CN118326317A - A preparation method of dual-phase nanoparticle reinforced alloy wear-resistant coating - Google Patents

Abstract

The invention discloses a preparation method of a dual-phase nanoparticle reinforced alloy wear-resistant coating, comprising the following steps: preparing raw materials for the wear-resistant coating; pouring the required raw materials into a ball mill for grinding; pouring the ground materials into a mixer for stirring and mixing evenly, adding a binder during the stirring process for coating; spraying a stainless steel substrate with atmospheric plasma spraying; using the creative method of the invention to significantly improve the wear resistance of the coating, while reducing the friction coefficient, and realizing the controllable deposition of the high-performance alloy wear-resistant coating.

Description

A preparation method of dual-phase nanoparticle reinforced alloy wear-resistant coating

Technical Field

The invention belongs to the technical field of thermal spraying and surface engineering, and in particular relates to a method for preparing a dual-phase nano-particle reinforced alloy wear-resistant coating.

Background technique

Atmospheric plasma spraying technology is based on the generation and use of plasma. In this process, the gas is heated and ionized to form plasma. Then, powder is injected into the plasma and sprayed through the nozzle onto the surface of the workpiece to form a coating. Compared with other surface engineering technologies, atmospheric plasma spraying generally has a higher deposition efficiency and can quickly form a uniform and dense coating.

In the prior art, alloy wear-resistant coatings are often used in mechanical industrial equipment, and NiCr alloy is a representative metal material. Since the wear-resistant coating has good high-temperature stability, it can maintain relatively good performance in high-temperature environments, which can greatly improve the service life of the machinery, and is very important for applications in high-temperature industrial equipment. However, its performance still has many limitations. Its defects in thermal fatigue, deposition uniformity, hardness, adhesion, etc. in actual applications will cause its own performance to be greatly limited, which is not enough to meet the application in some extreme wear environments, and due to the influence of the preparation process, the NiCr coating may show a certain surface roughness. These limitations will affect its tribological properties and the effect in actual application.

Summary of the invention

The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

In view of the above-mentioned and/or existing problems in the preparation of alloy wear-resistant coatings in the prior art, the present invention is proposed. The use of the creative method in the present invention significantly improves the wear resistance of the coating, while reducing the friction coefficient, thereby achieving controllable deposition of high-performance alloy wear-resistant coatings.

Therefore, the purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for preparing a dual-phase nanoparticle reinforced alloy wear-resistant coating, comprising the following steps:

Prepare raw materials for wear-resistant coating;

Pour the required raw materials into the ball mill for grinding;

Pour the ground material into a mixer and mix it evenly. During the mixing process, add a binder for coating.

The stainless steel substrate is sprayed by atmospheric plasma spraying.

As a preferred solution of the preparation method of the dual-phase nanoparticle reinforced alloy wear-resistant coating in the present invention, the stainless steel substrate is treated before spraying, specifically, the surface of the stainless steel substrate is ultrasonically cleaned with ethanol to remove impurities such as oil stains, and after cleaning, it is placed in an oven for drying; then, the surface of the stainless steel to be sprayed is sandblasted and roughened with brown corundum sand with a particle size of 24 mesh, and the roughness of the roughened particles is controlled to be 2-8μm.

As a preferred solution of the method for preparing the dual-phase nanoparticle reinforced alloy wear-resistant coating in the present invention, the grinding time is 2 hours.

As a preferred solution of the method for preparing the dual-phase nano-particle reinforced alloy wear-resistant coating in the present invention, the raw materials are Mo powder, BN powder and Ni20Cr powder.

As a preferred solution of the method for preparing the dual-phase nanoparticle reinforced alloy wear-resistant coating in the present invention, wherein: the masses of the Mo powder and the BN powder are the same.

As a preferred solution of the preparation method of the dual-phase nanoparticle reinforced alloy wear-resistant coating in the present invention, the mass proportions of the Mo powder, BN powder and Ni20Cr powder are 1-15%, 1-15% and 70%-98% respectively.

As a preferred solution of the method for preparing the dual-phase nanoparticle reinforced alloy wear-resistant coating in the present invention, the mass proportions of the Mo powder, BN powder and Ni20Cr powder are 10%, 10% and 80% respectively.

As a preferred scheme of the preparation method of the dual-phase nanoparticle reinforced alloy wear-resistant coating in the present invention, the parameters during coating are: current 500 A, Ar gas flow rate 35 L/min, _H2 flow rate 6 L/min, powder feeding rate 28-36 g/min, spraying distance 90-120 mm, translation speed of the spray gun 200 mm/s, and coating thickness 300 μm.

As a preferred solution of the method for preparing the dual-phase nano-particle reinforced alloy wear-resistant coating in the present invention, wherein: in the Ni20Cr powder, the mass percentages of Ni and Cr are 80% and 20% respectively.

As a preferred solution of the method for preparing the dual-phase nanoparticle reinforced alloy wear-resistant coating in the present invention, wherein: the binder is acrylic polysiloxane, and the mass proportion of the binder during stirring is 40%.

Compared with the prior art, the present invention has the following beneficial effects: a solid lubricating film and a ceramic interface film are successfully formed on a stainless steel substrate by introducing doped lubricating phase molybdenum and reinforcing phase boron nitride, and the wear resistance of the coating is significantly improved by using the creative method of the present invention, while the friction coefficient is reduced, thereby achieving controllable deposition of high-performance alloy wear-resistant coatings; the present invention can be applied to the preparation of alloy wear-resistant coatings.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

FIG. 1 is a schematic diagram of spraying in the present invention.

FIG. 2 is a microscopic morphology structure diagram of the raw material in Example 1.

FIG. 3 is a microscopic morphology of the coating prepared in Example 1.

FIG. 4 is a graph showing the friction coefficient of Mo/BN-Ni20Cr at different ratios of Examples 1 to 4.

FIG. 5 is a graph showing the friction coefficient of Mo/BN-Ni20Cr with different spraying parameters in Examples 5 to 9.

Detailed ways

In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the embodiments of the specification.

In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

The method for preparing the dual-phase nanoparticle reinforced alloy wear-resistant coating of the present invention comprises the following steps:

Prepare raw materials for wear-resistant coating, the raw materials are Mo powder, BN powder and Ni20Cr powder, the Mo powder and BN powder have the same mass, the mass proportions of the Mo powder, BN powder and Ni20Cr powder are 1-15%, 1-15% and 70%-98% respectively, and the mass percentages of Ni and Cr in the Ni20Cr powder are 80% and 20% respectively;

Pour the required raw materials into a ball mill and grind them for 2 hours;

Pour the ground material into a mixer and mix it evenly. During the mixing process, add a binder for coating. The binder is acrylic polysiloxane, and the weight of the binder accounts for 40% during mixing.

The stainless steel substrate is sprayed by atmospheric plasma spraying.

The stainless steel substrate was treated before spraying. Specifically, the surface of the stainless steel substrate was ultrasonically cleaned with ethanol to remove impurities such as oil and then placed in an oven for drying. Subsequently, the surface of the stainless steel substrate to be sprayed was roughened by sandblasting with brown corundum sand with a particle size of 24 mesh, and the roughness of the roughened particles was controlled at 2-8 μm.

During spraying, the spray gun was powered (existing technology, as shown in FIG1 ). The parameters during coating were: current 500 A, Ar gas flow rate 35 L/min, _H2 flow rate 6 L/min, powder feeding rate 28-36 g/min, spraying distance 90-120 mm, translation speed of the spray gun 200 mm/s, and coating thickness 300 μm.

Example 1

This embodiment provides a method for preparing a dual-phase nanoparticle reinforced alloy wear-resistant coating, comprising the following steps:

(1) preparing raw materials for wear-resistant coating, wherein the raw materials are Mo powder, BN powder and Ni20Cr powder, the Mo powder and BN powder have the same mass, the mass percentages of the Mo powder, BN powder and Ni20Cr powder are 10%, 10% and 80% respectively, and the mass percentages of Ni and Cr in the Ni20Cr powder are 80% and 20% respectively;

(2) Pour the required raw materials into a ball mill and grind them for 2 hours;

Pour the ground material into a mixer and mix it evenly. During the mixing process, add a binder for coating. The binder is acrylic polysiloxane, and the weight of the binder accounts for 40% during mixing.

(3) treating the stainless steel substrate, specifically, using ethanol to ultrasonically clean the surface of the stainless steel substrate to remove impurities such as oil stains, and then putting it into an oven for drying; then using brown corundum sand with a particle size of 24 mesh to roughen the surface of the stainless steel substrate, and the roughness of the roughened particles is controlled to be 2-8 μm;

(4) Atmospheric plasma spraying was used to generate plasma at normal pressure. The prepared metal powder was connected to the powder container through a conveying pipe. The current was 500 A, the Ar gas flow rate was 35 L/min, the _H2 flow rate was 6 L/min, the powder feeding rate was 32 g/min, the spraying distance was 100 mm, and the translation speed of the spray gun was 200 mm/s. The composite alloy wear-resistant coating was deposited on the surface of the stainless steel substrate. The coating thickness was 300 μm.

(5) After preparation, allow to cool naturally.

The prepared coating was subjected to ball-disc friction and wear experiments. The experiments were carried out simultaneously under the same conditions. The dual ball was a 5 mm Si ₃ N ₄ ball, the relative sliding speed was 0.1 m/s, the wear radius was 5 mm, and the sliding distance was 1000 m.

The results show that under non-lubricated conditions, the friction coefficient of the prepared coating is 0.39±0.05 and the wear rate is 4.2±0.08*10 ^-6 mm ³ /(N·m).

The microscopic morphology of the raw materials (three powders mixed together) (as shown in Figure 2) is that the main morphology is nanoparticles with a length of 50 nm to 150 nm, an average particle size of 110 nm, and a thickness of about 25 nm. Mo and BN are uniformly distributed on Ni20Cr as doping phases, with a high specific surface area and an average pore size of 180 nm.

As can be seen from Figure 3, the thickness of the prepared coating is uniform, with an average thickness of 300 μm, no obvious stratification phenomenon, and uniform distribution.

The present invention realizes the controllable deposition of high-performance alloy wear-resistant coating and the regulation of its organizational structure and interface mechanical properties by nano-scale lubricating phase Mo and reinforcing phase BN reinforced alloy coating, as well as specific setting of coating parameters, so as to improve the wear condition of the friction interface.

Example 2

This embodiment provides a method for preparing a dual-phase nanoparticle reinforced alloy wear-resistant coating, which is different from Example 1 in that the mass proportion of Mo powder in the raw material is 1%, and the mass proportion of BN powder is 1%.

The prepared coating was subjected to a ball-disc friction and wear test. The experiment was carried out simultaneously under the same conditions as Example 1, wherein the dual ball was a 5 mm Si ₃ N ₄ ball, the relative sliding speed was 0.1 m/s, the wear radius was 5 mm, and the sliding distance was 1000 m.

The results show that under non-lubricated conditions, the friction coefficient of the prepared coating is 0.57±0.05 and the wear rate is 1.6±0.09*10 ^-5 mm ³ /(N·m).

Example 3

This embodiment provides a method for preparing a dual-phase nanoparticle reinforced alloy wear-resistant coating, which is different from Example 1 in that the mass proportion of Mo powder in the raw material is 5%, and the mass proportion of BN powder is 5%.

The prepared coating was subjected to a ball-disc friction and wear test. The experiment was carried out simultaneously under the same conditions as Example 1, wherein the dual ball was a 5 mm Si ₃ N ₄ ball, the relative sliding speed was 0.1 m/s, the wear radius was 5 mm, and the sliding distance was 1000 m.

The results show that under non-lubricated conditions, the friction coefficient of the prepared coating is 0.49±0.03 and the wear rate is 1.3±0.15*10 ^-5 mm ³ /(N·m).

Example 4

This embodiment provides a method for preparing a dual-phase nanoparticle reinforced alloy wear-resistant coating, which is different from Example 1 in that the mass proportion of Mo powder in the raw material is 15%, and the mass proportion of BN powder is 15%.

The prepared coating was subjected to a ball-disc friction and wear test. The experiment was carried out simultaneously under the same conditions as Example 1, where a 5 mm Si3N4 ball was used as the dual ball, the relative sliding speed was 0.1 m/s, the wear radius was 5 mm, and the sliding distance was 1000 m.

The results show that under non-lubricated conditions, the friction coefficient of the prepared coating is 0.42±0.05 and the wear rate is 8.4±0.12*10 ^-6 mm ³ /(N·m).

Example 5

This embodiment provides a method for preparing a dual-phase nanoparticle reinforced alloy wear-resistant coating, which is different from Embodiment 1 in that in step (4), the spraying distance is 90 mm.

The prepared coating was subjected to a ball-disc friction and wear test. The experiment was carried out simultaneously under the same conditions as Example 1, wherein the dual ball was a 5 mm Si ₃ N ₄ ball, the relative sliding speed was 0.1 m/s, the wear radius was 5 mm, and the sliding distance was 1000 m.

The results show that under non-lubricated conditions, the friction coefficient of the prepared coating is 0.54±0.06 and the wear rate is 6.4±0.09*10 ^-6 mm ³ /(N·m).

Example 6

This embodiment provides a method for preparing a dual-phase nanoparticle reinforced alloy wear-resistant coating, which is different from Embodiment 1 in that in step (4), the spraying distance is 110 mm.

The prepared coating was subjected to a ball-disc friction and wear test. The experiment was carried out simultaneously under the same conditions as Example 1, where a 5 mm Si3N4 ball was used as the dual ball, the relative sliding speed was 0.1 m/s, the wear radius was 5 mm, and the sliding distance was 1000 m.

The results show that under non-lubricated conditions, the friction coefficient of the prepared coating is 0.48±0.06 and the wear rate is 7.5±0.06*10 ^-6 mm ³ /(N·m).

Example 7

This embodiment provides a method for preparing a dual-phase nanoparticle reinforced alloy wear-resistant coating, which is different from Embodiment 1 in that in step (4), the spraying distance is 120 mm.

The prepared coating was subjected to a ball-disc friction and wear test. The experiment was carried out simultaneously under the same conditions as Example 1, wherein the dual ball was a 5 mm Si ₃ N ₄ ball, the relative sliding speed was 0.1 m/s, the wear radius was 5 mm, and the sliding distance was 1000 m.

The results show that under non-lubricated conditions, the friction coefficient of the prepared coating is 0.51±0.06 and the wear rate is 9.4±0.05*10 ^-6 mm ³ /(N·m).

Example 8

This embodiment provides a method for preparing a dual-phase nanoparticle reinforced alloy wear-resistant coating, which is different from Embodiment 1 in that in step (4), the powder feeding rate is 28 g/min.

The prepared coating was subjected to a ball-disc friction and wear test. The experiment was carried out simultaneously under the same conditions as Example 1, where a 5 mm Si3N4 ball was selected as the dual ball, the relative sliding speed was 0.1 m/s, the wear radius was 5 mm, and the sliding distance was 1000 m.

The results show that under non-lubricated conditions, the friction coefficient of the prepared coating is 0.49±0.08 and the wear rate is 6.6±0.04*10 ^-6 mm ³ /(N·m).

Example 9

This embodiment provides a method for preparing a dual-phase nanoparticle reinforced alloy wear-resistant coating, which is different from Embodiment 1 in that in step (4), the powder feeding rate is 36 g/min.

The prepared coating was subjected to a ball-disc friction and wear test. The experiment was carried out simultaneously under the same conditions as Example 1, wherein the dual ball was a 5 mm Si ₃ N ₄ ball, the relative sliding speed was 0.1 m/s, the wear radius was 5 mm, and the sliding distance was 1000 m.

The results show that under non-lubricated conditions, the friction coefficient of the prepared coating is 0.53±0.09 and the wear rate is 8.7±0.06*10 ^-6 mm ³ /(N·m).

It can be clearly seen from the above embodiments that Embodiment 1 is the best implementation mode. The use of the present invention significantly improves the wear resistance of the alloy wear-resistant coating, reduces the friction coefficient, and realizes the controllable deposition of the high-performance alloy wear-resistant coating.

It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention 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 invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims (10)

1. A preparation method of a biphase nanoparticle reinforced alloy wear-resistant coating is characterized by comprising the following steps of: comprises the steps of,

Preparing raw materials for the wear-resistant coating;

Pouring the required raw materials into a ball mill tank for grinding;

Pouring the ground materials into a stirrer for stirring, uniformly mixing, and adding a binder in the stirring process for coating operation;

and adopting atmospheric plasma spraying to spray the stainless steel matrix.

2. The method for preparing the dual-phase nanoparticle reinforced alloy wear-resistant coating according to claim 1, wherein the method comprises the following steps: treating the stainless steel substrate before spraying, specifically, ultrasonically cleaning the surface of the stainless steel substrate by ethanol to remove impurities such as greasy dirt and the like, and putting the stainless steel substrate into an oven for drying after cleaning; then carrying out sand blasting coarsening treatment on the surface of the stainless steel to be sprayed by brown corundum sand with the granularity of 24 meshes, and controlling the coarsened particle roughness to be 2-8 mu m.

3. A method for preparing the dual-phase nanoparticle reinforced alloy wear-resistant coating as claimed in claim 2, wherein: the milling time was 2 hours.

4. A method for preparing a dual phase nanoparticle reinforced alloy wear resistant coating as claimed in any one of claims 1 to 3, wherein: the raw materials are Mo powder, BN powder and Ni20Cr powder.

5. The method for preparing the dual-phase nanoparticle reinforced alloy wear-resistant coating according to claim 4, wherein the method comprises the following steps: the mass of the Mo powder and the BN powder is the same.

6. The method for preparing the dual-phase nanoparticle reinforced alloy wear-resistant coating according to claim 5, wherein the method comprises the following steps: the mass ratio of the Mo powder, the BN powder and the Ni20Cr powder is 1-15%, 1-15% and 70-98% respectively.

7. The method for preparing the dual-phase nanoparticle reinforced alloy wear-resistant coating according to claim 6, wherein the method comprises the following steps: the mass ratio of the Mo powder, the BN powder and the Ni20Cr powder is 10%, 10% and 80%, respectively, the average grain size of the BN powder is 200 nm, and the grain size of the Ni20Cr powder is 45-85 mu m.

8. A method for preparing a dual phase nanoparticle reinforced alloy wear resistant coating as claimed in any one of claims 1 to 3, wherein: the parameters of the coating are that the current is 500A, the Ar gas flow is 35L/min, the H ₂ flow is 6L/min, the powder feeding speed is 28-36 g/min, the spraying distance is 90-120 mm, the translation speed of the spraying gun is 200 mm/s, and the thickness of the coating is 300 mu m.

9. A method for preparing a dual phase nanoparticle reinforced alloy wear resistant coating as claimed in any one of claims 1 to 3, wherein: in the Ni20Cr powder, the mass percentages of Ni and Cr are 80% and 20%, respectively.

10. The method for preparing the dual-phase nanoparticle reinforced alloy wear-resistant coating according to claim 8, wherein the method comprises the following steps: the adhesive is acrylic polysiloxane, and the mass ratio of the adhesive is 40% when stirring.