WO2021103120A1 - Plasma cladded metal coating with high wear resistance and corrosion resistance and preparation method therefor - Google Patents

Abstract

The present invention relates to a plasma cladded metal coating with high wear resistance and corrosion resistance and a preparation method therefor. The coating is prepared from a zirconium-containing nickel-based tungsten carbide powder, wherein the zirconium-containing nickel-based tungsten carbide powder is composed of a spherical tungsten carbide and a zirconia-containing nickel-based alloy binding phase, wherein the volume percentage of the spherical tungsten carbide is 30%-40%, and the volume percentage of the nickel-based alloy binding phase is 60%-70%, and the nickel-based alloy binding phase comprises, in percentages by mass, 1%-5% of silicon, 3%-5% of boron, 5%-10% of carbon, 0.5%-1.5% of zirconium, 5%-10% of chromium, 3%-5% of iron, and the balance being nickel. The advantages of the present invention lie in that in the present invention, by adding a trace amount of a zirconia powder to the nickel-based tungsten carbide powder, the plasma cladded metal coating is refined, fine cracks of the metal coating are reduced, the holding force of the nickel-based binding phase in the metal coating relative to the tungsten carbide particles is improved, the wear resistance of the metal coating is improved, and finally a metal coating with high wear resistance and corrosion resistance is obtained.

Description

High wear resistance and corrosion resistance plasma cladding metal coating and preparation method thereof Technical field

The invention belongs to the technical field of surface coatings, and particularly relates to a highly wear-resistant and corrosion-resistant plasma cladding metal coating and a preparation method thereof.

Background technique

With the increasing poverty of terrestrial mineral resources and the deepening of human understanding of the ocean, the seabed is becoming the next area for humans to march into the deep seabed with extremely rich mineral resources. In order to obtain the rich mineral resources of the seabed, deep-sea mining technology is very important. This technology is that the concentrator collects the nodules that exist in a large area of the ocean floor, is deslimed, crushed, and transported to the relay silo of the underwater intermediate platform through a hose, and then the nodules are fed into by the feeder The main pipeline of the lifting pump is lifted to the ocean surface mining ship by the lifting pump. At this time, the service life of the lifting pump blades in the lifting system is very important.

In order to prolong the service life of the pump blades, it is considered to cladding wear-resistant and corrosion-resistant coatings on the surface of the pump blades. When the pump blades work in seawater environment, the cladding coating on the surface must have corrosion resistance. As we all know, the coating made of nickel-based self-fluxing powder and tungsten carbide hard particles has higher hardness, better wear resistance and corrosion resistance, and becomes the best choice for the preparation of pump blade coatings.

At present, the methods for preparing nickel-based tungsten carbide coatings mainly include plasma spraying, laser cladding and plasma cladding technologies. Among them, the metal coating prepared by plasma spraying and the substrate belong to a mechanical combination, and the tungsten carbide particles are very easy to fall off; due to the large energy and heat concentration during laser cladding, the residual stress of the nickel-based tungsten carbide coating is relatively large, which is extremely easy Produce crack defects. These two technologies are limited in practical engineering applications. Plasma cladding technology compresses the arc into a plasma arc, and uses a small current. Compared with laser cladding technology, the heat is small, the thermal stress of the cladding metal coating is small, the transition zone formed is deeper, and the atomic bonding force is strong. ; At the same time, the equipment is inexpensive and easy to operate. Therefore, plasma cladding technology is considered to be a more suitable technology for preparing nickel-based tungsten carbide metal coatings, but in the actual preparation process, it is found that there are still micro cracks on the surface of the metal coating.

Summary of the invention

The technical problem to be solved by the present invention is to provide a high wear-resistant and corrosion-resistant plasma cladding metal coating that can reduce micro cracks on the surface of the metal coating and improve the wear resistance of the metal coating and a preparation method thereof.

In order to solve the above technical problems, the technical scheme of the present invention is: a high wear-resistant and corrosion-resistant plasma cladding metal coating. The innovation is that the coating is prepared from zirconium-containing nickel-based tungsten carbide powder, which contains Zirconium-nickel-based tungsten carbide powder is composed of spherical tungsten carbide and zirconia-containing nickel-based alloy binder phase. The volume percentage of spherical tungsten carbide is 30%-40%, and the volume percentage of nickel-based alloy binder phase is 60%- 70%; The nickel-based binder phase includes 1 to 5% of silicon, 3 to 5% of boron, 5 to 10% of carbon, 0.5 to 1.5% of zirconium, and 5 to 10% of Chromium, 3 to 5% iron, the balance is nickel.

Further, the spherical tungsten carbide is _{a spherical particle composed of WC and W 2} C with a layered feather-like eutectic structure.

Further, the nickel-based binder phase includes Ni ₃ Si phase and Cr ₃ Ni ₂ phase.

A method for preparing the above-mentioned high wear-resistance and corrosion-resistant plasma cladding metal coating is innovative in that: the preparation method includes the following steps:

Step 1: Use the mechanical method of turning and polishing to remove the oxide of the substrate until the metallic luster is exposed, and then clean it with a metal detergent;

Step 2: Heat the substrate before plasma cladding treated in step 1 in the furnace at 400-450°C for 2-3 hours, and place the zirconia-containing nickel-based tungsten carbide powder in a drying cabinet at 140-160°C for heat preservation 2 -5h;

Step 3: Pour the dried zirconium-containing nickel-based tungsten carbide powder into the powder feeder of the plasma cladding equipment, turn on the power switch of the plasma arc welding machine, loosen the gas valve, and send in powder gas, ion gas and shielding gas. Adjust the process parameters, and finally adjust the position of the substrate and the welding torch. The welding torch is perpendicular to the substrate and the distance to the substrate is 8-10mm. After checking it is correct, turn on the arc switch to start the cladding process. The high temperature generated by the plasma arc will The alloy powder and the surface of the substrate are rapidly heated and melted, mixed, and diffused together. With the relative movement of the arc and the workpiece, the liquid alloy is cooled after the plasma beam leaves to form a high-performance alloy coating;

Step 4: After the ion cladding in step 3 is completed, the metal coating test piece is slowly cooled to room temperature in vermiculite powder, and then appropriate sandblasting or polishing is performed to remove a small amount of oxidized slag on the surface.

Further, the adjustment process parameters in the step 3 specifically include an ion gas flow rate of 1.8 to 2.2 L/min, a powder feeding rate of 14 to 16 g/min, a current of 75 to 85 A, and a cladding rate of 2 to 4 mm/s.

The advantages of the present invention are: the high wear-resistant and corrosion-resistant plasma cladding metal coating of the present invention and the preparation method thereof, by adding a small amount of zirconia powder to the nickel-based tungsten carbide powder, the plasma cladding metal coating is refined and reduced The fine cracks of the metal coating improve the holding power of the nickel-based bond relative to the tungsten carbide particles in the metal coating, improve the wear resistance of the metal coating, and finally obtain a highly wear-resistant and corrosion-resistant metal coating.

Description of the drawings

The present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

Fig. 1 is a schematic diagram of the micro morphology of the high wear-resistant and corrosion-resistant metal coating of Example 3 of the present invention.

Detailed ways

The following embodiments may enable those skilled in the art to understand the present invention more comprehensively, but they do not limit the present invention to the scope of the described embodiments.

Example 1

In this embodiment, the method for preparing a highly wear-resistant and corrosion-resistant plasma cladding metal coating includes the following steps:

Step 1: Use the mechanical method of turning and polishing to remove the oxide of the substrate until the metallic luster is exposed, and then clean it with a metal detergent;

Step 2: Heat the substrate before plasma cladding treated in step 1 in a furnace at 400-450℃ for 2-3h, and place the zirconia-containing nickel-based tungsten carbide powder in a drying cabinet at 140-160℃ 2-5h, where the Si content in the nickel-based tungsten carbide powder containing zirconia is 2.12%, the B content is 1.52%, the Cr content is 8.63%, the Fe content is 2.24%, the Zr content is 0.5%, and the W content is 33.42 %, Ni is the balance. The diameter of spherical tungsten carbide is 50～150μm;

Step 3: Pour the dried zirconia-containing nickel-based tungsten carbide powder into the powder feeder of the plasma cladding equipment, turn on the power switch of the plasma arc welding machine, loosen the gas valve, and send in powder gas, ion gas and shielding gas , Adjust the process parameters: ion gas flow rate is 2.0L/min, powder feeding rate is 15g/min, current is 80A, cladding rate is 3mm/s, finally adjust the position of the substrate and welding gun, the welding gun is perpendicular to the substrate, The distance to the substrate is 8-10mm. After the inspection is correct, the arc switch is turned on to start the cladding process. The high temperature generated by the plasma arc will quickly heat the alloy powder and the substrate surface and melt, mix, and diffuse together. The relative movement of the workpiece, the liquid alloy cools after the plasma beam leaves, forming a high-performance alloy coating;

Step 4: After the ion cladding in step 3 is completed, the metal coating test piece is slowly cooled to room temperature in vermiculite powder, and then appropriate sandblasting or polishing is performed to remove a small amount of oxidized slag on the surface.

Example 2

In this embodiment, the method for preparing a highly wear-resistant and corrosion-resistant plasma cladding metal coating includes the following steps:

Step 1: Use the mechanical method of turning and polishing to remove the oxide of the substrate until the metallic luster is exposed, and then clean it with a metal detergent;

Step 2: Heat the substrate before plasma cladding treated in step 1 in the furnace at 400-450°C for 2-3 hours, and place the zirconia-containing nickel-based tungsten carbide powder in a drying cabinet at 140-160°C for heat preservation 2 -5h, where the Si content in the nickel-based tungsten carbide powder containing zirconia is 2.12%, the B content is 1.52%, the Cr content is 8.63%, the Fe content is 2.24%, the Zr content is 0.7%, and the W content is 33.42% , Ni is the margin. The diameter of spherical tungsten carbide is 50～150μm;

Step 3: Pour the dried zirconia-containing nickel-based tungsten carbide powder into the powder feeder of the plasma cladding equipment, turn on the power switch of the plasma arc welding machine, loosen the gas valve, and send in powder gas, ion gas and shielding gas , Adjust the process parameters: ion gas flow rate is 2.0L/min, powder feeding rate is 15g/min, current is 80A, cladding rate is 3mm/s, finally adjust the position of the substrate and welding gun, the welding gun is perpendicular to the substrate, The distance to the substrate is 8-10mm. After the inspection is correct, the arc switch is turned on to start the cladding process. The high temperature generated by the plasma arc will quickly heat the alloy powder and the substrate surface and melt, mix, and diffuse together. The relative movement of the workpiece, the liquid alloy cools after the plasma beam leaves, forming a high-performance alloy coating;

Step 4: After the ion cladding in step 3 is completed, the metal coating test piece is slowly cooled to room temperature in vermiculite powder, and then appropriate sandblasting or polishing is performed to remove a small amount of oxidized slag on the surface.

Example 3

In this embodiment, the method for preparing a highly wear-resistant and corrosion-resistant plasma cladding metal coating includes the following steps:

Step 1: Use the mechanical method of turning and polishing to remove the oxide of the substrate until the metallic luster is exposed, and then clean it with a metal detergent;

Step 2: Heat the substrate before plasma cladding treated in step 1 in the furnace at 400-450°C for 2-3 hours, and place the zirconia-containing nickel-based tungsten carbide powder in a drying cabinet at 140-160°C for heat preservation 2 -5h, in which, the content of Si in the nickel-based tungsten carbide powder containing zirconia is 2.12%, the content of B is 1.52%, the content of Cr is 8.63%, the content of Fe is 2.24%, the content of Zr is 1%, and the content of W is 33.42% , Ni is the margin. The diameter of spherical tungsten carbide is 50～150μm;

Step 3: Pour the dried zirconia-containing nickel-based tungsten carbide powder into the powder feeder of the plasma cladding equipment, turn on the power switch of the plasma arc welding machine, loosen the gas valve, and send in powder gas, ion gas and shielding gas , Adjust the process parameters: ion gas flow rate is 2.0L/min, powder feeding rate is 15g/min, current is 80A, cladding rate is 3mm/s, finally adjust the position of the substrate and welding gun, the welding gun is perpendicular to the substrate, The distance to the substrate is 8-10mm. After the inspection is correct, the arc switch is turned on to start the cladding process. The high temperature generated by the plasma arc will quickly heat the alloy powder and the substrate surface and melt, mix, and diffuse together. The relative movement of the workpiece, the liquid alloy cools after the plasma beam leaves, forming a high-performance alloy coating;

Step 4: After the ion cladding in step 3 is completed, the metal coating test piece is slowly cooled to room temperature in vermiculite powder, and then appropriate sandblasting or polishing is performed to remove a small amount of oxidized slag on the surface.

Example 4

In this embodiment, the method for preparing a highly wear-resistant and corrosion-resistant plasma cladding metal coating includes the following steps:

Step 1: Use the mechanical method of turning and polishing to remove the oxide of the substrate until the metallic luster is exposed, and then clean it with a metal detergent;

Step 2: Heat the substrate before plasma cladding treated in step 1 in the furnace at 400-450°C for 2-3 hours, and place the zirconia-containing nickel-based tungsten carbide powder in a drying cabinet at 140-160°C for heat preservation 2 -5h, where the Si content in the nickel-based tungsten carbide powder containing zirconia is 2.12%, the B content is 1.52%, the Cr content is 8.63%, the Fe content is 2.24%, the Zr content is 1.2%, and the W content is 33.42% , Ni is the margin. The diameter of spherical tungsten carbide is 50～150μm;

Step 3: Pour the dried zirconia-containing nickel-based tungsten carbide powder into the powder feeder of the plasma cladding equipment, turn on the power switch of the plasma arc welding machine, loosen the gas valve, and send in powder gas, ion gas and shielding gas , Adjust the process parameters: ion gas flow rate is 2.0L/min, powder feeding rate is 15g/min, current is 80A, cladding rate is 3mm/s, finally adjust the position of the substrate and welding gun, the welding gun is perpendicular to the substrate, The distance to the substrate is 8-10mm. After the inspection is correct, the arc switch is turned on to start the cladding process. The high temperature generated by the plasma arc will quickly heat the alloy powder and the substrate surface and melt, mix, and diffuse together. The relative movement of the workpiece, the liquid alloy cools after the plasma beam leaves, forming a high-performance alloy coating;

Step 4: After the ion cladding in step 3 is completed, the metal coating test piece is slowly cooled to room temperature in vermiculite powder, and then appropriate sandblasting or polishing is performed to remove a small amount of oxidized slag on the surface.

Example 5

In this embodiment, the method for preparing a highly wear-resistant and corrosion-resistant plasma cladding metal coating includes the following steps:

Step 1: Use the mechanical method of turning and polishing to remove the oxide of the substrate until the metallic luster is exposed, and then clean it with a metal detergent;

Step 2: Heat the substrate before plasma cladding treated in step 1 in the furnace at 400-450°C for 2-3 hours, and place the zirconia-containing nickel-based tungsten carbide powder in a drying cabinet at 140-160°C for heat preservation 2 -5h, where the Si content in the nickel-based tungsten carbide powder containing zirconia is 2.12%, the B content is 1.52%, the Cr content is 8.63%, the Fe content is 2.24%, the Zr content is 1.5%, and the W content is 33.42% , Ni is the margin. The diameter of spherical tungsten carbide is 50～150μm;

Step 3: Pour the dried zirconia-containing nickel-based tungsten carbide powder into the powder feeder of the plasma cladding equipment, turn on the power switch of the plasma arc welding machine, loosen the gas valve, and send in powder gas, ion gas and shielding gas , Adjust the process parameters: ion gas flow rate is 2.0L/min, powder feeding rate is 15g/min, current is 80A, cladding rate is 3mm/s, finally adjust the position of the substrate and welding gun, the welding gun is perpendicular to the substrate, The distance to the substrate is 8-10mm. After the inspection is correct, the arc switch is turned on to start the cladding process. The high temperature generated by the plasma arc will quickly heat the alloy powder and the substrate surface and melt, mix, and diffuse together. The relative movement of the workpiece, the liquid alloy cools after the plasma beam leaves, forming a high-performance alloy coating;

Step 4: After the ion cladding in step 3 is completed, the metal coating test piece is slowly cooled to room temperature in vermiculite powder, and then appropriate sandblasting or polishing is performed to remove a small amount of oxidized slag on the surface.

The mechanical properties of the metal coatings prepared in Examples 1-5 were tested, and the test results are shown in Table 1.

Table 1 shows the mechanical properties of the metal coatings prepared in each example:

To	Hardness (HRC)	Abrasion resistance	Corrosion resistance
Example 1	59	better	better
Example 2	60	better	better
Example 3	61	well	better
Example 4	60	better	better
Example 5	58	better	better

It can be seen from Table 1 that the nickel-based tungsten carbide metal coatings of the present invention have higher wear resistance and better corrosion resistance.

The microscopic morphology of the highly wear-resistant and corrosion-resistant metal coating of Example 3 was observed. As shown in Fig. 1, the structure of the nickel-based tungsten carbide coating was finer, the number of spherical tungsten carbide particles was large, and the metal coating had no fine cracks.

The basic principles and main features of the present invention and the advantages of the present invention have been shown and described above. Those skilled in the industry should understand that the present invention is not limited by the above-mentioned embodiments. The above-mentioned embodiments and the description only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have Various changes and improvements, these changes and improvements all fall within the scope of the claimed invention. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims (5)

1. A highly wear-resistant and corrosion-resistant plasma cladding metal coating, characterized in that: the coating is prepared from zirconium-containing nickel-based tungsten carbide powder, wherein the zirconium-containing nickel-based tungsten carbide powder is made of spherical tungsten carbide and oxide-containing The nickel-based alloy binder phase of zirconium is composed of 30%-40% by volume of spherical tungsten carbide and 60%-70% by volume of nickel-based alloy binder phase; In total, it includes 1 to 5% silicon, 3 to 5% boron, 5 to 10% carbon, 0.5 to 1.5% zirconium, 5 to 10% chromium, 3 to 5% iron, and the balance is nickel.
2. The high wear-resistant and corrosion-resistant plasma cladding metal coating of claim 1, wherein the spherical tungsten carbide is _{a spherical particle composed of WC and W 2} C with a feather-like eutectic structure.
3. The high wear-resistant and corrosion-resistant plasma cladding metal coating according to claim 1, wherein the nickel-based binder phase contains Ni ₃ Si phase and Cr ₃ Ni ₂ phase.
4. A method for preparing a highly wear-resistant and corrosion-resistant plasma cladding metal coating according to claim 1, wherein the preparation method comprises the following steps:

   Step 1: Use the mechanical method of turning and polishing to remove the oxide of the substrate until the metallic luster is exposed, and then clean it with a metal detergent;

   Step 2: Heat the substrate before plasma cladding treated in step 1 in the furnace at 400-450°C for 2-3 hours, and place the zirconia-containing nickel-based tungsten carbide powder in a drying cabinet at 140-160°C for heat preservation 2 -5h;

   Step 3: Pour the dried zirconium-containing nickel-based tungsten carbide powder into the powder feeder of the plasma cladding equipment, turn on the power switch of the plasma arc welding machine, loosen the gas valve, and send in powder gas, ion gas and shielding gas. Adjust the process parameters, and finally adjust the position of the substrate and the welding torch. The welding torch is perpendicular to the substrate and the distance to the substrate is 8-10mm. After checking it is correct, turn on the arc switch to start the cladding process. The high temperature generated by the plasma arc will The alloy powder and the surface of the substrate are rapidly heated and melted, mixed, and diffused together. With the relative movement of the arc and the workpiece, the liquid alloy is cooled after the plasma beam leaves to form a high-performance alloy coating;

   Step 4: After the ion cladding in step 3 is completed, the metal coating test piece is slowly cooled to room temperature in vermiculite powder, and then appropriate sandblasting or polishing is performed to remove a small amount of oxidized slag on the surface.
5. The method for preparing a highly wear-resistant and corrosion-resistant plasma cladding metal coating according to claim 4, wherein the process parameters adjusted in step 3 specifically include an ion gas flow rate of 1.8 to 2.2 L/min and a powder feeding rate It is 14～16g/min, the current is 75～85A, and the cladding rate is 2～4mm/s.

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