Self-fluxing cemented carbide spherical powder and its preparation method and application

Abstract

The present invention discloses a self-fluxing cemented carbide spherical powder and its preparation method and application, belonging to the field of powder preparation technology. The present invention mixes hard phase material, binder phase material and flux material and ball mills them, and then sintering them to obtain a self-fluxing cemented carbide blank; the self-fluxing cemented carbide blank is then subjected to arc micro-explosion, reduction and screening treatment to obtain a self-fluxing cemented carbide spherical powder. The obtained self-fluxing cemented carbide spherical powder has uniform composition and can be customized according to needs. It has a small particle size, high sphericity and low oxygen content, maintaining the original properties of the alloy, and can be used in the field of cladding processing. It is not easy to cause material segregation, and a cladding layer product with uniform composition can be prepared.

Description

Technical Field

[0001] The present invention relates to the technical field of powder preparation, in particular to a self-fluxing cemented carbide spherical powder and a preparation method and application thereof. Background Art

[0002] With the continuous development of industrial technology, the metal powder cladding application market is expanding rapidly, especially the application value of cemented carbide spherical powder. During the cladding process, it is often necessary to mix and formulate different types of metal powders according to the process requirements to achieve the final cladding effect.

[0003] The preparation methods of metal powders generally include: grinding and crushing, spray granulation drying, gas atomization, water atomization, plasma atomization, spheroidization, rotating electrode atomization, etc. The composition of the metal powders obtained by the above methods is limited by the composition of the raw materials, the composition is relatively simple, and the mixing between different metal powders is uneven. However, in the metal powder cladding process, it is usually necessary to mix and compound different types of metal powders, and then perform cladding processing to obtain the desired cladding layer product. If the mixing can only be performed by physical means such as stirring, it is difficult to ensure the uniformity of the composition of different types of metal powder materials. Moreover, the metal powder raw materials mixed by traditional stirring methods are prone to material segregation during the cladding process, which will directly affect the cladding process quality and thus affect the uniformity of the cladding layer product. Summary of the Invention

[0004] Based on this, the present invention mainly provides a self-fluxing cemented carbide spherical powder and its preparation method and application, to solve the technical problems of uneven mixing of raw material alloy metal powders, easy occurrence of material segregation, and uneven composition of the prepared cladding layer products when preparing cladding layer products through cladding processing.

[0005] To achieve the above object, the present invention provides a method for preparing self-fluxing cemented carbide spherical powder, comprising the following steps:

[0006] S10, mixing and ball-milling the hard phase material, the binder phase material, and the flux material, and then sintering to obtain a self-fluxing cemented carbide blank;

[0007] S20, connecting the self-fluxing cemented carbide blank to the positive electrode of a pulse power supply, connecting the graphite electrode to the negative electrode of the pulse power supply, applying a current between the positive electrode and the negative electrode of the pulse power supply to form an arc discharge, and forming a molten pit on the surface of the self-fluxing cemented carbide blank;

[0008] S30, introducing a high-pressure fluid between the positive electrode of the pulse power supply and the negative electrode of the pulse power supply, causing the high-pressure fluid to rush through the molten pit, causing the molten pit to explode and produce small droplets, and the small droplets are cooled to obtain primary self-fluxing cemented carbide spherical powder;

[0009] S40, reducing and sieving the primary self-fluxing cemented carbide spherical powder to obtain self-fluxing cemented carbide spherical powder.

[0010] In some embodiments of the present invention, the hard phase material includes at least one of WC, CrC, TiC, SiC, Al2O3, ZrO, AlN, TiN, TaN, BN, P3N5, Si3N4, and ZnB;

[0011] The bonding phase material includes at least one of Co, Ni, Fe, Cu, and Mo;

[0012] The flux material includes B and Si.

[0013] In some embodiments of the present invention, based on 100% of the total mass of the hard phase material, the adhesive phase material, and the flux material, the weight percentage of the hard phase material is greater than or equal to 50%; and / or the weight percentage of the flux material is less than or equal to 5%.

[0014] In some embodiments of the present invention, the high-pressure fluid includes high-pressure water flow and / or high-pressure gas.

[0015] In some embodiments of the present invention, the high-pressure fluid is a high-pressure gas, and the high-pressure gas includes high-pressure air, high-pressure nitrogen, high-pressure argon and / or high-pressure helium.

[0016] In some embodiments of the present invention, the sintering temperature is 1400° C. to 1500° C.; and the sintering time is greater than or equal to 6 hours.

[0017] In some embodiments of the present invention, in step S20, the applied current is above 300A.

[0018] In some embodiments of the present invention, in step S40, the primary self-fluxing cemented carbide spherical powder is subjected to a reduction treatment in a hydrogen atmosphere.

[0019] In some embodiments of the present invention, the screening method includes ultrasonic vibration screening treatment or airflow classification screening treatment.

[0020] The present invention also provides a self-fluxing cemented carbide spherical powder prepared by the method for preparing the self-fluxing cemented carbide spherical powder.

[0021] The beneficial effects that can be achieved by the present invention are:

[0022] The present invention compounds a hard phase material, a bonding phase material and a flux material, and obtains a self-fluxing cemented carbide blank through sufficient ball milling, mixing and sintering. The self-fluxing cemented carbide blank is used as a raw material in a cladding process and subjected to cladding treatment. Because the self-fluxing cemented carbide blank is obtained by pre-mixing different types of metal powders according to a certain weight ratio, a customized ratio can be made in the stage of preparing the self-fluxing hard metal spherical powder according to the component requirements of the cladding layer product, and then physical mixing is performed by ball milling, chemical mixing is performed in the sintering process, and finally arc micro-explosion treatment is performed, so that a self-fluxing cemented carbide spherical powder with uniform composition, high sphericity, lower cost and less surface oxide is easily obtained. When the self-fluxing cemented carbide spherical powder is applied to the cladding process, material segregation is not likely to occur, and a cladding layer product with uniform composition can be prepared. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. 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 the structures shown in these drawings without paying any creative work.

[0024] Figure 1 The figure is a schematic diagram of the preparation process of self-fluxing cemented carbide spherical powder according to one embodiment of the present invention.

[0025] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0026] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0028] In the present invention, descriptions such as "first" and "second" are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the technical features indicated. Therefore, features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions of various embodiments may be combined with each other, but this must be based on the fact that they can be implemented by a person of ordinary skill in the art. If the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0029] In cladding processes, such as laser cladding and plasma cladding, it is usually necessary to compound and mix different types of metal powders according to the needs, and then perform cladding treatment to obtain the desired product. For example, it is usually necessary to mix and compound hard phase metal powders and binder phase metal powders, and then perform cladding treatment to obtain the desired product. However, different types of metal powders are usually mixed by physical stirring before cladding treatment, which makes it difficult to achieve uniform mixing of different types of metals. Moreover, material segregation is easily generated during the cladding process, which will directly affect the quality of subsequent cladding processing and cause the cladding product to be prone to uneven composition.

[0030] In view of this, the present invention provides a method for preparing self-fluxing cemented carbide spherical powder, referring to Figure 1 , including the following steps:

[0031] S10, mixing and ball-milling the hard phase material, the binder phase material, and the flux material, and then sintering to obtain a self-fluxing cemented carbide blank;

[0032] S20, connecting the self-fluxing cemented carbide blank to the positive electrode of a pulse power supply, connecting the graphite electrode to the negative electrode of the pulse power supply, applying a current between the positive electrode and the negative electrode of the pulse power supply to form an arc discharge, and forming a molten pit on the surface of the self-fluxing cemented carbide blank;

[0033] S30, introducing a high-pressure fluid between the positive electrode of the pulse power supply and the negative electrode of the pulse power supply, causing the high-pressure fluid to rush through the molten pit, thereby causing the molten pit to produce small droplets, and the small droplets are cooled to obtain primary self-fluxing cemented carbide spherical powder;

[0034] S40, reducing and sieving the primary self-fluxing cemented carbide spherical powder to obtain self-fluxing cemented carbide spherical powder.

[0035] The present invention compounds a hard phase material, a binder phase material and a flux material, and obtains a self-fluxing cemented carbide blank through sufficient ball milling, mixing and sintering. The self-fluxing cemented carbide blank is used as a raw material in a metal powder cladding process and subjected to cladding treatment. Because the self-fluxing cemented carbide blank is a mixture of different types of metal powders in advance according to a certain weight ratio, a customized ratio can be made at the stage of preparing the self-fluxing hard metal spherical powder according to the component requirements of the cladding layer product, and then physical mixing is performed by mixed ball milling, chemical mixing is performed during the sintering process, and then arc micro-explosion treatment is performed. It is easy to obtain a self-fluxing cemented carbide spherical powder with uniform composition, high sphericity, lower cost and less surface oxide. The self-fluxing cemented carbide spherical powder is applied to the cladding process, and material segregation is not easy to occur, and a cladding layer product with uniform composition can be prepared.

[0036] In the present invention, the binder phase material is a common raw material in metal cladding processing. In the process of preparing self-fluxing cemented carbide billets, it can also enhance the bonding force between hard phase materials and improve the toughness and impact resistance of the alloy. The flux material can inhibit the growth of grains, which is conducive to obtaining finer grains and improving the strength and toughness of the self-fluxing cemented carbide spherical powder. In addition, the flux material can also improve the fluidity of the liquid phase during sintering, promote uniform mixing and densification of the alloy, and facilitate obtaining self-fluxing cemented carbide spherical powder with uniform composition.

[0037] In some embodiments, the hard phase material includes at least one of WC, CrC, TiC, SiC, Al2O3, ZrO, AlN, TiN, TaN, BN, P3N5, Si3N4, and ZnB, and the above types of hard phase materials have high wear resistance and hardness.

[0038] In some embodiments, the particle size of the hard phase material is 100 mm to 200 mm.

[0039] In some embodiments, the binder phase material includes at least one of Co, Ni, Fe, Cu, and Mo. The above types of binder phase materials can enhance the bonding force between hard phase materials, improve the toughness and impact resistance of the alloy, and also improve the sphericity of the self-fluxing cemented carbide powder.

[0040] In some embodiments, the particle size of the binder phase material is 100 mm to 200 mm.

[0041] In some embodiments, the flux material includes B and Si. The above types of flux materials can inhibit the growth of grains, which is conducive to obtaining finer grains and improving the strength and toughness of the self-fluxing cemented carbide spherical powder. In addition, the flux material can also improve the fluidity of the liquid phase during the sintering process, promote the uniform mixing and densification of the alloy, and facilitate obtaining a self-fluxing cemented carbide spherical powder with uniform composition.

[0042] In some embodiments, the flux material is B and Si, and the hard phase material includes WC and Co. In this embodiment, the flux material and the hard phase material are easy to mix evenly to obtain a uniformly mixed self-fluxing cemented carbide spherical powder, which is used to prepare cladding layer products. Material segregation is not likely to occur, and a uniform cladding layer product is easy to prepare, thereby improving the performance of the cladding layer product.

[0043] In some embodiments, the flux has a particle size of 100 mm to 200 mm.

[0044] In the present invention, the composition ratio of the hard phase material, the binder phase material and the flux material can be matched as required.

[0045] In some embodiments, based on 100% of the total mass of the hard phase material, the binder phase material, and the flux material, the weight percentage of the hard phase material is greater than or equal to 50%, which is beneficial to improving the hardness, wear resistance, compressive strength and thermal stability of the final product, the self-fluxing cemented carbide spherical powder, while obtaining better surface integrity and improving the sphericity. It is used as a raw material in laser cladding and plasma cladding processing, and it is easy to obtain a uniform cladding layer product.

[0046] In some embodiments, based on 100% of the total mass of the hard phase material, the binder phase material, and the flux material, the weight percentage of the flux material is less than or equal to 5%, which is beneficial to refine the grains and obtain grains with smaller particle size. At the same time, it improves the fluidity of the liquid phase during the sintering process, promotes uniform mixing and densification of the alloy, and is beneficial to obtain self-fluxing cemented carbide spherical powder with uniform composition. It is used as a raw material in laser cladding and plasma cladding processing. It is not easy to produce material segregation during the cladding process, and it is easy to prepare a uniform cladding layer product.

[0047] The present invention mixes a hard phase material, a binder phase material, and a flux material, and then performs sintering, arc micro-explosion, reduction, and screening treatments to obtain a self-fluxing cemented carbide spherical powder with less surface oxides. The self-fluxing cemented carbide spherical powder is applied to cladding processing, and material segregation is less likely to occur, so a cladding layer product with uniform composition can be prepared.

[0048] In some embodiments, the sintering temperature is 1400°C to 1500°C. Under the above temperature conditions, it is conducive to promoting the uniform mixing of hard phase materials, bonding phase materials, and flux materials, thereby obtaining a self-fluxing cemented carbide blank with uniform composition. The self-fluxing cemented carbide blank is subjected to arc micro-explosion, reduction, and screening treatment to obtain a self-soluble cemented carbide spherical powder with specific composition. The self-soluble cemented carbide spherical powder with specific composition is applied to laser cladding and plasma cladding processing. During the cladding process, material segregation is not easily produced, and a uniform cladding layer product is easy to prepare.

[0049] In some embodiments, the sintering time is greater than or equal to 6 hours, and can be 6 hours, 7 hours, 8 hours, etc.

[0050] In the present invention, step S20 generates arc discharge by applying current to form a molten pit on the surface of the self-fluxing cemented carbide, which facilitates the subsequent generation of small metal droplets by the impact of high-pressure fluid.

[0051] In some embodiments, before performing step S20, the self-fluxing cemented carbide blank is further cleaned and decontaminated. The specific cleaning and decontamination steps may be commonly used steps in the art and will not be described in detail here.

[0052] In some embodiments, the discharge current is greater than or equal to 300 A, which facilitates the formation of molten pits on the surface of the self-fluxing cemented carbide blank.

[0053] In some embodiments, the relative gap distance between the positive electrode of the pulse power supply and the negative electrode of the pulse power supply is 0.03 mm to 0.05 mm. Within the above gap distance range, it is conducive to accurately controlling the formation of the molten pit, and the arc is relatively stable, making the formation and maintenance of the molten pit more controllable, and helping to avoid excessive expansion or instability of the molten pit, thereby improving the composition uniformity and sphericity of the self-fluxing cemented carbide spherical powder obtained subsequently.

[0054] In the present invention, step S30 utilizes high-pressure fluid to impact the molten pit, which can cause the molten pit to produce small metal droplets. The metal droplets fly out of the molten zone and cool rapidly to obtain primary self-fluxing cemented carbide spherical powder.

[0055] In some embodiments, the high-pressure fluid includes high-pressure water flow and / or high-pressure gas. The impact of high-pressure water flow and high-pressure gas on the molten pit can quickly cool the metal droplets, help form a fine grain structure, and improve the strength, toughness and sphericity of the material. In addition, the deposition position and shape of the small droplets can be precisely controlled by precisely controlling the parameters of the high-pressure water flow and high-pressure gas, and it is not easy to react with the components in the self-fluxing cemented carbide to cause the generation of impurities.

[0056] In some embodiments, the high-pressure fluid is a high-pressure gas, which includes high-pressure air, high-pressure nitrogen, high-pressure argon and / or high-pressure helium. The above types of high-pressure gases are not easy to react with the components in the self-fluxing cemented carbide to cause impurities to be generated.

[0057] In some embodiments, the high-pressure fluid is a high-pressure water flow, the applied pressure is 1MPa~2MPa, and the flow rate is 50L / min~60L / min, which can promote the dispersion of small metal droplets and prevent the small metal droplets from sticking together before cooling to form self-fluxing cemented carbide spherical powder, thereby improving the sphericity of the self-fluxing cemented carbide spherical powder and controlling it to obtain a smaller particle size.

[0058] In some embodiments, step S30 is performed in an inert gas environment, such as an argon or nitrogen atmosphere, which can reduce oxidation of the metal droplets during the cooling process and provide a more uniform cooling environment, thereby helping to improve the sphericity of the metal powder.

[0059] In some embodiments, the relative horizontal movement of the negative electrode of the pulse power supply and the positive electrode of the pulse power supply can be adjusted to form numerous molten pits in sequence on the horizontal surface of the self-fluxing cemented carbide blank facing the electrode direction, and the flying material is prompted to become primary self-fluxing cemented carbide spherical powder. The material of a layer of the self-fluxing cemented carbide horizontal surface will be peeled off into countless initial self-fluxing cemented carbide spherical powders.

[0060] In some embodiments, the relative vertical movement of the negative electrode of the pulse power supply and the positive electrode of the pulse power supply can be adjusted so that the self-fluxing cemented carbide blank is peeled off layer by layer into countless initial self-fluxing cemented carbide spherical powders until the entire self-fluxing cemented carbide blank is completely peeled off, thereby improving the utilization rate of the material.

[0061] In some embodiments, the electrode is fed horizontally relative to the self-fluxing cemented carbide at a speed of 600 mm / min, and vertically relative to the self-fluxing cemented carbide at a speed of 0.5 mm / min.

[0062] In some embodiments, the primary self-fluxing cemented carbide spherical powder is washed before being processed in the subsequent step S40.

[0063] In some embodiments, the primary self-fluxing cemented carbide spherical powder is washed with an alcohol cleaning agent, such as ethanol.

[0064] In some embodiments, in step S40, the primary self-fluxing cemented carbide spherical powder is reduced in a hydrogen atmosphere to reduce the occurrence of side reactions and the generation of excessive impurities.

[0065] In some embodiments, the temperature range of the reduction treatment is 950°C to 1050°C.

[0066] In some embodiments, the reduction treatment time is 6 hours to 8 hours.

[0067] In some embodiments, the screening process includes ultrasonic vibration screening process or air flow classification screening process.

[0068] In some embodiments, the particle size of the self-fluxing cemented carbide spherical powder obtained by sieving is in the range of 50 μm to 150 μm.

[0069] The self-fluxing cemented carbide spherical powder of the present invention can be applied to cladding processing as a raw material for cladding processing, wherein the cladding processing includes plasma cladding processing and laser cladding processing.

[0070] The present invention also provides a cladding method comprising the steps of the method for preparing the self-fluxing cemented carbide spherical powder of the present invention, wherein the prepared self-fluxing cemented carbide spherical powder is used as a raw material and a cladding product is prepared by a cladding process. The cladding process includes a laser cladding process or a plasma cladding process, and the cladding product includes a cladding metal coating.

[0071] The cladding processing technology of the present invention can refer to the process flow and process parameters well known in the art, and use the self-fluxing cemented carbide blank of the present invention as the raw material in the cladding processing for cladding treatment. Because the self-fluxing cemented carbide blank is a mixture of different types of metal powders in a certain weight ratio in advance, it is possible to customize the proportions at the stage of preparing the self-fluxing hard metal spherical powder according to the composition requirements of the cladding layer product, and then perform physical mixing in ball milling, chemical mixing in the sintering process, and finally undergo arc micro-explosion treatment. It is easy to obtain self-fluxing cemented carbide spherical powder with uniform composition, high sphericity, lower cost and less surface oxide. When the self-fluxing cemented carbide spherical powder is applied to cladding processing, material segregation is not likely to occur, and a cladding layer product with uniform composition can be prepared.

[0072] The technical solutions of the present invention are further described in detail below in conjunction with specific embodiments. It should be understood that the following specific embodiments are only used to explain the present invention and are not used to limit the present invention.

[0073] Example 1

[0074] The preparation method of the self-fluxing cemented carbide spherical powder of this embodiment is as follows:

[0075] S10. Place the hard phase material, binder phase material, and flux material in a powder mixer according to Table 1 and mix them evenly. Then, place them in a ball mill and fully mill them to obtain a mixed powder. Place the mixed powder in a vacuum sintering furnace and sinter at 1400° C. for 6 h to form a self-fluxing cemented carbide blank.

[0076] S20. Connect the self-fluxing cemented carbide blank to the positive electrode of the pulse power supply, connect the graphite electrode to the negative electrode of the pulse power supply, and keep the relative gap distance between the positive electrode and the negative electrode of the pulse power supply at 0.03 mm. Apply a current of 320 A between the positive and negative electrodes, and generate arc discharge at the nearest surface of the self-fluxing cemented carbide to form a molten pit on the surface of the self-fluxing cemented carbide.

[0077] S30. Introduce pure water high-pressure fluid between the positive electrode and the negative electrode of the pulse power supply with a pressure of 1 MPa and a flow rate of 50 L / min. Locally strengthen the fluid to rush through the molten pit on the surface of the self-fluxing cemented carbide at high speed, causing the molten pit to explode and produce countless small droplets. The small droplets fly away from the molten area and are cooled by external low-temperature fluid to obtain primary self-fluxing cemented carbide spherical powder.

[0078] S40. The primary self-fluxing cemented carbide spherical powder is cleaned with ethanol, an alcohol cleaning agent, and then placed in a hydrogen atmosphere for reduction treatment. The reduction temperature is set to 950°C and the reduction time is 4 hours. The primary self-fluxing cemented carbide spherical powder that has completed the reduction treatment is placed on an air flow grading sieve for sieving to obtain three types of self-fluxing cemented carbide spherical powders with a particle size range of 50μm to 150μm, a particle size less than 50μm, and a particle size greater than 150μm.

[0079] Example 2

[0080] Example 2 Self-fluxing cemented carbide spherical powder was prepared by referring to the preparation method of Example 1, except that the composition of the self-fluxing cemented carbide was different, as shown in Table 1.

[0081] Example 3

[0082] Example 3 Self-fluxing cemented carbide spherical powder was prepared by referring to the preparation method of Example 1, except that the composition of the self-fluxing cemented carbide was different, as shown in Table 1.

[0083] Performance Testing

[0084] Using the self-fluxing cemented carbide spherical powders with a particle size of 50 μm to 150 μm obtained in Examples 1 to 3 as raw materials and an FV520B steel plate as a substrate, a 5 nm thick cladding alloy coating was prepared on the surface of the steel plate using a plasma cladding process. The plasma cladding process parameters were as follows: 99.99% pure argon was used as the shielding gas, the current was set to 100 A, the voltage was set to 50 V, and the feed rate was set to 5.5 g / min. A control group was also set up. In this control group, 60% WC, 5% CrC, and 30% Ni with a particle size of 50 μm to 150 μm were stirred and then used as raw materials to prepare a cladding alloy coating on the surface of the FV520B steel plate using the same plasma cladding process parameters.

[0085] The cladding alloy coatings obtained in Examples 1 to 3 and the control group were subjected to a thermal shock test. Specifically, the substrate containing the cladding alloy coating was placed in a furnace and heated to 500°C for 10 minutes, and then frozen in cold water at -20°C for 10 minutes. This test cycle was repeated 150 times to observe whether the cladding alloy coating had any fine cracks or cracks. The results are shown in Table 1.

[0086] Table 1

[0087]

[0088]

[0089] As can be seen from Table 1, the self-fluxing cemented carbide spherical powders of Examples 1 to 3 are used as raw materials. The various materials in the self-fluxing cemented carbide spherical powders are uniformly mixed. The cladding alloy coatings prepared by the plasma cladding process have good uniformity and good adhesion to the substrate. After thermal shock testing, the cladding alloy coatings are intact without fine cracks or cracks.

[0090] The control group used alloy powder obtained by physical mixing of 60% WC, 5% CrC and 30% Ni as raw material. Because physical mixing is difficult to achieve uniform mixing, problems such as material segregation are prone to occur when preparing the cladding alloy coating, which will cause the prepared cladding alloy coating to become uneven, thereby affecting the durability of the cladding alloy coating. Therefore, after the thermal shock test, the cladding alloy coating showed fine cracks.

[0091] It can be seen that the present invention compounds the hard phase material, the bonding phase material and the flux material, obtains the self-fluxing cemented carbide blank through sufficient ball milling mixing and sintering, and then prepares the self-fluxing soluble cemented carbide spherical powder by arc micro-explosion. The self-fluxing soluble cemented carbide spherical powder is used as the raw material in the cladding process. The cladding alloy coating obtained by the cladding process has uniform composition, strong bonding force and good durability. Moreover, according to the composition requirements of the cladding alloy coating, customized proportions can be performed at the stage of preparing the self-fluxing hard metal spherical powder, thereby achieving the purpose of customized design.

[0092] The above are only preferred embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for preparing self-fluxing cemented carbide spherical powder, characterized in that: The following steps are involved: S10, mixing a hard phase material, a binder phase material, and a flux material, ball-milling the mixture, and then sintering the mixture to obtain a self-fluxing cemented carbide blank; the sintering temperature is 1400° C. to 1500° C.; the sintering time is greater than or equal to 6 hours; the hard phase material comprises at least one of WC, CrC, TiC, SiC, Al2O3, ZrO, AlN, TiN, TaN, BN, P3N5, Si3N4, and ZnB; the binder phase material comprises at least one of Co, Ni, Fe, Cu, and Mo; the flux material comprises B and Si; based on 100% of the total mass of the hard phase material, the binder phase material, and the flux material, the weight percentage of the hard phase material is greater than or equal to 50%; the weight percentage of the flux material is less than or equal to 5%; S20, connecting the self-fluxing cemented carbide blank to the positive electrode of a pulse power supply, connecting the graphite electrode to the negative electrode of the pulse power supply, applying a current between the positive electrode and the negative electrode of the pulse power supply to form an arc discharge, and forming a molten pit on the surface of the self-fluxing cemented carbide blank; S30, introducing a high-pressure fluid between the positive electrode of the pulse power supply and the negative electrode of the pulse power supply, causing the high-pressure fluid to rush through the molten pit, thereby causing the molten pit to produce small droplets, and the small droplets are cooled to obtain primary self-fluxing cemented carbide spherical powder; S40, reducing and sieving the primary self-fluxing cemented carbide spherical powder to obtain self-fluxing cemented carbide spherical powder, using the self-fluxing cemented carbide spherical powder as a raw material for cladding processing, and obtaining a cladding alloy coating through cladding processing.

2. The method for preparing self-fluxing cemented carbide spherical powder according to claim 1, characterized in that: In step S20, the applied current is greater than 300A.

3. The method for preparing self-fluxing cemented carbide spherical powder according to claim 1, characterized in that: The high-pressure fluid includes high-pressure water and / or high-pressure gas.

4. The method for preparing self-fluxing cemented carbide spherical powder according to claim 3, characterized in that: The high-pressure fluid is a high-pressure gas, and the high-pressure gas includes high-pressure air, high-pressure nitrogen, high-pressure argon and / or high-pressure helium.

5. The method for preparing the self-fluxing cemented carbide spherical powder according to claim 1, characterized in that: In the step S40, the primary self-fluxing cemented carbide spherical powder is subjected to a reduction treatment in a hydrogen atmosphere; and / or, the screening method includes ultrasonic vibration screening treatment or airflow classification screening treatment.

6. A self-fluxing cemented carbide spherical powder, characterized in that: The self-fluxing cemented carbide spherical powder is prepared by the method for preparing the self-fluxing cemented carbide spherical powder according to any one of claims 1 to 5.

7. Use of the self-fluxing cemented carbide spherical powder according to claim 6 in the field of cladding processing.

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