NICKEL-BASED WEAR-RESISTANT COATING BASED ON PLASMA CLADDING AND PREPARATION METHOD THEREOF

Description

CROSS REFERENCE TO RELATED APPLICATION

This patent application claims the benefit and priority of Chinese Patent Application No. 202410612158.8, filed with the China National Intellectual Property Administration on May 17, 2024, the disclosure of which is incorporated by reference herein in its entirety as part of the present application.

TECHNICAL FIELD

The present disclosure relates to the technical field of metal plating and cladding, and in particular to a nickel-based wear-resistant coating based on plasma cladding and a preparation method thereof.

BACKGROUND

Compared with laser cladding, plasma cladding is suitable for large-scale production due to its high plasma arc heat, rapid heating, high energy utilization (no light reflection), controllable cladding layer quality, wide range of material selection, easy operation, and low equipment cost. Many studies have been conducted on plasma cladding, plasma spraying, and laser cladding in the prior art, indicating that the existing nickel-based, cobalt-based, iron-based and other alloy coatings have poor wear resistance under severe abrasive wear, sliding wear, or impact wear. Existing research also shows that a metal-ceramic composite coating prepared by adding high-hardness and wear-resistant ceramic particles into a self-dissolving alloy powder can take into account the toughness of metal while maintaining the wear resistance of ceramic. However, the metal-ceramic composite coating still has defects such as poor interface connection, poor wettability, large internal stress, or large crack sensitivity, such that cracks and air pores may appear in actual work, thus causing coating failure.

WC, a compound composed of tungsten and carbon, is a black hexagonal crystal with a metallic luster. The WC exhibits an extremely high hardness second only to that of diamond, and is an excellent wear-resistant material. Due to high hardness and desirable wear resistance, WC is widely used in cutting tools, abrasive tools, or mining equipment. When a single WC coating is prepared by plasma cladding, the WC is easy to settle, and WC particles are deposited at the bottom of a cladding layer during the cladding, resulting in a large number of defects such as air pores and cracks in the cladding layer. As a result, the cladding layer has low hardness and poor wear resistance.

SUMMARY

The present disclosure aims to overcome the technical defect that WC particles are easily deposited at the bottom of a cladding layer during the preparation of a single WC coating, resulting in a large number of air pores and cracks in the cladding layer. The present disclosure provides a nickel-based wear-resistant coating based on plasma cladding and a preparation method thereof.

The present disclosure provides a nickel-based wear-resistant coating based on plasma cladding, where a cladding powder of the nickel-based wear-resistant coating includes a WC powder with a mass percentage of 45% to 65%, a TiC powder with a mass percentage of 1% to 3%, an Yb₂O₃ powder with a mass percentage of 1% to 3%, and a Ni60 powder as a balance.

WC powder: WC particles have the advantages of high melting point, high hardness, and desirable stability, and the WC particles show desirable wettability with Ni-based metals. An increase in the WC particle content helps to enhance a hardness of the cladding layer and improve the wear resistance. During the plasma cladding, the WC particles form a chemical metallurgical bond with the bonding phase under the action of a high-energy field, thereby increasing a density of the microstructure in the cladding layer, reducing the formation of defects, and improving the wear resistance of the cladding layer.

TiC powder: TiC particles can improve a strength of the wear-resistant coating microstructure. The TiC particles have a relatively low thermal expansion coefficient, such that the cladding layer shows desirable thermal stability when experiencing temperature changes. TiC particles are a ceramic material with high melting point, high hardness, low density, and stable chemical properties. TiC particles can form a ceramic phase with high hardness and high melting point, which can significantly improve the hardness and wear resistance of the cladding layer. When the TiC is dispersed in the metal sheet substrate in the form of particles, it acts as a hard point support during the wear process to improve the wear resistance of the cladding layer, thus reducing the friction coefficient, and playing a desirable role in surface strengthening.

Yb₂O₃ powder: Yb₂O₃ particles can improve the fluidity of the powder and increase the density of the nickel-based wear-resistant coating. Since the high-melting Yb₂O₃ particles have desirable wettability, they can accelerate the internal convection of the cladding layer, increase the density of the cladding layer, and improve a bonding force between the cladding layer and the metal sheet substrate. Yb₂O₃ particles play the role of a strengthening phase in the cladding layer. The addition of Yb₂O₃ particles can promote the decomposition of WC, increase the precipitation of carbide hard phase, and effectively improve the abrasive wear resistance of the cladding layer. The Yb₂O₃ particles have high oxidation resistance at high temperatures and can effectively resist the influence of high-temperature oxidation on the performance of cladding layer. Therefore, the performance of the cladding layer with Yb₂O₃ is better than that of the cladding layer without Yb₂O₃.

Ni60 powder: Ni60 is an alloy powder with excellent self-fluxing property, high toughness, and desirable electrical resistance. Ni60 particles in plasma cladding can mainly enhance the wear resistance of the cladding layer, optimize the microstructure of the cladding layer, and improve the hardness.

Preferably, the WC powder has a particle size of 74 μm to 124 μm, the TiC powder has a particle size of 48 μm to 74 μm, the Yb₂O₃ powder has a particle size of 38 μm to 75 μm, and the Ni60 powder has a particle size of 48 μm to 104 μm. Powders with similar particle sizes are easy to mix evenly. This is because under the same other conditions, the powders with a same particle size are not easy to separate and segregate during the movement, such that the powders can be mixed smoothly and evenly. In the plasma cladding, a plasma cladding powder with similar particle size and uniform mixing can avoid the phenomenon of large particles settling first, and can make the cladding layer structure more uniform and dense.

The present disclosure further provides a preparation method of a nickel-based wear-resistant coating based on plasma cladding, including the following steps:

• • step 1, subjecting a surface of a metal sheet substrate to cleaning and pretreatment;
  • step 2, preparing a cladding powder of the nickel-based wear-resistant coating, where the cladding powder includes a WC powder with a mass percentage of 45% to 65%, a TiC powder with a mass percentage of 1% to 3%, an Yb₂O₃ powder with a mass percentage of 1% to 3%, and a Ni60 powder as a balance; and mixing the cladding powder evenly in a planetary ball mill and storing under vacuum to obtain a plasma cladding powder;
  • step 3, cladding the plasma cladding powder prepared in step 2 on the surface of the metal sheet substrate treated in step 1 by plasma cladding such that the plasma cladding powder forms the nickel-based wear-resistant coating on the surface of the metal sheet substrate; and
  • step 4, conducting a post-treatment.

Preferably, the cleaning and pretreatment in step 1 includes: polishing the metal sheet substrate with sandpaper, subjecting a resulting polished metal sheet substrate to ultrasonic cleaning in anhydrous ethanol, and then drying a resulting cleaned metal sheet substrate for later use. Cleaning is a necessary treatment before plasma cladding. The polishing with an automatic polishing machine is to effectively remove the oil stains carried by the metal sheet substrate during transportation or placement, as well as the oxide layer that appears when in contact with the air. Pretreatment of the metal sheet substrate can ensure a high bonding strength between the cladding layer and the substrate. The polishing can be conducted with sandpapers of 240 mesh and 400 mesh. The anhydrous ethanol can achieve a desirable cleaning effect, while the ultrasonic cleaning has the advantages of high efficiency and environmental protection.

Preferably, the planetary ball mill in step 2 works at 220 r/min to 260 r/min for 8 h to 12 h, and a ball mill tank of the planetary ball mill is a vacuum stainless steel tank. The planetary ball mill has a high sealing characteristic, which can prevent other unnecessary gases from entering during ball milling and mixing, thereby preventing oxidation of the powder. The vacuum stainless steel tank can also effectively prevent the powder from being oxidized during ball milling.

Preferably, the plasma cladding in step 3 includes the following parameters: a main arc current of 80 A to 120 A, a pilot arc current of 23 A to 27 A, a scanning speed of 180 mm/min to 250 mm/min, a powder feeding rate of 15 g/min to 20 g/min, an ion gas flow rate of 1.5 L/min to 3 L/min, a powder feeding gas flow rate of 1.5 L/min to 3 L/min, and a shielding gas flow rate of 10 L/min to 15 L/min. The various parameters in the plasma cladding can be adjusted according to performance requirements of the prepared cladding layer to obtain optimal cladding effect and coating quality.

Preferably, the plasma cladding powder in the plasma cladding in step 3 is delivered to the surface of the metal sheet substrate by coaxial powder feeding.

Preferably, the post-treatment in step 4 is one selected from the group consisting of room-temperature natural cooling, sand cooling, oil cooling, and annealing. Different post-treatment methods can produce different organizational structures. Therefore, a specific post-treatment method can be selected according to actual demands.

Compared with the prior art, the technical solutions provided by the present disclosure have the following remarkable effects:

• • I. In the present disclosure, the nickel-based wear-resistant coating prepared by plasma cladding has a dense structure and high bonding strength with the metal sheet substrate. The alloy carbides dispersed in the cladding layer can effectively improve the abrasive wear resistance of the cladding layer. In addition, the preparation method can prepare a nickel-based wear-resistant coating with a thickness of 1 mm to 2.5 mm on the surface of the metal sheet substrate. The nickel-based wear-resistant coating has an average hardness of not less than 550 HV, and the nickel-based wear-resistant coating shows high grain boundary strength, density, and overall strength.
  • II. In the present disclosure, the preparation method improves the fluidity of plasma cladding powder, increases the solubility of WC powder, promotes the decomposition of WC particles, and can precipitate alloy hard phase by adding an Yb₂O₃ powder. The prepared nickel-based wear-resistant coating has high hardness and desirable wear resistance. In the process of friction and wear, the alloy hard phase particles can effectively reduce a wear loss of the cladding layer during abrasive wear, sliding wear, or impact wear, thereby protecting the bonding phase and reducing the friction factor during the friction. Under the action of plasma cladding, the hard phase generated in the nickel-based wear-resistant coating has a compact structure and small grain boundaries. The tightly-arranged hard phase structure can improve the mechanical properties of the metal, reduce the generation of cracks and air pores, and enable the metal sheet substrate to better disperse and transfer loads when subjected to external stress, thereby improving the overall mechanical properties of the metal sheet substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings incorporated into this specification and constituting a part of this specification illustrate the embodiments of the present disclosure, and are used together with this specification to explain the principles of the present disclosure.

To describe the technical solutions in the examples of the present disclosure or in the prior art more clearly, the drawings that need to be used in the description of the examples or the prior art will be briefly introduced below. Obviously, other drawings can be obtained by those of ordinary skill in the art based on these drawings without creative work.

FIG. 1 shows a schematic diagram of a microstructure of the plasma cladding layer on a sample I in Example 1 of the present disclosure;

FIG. 2 shows a schematic diagram of a microstructure of the plasma cladding layer on a sample II in Example 2 of the present disclosure;

FIG. 3 shows a schematic diagram of a microstructure of the plasma cladding layer on a sample III in Comparative Example 1 of the present disclosure;

FIG. 4 shows a schematic diagram of a microstructure of the plasma cladding layer on a sample IV in Comparative Example 2 of the present disclosure;

FIG. 5 shows a comparison of the wear losses of sample I in Example 1, sample II in Example 2, sample III in Comparative Example 1, and sample IV in Comparative Example 2 of the present disclosure under the same friction test conditions;

FIG. 6 shows a schematic diagram of a wear scar profile of the sample I in Example 1 of the present disclosure;

FIG. 7 shows a schematic diagram of a wear scar profile of the sample II in Example 2 of the present disclosure;

FIG. 8 shows a schematic diagram of a wear scar profile of the sample III in Comparative Example 1 of the present disclosure;

FIG. 9 shows a schematic diagram of a wear scar profile of the sample IV in Comparative Example 2 of the present disclosure; and

FIG. 10 shows hardness curves of sample I in Example 1, sample II in Example 2, sample III in Comparative Example 1, and sample IV in Comparative Example 2 of the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

To make the objectives, features and advantages of the present disclosure more comprehensible, the present disclosure is described in detail below with reference to the drawings and specific examples. It should be noted that examples in the present disclosure or features in the examples may be combined with one another without conflict.

Many specific details are set forth in the following description to facilitate a full understanding of the present disclosure. The described examples are merely some rather than all of the embodiments of the present disclosure.

The specific examples of the present disclosure are described in detail below with reference to the accompanying drawings.

In an example, as shown in FIG. 1 to FIG. 10, the present disclosure provides a preparation method of a nickel-based wear-resistant coating based on plasma cladding, including the following steps:

• • step 1, subjecting a surface of a metal sheet substrate to cleaning and pretreatment; where the cleaning and pretreatment specifically includes polishing the metal sheet substrate with 200 mesh, 400 mesh, and 600 mesh sandpapers in sequence, such that surface oxides, rust, and rough burrs of the metal are polished; subjecting a resulting polished metal sheet substrate to ultrasonic cleaning in anhydrous ethanol, and then drying a resulting cleaned metal sheet substrate for later use;
  • step 2, preparing a cladding powder of the nickel-based wear-resistant coating, where the cladding powder includes a WC powder with a mass percentage of 45% to 65%, a TiC powder with a mass percentage of 1% to 3%, an Yb₂O₃ powder with a mass percentage of 1% to 3%, and a Ni60 powder as a balance; the WC powder has a particle size of 74 μm to 124 μm, the TiC powder has a particle size of 48 μm to 74 μm, the Yb₂O₃ powder has a particle size of 38 μm to 75 μm, and the Ni60 powder has a particle size of 48 μm to 104 μm; and mixing the cladding powder evenly in a planetary ball mill and storing under vacuum to obtain a plasma cladding powder; where the planetary ball mill works at 220 r/min to 260 r/min for 10 h to 12 h, and a ball mill tank of the planetary ball mill is a vacuum stainless steel tank;
  • step 3, cladding the plasma cladding powder prepared in step 2 on the surface of the metal sheet substrate treated in step 1 by plasma cladding such that the plasma cladding powder forms the nickel-based wear-resistant coating on the surface of the metal sheet substrate; the plasma cladding powder in the plasma cladding is delivered to the surface of the metal sheet substrate by coaxial powder feeding, and the plasma cladding includes the following parameters: a main arc current of 80 A to 120 A, a pilot arc current of 23 A to 27 A, a scanning speed of 180 mm/min to 250 mm/min, a powder feeding rate of 15 g/min to 20 g/min, an ion gas flow rate of 1.5 L/min to 3 L/min, a powder feeding gas flow rate of 1.5 L/min to 3 L/min, and a shielding gas flow rate of 10 L/min to 15 L/min; and
  • step 4, conducting a post-treatment; where the post-treatment is one selected from the group consisting of room-temperature natural cooling, sand cooling, oil cooling, and annealing, and lasts for 20 min to 30 min.

In the present disclosure, the surface treatment of the metal sheet substrate, the selection of the powder composition and the ratio, and the selection of the plasma cladding parameters are described, such that the technical personnel in the field can obtain a detailed preparation method. The preparation method can obtain a nickel-based wear-resistant coating with a dense structure; and combined with the following specific examples and comparative examples for comparison, the beneficial effects are more obvious through result analysis.

EXAMPLE 1

• • Step 1, a surface of a 42CrMo steel sheet substrate was subjected to cleaning and pretreatment; where the cleaning and pretreatment specifically included: the 42CrMo steel sheet substrate was polished with 200 mesh, 400 mesh, and 600 mesh sandpapers in sequence, such that surface oxides, rust, and rough burrs of the metal were polished; a resulting polished metal sheet substrate was subjected to ultrasonic cleaning in anhydrous ethanol, and then a resulting steel sheet substrate was dried for later use.
  • Step 2, a cladding powder of the nickel-based wear-resistant coating was prepared, where the cladding powder included a WC powder with a mass percentage of 50%, a TiC powder with a mass percentage of 1%, an Yb₂O₃ powder with a mass percentage of 1%, and a Ni60 powder as a balance; the WC powder had a particle size of 74 μm to 124 μm, the TiC powder had a particle size of 48 μm to 74 μm, the Yb₂O₃ powder had a particle size of 38 μm to 75 μm, and the Ni60 powder had a particle size of 48 μm to 104 μm; and the cladding powder was mixed evenly in a planetary ball mill and stored under vacuum to obtain a plasma cladding powder; where the planetary ball mill worked at 240 r/min for 10 h, and a ball mill tank of the planetary ball mill was a vacuum stainless steel tank.
  • Step 3, the plasma cladding powder prepared in step 2 on the surface of the 42CrMo steel sheet substrate treated in step 1 was clad by plasma cladding such that the plasma cladding powder formed the nickel-based wear-resistant coating on the surface of the metal sheet substrate; the plasma cladding powder in the plasma cladding was delivered to the surface of the metal sheet substrate by coaxial powder feeding, and the plasma cladding included the following parameters: a main arc current of 100 A, a pilot arc current of 25 A, a scanning speed of 210 mm/min, a powder feeding rate of 18 g/min, an ion gas flow rate of 2 L/min, a powder feeding gas flow rate of 2 L/min, and a shielding gas flow rate of 12 L/min.
  • Step 4, a post-treatment was conducted; where the sample was subjected to sand cooling for 25 min to obtain a sample I.

The preparation method of a nickel-based wear-resistant coating based on plasma cladding could prepare the sample I. The nickel-based wear-resistant coating of the sample I, namely a cladding layer, had an average hardness of 675 HV, and a microstructure of the cladding layer of sample I was shown in FIG. 1. In the friction and wear experiment, the sample I had a wear loss of 7.97 mg, where the conditions of the friction and wear experiment included: a grinding ball material was Si₃N₄, a load was 80 N, a reciprocating frequency was 1,000 times/min, a test time was 30 min, and dry friction was adopted. The friction and wear experiment indicated that the sample I had desirable wear resistance.

EXAMPLE 2

• • Step 1, a surface of a 42CrMo steel sheet substrate was subjected to cleaning and pretreatment; where the cleaning and pretreatment specifically included: the 42CrMo steel sheet substrate was polished with 200 mesh, 400 mesh, and 600 mesh sandpapers in sequence, such that surface oxides, rust, and rough burrs of the metal surface were polished; a resulting polished metal sheet substrate was subjected to ultrasonic cleaning in anhydrous ethanol, and then a resulting steel sheet substrate was dried for later use.

Step 2, a cladding powder of the nickel-based wear-resistant coating was prepared, where the cladding powder included a WC powder with a mass percentage of 65%, a TiC powder with a mass percentage of 1%, an Yb₂O₃ powder with a mass percentage of 3%, and a Ni60 powder as a balance; the WC powder had a particle size of 74 μm to 124 μm, the TiC powder had a particle size of 48 μm to 74 μm, the Yb₂O₃ powder had a particle size of 38 μm to 75 μm, and the Ni60 powder had a particle size of 48 μm to 104 μm; and the cladding powder was mixed evenly in a planetary ball mill and stored under vacuum to obtain a plasma cladding powder; where the planetary ball mill worked at 240 r/min for 10 h, and a ball mill tank of the planetary ball mill was a vacuum stainless steel tank.

• • Step 3, the plasma cladding powder prepared in step 2 on the surface of the 42CrMo steel sheet substrate treated in step 1 was clad by plasma cladding such that the plasma cladding powder formed the nickel-based wear-resistant coating on the surface of the metal sheet substrate; the plasma cladding powder in the plasma cladding was delivered to the surface of the metal sheet substrate by coaxial powder feeding, and the plasma cladding included the following parameters: a main arc current of 105 A, a pilot arc current of 25 A, a scanning speed of 240 mm/min, a powder feeding rate of 17 g/min, an ion gas flow rate of 2 L/min, a powder feeding gas flow rate of 2 L/min, and a shielding gas flow rate of 12 L/min.
  • Step 4, a post-treatment was conducted; where the sample was subjected to sand cooling for 25 min to obtain a sample II.

The preparation method of a nickel-based wear-resistant coating based on plasma cladding could prepare the sample II. The nickel-based wear-resistant coating of the sample II, namely a cladding layer, had an average hardness of 814 HV, and a microstructure of the cladding layer of sample II was shown in FIG. 2. In the friction and wear experiment, the sample II had a wear loss of 6.19 mg, where the conditions of the friction and wear experiment included: a grinding ball material was Si₃N₄, a load was 80 N, a reciprocating frequency was 1,000 times/min, a test time was 30 min, and dry friction was adopted. The friction and wear experiment indicated that the sample II had desirable wear resistance.

COMPARATIVE EXAMPLE 1

• • Step 1, a surface of a 42CrMo steel sheet substrate was subjected to cleaning and pretreatment; where the cleaning and pretreatment specifically included: the 42CrMo steel sheet substrate was polished with 200 mesh, 400 mesh, and 600 mesh sandpapers in sequence, such that surface oxides, rust, and rough burrs of the metal surface were polished; a resulting polished metal sheet substrate was subjected to ultrasonic cleaning in anhydrous ethanol, and then a resulting steel sheet substrate was dried for later use.
  • Step 2, a cladding powder of the nickel-based wear-resistant coating was prepared, where the cladding powder included a WC powder with a mass percentage of 50%, a TiC powder with a mass percentage of 1%, and a Ni60 powder as a balance; the WC powder had a particle size of 74 μm to 124 μm, the TiC powder had a particle size of 48 μm to 74 μm, and the Ni60 powder had a particle size of 48 μm to 104 μm; and the cladding powder was mixed evenly in a planetary ball mill and stored under vacuum to obtain a plasma cladding powder; where the planetary ball mill worked at 240 r/min for 10 h, and a ball mill tank of the planetary ball mill was a vacuum stainless steel tank.
  • Step 3, the plasma cladding powder prepared in step 2 on the surface of the 42CrMo steel sheet substrate treated in step 1 was clad by plasma cladding such that the plasma cladding powder formed the nickel-based wear-resistant coating on the surface of the metal sheet substrate; the plasma cladding powder in the plasma cladding was delivered to the surface of the metal sheet substrate by coaxial powder feeding, and the plasma cladding included the following parameters: a main arc current of 102 A, a pilot arc current of 25 A, a scanning speed of 220 mm/min, a powder feeding rate of 16 g/min, an ion gas flow rate of 2 L/min, a powder feeding gas flow rate of 2 L/min, and a shielding gas flow rate of 12 L/min.
  • Step 4, a post-treatment was conducted; where the sample was subjected to sand cooling for 25 min to obtain a sample III.

The preparation method in Comparative Example 1 could prepare the sample III. The nickel-based wear-resistant coating of the sample III, namely a cladding layer, had an average hardness of 583 HV, and a microstructure of the cladding layer of sample III was shown in FIG. 3. In the friction and wear experiment, the sample III had a wear loss of 8.94 mg, where the conditions of the friction and wear experiment included: a grinding ball material was Si₃N₄, a load was 80 N, a reciprocating frequency was 1,000 times/min, a test time was 30 min, and dry friction was adopted.

COMPARATIVE EXAMPLE 2

• • Step 1, a surface of a 42CrMo steel sheet substrate was subjected to cleaning and pretreatment; where the cleaning and pretreatment specifically included: the 42CrMo steel sheet substrate was polished with 200 mesh, 400 mesh, and 600 mesh sandpapers in sequence, such that surface oxides, rust, and rough burrs of the metal surface were polished; a resulting polished metal sheet substrate was subjected to ultrasonic cleaning in anhydrous ethanol, and then a resulting steel sheet substrate was dried for later use.
  • Step 2, a cladding powder of the nickel-based wear-resistant coating was prepared, where the cladding powder included a WC powder with a mass percentage of 65%, a TiC powder with a mass percentage of 1%, and a Ni60 powder as a balance; the WC powder had a particle size of 74 μm to 124 μm, the TiC powder had a particle size of 48 μm to 74 μm, and the Ni60 powder had a particle size of 48 μm to 104 μm; and the cladding powder was mixed evenly in a planetary ball mill and stored under vacuum to obtain a plasma cladding powder; where the planetary ball mill worked at 240 r/min for 10 h, and a ball mill tank of the planetary ball mill was a vacuum stainless steel tank.
  • Step 3, the plasma cladding powder prepared in step 2 on the surface of the 42CrMo steel sheet substrate treated in step 1 was clad by plasma cladding such that the plasma cladding powder formed the nickel-based wear-resistant coating on the surface of the metal sheet substrate; the plasma cladding powder in the plasma cladding was delivered to the surface of the metal sheet substrate by coaxial powder feeding, and the plasma cladding included the following parameters: a main arc current of 100 A, a pilot arc current of 25 A, a scanning speed of 230 mm/min, a powder feeding rate of 16 g/min, an ion gas flow rate of 2 L/min, a powder feeding gas flow rate of 2 L/min, and a shielding gas flow rate of 12 L/min.
  • Step 4, a post-treatment was conducted; where the sample was subjected to sand cooling for 25 min to obtain a sample IV.

The preparation method in Comparative Example 2 could prepare the sample IV. The nickel-based wear-resistant coating of the sample IV, namely a cladding layer, had an average hardness of 668 HV, and a microstructure of the cladding layer of sample IV was shown in FIG. 4. In the friction and wear experiment, the sample III had a wear loss of 9.25 mg, where the conditions of the friction and wear experiment included: a grinding ball material was Si₃N₄, a load was 80 N, a reciprocating frequency was 1,000 times/min, a test time was 30 min, and dry friction was adopted.

By comparing Example 1 and Example 2, Example 1 and Comparative Example 1, as well as Example 2 and Comparative Example, it was seen that an increase in the Yb₂O₃ powder content directly showed that the hardness of the cladding layer increased, and the wear loss of the cladding layer decreased. Yb₂O₃ particles played the role of a strengthening phase in the cladding layer. The addition of Yb₂O₃ particles increased the solubility of WC powder, promoted the decomposition of WC, and increased the precipitation of carbide hard phase. With the convection inside the molten pool, the alloy hard phase was evenly distributed inside the cladding layer, avoiding internal stress concentration, thus increasing the density of the cladding layer, forming dispersion strengthening, effectively improving the abrasive wear resistance of the cladding layer, and increasing the hardness and wear resistance of the cladding layer. It was observed from the microscopic interface that Yb₂O₃ particles could reduce the generation of cracks and air pores in the cladding layer.

TiC particles played an important role in the cladding layer. During the cladding, TiC could react with the metal sheet substrate to form carbide particles with strengthening effects, which could effectively improve the hardness, wear resistance, and corrosion resistance of the cladding layer. In addition, TiC particles could refine grains and improve the toughness of the cladding layer. Therefore, TiC particles in the cladding layer could improve the comprehensive performance of the material, making it have better wear resistance, corrosion resistance, and fatigue resistance.

In the present disclosure, the cladding layer was compared under the condition of fine-tuning the plasma parameters. By comparing Example 1, Example 2, Comparative Example 1, and Comparative Example 2, it was seen that the increase in WC content could significantly increase the hardness and wear resistance of the cladding layer. However, as shown in Comparative Examples 1 and 2, simply increasing the WC content might increase the air pores and internal cracks in the cladding layer. Therefore, in Example 1 and Example 2, the Yb₂O₃ content was increased to further improve a mass of the cladding layer, thus achieving a cladding structure with stronger comprehensive performance.

Example 1 and Comparative Example 1 were preparations of nickel-based wear-resistant coatings with different Yb₂O₃ contents at a same WC powder content. By analyzing the hardness and wear resistance of the cladding layer in Sample I of Example 1 and Sample III of Comparative Example 1 in combination with FIG. 5 and FIG. 10, it was found that the addition of Yb₂O₃ increased the wear resistance and overall hardness of the cladding layer. Comparing Example 2 with Example 1, the Yb₂O₃ content and WC content in Example 2 were increased compared with those in Example 1, and correspondingly, the strength and wear resistance of Sample II in Example 2 were better than those of Sample I in Example 1. Comparing Example 2 with Comparative Example 2: in Comparative Example 2, no Yb₂O₃ powder was added, and the wear resistance and overall hardness of sample II in Example 2 were significantly improved compared with those of sample IV in Comparative Example 2.

By comparing the microstructures of FIG. 1 and FIG. 3, it was seen that the adverse factors such as air pores and micro cracks of sample III in Comparative Example 1 were significantly increased, and the metal bonding density of the microstructure was worse. In the hardness test and wear resistance analysis, the wear resistance and hardness of Comparative Example 1 were also the worst. Relatively speaking, the metal bonding phase of sample I in Example 1 was tighter, such that a better cladding layer performance was achieved.

As shown in FIG. 2 and FIG. 4, the hard phase of sample II in Example 2 was closely arranged, and the carbide phase in the microstructure was evenly distributed. The cladding layer of sample II in Example 2 had better mechanical properties, and the strength and toughness of the cladding layer were better. Since the boundaries between grains were reduced, the material was less prone to cracking, deformation, and splitting during the processing. The tightly-arranged microstructure could improve the mechanical properties of the metal, such as strength, plasticity, and toughness. In addition, the reduction in the boundaries between grains enabled the metal sheet substrate to better disperse and transfer loads when being subjected to external stress, thereby improving the overall mechanical properties of the metal sheet substrate.

Comparison between FIG. 1 and FIG. 3 showed that the Yb₂O₃ powder increased the internal fluidity of the cladding powder, reduced the internal temperature gradient of the cladding layer, and inhibited the growth of coarse columnar crystals in the cladding layer. Comparing FIG. 2 and FIG. 1, Yb₂O₃ powder could promote the decomposition of WC and increase the precipitation of carbide hard phase, and the carbide hard phase was transformed from blocky carbide phase into petal-shaped and needle-shaped carbide phase. With the internal convection flow, the carbide hard phase was dispersed inside the cladding layer, thus avoiding internal stress concentration, reducing crack sensitivity, and increasing mechanical properties. With the increase of Yb₂O₃ powder content, the oxidation area inside the cladding layer decreased, thus reducing the internal oxidation of the cladding layer.

As shown in FIG. 6 and FIG. 7, a small amount of material accumulation occurred in the wear scars of sample I of Example 1 and sample II of Example 2, and the wear scar depths were 71.5 μm and 69.1 μm, respectively. Comparing FIG. 8 and FIG. 9, the wear scar depths of sample III of Comparative Example 1 and sample IV of Comparative Example 2 were significantly reduced, especially the wear scar surface of sample III in Comparative Example 1 not only had plastic deformation, but also showed obvious adhesive wear marks. FIG. 6, FIG. 7, FIG. 8, and FIG. 9 indicated that the increase in the content of the Yb₂O₃ powder could increase the fluidity of the molten pool, enhance the toughness of the cladding layer structure, adjust the friction performance, and improve the wear resistance and hardness of the cladding layer, such that friction wear became a main mode of wear, while adhesive wear was reduced. The above results suggested that the addition of Yb₂O₃ powder improved the plastic deformation resistance of the cladding layer.