to obtain an iron layer and a tungsten carbide layer with a rough structure at the interface;

[0011] Step 5: The iron layer obtained in step 4 is corroded cleanly with a chemical solution to obtain a tungsten carbide layer with a rough surface;

[0012] Step 6: Soak the tungsten carbide layer with a rough surface in a low surface energy substance solution for 1h-2h to perform surface modification, and obtain a high-strength and high-wear-resistant tungsten carbide hydrophobic layer after drying.

[0013] The present invention is also characterized in that:

[0014] The steel material in step 1 includes carbon steel and alloy steel, and the surface pretreatment is to polish the surface with sandpaper until the surface oil and oxides are removed and the surface roughness is reduced. The pre-carburizing temperature ranges from 800°C to 950°C, and the pre-carburizing method is one of gas carburizing, solid carburizing, vacuum carburizing or plasma carburizing. The mass fraction of carbon element in the carburized layer on the surface of the steel material after carburizing ranges from 0.8% to 2.0%;

[0015] The thin film preparation process in step 2 is one of ion plating, sputtering plating, and chemical vapor deposition, and the thickness of the prepared tungsten layer ranges from 5 μm to 20 μm;

[0016] The specific method of the electroplating treatment in step 3 is: the steel material with the tungsten layer is used as the cathode, pure iron is used as the anode, the electroplating solution is a ferrous chloride solution, and a solution containing amino polystyrene microspheres is added to the ferrous chloride solution, and the thickness of the electroplated iron layer ranges from 15μm to 30μm.

[0017] The mass concentration range of ferrous chloride solution is 300g / L-350g / L, the pH range is 1.3-1.5, the temperature range is 75℃-80℃, and the current density range is 0.01A / cm 2 -0.1A / cm 2 .

[0018] The volume of the amino polystyrene microsphere solution added to every 100 mL of the electroplating solution is in the range of 2 mL to 4 mL, the solid content of the amino polystyrene microsphere solution is 25 mg / mL, and the average diameter of the amino polystyrene microspheres is in the range of 5 μm to 10 μm.

[0019] The temperature range of the carburizing treatment in step 4 is 900°C-1100°C;

[0020] The chemical solution in step 5 is one of a hydrochloric acid solution, a sulfuric acid solution or a nitric acid solution, wherein the mass fraction of hydrochloric acid in the hydrochloric acid solution is in the range of 15%-25%, the mass fraction of sulfuric acid in the sulfuric acid solution is in the range of 40%-70%, and the mass fraction of nitric acid in the nitric acid solution is in the range of 30%-50%;

[0021] The low surface energy substance solution in step 6 is any one of perfluorodecyltriethoxysilane solution, 1H,1H,2H,2H perfluorodecyltrihexylsilane ethanol solution, and (3,3,3 trifluoropropyl)methyldimethoxysilane solution. The mass fraction of the low surface energy substance in the low surface energy substance solution is in the range of 3%-5%.

[0022] The beneficial effects of the present invention are:

[0023] (1) The rough surface tungsten carbide layer prepared by the present invention has high strength and hardness, good wear resistance, and the tungsten carbide layer is formed by carburizing. The tungsten carbide is precipitated in situ, has high density, and high grain boundary strength. During the carburizing process, elements diffuse between the tungsten layer and the substrate to form a metallurgical bonding interface, and the film-base bonding strength is high;

[0024] (2) Compared with other surface technologies for preparing rough structures: Compared with the etching method, the present invention has lower cost and can be prepared quickly and on a large area; compared with the sol-gel method, the process is simple and the operation is easy; compared with the chemical vapor deposition method, the surface structure prepared by the present invention has high roughness and good controllability; compared with the spraying method, it has high density, high ceramic volume fraction, high hardness, and good membrane-base bonding strength;

[0025] (3) The present invention can adjust the concentration of amino polystyrene balls added to the electroplating solution, the pH value of the electroplating solution, the current density and other parameters to control the surface roughness structure, thereby achieving the regulation of the surface structure;

[0026] (4) The present invention has small requirements on the shape of the workpiece, has strong applicability, and can process all surfaces of the metal substrate at the same time, with high production efficiency;

[0027] (5) The method for preparing the coating of the present invention is simple in process, easy to operate, and has strong applicability. The prepared rough structure hydrophobic layer has a stable structure, excellent wear resistance and high corrosion resistance, and has a good hydrophobic effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a flow chart of the method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material of the present invention;

[0029] Figure 2 It is a partial enlarged view of a flow chart of the method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material of the present invention;

[0030] Figure 3 These are two partial enlarged views of the process flow of the method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material of the present invention;

[0031] Figure 4 It is a schematic diagram of the surface roughness structure of the hydrophobic layer prepared by the present invention. DETAILED DESCRIPTION

[0032] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] The method for preparing the high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of the steel material of the present invention is as follows: Figure 1 As shown, the specific implementation steps are as follows:

[0034] Step 1: Select a steel material as a substrate, and polish its surface with sandpaper to remove surface oil and oxides and reduce surface roughness; then pre-carburize it at a temperature range of 800°C-950°C, and the carburizing method is one of gas carburizing, solid carburizing, vacuum carburizing, and plasma carburizing to obtain a steel material with a carburized layer, and the mass fraction of carbon in the carburized layer is in the range of 0.8%-2.0%;

[0035] Step 2: preparing a tungsten layer on the surface of the steel material with the carburized layer by a thin film preparation process, wherein the thickness of the tungsten layer ranges from 5 μm to 20 μm, and the thin film preparation process is one of ion plating, sputtering plating, and chemical vapor deposition, preferably, magnetron sputtering is selected;

[0036] Step 3: Electroplating an iron layer on the surface of the steel material with a surface tungsten layer. Specifically, prepare a ferrous chloride electrolyte with a mass concentration range of 300-350g / L and a pH range of 1.3-1.5, add 2mL-4mL of an amino polystyrene microsphere solution with a solid content of 25mg / mL to every 100mL of the electroplating solution, and the average diameter of the amino polystyrene microspheres is in the range of 5μm-10μm. The steel material obtained in step 2 is used as the cathode, pure iron is used as the anode, and the current density is in the range of 0.01A / cm 2 -0.1A / cm 2 The electroplating temperature is 75-80℃, and the thickness of the electroplated iron layer is 15μm-30μm. After electroplating, a steel material having an iron layer, amino polystyrene microspheres and a tungsten layer on the surface is obtained, such as Figure 2 As shown, a large number of amino polystyrene microspheres are distributed at the interface between the tungsten layer and the iron layer;

[0037] Step 4: Figure 3As shown, the steel material with an iron layer, amino polystyrene microspheres and a tungsten layer on the surface obtained in step 3 is carburized, the carburizing temperature range is 900°C-1100°C, and the carburizing method is one of gas carburizing, solid carburizing, vacuum carburizing, and plasma carburizing. During the carburizing process, the amino polystyrene microspheres decompose, the tungsten layer is converted into a tungsten carbide layer, and a rough interface is formed between the tungsten carbide layer and the iron layer. After carburizing, an iron layer and a tungsten carbide layer with a rough structure on the interface are obtained;

[0038] Step 5: corroding the surface iron layer of step 4 with a chemical solution, wherein the chemical solution is one of a hydrochloric acid solution, a sulfuric acid solution or a nitric acid solution, wherein the mass fraction of hydrochloric acid in the hydrochloric acid solution is in the range of 15%-25%, the mass fraction of sulfuric acid in the sulfuric acid solution is in the range of 40%-70%, and the mass fraction of nitric acid in the nitric acid solution is in the range of 30%-50%, thereby obtaining a tungsten carbide layer with a rough surface;

[0039] Step 6: Soak the steel material with the rough surface tungsten carbide layer obtained in step 5 in any one of perfluorodecyl triethoxysilane solution, 1H, 1H, 2H, 2H-perfluorodecyl trihexyloxysilane ethanol solution, and (3, 3, 3-trifluoropropyl) methyl dimethoxysilane solution for 1h-2h, and the mass fraction of the solute in the solution is 3%-5%. Take it out and dry it to obtain a high-strength and high-wear-resistant tungsten carbide hydrophobic layer.

[0040] In the preparation method of the high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of the steel material of the present invention: the role of step 1 is to enable the steel material matrix to serve as a carbon source in the subsequent carburizing process, provide carbon atoms for the tungsten layer, and achieve the effect of bidirectional carburizing; the role of the electroplated iron layer in step 3 is that iron can serve as a carburizing medium, and the advantages are: on the one hand, the solid solubility of carbon in iron is relatively high, and on the other hand, the iron layer can play a buffering role, thereby avoiding the problem of loose and porous ceramic layers caused by excessively high carbon potential; the principle of the formation of the surface rough structure is that the amino polystyrene microspheres form holes in the iron layer (especially at the interface between the iron layer and the tungsten layer) after high-temperature decomposition, and then in the high-temperature carburizing process, the tungsten element diffuses on the inner surface of the iron layer hole, so that the inner hole wall attached area forms an iron-tungsten solid solution area, and the tungsten in the solid solution area reacts with carbon to convert the hole wall area into tungsten carbide, forming a micron-sized tungsten carbide rough structure (primary rough structure), and at the same time, the tungsten carbide grows perpendicular to the inner hole wall, forming a micron or nanometer-scale dendritic rough structure (secondary rough structure). Therefore, after the rear surface iron layer is removed in step 5, a tungsten carbide surface with a graded rough structure is obtained.

[0041] The rough surface tungsten carbide layer prepared by the present invention has high strength and hardness and good wear resistance. The tungsten carbide ceramic layer is formed by carburizing. The tungsten carbide is precipitated in situ, is dense, has a high volume fraction of tungsten carbide, and grows internally, so the hardness is high and the membrane-base bonding force is good. It is not demanding on the workpiece and has strong applicability. It can be quickly prepared on all surfaces of the metal in a large area at the same time, and has high production efficiency. The surface roughness structure can be controlled by adjusting the concentration of amino polystyrene microspheres added to the electroplating solution, the pH value of the electroplating solution, the current density and other parameters, so as to achieve different hydrophobic film performance requirements.

[0042] Embodiment 1:

[0043] The method for preparing the high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of the steel material of the present invention is specifically implemented according to the following steps:

[0044] Step 1: Carburize the surface of the steel material and then form a carburized layer on the surface of the steel material;

[0045] The steel material in step 1 is 45 steel, and the surface pretreatment is to grind the surface of the steel material with sandpaper until the surface oil and oxides are removed, the pre-carburizing temperature is 800° C., and the mass fraction of carbon element in the carburized layer is 2.0%;

[0046] Step 2: preparing a tungsten layer on the surface of the carburized layer in step 1 by a thin film preparation process;

[0047] In step 2, the thin film preparation process is chemical vapor deposition, and the thickness of the tungsten layer is 15 μm;

[0048] Step 3: electroplating an iron layer on the surface of the tungsten layer in step 2, wherein the electroplating solution contains amino polystyrene microspheres to form an iron-amino polystyrene microsphere layer;

[0049] The specific method of electroplating in step 3 is: the steel material with a tungsten layer is used as the cathode, pure iron is used as the anode, the electroplating solution is a ferrous chloride solution, the mass concentration of the ferrous chloride solution is 300g / L, the pH value is 1.3, the temperature is 75°C, and the current density is 0.01A / cm 2 , and adding a solution containing 5 μm-diameter amino polystyrene microspheres to the ferrous chloride solution, adding 2 mL of the 5 μm-diameter amino polystyrene microsphere solution to every 100 mL of the electroplating solution, the solid content of the amino polystyrene microsphere solution is 25 mg / mL, and an iron-amino polystyrene microsphere layer is obtained, the thickness of the iron layer is 15 μm, and the amino polystyrene microspheres are distributed at the interface between the tungsten layer and the iron layer;

[0050] Step 4: Carburizing the iron-amino polystyrene microsphere layer and the tungsten layer. During the carburizing process, the amino polystyrene microspheres are decomposed, the tungsten layer is transformed into a tungsten carbide layer, and a rough structure interface is formed between the tungsten carbide layer and the iron layer, thereby obtaining an iron layer and a tungsten carbide layer having a rough structure interface;

[0051] The temperature range of carburizing treatment in step 4 is 900°C and the time is 30h;

[0052] Step 5: Use a chemical solution to corrode the iron layer with a rough structure at the interface and the iron layer on the surface of the tungsten carbide layer to obtain a tungsten carbide layer with a rough surface;

[0053] The chemical solution in step 5 is a hydrochloric acid solution, and the mass fraction of hydrochloric acid in the hydrochloric acid solution is 15%;

[0054] Step 6: Soak the tungsten carbide layer with a rough surface in a low surface energy substance solution for 1 hour to perform surface modification, and obtain a high-strength and high-wear-resistant tungsten carbide hydrophobic layer after drying;

[0055] The low surface energy substance solution in step 6 is a (3,3,3-trifluoropropyl)methyldimethoxysilane solution, and the mass fraction of the (3,3,3-trifluoropropyl)methyldimethoxysilane solution is 3%.

[0056] Embodiment 2:

[0057] The method for preparing the high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of the steel material of the present invention is specifically implemented according to the following steps:

[0058] Step 1: Carburize the surface of the steel material and then form a carburized layer on the surface of the steel material;

[0059] The steel material in step 1 is T10 steel, and the surface pretreatment is to grind the surface of the steel material with sandpaper until the surface oil and oxides are removed, the pre-carburizing temperature is 950° C., and the mass fraction of carbon in the carburized layer is 0.8%;

[0060] Step 2: preparing a tungsten layer on the surface of the carburized layer in step 1 by a thin film preparation process, wherein the thin film preparation process in step 2 is ion plating, and the thickness of the tungsten layer is 10 μm;

[0061] Step 3: electroplating an iron layer on the surface of the tungsten layer in step 2, wherein the electroplating solution contains amino polystyrene microspheres to form an iron-amino polystyrene microsphere layer;

[0062] The specific method of electroplating in step 3 is: the steel material with a tungsten layer is used as the cathode, pure iron is used as the anode, the electroplating solution is a ferrous chloride solution, the mass concentration of the ferrous chloride solution is 320g / L, the pH value is 1.4, the temperature is 77°C, and the current density is 0.1A / cm2 , and adding a solution containing 6 μm-diameter amino polystyrene microspheres to the ferrous chloride solution, adding 2.5 mL of the 6 μm-diameter amino polystyrene microsphere solution to every 100 mL of the electroplating solution, the solid content of the amino polystyrene microsphere solution being 25 mg / mL, to obtain an iron-amino polystyrene microsphere layer, the thickness of the iron layer being 30 μm, and amino polystyrene microspheres being distributed at the interface between the tungsten layer and the iron layer;

[0063] Step 4: Carburizing the iron-amino polystyrene microsphere layer and the tungsten layer. During the carburizing process, the amino polystyrene microspheres are decomposed, the tungsten layer is transformed into a tungsten carbide layer, and a rough structure interface is formed between the tungsten carbide layer and the iron layer, thereby obtaining an iron layer and a tungsten carbide layer having a rough structure interface;

[0064] The temperature range of the carburizing treatment in step 4 is 1000°C and the time is 15h;

[0065] Step 5: Use a chemical solution to corrode the iron layer with a rough structure at the interface and the iron layer on the surface of the tungsten carbide layer to obtain a tungsten carbide layer with a rough surface;

[0066] The chemical solution in step 5 is a hydrochloric acid solution, and the mass fraction of hydrochloric acid in the hydrochloric acid solution is 20%;

[0067] Step 6: Soak the tungsten carbide layer with a rough surface in a low surface energy substance solution for 1.5 hours to perform surface modification, and obtain a high-strength and high-wear-resistant tungsten carbide hydrophobic layer after drying;

[0068] The low surface energy substance solution in step 6 is an ethanol solution of 1H,1H,2H,2H-perfluorodecyltrihexyloxysilane, and the mass fraction of the ethanol solution of 1H,1H,2H,2H-perfluorodecyltrihexyloxysilane is 4%.

[0069] Embodiment 3:

[0070] The method for preparing the high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of the steel material of the present invention is specifically implemented according to the following steps:

[0071] Step 1: Carburize the surface of the steel material and then form a carburized layer on the surface of the steel material;

[0072] The steel material in step 1 is 45 steel, and the surface pretreatment is to grind the surface of the steel material with sandpaper until the surface oil and oxides are removed, the pre-carburizing temperature is 850° C., and the mass fraction of carbon element in the carburized layer is 1.2%;

[0073] Step 2: preparing a tungsten layer on the surface of the carburized layer in step 1 by a thin film preparation process;

[0074] The thin film preparation process in step 2 is sputtering, and the thickness of the tungsten layer is 12 μm;

[0075] Step 3: electroplating an iron layer on the surface of the tungsten layer in step 2, wherein the electroplating solution contains amino polystyrene microspheres to form an iron-amino polystyrene microsphere layer;

[0076] The specific method of electroplating in step 3 is: the steel material with a tungsten layer is used as the cathode, pure iron is used as the anode, the electroplating solution is a ferrous chloride solution, the mass concentration of the ferrous chloride solution is 350g / L, the pH value is 1.5, the temperature is 80°C, and the current density is 0.04A / cm 2 , and adding a solution containing 7 μm-diameter amino polystyrene microspheres to the ferrous chloride solution, adding 4 mL of the 7 μm-diameter amino polystyrene microsphere solution to every 100 mL of the electroplating solution, the solid content of the amino polystyrene microsphere solution being 25 mg / mL, to obtain an iron-amino polystyrene microsphere layer, the thickness of the iron layer being 25 μm, and amino polystyrene microspheres being distributed at the interface between the tungsten layer and the iron layer;

[0077] Step 4: Carburizing the iron-amino polystyrene microsphere layer and the tungsten layer. During the carburizing process, the amino polystyrene microspheres are decomposed, the tungsten layer is transformed into a tungsten carbide layer, and a rough structure interface is formed between the tungsten carbide layer and the iron layer, thereby obtaining an iron layer and a tungsten carbide layer having a rough structure interface;

[0078] The temperature range of the carburizing treatment in step 4 is 1100°C and the time is 5h;

[0079] Step 5: Use a chemical solution to corrode the iron layer with a rough structure at the interface and the iron layer on the surface of the tungsten carbide layer to obtain a tungsten carbide layer with a rough surface;

[0080] The chemical solution in step 5 is a hydrochloric acid solution, and the mass fraction of hydrochloric acid in the hydrochloric acid solution is 20%;

[0081] Step 6: Soak the tungsten carbide layer with a rough surface in a low surface energy substance solution for 2 hours to perform surface modification, and obtain a high-strength and high-wear-resistant tungsten carbide hydrophobic layer after drying;

[0082] The low surface energy substance solution in step 6 is a perfluorodecyltriethoxysilane solution, and the mass fraction of the perfluorodecyltriethoxysilane solution is 5%.

[0083] Embodiment 4:

[0084] The method for preparing the high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of the steel material of the present invention is specifically implemented according to the following steps:

[0085] Step 1: Carburize the surface of the steel material and then form a carburized layer on the surface of the steel material;

[0086] The steel material in step 1 is T10 steel, and the surface pretreatment is to grind the surface of the steel material with sandpaper until the surface oil and oxides are removed, the pre-carburizing temperature is 825° C., and the mass fraction of carbon element in the carburized layer is 1.4%;

[0087] Step 2: preparing a tungsten layer on the surface of the carburized layer in step 1 by a thin film preparation process;

[0088] In step 2, the thin film preparation process is magnetron sputtering, and the thickness of the tungsten layer is 5 μm;

[0089] Step 3: electroplating an iron layer on the surface of the tungsten layer in step 2, wherein the electroplating solution contains amino polystyrene microspheres to form an iron-amino polystyrene microsphere layer;

[0090] The specific method of electroplating in step 3 is: the steel material with tungsten layer is used as cathode, pure iron is used as anode, the electroplating solution is ferrous chloride solution, the mass concentration of ferrous chloride solution is 300g / L, the pH value is 1.3, the temperature is 75°C, and the current is 0.06A / cm 2 , and add a solution containing 8 μm-diameter amino polystyrene microspheres to the ferrous chloride solution, add 2 mL of the 8 μm-diameter amino polystyrene microsphere solution to every 100 mL of the electroplating solution, the solid content of the amino polystyrene microsphere solution is 25 mg / mL, the iron-amino polystyrene microsphere layer, the thickness of the iron layer is 15 μm, and the amino polystyrene microspheres are distributed at the interface between the tungsten layer and the iron layer;

[0091] Step 4: Carburizing the iron-amino polystyrene microsphere layer and the tungsten layer. During the carburizing process, the amino polystyrene microspheres are decomposed, the tungsten layer is transformed into a tungsten carbide layer, and a rough structure interface is formed between the tungsten carbide layer and the iron layer, thereby obtaining an iron layer and a tungsten carbide layer having a rough structure interface;

[0092] The temperature range of the carburizing treatment in step 4 is 900°C and the time is 10h;

[0093] Step 5: Use a chemical solution to corrode the iron layer with a rough structure at the interface and the iron layer on the surface of the tungsten carbide layer to obtain a tungsten carbide layer with a rough surface;

[0094] The chemical solution in step 5 is a sulfuric acid solution, and the mass fraction of sulfuric acid in the sulfuric acid solution is 40%;

[0095] Step 6: Soak the tungsten carbide layer with a rough surface in a low surface energy substance solution for 1.5 hours to perform surface modification, and obtain a high-strength and high-wear-resistant tungsten carbide hydrophobic layer after drying;

[0096] The low surface energy substance solution in step 6 is a (3,3,3-trifluoropropyl)methyldimethoxysilane solution, and the mass fraction of the (3,3,3-trifluoropropyl)methyldimethoxysilane solution is 5%.

[0097] Embodiment 5:

[0098] The method for preparing the high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of the steel material of the present invention is specifically implemented according to the following steps:

[0099] Step 1: Carburize the surface of the steel material and then form a carburized layer on the surface of the steel material;

[0100] The steel material in step 1 is T10 steel, and the surface pretreatment is to grind the surface of the steel material with sandpaper until the surface oil and oxides are removed, the pre-carburizing temperature is 925° C., and the mass fraction of carbon element in the carburized layer is 1.6%;

[0101] Step 2: preparing a tungsten layer on the surface of the carburized layer in step 1 by a thin film preparation process, wherein the thin film preparation process in step 2 is chemical vapor deposition, and the thickness of the tungsten layer is 20 μm;

[0102] Step 3: electroplating an iron layer on the surface of the tungsten layer in step 2, wherein the electroplating solution contains amino polystyrene microspheres to form an iron-amino polystyrene microsphere layer;

[0103] The specific method of electroplating in step 3 is: the steel material with tungsten layer is used as cathode, pure iron is used as anode, the electroplating solution is ferrous chloride solution, the mass concentration of ferrous chloride solution is 300g / L, the pH value is 1.5, the temperature is 75°C, and the current is 0.08A / cm 2 , and adding a solution containing 9 μm-diameter amino polystyrene microspheres to the ferrous chloride solution, adding 3 mL of the 9 μm-diameter amino polystyrene microsphere solution to every 100 mL of the electroplating solution, the solid content of the amino polystyrene microsphere solution is 25 mg / mL, and an iron-amino polystyrene microsphere layer is obtained, the thickness of the iron layer is 20 μm, and the amino polystyrene microspheres are distributed at the interface between the tungsten layer and the iron layer;

[0104] Step 4: Carburizing the iron-amino polystyrene microsphere layer and the tungsten layer. During the carburizing process, the amino polystyrene microspheres are decomposed, the tungsten layer is transformed into a tungsten carbide layer, and a rough structure interface is formed between the tungsten carbide layer and the iron layer, thereby obtaining an iron layer and a tungsten carbide layer having a rough structure interface;

[0105] The temperature range of the carburizing treatment in step 4 is 1100°C and the time is 10h;

[0106] Step 5: Use a chemical solution to corrode the iron layer with a rough structure at the interface and the iron layer on the surface of the tungsten carbide layer to obtain a tungsten carbide layer with a rough surface;

[0107] The chemical solution in step 5 is a sulfuric acid solution, and the mass fraction of sulfuric acid in the sulfuric acid solution is 70%;

[0108] Step 6: Soak the tungsten carbide layer with a rough surface in a low surface energy substance solution for 1 hour to perform surface modification, and obtain a high-strength and high-wear-resistant tungsten carbide hydrophobic layer after drying;

[0109] The low surface energy substance solution in step 6 is a (3,3,3-trifluoropropyl)methyldimethoxysilane solution, and the mass fraction of the (3,3,3-trifluoropropyl)methyldimethoxysilane solution is 4%.

[0110] Embodiment 6:

[0111] The method for preparing the high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of the steel material of the present invention is specifically implemented according to the following steps:

[0112] Step 1: Carburize the surface of the steel material and then form a carburized layer on the surface of the steel material;

[0113] The steel material in step 1 is 45 steel, and the surface pretreatment is to grind the surface of the steel material with sandpaper until the surface oil and oxides are removed, the pre-carburizing temperature is 1000° C., and the mass fraction of carbon element in the carburized layer is 1.8%;

[0114] Step 2: Prepare a tungsten layer on the surface of the carburized layer in step 1 by a thin film preparation process. The thin film preparation process in step 2 is magnetron sputtering. The thickness of the tungsten layer of the steel material having the tungsten layer is 8 μm.

[0115] Step 3: electroplating the steel material having the tungsten layer obtained in step 2 to obtain a steel material having an iron layer, amino polystyrene microspheres and a tungsten layer;

[0116] The specific method of electroplating in step 3 is: the steel material with tungsten layer is used as cathode, pure iron is used as anode, the electroplating solution is ferrous chloride solution, the mass concentration of ferrous chloride solution is 300g / L, the pH value is 1.3, the temperature is 80℃, and the current is 0.1A / cm 2 , and add a solution containing 10 μm-diameter amino polystyrene microspheres to the ferrous chloride solution, add 2 mL of the solution containing 10 μm-diameter amino polystyrene microspheres to every 100 mL of the electroplating solution, the solid content of the amino polystyrene microsphere solution is 25 mg / mL, the iron-amino polystyrene microsphere layer, the thickness of the iron layer is 30 μm, and the amino polystyrene microspheres are distributed at the interface between the tungsten layer and the iron layer;

[0117] Step 4: Carburizing the iron-amino polystyrene microsphere layer and the tungsten layer. During the carburizing process, the amino polystyrene microspheres are decomposed, the tungsten layer is transformed into a tungsten carbide layer, and a rough structure interface is formed between the tungsten carbide layer and the iron layer, thereby obtaining an iron layer and a tungsten carbide layer having a rough structure interface;

[0118] The temperature range of the carburizing treatment in step 4 is 1000°C and the time is 10h;

[0119] Step 5: Use a chemical solution to corrode the iron layer with a rough structure at the interface and the iron layer on the surface of the tungsten carbide layer to obtain a tungsten carbide layer with a rough surface;

[0120] The chemical solution in step 5 is a nitric acid solution, and the mass fraction of sulfuric acid in the nitric acid solution is 30%;

[0121] Step 6: Soak the tungsten carbide layer with a rough surface in a low surface energy substance solution for 1.5 hours to perform surface modification, and obtain a high-strength and high-wear-resistant tungsten carbide hydrophobic layer after drying;

[0122] The low surface energy substance solution in step 6 is a (3,3,3-trifluoropropyl)methyldimethoxysilane solution, and the mass fraction of the (3,3,3-trifluoropropyl)methyldimethoxysilane solution is 3%.

[0123] Performance Test:

[0124] (1) Hardness: The microhardness of the above cases was measured by Vickers microhardness test. The load was 50 g, the indenter was a conical indenter, and the holding time was 10 s.

[0125] (2) Contact angle: The contact angle of the sample surface was measured using a contact angle meter with a droplet volume of 5 L;

[0126] The high-strength and high-wear-resistant tungsten carbide hydrophobic layer prepared in Examples 1-6 was subjected to relevant performance tests, and the test results are shown in the following table:

[0127] project Surface hardness Contact angle (°) Example 1 2800HV 162 Example 2 2500HV 158 Example 3 2600HV 156 Example 4 2000HV 153 Example 5 2900HV 160 Example 6 2200HV 152

[0128] The surface roughness structure prepared by the method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material of the present invention has excellent mechanical properties. Its surface hardness can reach 2900 HV on average, and it has good wear resistance. Through the test of the contact angle measuring instrument, the contact angle of the prepared tungsten carbide hydrophobic layer to water is greater than 150°, and it has excellent hydrophobic performance.

Claims

1. A method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material, characterized in that: Follow the steps below to implement it: Step 1: Carburize the surface of the steel material and then form a carburized layer on the surface of the steel material; Step 2: preparing a tungsten layer on the surface of the carburized layer by a thin film preparation process; Step 3: electroplating the surface of the tungsten layer using an electroplating solution containing amino polystyrene microspheres to form an iron-amino polystyrene microsphere layer; Step 4: Carburizing the iron-amino polystyrene microsphere layer and the tungsten layer to obtain an iron layer and a tungsten carbide layer with a rough structure at the interface; Step 5: The iron layer obtained in step 4 is corroded cleanly with a chemical solution to obtain a tungsten carbide layer with a rough surface; Step 6: Soak the tungsten carbide layer with a rough surface in a low surface energy substance solution for 1 hour to 2 hours to perform surface modification, and obtain a high-strength and high-wear-resistant tungsten carbide hydrophobic layer after drying.

2. The method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material according to claim 1, characterized in that: The steel material in step 1 includes carbon steel or alloy steel. The surface pretreatment is to grind the surface of the metal substrate with sandpaper until the oil and oxide on the surface of the metal substrate are removed. The pre-carburizing temperature ranges from 900°C to 1100°C. The pre-carburizing method is one of gas carburizing, solid carburizing, vacuum carburizing or plasma carburizing. The mass fraction of carbon element in the carburized layer on the surface of the steel material after pre-carburizing ranges from 0.8% to 2.0%.

3. The method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material according to claim 1, characterized in that: The thin film preparation process in step 2 is one of ion plating, sputtering plating and chemical vapor deposition, and the thickness of the tungsten layer is 5 μm-20 μm.

4. The method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material according to claim 1, characterized in that: The specific method of the electroplating treatment in step 3 is: the steel material with the tungsten layer is used as the cathode, pure iron is used as the anode, the electroplating solution is a ferrous chloride solution, and a solution containing amino polystyrene microspheres is added to the ferrous chloride solution, and the thickness of the electroplated iron layer ranges from 15μm to 30μm.

5. The method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material according to claim 4, characterized in that: The mass concentration of the ferrous chloride solution is in the range of 300 g / L-350 g / L, the pH value is in the range of 1.3-1.5, the temperature is in the range of 75°C-80°C, and the current density is in the range of 0.01-0.1 A / cm 2 .

6. The method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material according to claim 4, characterized in that: The volume of the amino polystyrene microsphere solution added to every 100 mL of the electroplating solution is in the range of 2 mL to 4 mL, the solid content of the amino polystyrene microsphere solution is 25 mg / mL, and the average diameter of the amino polystyrene microspheres is in the range of 5 μm to 10 μm.

7. The method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material according to claim 1, characterized in that: The temperature range of the carburizing treatment in step 4 is 900° C.-1100° C., and the time is 5 h-30 h.

8. The method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material according to claim 1, characterized in that: The chemical solution in step 5 is one of hydrochloric acid solution, sulfuric acid solution or nitric acid solution, wherein the mass fraction of hydrochloric acid in the hydrochloric acid solution is 15%-25%, the mass fraction of sulfuric acid in the sulfuric acid solution is 40%-70%, and the mass fraction of nitric acid in the nitric acid solution is 30%-50%.

9. The method for preparing a high-strength and high-wear-resistant tungsten carbide hydrophobic layer on the surface of a steel material according to claim 1, characterized in that: The low surface energy substance solution in step 6 is any one of perfluorodecyltriethoxysilane solution, 1H,1H,2H,2H perfluorodecyltrihexylsilane ethanol solution, and (3,3,3 trifluoropropyl)methyldimethoxysilane solution, and the mass fraction of the low surface energy substance in the low surface energy substance solution is 3%-5%.

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