A corrosion and wear resistant thermal sprayed nickel-based composite non-slip coating and a method for preparing the same

Abstract

The present application relates to a kind of corrosion and wear resistant thermal spraying nickel-based composite non-slip coating and its preparation method, belong to non-slip coating technical field.It includes alloy steel matrix, corrosion-resistant bottom layer and non-slip surface layer from bottom to top sequentially arranged;Wherein, the corrosion-resistant bottom layer is nickel-based superalloy, and the thickness of corrosion-resistant bottom layer is 50-200 μm;The non-slip surface layer is composed of the same nickel-based superalloy as corrosion-resistant bottom layer, nano alumina particles and micron alumina particles, and the thickness of non-slip surface layer is 300-600 μm.Using plasma enhanced high-speed arc spray technology realizes the high efficiency, high quality preparation of alloy bottom layer and metal / ceramic surface layer, and the obtained nickel-based composite non-slip coating has excellent properties such as non-slip, wear resistance and corrosion resistance, which can effectively improve the deck surface performance and service life of various large marine engineering equipment.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of corrosion and wear-resistant thermal spraying nickel-based composite non-slip coating and its preparation method, belong to non-slip coating technical field. BACKGROUND

[0002] Non-slip coating is a kind of functional coating with high friction coefficient characteristics, which is widely used in the deck surface of large marine equipment such as offshore platform and ship, thereby reducing the relative sliding between personnel, construction equipment and running vehicles and the deck. The quality and performance of non-slip coating are directly related to the safe operation of the platform and the life and property of personnel, and is one of the key technologies in the field of marine equipment surface manufacturing.

[0003] According to the material and preparation process, the existing non-slip coating system at home and abroad can be divided into: roll-coated resin-based coating and thermal sprayed metal-based coating. Among them, resin-based coating has been widely used due to its advantages of convenient construction, simple maintenance, low single cost, etc. However, during long-term service, resin-based coating exposes a series of defects, such as: low bonding strength (≤15 MPa), poor wear resistance and heat resistance (≤100 ℃), easy aging degradation, poor non-slip stability, strong environmental pollution, etc., which makes it difficult to meet the increasingly harsh service conditions. Compared with resin-based coating, thermal sprayed metal-based coating has natural advantages in high temperature resistance, aging resistance, etc., and the non-slip coating system represented by nickel-based and iron-based amorphous also has the characteristics of wear resistance, corrosion resistance, impact resistance and high friction, which is very suitable for the performance requirements of the deck of marine engineering equipment.

[0004] In recent years, in order to further improve the service performance indicators of non-slip coating, ceramic materials (such as Al2O3, Cr2C3, WC, etc.) are usually used as non-slip particles and wear-resistant strengthening phase together with metal-based coating to form metal / ceramic composite coating. Among them, the high-strength and high-melting-point ceramic phase improves the wear resistance of the non-slip coating, and the high-toughness metal phase enhances the bonding strength and impact resistance of the non-slip coating. However, on the one hand, too high ceramic content will significantly increase the defects such as pores, micro-cracks, unmelted particles, etc. in the composite coating, thereby causing the density, bonding strength, corrosion resistance and comprehensive mechanical properties of the coating to decrease sharply. On the other hand, the deposition efficiency of traditional thermal spraying technology for preparing composite coating is low. The excessive ablation of low-melting-point metal phase and the inclusion and rebound of high-melting-point ceramic phase result in a large difference between the actual coating composition and the designed composition of the original material, making it difficult to accurately control the performance of the coating.

[0005] In summary, the existing thermal sprayed metal-based composite non-slip coating cannot meet the increasingly harsh marine service conditions. Therefore, it is urgent to optimize and improve the material, structure and process of non-slip coating, and to provide a kind of metal / ceramic composite non-slip coating with high quality, wear resistance and corrosion resistance and its preparation method. SUMMARY

[0006] Therefore, the present application aims to provide a corrosion and wear resistant thermal spraying nickel-based composite non-slip coating and a preparation method thereof. A double-layer structure composed of a corrosion resistant nickel-based high-temperature alloy layer and a wear resistant non-slip nickel-based high-temperature alloy / ceramic composite surface layer is designed to improve the coating bonding strength and service performance. Meanwhile, composite ceramic particles composed of nano-alumina and micron-alumina are used as non-slip phase to further reduce micro defects on the basis of ensuring the coating with high friction coefficient. The high-efficiency and high-quality preparation of the alloy bottom layer and the metal / ceramic surface layer is realized by using plasma enhanced high-speed arc spraying technology. The obtained nickel-based composite non-slip coating has excellent properties such as non-slip, wear resistance and corrosion resistance, and can effectively improve the deck surface performance and service life of various large marine engineering equipment.

[0007] To achieve the above-mentioned purpose, the technical scheme of the present application is as follows.

[0008] A corrosion and wear resistant thermal spraying nickel-based composite non-slip coating comprises an alloy steel substrate, a corrosion resistant bottom layer and a non-slip surface layer arranged in sequence from bottom to top. The corrosion resistant bottom layer is a nickel-based high-temperature alloy, and the chemical composition of the nickel-based high-temperature alloy comprises Ni, Cr, Mo, Fe, Nb and Al. The thickness of the corrosion resistant bottom layer is 50-200 μm. The non-slip surface layer is composed of the same nickel-based high-temperature alloy, nano-alumina particles and micron-alumina particles as the corrosion resistant bottom layer. In terms of the total mass of the non-slip surface layer, the mass fraction of the nickel-based high-temperature alloy is 50-70%, the mass fraction of the nano-alumina particles is 5-15%, and the mass fraction of the micron-alumina particles is 15-45%. The thickness of the non-slip surface layer is 300-600 μm.

[0009] Preferably, the alloy steel substrate is 921A alloy steel or 980 alloy steel.

[0010] Preferably, in terms of the total mass of the nickel-based high-temperature alloy, the mass percentage of the chemical composition of the alloy is as follows: Ni is 50-58%, Cr is 12-25%, Mo is 2-15%, Fe is 5-15%, Nb is 3.0-4.0%, Al≤0.4%, and the balance is Ni and inevitable impurity elements.

[0011] Preferably, the nickel-based high-temperature alloy is Inconel 625 alloy, Inconel 718 alloy or C276 alloy.

[0012] Preferably, the particle size of the nano-alumina particles is 5-100 nm, and the particle size of the micron-alumina particles is 15-45 μm.

[0013] Preferably, the thickness ratio of the corrosion-resistant base layer and the anti-skid surface layer is 1:1 to 1:2.

[0014] A preparation method of the corrosion-resistant and wear-resistant thermal spraying nickel-based composite anti-skid coating according to the present application, the method steps comprising:

[0015] (1) adding nano-alumina powder and micron-alumina powder into a modifier solution, ultrasonicating, spray drying, sieving, to obtain composite alumina powder with a particle size of 30-60 μm;

[0016] (2) sandblasting, cleaning and drying the alloy steel substrate to obtain a treated alloy steel substrate;

[0017] (3) using nickel-based high-temperature alloy wire as the spraying raw material, performing plasma transferred arc wire spraying to prepare a corrosion-resistant base layer on the treated alloy steel substrate;

[0018] (4) using nickel-based high-temperature alloy wire and composite alumina powder as the spraying raw material, performing plasma transferred arc wire / powder composite spraying to prepare an anti-skid surface layer on the corrosion-resistant base layer;

[0019] In step (3), the transferred arc power is 35-60 kW, the non-transferred arc power is 15-25 kW, the argon flow rate is 60-100 L / min, the hydrogen flow rate is 8-10 L / min, the wire feeding rate is 60-800 g / min, the wire-nozzle distance is 5-15 mm, the wire feeding angle is 45°-90°, the spraying distance is 100-150 mm, and the spraying speed is 600-1000 mm / s;

[0020] In step (4), the transferred arc power is 35-60 kW, the non-transferred arc power is 25-50 kW, the argon flow rate is 50-80 L / min, the hydrogen flow rate is 10-15 L / min, the wire feeding rate is 60-800 g / min, the wire-nozzle distance is 5-15 mm, the wire feeding angle is 45°-90°, the spraying distance is 100-150 mm, the spraying speed is 600-1000 mm / s, and the powder feeding rate is 20-80 g / min.

[0021] Preferably, in step (1), the nano-alumina powder and the micron-alumina powder are both spherical in shape, with a sphericity of ≥0.96, and the mass percentage of the nano-alumina powder to the micron-alumina powder is 1:1 to 1:6.

[0022] Preferably, in step (1), the modifier is a KH-560 type silane coupling agent, and the ultrasonicating time is more than 30 min.

[0023] Preferably, in step (1), the atomization pressure is 0.3-0.8 MPa and the drying temperature is 100-450℃ during spray drying.

[0024] Preferably, in step (1), the coating rate of the composite alumina powder is ≥60%.

[0025] Preferably, in step (2), the sand is brown corundum, the air pressure in sandblasting is 0.5-0.6 MPa, the sandblasting distance is 20-30 mm, and the sandblasting angle is 60-80°.

[0026] Preferably, in step (2), ultrasonic cleaning is used, the ultrasonic medium is anhydrous ethanol or acetone, and the ultrasonic time is ≥15 min.

[0027] Preferably, in steps (3) and (4), the nickel-based high-temperature alloy wire is solid core wire material with a diameter of 1.6-2.0 mm.

[0028] Preferably, in step (3), the transferred arc power is 50-60 kW, the non-transferred arc power is 18-20 kW, the wire feed rate is 100-400 g / min, and the spraying speed is 800-900 mm / s.

[0029] Preferably, in step (4), the transferred arc power is 50-60 kW, the non-transferred arc power is 30-60 kW, the wire feed rate is 100-400 g / min, the spraying speed is 800-900 mm / s, and the powder feed rate is 20-50 g / min.

[0030] Preferably, in steps (3) and (4), the transferred arc power, wire feed rate, wire-nozzle distance, spraying distance, and spraying speed are the same.

[0031] Preferably, in steps (3) and (4), the spraying path is straight-line movement, the direction of the straight-line movement includes a first direction and a second direction, the first direction is parallel to the ground, the second direction is perpendicular to the ground, the movement speed of the first direction is the same as the spraying speed, and the movement speed of the second direction is 3-5 mm / s.

[0032] Advantages

[0033] The application provides a corrosion and wear resistant thermal spraying nickel-based composite anti-skid coating, the average porosity of the coating is 1.05-2.16%, the bonding strength is 60-65 MPa, the surface Vickers hardness is 4.52-5.21 GPa, the average friction coefficient of the coating with a metal ball pair is 0.958-1.082, the wear rate is low, and the performance is excellent.

[0034] The application provides a preparation method of the corrosion and wear resistant thermal spraying nickel-based composite anti-skid coating, the transferred arc power of the preparation method is 35-60 kW, the non-transferred arc power is 15-50 kW, the nickel-based high-temperature alloy wire and the composite alumina powder are simultaneously efficiently and high-quality melted by increasing the transferred arc power and the non-transferred arc power. Meanwhile, by adjusting the power ratio of the transferred arc and the non-transferred arc and the feeding mode (separate wire feeding, wire-powder composite feeding), the plasma transferred arc wire spraying mode and the plasma transferred arc wire-powder composite spraying mode can be flexibly switched, so that the high-quality preparation of the alloy bottom layer and the metal / ceramic composite surface layer is realized respectively, and the process cost is greatly reduced. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 It is a structure schematic view of the corrosion and wear resistant nickel-based composite anti-skid coating.

[0036] Figure 2 It is a principle diagram and a spraying path of the plasma enhanced high-speed electric arc spraying and melting technology, wherein (a) is the principle diagram of the plasma enhanced high-speed electric arc spraying and melting technology, and (b) is the spraying path.

[0037] Figure 3 It is a preparation process flow diagram of the nickel-based composite anti-skid coating.

[0038] Figure 4 It is a cross-section SEM morphology diagram of the nickel-based composite anti-skid coating provided in Example 1.

[0039] Figure 5 It is a bonding strength curve of the nickel-based composite anti-skid coating provided in Example 1.

[0040] Figure 6 It is a surface micro-indentation depth-load change curve of the nickel-based composite anti-skid coating provided in Example 1.

[0041] Figure 7 It is a potentiodynamic polarization curve diagram of the nickel-based composite anti-skid coating provided in Example 1.

[0042] Figure 8 It is a surface friction coefficient change curve of the nickel-based composite anti-skid coating provided in Example 1 in a dry friction environment.

[0043] Among them, 1 is the substrate, 2 is the corrosion-resistant bottom layer, 3 is the anti-slip surface layer, 301 is nano-alumina, 302 is micron-alumina, 4 is the powder feeding channel, 5 is the metal wire, 6 is the insulating guide tube, 7 is the combined arc jet, 8 is the spray gun anode, and 9 is the tungsten cathode. Detailed Implementation

[0044] The present invention will be further described in detail below with reference to specific embodiments.

[0045] like Figure 1 As shown, the present invention provides a wear-resistant and corrosion-resistant nickel-based composite anti-slip coating, comprising, from bottom to top, a substrate 1, a corrosion-resistant underlayer 2, and an anti-slip surface layer 3.

[0046] In some embodiments, the corrosion-resistant substrate 2 is composed of a nickel-based superalloy, the elemental composition of which mainly includes Ni, Cr, Mo, and Fe, and also contains trace elements such as Nb and Al. Adding chromium can effectively improve the corrosion resistance of the alloy, thereby enhancing the service performance of the coating.

[0047] In some embodiments, the nickel-based superalloy is Inconel 625, Inconel 718, or C276.

[0048] In some embodiments, the anti-slip surface layer 3 is composed of a metallic binder phase and anti-slip ceramic particles. The metallic binder phase is a nickel-based high-temperature alloy, and its composition is consistent with that of the base layer. This reduces the difference in thermophysical properties between the corrosion-resistant base layer 2 and the anti-slip surface layer 1, thereby ensuring the overall corrosion resistance and bonding strength of the coating. The anti-slip ceramic particles in the composite surface layer 3 are composite anti-slip particles composed of nano-alumina 301 and micron-sized alumina 302. The nano-alumina 301 has a particle size of 5–100 nm, and the micron-sized alumina 302 has a particle size of 15–45 μm.

[0049] In some embodiments, the substrate 1 is a 921A or 980 alloy steel substrate, and the thickness of the substrate 1 is 5–25 mm. The present invention does not specifically limit the source of the substrate; commercially available products well known to those skilled in the art can be used.

[0050] In some embodiments, the thickness of the corrosion-resistant base layer 2 is 50-200 μm, the thickness of the anti-slip surface layer 3 is 300-600 μm, and the thickness ratio of the corrosion-resistant base layer 2 to the anti-slip surface layer 3 is 1:1 to 1:2.

[0051] In some embodiments, based on the total mass percentage of the metal binder phase, nano-alumina 301, and micron-alumina 302 in the anti-slip surface layer 3 being 100%, the metal binder phase in the anti-slip surface layer 3 is 50% to 70%, the nano-alumina 301 is 5% to 15%, and the micron-alumina 302 is 15% to 45%.

[0052] The application also provides a preparation method of the wear-resistant and corrosion-resistant nickel-based composite anti-skid coating. Figure 2 (a) Briefly introduce its technical principle:

[0053] The tungsten cathode 9 and the spray gun anode 8 form a first loop, and the metal wire 5 as a second anode forms a second loop with the tungsten cathode 9. Under the action of high-speed spraying gas, the plasma arc between the tungsten cathode 9 and the spray gun anode 8 (referred to as a non-transferred arc) can be transferred to the outside of the spray gun 8 and the metal wire 5 to form a plasma transferred arc. Under the action of the "combined arc" jet flow 7 (composed of a non-transferred arc and a transferred arc), the metal wire 5 and the ceramic powder 4 can be melted at the same time, so as to efficiently prepare a metal / ceramic composite coating on the surface of the substrate 1. When the first loop is connected and the second loop is not connected, and only powder is sent, it is supersonic plasma spraying (mode I); when the first loop and the second loop are both connected, and only the wire is sent, it is plasma transferred arc wire spraying (mode II); when the first loop and the second loop are both connected, and the wire and the powder are sent at the same time, it is plasma transferred arc wire / powder composite spraying (mode III).

[0054] A preparation method of the corrosion-resistant and wear-resistant thermal sprayed nickel-based composite anti-skid coating, the method steps comprising:

[0055] (1) adding nano-alumina powder and micron-alumina powder into a modifier solution, ultrasonicating, spray drying, sieving, to obtain composite alumina powder with a particle size of 30-60 μm;

[0056] (2) sandblasting, cleaning and drying the alloy steel substrate to obtain a treated alloy steel substrate;

[0057] (3) taking a nickel-based high-temperature alloy wire as a spraying raw material, plasma transferred arc wire spraying, to prepare a corrosion-resistant bottom layer on the treated alloy steel substrate;

[0058] (4) using nickel-based superalloy wire and composite alumina powder as the spraying raw material, plasma transferred arc wire / powder composite spraying is performed to prepare an anti-skid surface layer on the corrosion-resistant base layer;

[0059] In step (3), in order to ensure the quality of the alloy base layer and the spraying efficiency, the transferred arc power in step (3) must be 35-60 kW, and at this time the non-transferred arc only plays a role in igniting the transferred arc, so the non-transferred arc power is 15-25 kW. In addition, in order to achieve good atomization of the metal droplets after the wire is melted, the argon flow rate is 60-100 L / min, and the hydrogen flow rate is 8-10 L / min. Other parameters meet the following requirements: the wire feeding rate is 60-800 g / min, the wire-nozzle distance is 5-15 mm, the wire feeding angle is 45°-90°, the spraying distance is 100-150 mm, and the spraying speed is 600-1000 mm / s.

[0060] In step (4), the transferred arc power is 35-60 kW, the non-transferred arc power is 25-50 kW, the wire feeding rate is 60-800 g / min, the wire-nozzle distance is 5-15 mm, the wire feeding angle is 45°-90°, the spraying distance is 100-150 mm, the spraying speed is 600-1000 mm / s, and the powder feeding flow rate is preferably 20-80 g / min. Too high a gas flow rate will weaken the heating effect of the ceramic powder, causing it to be unable to melt, so the argon flow rate needs to be reduced to 50-80 L / min, and the hydrogen flow rate can be appropriately increased to 10-15 L / min to increase the non-transferred arc power, and the powder feeding gas flow rate is 5-15 L / min.

[0061] In some embodiments, in step (1), the nano-alumina powder and the micro-alumina powder are both spherical in shape, with a sphericity of ≥0.96, and the mass percentage of the nano-alumina powder to the micro-alumina powder is 1:1-1:6.

[0062] In some embodiments, in step (1), the modifier is a KH-560 type silane coupling agent, and the ultrasonic time is more than 30 min.

[0063] In some embodiments, in step (1), when spray drying, the atomization pressure is 0.3-0.8 MPa, and the drying temperature is 100-450°C. A pressure spraying granulation device is used, the slurry is sprayed into the drying chamber to be atomized, the droplets are quickly dried in the hot air, and a composite coated structure powder of nano-coated micro-alumina is formed.

[0064] In some embodiments, in step (1), the coating rate of the composite alumina powder is ≥60%.

[0065] In some embodiments, in step (2), the sand particles are brown corundum, the air pressure in the sand blasting is 0.5-0.6 MPa, the sand blasting distance is 20-30 mm, and the sand blasting angle is 60-80°.

[0066] In some embodiments, in step (2), the ultrasonic cleaning is used in the cleaning, the ultrasonic medium is anhydrous ethanol or acetone, and the ultrasonic time is more than 15 min.

[0067] In some embodiments, in steps (3) and (4), the nickel-based superalloy wire is a solid core wire with a diameter of 1.6-2.0 mm.

[0068] In some embodiments, in step (3), the transferred arc power is 50-60 kW, the non-transferred arc power is 18-20 kW, the wire feeding amount is 100-400 g / min, and the spraying speed is 800-900 mm / s.

[0069] In some embodiments, in step (4), the transferred arc power is 50-60 kW, the non-transferred arc power is 30-60 kW, the wire feeding amount is 100-400 g / min, the spraying speed is 800-900 mm / s, and the powder feeding amount is 20-50 g / min.

[0070] In some embodiments, in steps (3) and (4), the transferred arc power, the wire feeding amount, the wire-nozzle distance, the spraying distance, and the spraying speed are the same.

[0071] In some embodiments, in steps (3) and (4), the spraying path is a straight line movement, the direction of the straight line movement includes a first direction and a second direction, the first direction is parallel to the ground, the second direction is perpendicular to the ground, the movement speed of the first direction is the same as the spraying speed, and the movement speed of the second direction is 3-5 mm / s.

[0072] The preparation method of the wear-resistant and corrosion-resistant nickel-based composite anti-skid coating will be described in detail below with reference to the embodiments, and the microstructure and service performance of the coating are comprehensively characterized. As shown in FIG. 1, the process flow diagram of the preparation of the nickel-based composite anti-skid coating by the plasma-enhanced high-speed electric arc spraying and melting technology is shown. Figure 3

[0073] Embodiment 1

[0074] ​(1) Powder preparation: spherical nano-alumina powder with a particle size distribution of 50-100 nm and micron alumina powder with a particle size distribution of 15-45 μm were weighed according to a mass ratio of 1:2, then added into a KH-560 type silane coupling agent solution, and ultrasonically modified for 30 min. Then, a spray drying process was used to coat the powder, forming spherical micro / nano composite alumina powder. Finally, a powder sifter was used to sift out micro / nano composite alumina powder with a particle size of 30-60 μm as the spray powder.

[0075] (2) Pretreatment: 921A steel plate was selected as the metal substrate for spraying, and the substrate size was 100x10x5 (mm) for testing various performance indicators of the coating. The substrate surface should be kept flat, without processing marks and rust marks; the metal substrate surface was sequentially sandblasted, ultrasonically cleaned and dried. The sandblasting sand was brown corundum (main component: AI2O3), the air pressure in the sandblasting was 0.5 MPa, the sandblasting distance was 20 mm, and the sandblasting angle was 80°. The ultrasonic cleaning medium was anhydrous ethanol, and the ultrasonic cleaning time was 15 min.

[0076] (3) Corrosion-resistant bottom layer spraying: Inconel 625 alloy solid wire was selected as the raw material for spraying, and the diameter of the wire was 1.6 mm; mode II-plasma transferred arc wire spraying was selected to prepare the corrosion-resistant bottom layer, and the spraying process parameters were adjusted, the wire feed rate was 250 g / min, the wire-nozzle distance was 10 mm, the wire feed angle was 90°, the non-transferred arc power was 15 kW, the transferred arc power was 60 kW, the argon flow rate was 100 L / min, the hydrogen flow rate was 8 L / min, the spraying distance was 120 mm, and the spraying speed was 800 mm / s. Subsequently, as shown in Figure 2 (b), the spraying route was set, the spraying path was linear movement, and the first direction was parallel to the ground, the movement displacement d x of the first direction was 120 mm, the second direction was perpendicular to the ground, the movement displacement d y of the second direction was 3 mm, the total displacement Y of the second direction was 100 mm, the movement speed of the first direction was the same as the spraying speed, which was 800 mm / s, and the movement speed of the second direction was 4 mm / s. According to the spraying path shown in Figure 2 (b), spraying was performed once.

[0077] (4) Anti-skid surface layer spraying: Inconel 625 alloy solid core wire with a diameter of 1.6 mm and micro / nano composite alumina powder with a particle size of 30-60 μm are selected as raw materials for spraying; mode III-plasma transferred arc wire / powder composite spraying is selected to prepare the anti-skid surface layer, and the spraying process parameters are adjusted, wherein the wire feeding amount is 250 g / min, the powder feeding amount is 30 g / min, the powder feeding gas flow is 8 L / min, the wire-nozzle distance is 10 mm, the wire feeding angle is 90°, the non-transferred arc power is 30 kW, the transferred arc power is 60 kW, the argon flow is 60 L / min, the hydrogen flow is 15 L / min, the spraying distance is 120 mm, and the spraying speed is 800 mm / s. The spraying path is the same as that in step three, and spraying is performed once.

[0078] (5) Post-processing: after spraying, the coating is naturally cooled to room temperature at normal temperature and pressure.

[0079] Figure 4 is a cross-sectional SEM morphology diagram of the composite anti-skid coating described in the present embodiment. As can be seen from Figure 4 , the structure of the composite coating is sequentially the substrate, the corrosion-resistant bottom layer and the anti-skid surface layer from bottom to top, which is consistent with the structure diagram of the nickel-based composite anti-skid coating provided by the present application ( Figure 1 ). The results show that the average thickness of the corrosion-resistant bottom layer is about 100 μm, and the structure is dense without obvious pores, cracks and other defects; the average thickness of the anti-skid surface layer is about 150 μm, wherein the smaller size black phase is nano alumina, and the larger size black phase is micron alumina.

[0080] The porosity of the composite coating is tested by using Image J software, and the repeated test is at least ≥3 times, and the results are shown in Table 1, and the average porosity is about 1.32%, indicating that the microstructure of the coating is excellent.

[0081] Table 1 Average porosity of the nickel-based composite anti-skid coating of Example 1

[0082] Composite coating Porosity-1 0.89％ Porosity-2 1.05％ Porosity-3 2.03％ Average porosity 1.32％

[0083] Figure 5 is a bonding strength curve of the composite anti-skid coating described in the present embodiment. As can be seen from Figure 5 , the nickel-based composite anti-skid coating provided by the present application has a relatively high bonding strength, and the average bonding strength is about 65 MPa.

[0084] Figure 6The surface micro-indentation depth-load curve of the composite anti-skid coating was obtained. The hardness of the coating cross-section was tested by a micro-Vickers hardness tester, the load was 200 g, and 5 points on the surface of the coating were selected for testing. The average values of the hardness and elastic modulus of the coating were calculated according to the depth-load curve, and the results are shown in Table 2, indicating that the coating has excellent mechanical properties.

[0085] Table 2 Mechanical property parameters of the nickel-based composite anti-skid coating of Example 1

[0086] Mechanical property parameters Composite coating Average hardness / GPa 4.52 Average elastic modulus / GPa 155.98

[0087] Figure 7 The potentiodynamic polarization curve of the composite anti-skid coating was obtained. The corrosion resistance of the nickel-based composite anti-skid coating was evaluated by a CHI760E electrochemical workstation, the test temperature was room temperature 25℃, the corrosion medium was 3.5% NaCl solution, and the working surface area of the coating was 1 cm 2 , wherein the working electrode was the coating sample, the reference electrode was a saturated calomel electrode, the auxiliary electrode was a platinum electrode, the scanning interval was -100 mV-1500 mV, and the scanning rate was 0.5 mV / s. The results are shown in Table 3, the self-corrosion potential of the coating is about 0.857 V, and the self-corrosion current density is about 10.690×10 - 6 A·cm -2 , it can be seen that there is a clear passivation interval, indicating that the passivation performance of the composite coating is excellent, which improves the corrosion resistance of the coating to some extent. Figure 7

[0088] Table 3 Electrochemical parameters of the nickel-based composite anti-skid coating of Example 1

[0089] Self-corrosion potential / V Self-corrosion current density A cm -2 ]] Composite coating -0.857 10.690 x 10 -6 ]]

[0090] Figure 8 The surface friction coefficient curve of the nickel-based composite anti-skid coating in a dry friction environment was obtained. The friction coefficient of the coating was tested by a Bruker UMT-TriboLab multifunctional friction and wear tester, the friction pair was in the form of dry friction, the reciprocating ball-disc type, the counter-attrition pair was a GCr15 metal ball with a diameter of 10 mm, the reciprocating frequency was 5 Hz, the reciprocating distance was 5 mm, the load was 30 N, the test time was 30 min, at least 3 repeated groups were set, and the average value was calculated as the friction coefficient of the coating. The results are shown in Table 4. Figure 8 ​Representative friction coefficient curve of the coating is given. The friction coefficient of the composite coating is about 1.028, which can be kept stable for a long time, indicating that the coating has excellent anti-skid performance. Subsequently, the surface of the worn coating is measured by KLA Tencor-MicroXAM white light interferometer, and the wear rate of the coating is about 3.21 x 10 -14 m 3 / Nm, and the results are shown in Table 5.

[0091] Table 4 Friction coefficient of nickel-based composite anti-skid coating of Example 1

[0092] Composite coating Friction coefficient-1 1.121 Friction coefficient-2 0.971 Friction coefficient-3 0.992 Average friction coefficient 1.028

[0093] Table 5 Wear rate of nickel-based composite anti-skid coating of Example 1

[0094] Composite coating Wear rate-1 2.79 x 10 -14 m 3 / Nm]]> Wear rate-2 3.88 x 10 -14 m 3 / Nm]]> Wear rate-3 2.95 x 10 -14 m 3 / Nm]]> Average wear rate 3.21 x 10 -14 m 3 / Nm]]>

[0095] Example 2

[0096] The other steps are the same as those in Example 1, except that:

[0097] The mass fraction ratio of the nano-alumina powder to the micron-alumina powder in step (1) is changed to 1:6.

[0098] In step (3), the wire is changed to Inconel 718 solid core alloy wire with a diameter of 2.0 mm, the wire feeding amount is changed to 350 g / min, and the hydrogen flow is changed to 10 L / min.

[0099] In step (4), the wire is also changed to Inconel 718 solid core alloy wire with a diameter of 2.0 mm, the wire feeding amount is changed to 350 g / min, the wire feeding angle is changed to 65°, the powder feeding amount is changed to 50 g / min, the non-transferred arc power is changed to 30 kW, the transferred arc power is changed to 55 kW, the argon flow is 80 L / min, and the hydrogen flow is 12 L / min.

[0100] Subsequently, according to the performance test method in Example 1, the performance indicators of the nickel-based composite anti-skid coating in Example 2 are tested.

[0101] Table 6 The average porosity of the coating in Example 2 is about 0.96%, indicating that the microstructure of the composite coating is improved as the powder particle size decreases.

[0102] Table 6 Average porosity of nickel-based composite anti-skid coating of Example 2

[0103] Composite coating Porosity-1 0.76％ Porosity-2 1.12％ Porosity-3 0.99％ Average porosity 0.96％

[0104] Table 7 shows that the average bonding strength of the coating in Example 2 is about 69.0 MPa, indicating that as the porosity of the coating decreases, the bonding strength also increases.

[0105] Table 7 shows the average bonding strength of the nickel-based composite non-slip coating in Example 2

[0106] Composite coating Bond strength-1 72.3 MPa Bond strength-2 65.8 MPa Bond strength-3 68.9 MPa Average bond strength 69.0 MPa

[0107] Table 8 shows the average hardness and average elastic modulus of the coating in Example 2, which are 5.52 GPa and 163.97 GPa, respectively. The mechanical properties of the coating are closely related to the defect rate and uniformity of its structure. When the porosity of the coating decreases, the mechanical properties are also significantly improved.

[0108] Table 8 shows the mechanical property parameters of the nickel-based composite non-slip coating in Example 2

[0109] Mechanical property parameters Composite coating Average hardness / GPa 5.52 Average elastic modulus / GPa 163.97

[0110] Table 9 shows the electrochemical performance parameters of the coating in Example 2, with a self-corrosion potential of about 0.633 V and a self-corrosion current density of about 6.542 x 10 -6 A·cm -2 The results show that the Inconel 718 composite non-slip coating has more excellent corrosion resistance than the Inconel 625 composite coating.

[0111] Table 9 shows the electrochemical parameters of the nickel-based composite non-slip coating in Example 1

[0112] Self-corrosion potential / V Self-corrosion current density A cm -2 ]] Composite coating -0.633 6.542 x 10 -6 ]]>

[0113] Table 10 and Table 11 show the average friction coefficient and wear rate of the coating in Example 2, with an average friction coefficient of about 0.952 and an average wear rate of 2.71 x 10 -14 m 3 / Nm. The results show that as the particle size of the ceramic powder decreases, the friction coefficient of the coating also decreases, but remains at a relatively high level. The surface non-slip performance of the coating is still excellent. At the same time, the wear rate of the coating slightly decreases, indicating that the wear resistance of the composite coating improves as the particle size decreases.

[0114] Table 10 shows the friction coefficient of the nickel-based composite non-slip coating in Example 2

[0115] Composite coating Friction coefficient-1 0.895 Friction coefficient-2 1.003 Friction coefficient-3 0.958 Average friction coefficient 0.952

[0116] Table 11 shows the wear rate of the nickel-based composite non-slip coating in Example 2

[0117] Composite coating Wear rate-1 2.65 x 10 -14 m 3 / Nm]]> Wear rate-2 3.13 x 10 -14 m 3 / Nm]]> Wear rate-3 2.35 x 10 -14 m 3 / Nm]]> Average wear rate 2.71 x 10 -14 m 3 / Nm]]>

[0118] In conclusion, the invention includes but is not limited to the embodiments described above, any equivalents thereto or modifications made thereon, which come within the scope of the invention as defined by the following claims.

Claims

1. A method of producing a corrosion and wear resistant thermal sprayed nickel-based composite non-skid coating, characterized by: The method steps comprise: (1) adding nano-alumina powder and micro-alumina powder into a modifier solution, ultrasonicating, spray drying, sieving, to obtain composite alumina powder with a particle size of 30-60 μm; (2) sandblasting, cleaning and drying the alloy steel substrate to obtain a treated alloy steel substrate; (3) using a nickel-based high-temperature alloy wire as a spraying raw material, performing plasma transferred arc wire spraying to prepare a corrosion-resistant bottom layer on the treated alloy steel substrate; (4) using a nickel-based high-temperature alloy wire and composite alumina powder as spraying raw materials, performing plasma transferred arc wire / powder composite spraying to prepare an anti-skid surface layer on the corrosion-resistant bottom layer; In step (3), the transferred arc power is 35-60 kW, the non-transferred arc power is 15-25 kW, the argon flow rate is 60-100 L / min, the hydrogen flow rate is 8-10 L / min, the wire feeding rate is 60-800 g / min, the wire-nozzle distance is 5-15 mm, the wire feeding angle is 45°-90°, the spraying distance is 100-150 mm, and the spraying speed is 600-1000 mm / s; In step (4), the transferred arc power is 35-60 kW, the non-transferred arc power is 25-50 kW, the flow rate is 50-80 L / min, the hydrogen flow rate is 10-15 L / min, the wire feeding rate is 60-800 g / min, the wire-nozzle distance is 5-15 mm, the wire feeding angle is 45°-90°, the spraying distance is 100-150 mm, the spraying speed is 600-1000 mm / s, and the powder feeding rate is 20-80 g / min; The composite anti-skid coating comprises, from bottom to top, an alloy steel substrate, a corrosion-resistant bottom layer and an anti-skid surface layer; the corrosion-resistant bottom layer is a nickel-based high-temperature alloy, the chemical composition of the nickel-based high-temperature alloy comprises Ni, Cr, Mo, Fe, Nb and Al, the thickness of the corrosion-resistant bottom layer is 50-200 μm; the anti-skid surface layer is composed of the same nickel-based high-temperature alloy, nano-alumina particles and micro-alumina particles as the corrosion-resistant bottom layer, the mass fraction of the nickel-based high-temperature alloy is 50%-70%, the mass fraction of the nano-alumina particles is 5%-15%, the mass fraction of the micro-alumina particles is 15%-45%, and the thickness of the anti-skid surface layer is 300-600 μm.

2. A process for the production of a corrosion and wear resistant thermal sprayed nickel based composite non-skid coating as claimed in claim 1, wherein: The alloy steel substrate is 921A alloy steel or 980 alloy steel; The mass percentage of the chemical composition of the alloy is, based on the total mass of the nickel-based high-temperature alloy being 100%, Ni is 50%-58%, Cr is 12%-25%, Mo is 2%-15%, Fe is 5%-15%, Nb is 3.0%-4.0%, Al≤0.4%, and the balance is Ni and unavoidable impurity elements.

3. A process for the production of a corrosion and wear resistant thermal sprayed nickel based composite non-skid coating as claimed in claim 2, wherein: The nickel-based high-temperature alloy is Inconel 625 alloy, Inconel 718 alloy or C276 alloy.

4. A process for the production of a corrosion and wear resistant thermal sprayed nickel based composite non-skid coating as claimed in claim 1 wherein: The particle size of the nano-alumina particles is 5-100 nm, and the particle size of the micro-alumina particles is 15-45 μm.

5. A method of producing a corrosion and wear resistant thermal sprayed nickel-based composite non-skid coating as claimed in claim 1, wherein: The thickness ratio of the corrosion-resistant base layer and the anti-skid surface layer is 1:1 to 1:

2.

6. A method of producing a corrosion and wear resistant thermal sprayed nickel-based composite non-skid coating as claimed in claim 1, wherein: In step (1), the nano-alumina powder and the micro-alumina powder are both spherical in shape, with a sphericity of greater than or equal to 0.96, and the mass percentage of the nano-alumina powder to the micro-alumina powder is 1:1 to 1:6; The modifier is a KH-560 type silane coupling agent, and the ultrasonic time is more than 30 min; In the spray drying, the atomization pressure is 0.3 to 0.8 MPa, and the drying temperature is 100 to 450 DEG C. The coating rate of the composite alumina powder is greater than or equal to 60%.

7. A method of producing a corrosion and wear resistant thermal sprayed nickel-based composite non-skid coating as claimed in claim 1 wherein: In step (2), the sand particles are brown corundum, the air pressure in the sandblasting is 0.5 to 0.6 MPa, the sandblasting distance is 20 to 30 mm, and the sandblasting angle is 60 to 80 DEG; In the cleaning, ultrasonic cleaning is adopted, the ultrasonic medium is anhydrous ethanol or acetone, and the ultrasonic time is more than 15 min.

8. A method of producing a corrosion and wear resistant thermal sprayed nickel-based composite non-skid coating as claimed in claim 1, wherein: In steps (3) and (4), the nickel-based high-temperature alloy wire is a solid core wire material, and the diameter is 1.6 to 2.0 mm; In step (3), the transferred arc power is 50 to 60 kW, the non-transferred arc power is 18 to 20 kW, the wire feeding amount is 100 to 400 g / min, and the spraying speed is 800 to 900 mm / s; In step (4), the transferred arc power is 50 to 60 kW, the non-transferred arc power is 30 to 60 kW, the wire feeding amount is 100 to 400 g / min, the spraying speed is 800 to 900 mm / s, and the powder feeding amount is 20 to 50 g / min.

9. A method of producing a corrosion and wear resistant thermal sprayed nickel-based composite non-skid coating as claimed in claim 1, wherein: In steps (3) and (4), the transferred arc power, the wire feeding amount, the wire-nozzle distance, the spraying distance and the spraying speed are the same. In steps (3) and (4), the spraying path is straight-line movement, the direction of the straight-line movement includes a first direction and a second direction, the first direction is parallel to the ground, the second direction is perpendicular to the ground, the movement speed of the first direction is the same as the spraying speed, and the movement speed of the second direction is 3 to 5 mm / s.

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