A zirconium-based amorphous alloy-titanium alloy composite coating and a preparation method thereof

Abstract

The application discloses a zirconium-based amorphous alloy-titanium alloy composite coating and a preparation method thereof, and belongs to the technical field of preparation of wear-resistant and corrosion-resistant materials.The preparation method comprises the following steps: (1) pretreating a substrate; (2) performing layer-by-layer cladding on the substrate by adopting a laser cladding process to form a gradient-coupled titanium alloy layer; and (3) layer-by-layer spraying a zirconium-based amorphous alloy coating on the surface of the titanium alloy layer by adopting a high-velocity oxygen fuel spraying technology.The load material coating with the gradient structure of the crystal and the amorphous crystal is prepared by adopting the preparation method, so that the titanium alloy layer and the zirconium-based amorphous alloy layer have high interface bonding strength, and the composite coating with more comprehensive performance and excellent performance is obtained.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of wear-resistant and corrosion-resistant material preparation, and relates to a zirconium-based amorphous alloy-titanium alloy composite coating and a preparation method thereof. BACKGROUND

[0002] The coating is coated on a metal, fabric, plastic or other substrate to achieve protection, insulation, decoration and other purposes of the substrate, and the protection is the most common function of the coating, and the protection function of the coating is mainly realized through the performance of the coating itself.

[0003] In order to make the substrate obtain better protection effect and be more widely applied, the coating itself needs to have more excellent and comprehensive performance. Titanium alloy is widely used in aerospace, marine equipment, petroleum and chemical industry, medical devices and other fields due to its high specific strength, fatigue resistance, low density, low thermal expansion coefficient and other excellent characteristics. However, titanium alloy has problems of low material hardness, poor corrosion resistance and poor wear resistance, which limits its protection to the substrate as a coating.

[0004] Therefore, it is necessary to provide a zirconium-based amorphous alloy-titanium alloy composite coating to improve the hardness, corrosion resistance and wear resistance of the coating. SUMMARY

[0005] In order to overcome the problems in the background art, the application provides a zirconium-based amorphous alloy-titanium alloy composite coating and a preparation method thereof. The prepared zirconium-based amorphous alloy-titanium alloy composite coating has a gradient structure coupled with crystal and amorphous phase, so that the coating has high hardness, good corrosion resistance and wear resistance.

[0006] In order to achieve the above purpose, the application is realized by the following technical scheme:

[0007] A preparation method of a zirconium-based amorphous alloy-titanium alloy composite coating, comprising the following steps:

[0008] (1) Pre-treating the substrate, including surface grinding or sand blasting treatment of the substrate, and then cleaning and drying the substrate.

[0009] (2) Layered cladding on the substrate by laser cladding process to form a gradient coupled titanium alloy layer, and then processing and finishing the titanium alloy layer and cleaning and drying.

[0010] (3) Layered spraying of zirconium-based amorphous alloy coating on the surface of the titanium alloy layer by using supersonic flame spraying technology, and after post-treatment of the surface, a composite coating with a gradient structure is obtained. The flame speed of the supersonic flame spraying technology is very fast, but the temperature is relatively low, which avoids the crystallization phenomenon of amorphous caused by too high temperature.

[0011] As preferred, the step (1) adopts mechanical polishing to polish the surface of the substrate, and the roughness Ra is less than 0.5, then the substrate is ultrasonically cleaned with alcohol and dried.

[0012] As preferred, the step (1) adopts corundum sand blasting to remove surface contaminants, and the roughness Ra of the processed surface is 8.0-10.0, then the substrate is ultrasonically cleaned with alcohol and dried.

[0013] As preferred, the step (2) includes the following steps: first, Ti powder is used as raw material to form a Ti layer with a thickness of 50-150 μm; second, Ti and Al powders with equal molar ratio are used as raw material to form a Ti and Al layer with a thickness of 50-150 μm; and finally, Al, V and Ti powders with equal molar ratio are used as raw material to form a Ti, Al and V layer with a thickness of 50-150 μm, thereby obtaining a gradient-coupled titanium alloy layer with a total thickness of 300-350 μm. The raw material powder is uniformly coated on the surface of the substrate by a powder feeding system; a high-energy laser beam is used to irradiate the coating to rapidly melt the coating and form a molten pool; after the laser irradiation, the coating is rapidly cooled and solidified; and the coating is formed into a dense gradient-structured titanium alloy layer through multiple cladding.

[0014] As preferred, the step (3) includes the following steps: first, Zr, Ti and Cu powders with equal molar ratio are used as raw material to form a Zr, Ti and Cu amorphous layer with a thickness of 100-150 μm; second, Zr, Ti, Cu and Ni powders with equal molar ratio are used as raw material to form a Zr, Ti, Cu and Ni amorphous layer with a thickness of 100-150 μm; and finally, Zr, Ti, Cu, Ni and Be powders with equal molar ratio are used as raw material to form a Zr, Ti, Cu, Ni and Be amorphous layer with a thickness of 100-150 μm, thereby obtaining a zirconium-based amorphous alloy coating with a total thickness of 300-350 μm.

[0015] As preferred, the powder particle size is 10-60 μm; the laser cladding powder feeding speed is 20-40 g / min; the laser cladding laser beam scanning speed is 60-120 m / min; the laser cladding laser beam emission power is 1-2 kW; and the laser cladding laser beam spot diameter is 1-3 mm.

[0016] As preferred, the step (2) adopts corundum sand blasting to process and trim the titanium alloy layer, and the roughness Ra of the processed titanium alloy layer is 6.0-12.0, then the titanium alloy layer is ultrasonically cleaned with alcohol and dried.

[0017] As preferred, the powder particle size is 15-45 mu m, the spraying distance is 350-380 mm, the spraying speed is 250-350 mm / s, the spraying powder flow is 45-60 g / min, the spraying oxygen flow is 40-50 m 3 / h, and the spraying kerosene flow is 20-25 L / h.

[0018] As preferred, the post-treatment of the surface in step (3) specifically includes: trimming the surface rough part, removing the excess spraying material, to ensure the surface smooth and reach the required accuracy requirement, and the surface roughness of the treated zirconium-based amorphous alloy coating is Ra=0.2-0.8.

[0019] The zirconium-based amorphous alloy-titanium alloy composite coating prepared by the preparation method of the zirconium-based amorphous alloy-titanium alloy composite coating has a gradient structure of crystal and amorphous coupling.

[0020] The present application has the following beneficial effects:

[0021] 1. The present application prepares a zirconium-based amorphous alloy-titanium alloy composite coating with a gradient structure of crystal and amorphous coupling, which makes up for the problems of low hardness, poor wear resistance and poor corrosion resistance of titanium alloy, so that the coating has more comprehensive performance and improves the protection effect of the coating.

[0022] 2. The present application prepares a titanium alloy coating with element gradient by laser cladding technology, so that the titanium alloy coating can better adhere to the surface of the substrate.

[0023] 3. The present application sprays a zirconium-based amorphous alloy coating with a gradient structure by supersonic flame spraying technology, and the prepared coating is clean, dense, fine and uniform, and is closely combined with the titanium alloy coating. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 It is a schematic diagram of the zirconium-based amorphous coating and the titanium alloy layer in the examples.

[0025] Figure 2 It is an electrochemical corrosion experiment curve of the coating in Example 1. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and beneficial effects of the present application clearer, the present application will be further described in detail below with specific examples.

[0027] The examples and comparative examples of the present application all use 316L stainless steel as the substrate material for experiments.

[0028] Example 1

[0029] (1) First, the substrate surface is mechanically polished to flatten the substrate surface, with a roughness Ra = 0.3, and then the substrate is ultrasonically cleaned with alcohol and dried.

[0030] (2) Layered cladding is performed on the substrate using a laser cladding process. First, Ti powder is used as the raw material to form a 100 μm Ti layer, then equal-molar Ti and Al powders are used as the raw material to form a 100 μm Ti and Al layer, and finally equal-molar Al, V, and Ti powders are used as the raw material to form a 100 μm Ti, Al, and V layer. In the cladding process, the powder particle size is 10 μm, the powder feed rate is 30 g / min, the laser beam scanning speed is 100 m / min, the laser beam emission power is 2 kW, and the laser beam spot diameter is 2 mm. After multiple cladding, a gradient-coupled titanium alloy layer with a total thickness of 300 μm is obtained. The titanium alloy layer is treated with corundum sandblasting, and the surface roughness of the treated titanium alloy layer is Ra = 10.0. Then, the titanium alloy layer is ultrasonically cleaned with alcohol and dried.

[0031] (3) A wear-resistant and corrosion-resistant zirconium-based amorphous coating is prepared on the titanium alloy layer using a high-velocity oxygen fuel spraying technique. First, equal-molar Zr, Ti, and Cu are used as the raw material to form a 100 μm Zr, Ti, and Cu amorphous layer; then equal-molar Zr, Ti, Cu, and Ni are used as the raw material to form a 100 μm Zr, Ti, Cu, and Ni amorphous layer; and finally equal-molar Zr, Ti, Cu, Ni, and Be are used as the raw material to form a 100 μm Zr, Ti, Cu, Ni, and Be amorphous layer. During spraying, the powder particle size is 15 μm, the oxygen flow rate is 40 m 3 / h, the kerosene flow rate is 20 L / h, the powder feed rate is 45 g / min, the spraying distance is 350 mm, the spraying speed is 300 m / s, and after multiple spraying, the coating thickness is 300 μm. The surface is post-treated to trim the rough surface and remove excess sprayed material, and the treated surface roughness is Ra = 0.2. A composite coating with a gradient structure is prepared.

[0032] Example 2

[0033] (1) First, the substrate surface is mechanically polished to flatten the substrate surface, with a roughness Ra = 0.3, and then the substrate is ultrasonically cleaned with alcohol and dried.

[0034] (2) Laser cladding process is used to perform layer-by-layer cladding on the substrate. First, Ti powder is used as raw material to form a 150 μm Ti layer. Second, Ti and Al powders with equal molar ratio are used as raw material to form a 150 μm Ti and Al layer. Finally, Al, V and Ti powders with equal molar ratio are used as raw material to form a 50 μm Ti, Al and V layer. In the cladding process, the powder particle size is 35 μm, the powder feeding speed is 40 g / min, the laser beam scanning speed is 120 m / min, the laser beam emission power is 1.5 kW, and the laser beam spot diameter is 3 mm. After multiple cladding, a gradient-coupled titanium alloy layer with a total thickness of 350 μm is obtained. The titanium alloy layer is treated by corundum sandblasting, and the surface roughness of the treated titanium alloy layer is Ra=6.0. Then, the titanium alloy layer is cleaned and dried by ultrasonic cleaning with alcohol.

[0035] (3) A wear-resistant and corrosion-resistant zirconium-based amorphous coating is prepared on the titanium alloy layer by using a high-velocity oxygen fuel spraying technology. First, Zr, Ti and Cu powders with equal molar ratio are used as raw material to form a 50 μm Zr, Ti and Cu amorphous layer. Second, Zr, Ti, Cu and Ni powders with equal molar ratio are used as raw material to form a 150 μm Zr, Ti, Cu and Ni amorphous layer. Finally, Zr, Ti, Cu, Ni and Be powders with equal molar ratio are used as raw material to form a 150 μm Zr, Ti, Cu, Ni and Be amorphous layer. In the spraying process, the powder particle size is 30 μm, the oxygen flow rate is 45 m 3 / h, the kerosene flow rate is 25 L / h, the powder feeding rate is 60 g / min, the spraying distance is 380 mm, and the spraying speed is 350 m / s. After multiple spraying, the coating thickness is 350 μm. The surface is post-treated to trim the surface roughness and remove excess sprayed material. The surface roughness after treatment is Ra=0.8, and a composite coating with a gradient structure is prepared.

[0036] Example 3

[0037] (1) First, the substrate surface is treated by corundum sandblasting to remove surface contaminants. The surface roughness after treatment is Ra=10.0. Then, the substrate is cleaned and dried by ultrasonic cleaning with alcohol.

[0038] (2) Laser cladding process is used to perform layer-by-layer cladding on the substrate. First, Ti powder is used as raw material to form a 50 μm Ti layer. Second, Ti and Al powders with equal molar ratio are used as raw material to form a 125 μm Ti and Al layer. Finally, Al, V and Ti powders with equal molar ratio are used as raw material to form a 150 μm Ti, Al and V layer. In the cladding process, the powder particle size is 60 μm, the powder feeding speed is 20 g / min, the laser beam scanning speed is 60 m / min, the laser beam emission power is 1 kW, and the laser beam spot diameter is 1 mm. After multiple cladding, a gradient-coupled titanium alloy layer with a total thickness of 325 μm is obtained. Corundum sand blasting is used to treat the titanium alloy layer, and the surface roughness after treatment is Ra = 12.0. Then, the titanium alloy layer is cleaned and dried by ultrasonic cleaning with alcohol.

[0039] (3) A zirconium-based amorphous coating with wear resistance and corrosion resistance is prepared on the titanium alloy layer by using high-velocity oxygen fuel spraying technology. First, Zr, Ti and Cu powders with equal molar ratio are used as raw material to form a 50 μm Zr, Ti and Cu amorphous layer. Second, Zr, Ti, Cu and Ni powders with equal molar ratio are used as raw material to form a 125 μm Zr, Ti, Cu and Ni amorphous layer. Finally, Zr, Ti, Cu, Ni and Be powders with equal molar ratio are used as raw material to form a 150 μm Zr, Ti, Cu, Ni and Be amorphous layer. In the spraying process, the powder particle size is 45 μm, the oxygen flow rate is 50 m 3 / h, the kerosene flow rate is 23 L / h, the powder feeding rate is 50 g / min, the spraying distance is 370 mm, and the spraying speed is 250 m / s. After multiple spraying, the coating thickness is 325 μm. The surface is treated to trim the rough surface and remove the excess sprayed material. The surface roughness after treatment is Ra = 0.5, and a composite coating with gradient structure is prepared.

[0040] Example 4

[0041] In this example, the method for preparing the composite coating is the same as that in Example 1, except that in this example, the substrate is treated by corundum sand blasting to remove surface contaminants, and the surface roughness after treatment is Ra = 9.0.

[0042] Comparative Example 1

[0043] In this comparative example, the method for preparing the composite coating is the same as that in Example 1, except that in this comparative example, the titanium alloy coating and the zirconium-based amorphous alloy coating are both non-gradient structures. Al, V and Ti powders with equal molar ratio are used as raw material to form the titanium alloy layer, and Zr, Ti, Cu, Ni and Be powders are used as raw material to form the zirconium-based amorphous alloy coating.

[0044] Comparative Example 2

[0045] The method for preparing the composite material coating in this comparative example is the same as that in Example 1, except that in this comparative example, only a titanium alloy coating with a gradient structure is fused onto the substrate.

[0046] Comparative Example 3

[0047] The method for preparing the composite material coating in this comparative example is the same as that in Example 1, except that: in this comparative example, only a zirconium-based amorphous alloy coating with a gradient structure is sprayed onto the substrate.

[0048] Porosity analysis of the coatings prepared in Examples 1-4 was performed using image analysis to evaluate coating density. Five SEM images of the cross-section of the coatings prepared in the examples were calculated and averaged. It was found that the zirconium-based amorphous alloy-titanium alloy composite coating has good bonding with the substrate, the coating porosity is only 1%, and there are no large pores and the density is high in the zirconium-based amorphous alloy coating.

[0049] The coatings prepared in the examples and comparative examples were subjected to microhardness tests using a digital Vickers microhardness tester. The test force was 0.98 N and the load time was 10 s. Ten areas were randomly selected for measurement, and the average hardness value was taken, as shown in Table 1.

[0050] The bonding strength of the coatings prepared in the examples and comparative examples was tested. The bonding strength between the zirconium-based amorphous alloy coating and the titanium alloy coating was determined using an electronic universal testing machine. Commercial FM1000 adhesive was used to bond the coating surface and the loading fixture. The test speed was set to 0.021 mm / s, the maximum applied load was recorded, and the bonding strength was calculated. See Table 1.

[0051] The coatings prepared in the examples and comparative examples were subjected to corrosion resistance electrochemical tests. The corrosion tests were conducted using an electrochemical workstation with 50% H2SO4 as the corrosion solution. The corrosion rate was calculated by testing the polarization curves of the substrate and the coating, as shown in Table 1.

[0052] Wear resistance tests were conducted on the coatings prepared in the examples and comparative examples. The coatings were tested using a reciprocating friction and wear tester. The friction pair consisted of a steel ball with a diameter of 6 mm, a load of 50 N, a friction rate of 3 mm / s, a sliding length of 3 mm, and a sliding time of 60 min. The test results are shown in Table 1.

[0053] Table 1

[0054]

[0055] As shown in Table 1, the bonding strength, hardness, and other properties of the coatings in Examples 1-3 are all higher than those in Comparative Examples 1-3, with significant improvements. The comparison demonstrates that the coatings in Examples 1-3 of this invention exhibit excellent overall mechanical properties.

[0056] The laser cladding titanium alloy layer in Examples 1-3 transitions from a pure titanium layer to a titanium-aluminum-vanadium layer, forming a gradient-coupled titanium alloy structure coating that can better adhere to the substrate surface to form a dense titanium alloy coating. In addition, the titanium-aluminum-vanadium layer gradually changes from a crystalline phase to an amorphous phase, and the final surface is a Zr, Ti, Cu, Ni, Be amorphous layer. Due to the amorphous structure, the atomic short-range order and long-range disorder, and the unique atomic stacking structure, the amorphous layer has high strength, high hardness, excellent wear resistance, corrosion resistance, ductility, and impact resistance. Comparative Example 1 does not have a gradient transition, so the two-phase interface does not generate a metallurgical reaction to form an interface phase structure, and the layer interface has poor bonding performance.

[0057] Comparative Example 2 only clads a titanium alloy coating with a gradient structure on the substrate. Since the corrosion performance of titanium alloy in sulfuric acid is not good, the corrosion rate is much higher than that of Examples 1-3. The surface of the titanium alloy with a crystalline structure has a lower hardness than the zirconium-based amorphous alloy. During the wear process, the titanium alloy is more severely worn.

[0058] Comparative Example 3 only sprays a zirconium-based amorphous alloy coating with a gradient structure on the substrate. Since there is no titanium alloy as a transition layer, the bonding strength between the zirconium-based amorphous coating and the substrate 316L is low, and the coating is easily detached during the wear process, resulting in poor wear resistance.

[0059] Comparative Example 1 and Example 1 have significant differences in corrosion and wear performance, mainly due to the fundamental differences in coating structure design. In Comparative Example 1, the coating is simply combined by titanium alloy and zirconium-based amorphous alloy without constructing a gradient structure. This simple combination method results in uneven distribution of elements within the coating and weak interaction between alloy elements, which cannot form an effective protective barrier. In Example 1, a gradient structure coating design is adopted, which accurately controls the composition and distribution of different materials to achieve a smooth transition from titanium alloy to zirconium-based amorphous alloy. This gradient structure not only enhances the interaction between elements within the coating, but also improves the overall uniformity and stability of the coating. Therefore, the coating of Example 1 exhibits better performance in corrosion resistance and wear resistance. In addition, the design of the gradient structure coating allows the material to disperse stress and reduce stress concentration when subjected to external force, thereby improving the hardness and strength of the coating. In contrast, the coating in Comparative Example 1 lacks a gradient structure, resulting in lower hardness and strength than Example 1, and thus performs poorly in the face of environmental challenges such as corrosion and wear.

[0060] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and do not limit the scope of protection of the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present application.

Claims

1. A method for preparing a zirconium-based amorphous alloy-titanium alloy composite coating, characterized in that: The preparation method includes the following steps: (1) Pre-treatment of the substrate, including surface grinding or sandblasting of the substrate, followed by cleaning and drying of the substrate; (2) A layered cladding process is used to clad the substrate in layers to form a gradient coupled titanium alloy layer. Then the titanium alloy layer is processed, trimmed, cleaned and dried. (3) A zirconium-based amorphous alloy coating with a gradient structure is applied to the surface of the titanium alloy layer by supersonic flame spraying technology. After post-treatment of the surface, a composite material coating with a gradient structure is obtained.

2. The method for preparing a zirconium-based amorphous alloy-titanium alloy composite material coating according to claim 1, characterized in that: In step (1), the substrate surface is smoothed by mechanical grinding with a roughness Ra < 0.

5. Then, the substrate is ultrasonically cleaned with alcohol and dried.

3. The method for preparing a zirconium-based amorphous alloy-titanium alloy composite coating according to claim 1, characterized in that: In step (1), corundum sandblasting is used to remove surface contaminants, and the surface roughness after treatment is Ra=8.0~10.

0. Then, the substrate is ultrasonically cleaned with alcohol and dried.

4. The method for preparing a zirconium-based amorphous alloy-titanium alloy composite material coating according to claim 1, characterized in that: The layered cladding in step (2) specifically includes: firstly, using Ti powder as raw material, cladding is performed to form a Ti layer of 50~150μm; secondly, using Ti and Al powders in equal molar ratio as raw material, cladding is performed to form a Ti and Al layer of 50~150μm; finally, using Al, V and Ti powders in equal molar ratio as raw material, cladding is performed to form a Ti, Al and V layer of 50~150μm, resulting in a gradient coupled titanium alloy layer with a total thickness of 300~350μm.

5. The method for preparing a zirconium-based amorphous alloy-titanium alloy composite material coating according to claim 4, characterized in that: The powder particle size is 10~60μm; the laser cladding powder feeding speed is 20~40g / min; the laser beam scanning speed of laser cladding is 60~120m / min; the laser beam emission power of laser cladding is 1~2kW; and the laser beam spot diameter of laser cladding is 1~3mm.

6. The method for preparing a zirconium-based amorphous alloy-titanium alloy composite material coating according to claim 1, characterized in that: The specific steps of step (3) for layered spraying of zirconium-based amorphous alloy coating include: firstly, using Zr, Ti, and Cu powders in equal molar ratios as raw materials, spraying to form a 100-150 μm Zr, Ti, and Cu amorphous layer; secondly, using Zr, Ti, Cu, and Ni powders in equal molar ratios as raw materials, spraying to form a 100-150 μm Zr, Ti, Cu, and Ni amorphous layer; and finally, using Zr, Ti, Cu, Ni, and Be powders in equal molar ratios as raw materials, spraying to form a 100-150 μm Zr, Ti, Cu, Ni, and Be amorphous layer, resulting in a zirconium-based amorphous alloy coating with a total thickness of 300-350 μm.

7. The method for preparing a zirconium-based amorphous alloy-titanium alloy composite material coating according to claim 6, characterized in that: The powder particle size is 15~45μm; the spraying distance is 350~380mm, the spraying speed is 250~350mm / s, the powder feeding rate is 45~60g / min, and the spraying oxygen flow rate is 40~50m³ / min. 3 / h, the kerosene flow rate for spraying is 20~25L / h.

8. The method for preparing a zirconium-based amorphous alloy-titanium alloy composite material coating according to claim 1, characterized in that: In step (2), the titanium alloy layer is processed and repaired by corundum sandblasting. The surface roughness of the treated titanium alloy layer is Ra=6.0~12.

0. Then, it is ultrasonically cleaned and dried with alcohol.

9. The method for preparing a zirconium-based amorphous alloy-titanium alloy composite coating according to claim 1, characterized in that: In step (3), the post-treatment of the surface specifically includes: repairing the rough parts of the surface, removing excess spraying material, and the surface roughness of the zirconium-based amorphous alloy coating after treatment is Ra=0.2~0.

8.

10. The zirconium-based amorphous alloy-titanium alloy composite material coating prepared by the method for preparing a zirconium-based amorphous alloy-titanium alloy composite material coating according to any one of claims 1-9, characterized in that: The zirconium-based amorphous alloy-titanium alloy composite coating has a gradient structure with crystalline and amorphous coupling.

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