Metal surface high-energy beam additive preparation method

Abstract

The invention discloses a metal surface high-energy beam additive preparation method. The method comprises the steps that weighed composite material powder is dried in a vacuum drying box; mixing the vacuum-dried composite material powder with paraffin in proportion to form a composite material coating; the composite material coating preloaded in the container is extruded through an extruder, an induction heater is arranged at the front end of an outlet of the extruder, paraffin in the composite material coating is gasified through the induction heater, and composite material powder in the composite material coating is preheated by the induction heater and then coated to the surface of the metal workpiece; the surface of the metal workpiece which is coated with the composite material powder and passes through the operation in the step C is subjected to material adding operation through high-energy beam irradiation; the method has the advantages that the energy consumption of heating and melting of a high-energy beam is saved, a more excellent additive layer is formed, the thermal stress and the deformation are reduced, and the technical obstacles existing in direct powder feeding and welding wire feeding are avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of surface treatment, and particularly to a method for additive manufacturing of high-energy beam on a metal surface. Background Art

[0002] The metal surface additive manufacturing technology is an important means to improve the surface properties of metal workpieces such as surface hardness, wear resistance, and corrosion resistance. This technology irradiates high-energy beams such as lasers, plasmas, and argon arcs on the surface of parts to form a molten pool, and at the same time feeds materials into the molten pool, and an additional layer is formed after solidification. Currently, it has been applied to the surfaces of steel, nickel-based alloys, cobalt-based alloys, copper alloys, titanium alloys, and aluminum alloys. The additive technology can improve surface properties, and multi-layer additive manufacturing can directly manufacture complex parts. Common cladding materials include alloy powders, alloy welding wires, etc. Therefore, in the existing technology, the implementation methods of high-energy beam additive manufacturing mainly involve prefabricating materials into welding wires or powders and feeding them using wire feeders or powder feeders.

[0003] The patent document of CN118704002A discloses a laser repair technology for surface damage of steel railway switches and its application. The rail laser additive manufacturing method includes grinding and preheating the surface of the steel railway switch, and then performing laser cladding and heat treatment to complete the laser repair of the surface damage of the steel railway switch. Iron-based alloy powder with a particle size of 53 - 150 μm is used for laser cladding, and the mass percentages of various elements are specific to improve the cold resistance and wear resistance of the steel railway switch.

[0004] The patent document of CN117965995A discloses an alloy powder, preparation, and repair method for repairing the inner surface of a servomotor cylinder. Laser cladding is carried out using the alloy powder. The alloy powder contains specific weight percentages of elements such as Si, Cr, Mn, Mo, Co, and Fe, and the particle size is 50 - 150 μm. The repair method includes oil stain treatment, scratch treatment, envelope milling, powder drying treatment, laser cladding repair, and grinding of the repaired surface on the inner surface of the cylinder.

[0005] The patent document of CN117020225A discloses an additive manufacturing method for a gradient composite coating on the surface of a thermal pipeline. It also uses powder for laser cladding on the metal surface to prepare a gradient composite coating on the surface of the thermal pipeline to improve the corrosion and wear resistance. The powder includes stainless steel powder, SiC powder, and BC powder.

[0006] The patent document of CN116970944A discloses a surface modification method for aluminum alloy. Cobalt-chromium-tungsten-based alloy powder is used as the cladding material, and laser cladding is carried out on the preheated aluminum alloy surface to improve the surface properties of the aluminum alloy. The laser cladding conditions include specific laser output power, scanning speed, spot diameter, and powder feeding amount, and the preheating temperature of the aluminum alloy is 130 - 150 °C.

[0007] In the above-mentioned patent, the main powder feeding methods for additive manufacturing by the powder feeder are: side-axis powder feeding, coaxial circumferential powder feeding, and central powder feeding. However, there are common problems such as: the cladding powder is blown away, reducing the powder utilization rate and the cladding efficiency, and there are also problems such as easy powder clogging and high maintenance costs. Moreover, due to the instability of the powder feeding method, the quality of the cladding layer fluctuates greatly, and it is difficult to achieve a uniform and consistent cladding effect, which poses an obstacle to improving the surface performance of the workpiece. When using various wear-resistant welding wires for additive manufacturing, it is limited by the filling rate and drawing rate parameter windows in the wire drawing process during the manufacturing process of the welding wire. The filling content of the wear-resistant phase of the developed welding wire material cannot break through the existing parameter windows, and it is impossible to further improve the surface performance of the workpiece.

[0008] In summary, there are some common problems in the existing metal surface additive manufacturing methods in practical applications, which limit the improvement of the cladding effect and the expansion of the application range. Therefore, it is necessary to develop a new feeding method to achieve more efficient, more economical, and more stable metal surface additive manufacturing. Summary of the Invention

[0009] Based on the problems in the prior art, the technical problem to be solved by the present invention is to provide a high-energy beam additive manufacturing method for metal surfaces that does not use a wire feeder or a powder feeder to feed materials into the molten pool.

[0010] The technical solution adopted by the present invention to solve the above technical problems is: a high-energy beam additive manufacturing method for metal surfaces, comprising the following steps:

[0011] Step A: Drying the weighed composite material powder in a vacuum drying oven;

[0012] Step B: Mixing the vacuum-dried composite material powder with paraffin wax in a certain proportion to form a composite material coating;

[0013] Step C: Extruding the composite material coating pre-loaded in a container through an extruder. An induction heater is provided at the front end of the outlet of the extruder. The induction heater vaporizes the paraffin wax in the composite material coating, and the composite material powder in the composite material coating is preheated by the induction heater and then coated on the surface of the metal workpiece;

[0014] Step D: Performing additive manufacturing on the surface of the metal workpiece coated with the composite material powder through the operation of Step C by irradiating with a high-energy beam.

[0015] The preferred technical solution adopted by the present invention to solve the above technical problems is: Step C is carried out in a protective gas atmosphere, and the protective gas is any one of argon, nitrogen, and carbon dioxide.

[0016] The preferred technical solution adopted by the present invention to solve the above technical problems is: The composite powder in step A is a metal matrix composite material.

[0017] The preferred technical solution adopted by the present invention to solve the above technical problems is: The composite powder in step A is any one of an aluminum matrix composite material, a titanium matrix composite material, a nickel matrix composite material, an iron matrix composite material, and a silicon carbide ceramic matrix composite material.

[0018] The preferred technical solution adopted by the present invention to solve the above technical problems is: The weighed composite powder in step A is dried in a vacuum drying oven at 100 - 150 °C for 90 - 120 min.

[0019] The preferred technical solution adopted by the present invention to solve the above technical problems is: The composite powder after vacuum drying in step B is mixed with paraffin wax in a ratio of 1:(0.03 - 0.1).

[0020] The preferred technical solution adopted by the present invention to solve the above technical problems is: When extruding the composite material coating in step C, a fume purifier is used to collect and purify the gas generated during the gasification of paraffin wax.

[0021] The preferred technical solution adopted by the present invention to solve the above technical problems is: Before step C, the surface of the metal workpiece is cleaned to remove impurities, rust, and oil stains.

[0022] The preferred technical solution adopted by the present invention to solve the above technical problems is: In step B, the composite powder and paraffin wax are evenly stirred in a mixing barrel for 4 - 8 hours to achieve mixing.

[0023] The preferred technical solution adopted by the present invention to solve the above technical problems is: The high - energy beam irradiation in step D includes any one of laser, plasma, and argon arc high - energy beams.

[0024] Compared with the prior art, the advantages of the present invention are: By mixing the composite powder with paraffin wax for slurry extrusion, and using an induction heater at the opening of the extruder to heat the composite material coating formed by the mixture of the composite powder and paraffin wax, paraffin wax is gasified and at the same time the composite powder is pre - heated, saving the energy consumption for heating and melting by the high - energy beam, enabling it to fully react with the substrate to form a more excellent additive layer. In addition, it can also reduce the heat input to the substrate, thereby reducing thermal stress and deformation. This slurry feeding method avoids the problems of dust flying waste and easy powder clogging caused by direct powder feeding, reduces processing costs and improves operation efficiency, and also solves the technical obstacles existing in wire feeding. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described in detail below in conjunction with the accompanying drawings and preferred embodiments. However, those skilled in the art will appreciate that these drawings are only drawn for the purpose of explaining the preferred embodiments and should not be construed as limiting the scope of the present invention. In addition, unless otherwise specified, the drawings only schematically show the composition or structure of the described object and may include exaggerated displays, and the drawings are not necessarily drawn to scale.

[0026] Figure 1 It is a flowchart of a method for additive manufacturing of a high-energy beam on a metal surface in an embodiment. Detailed implementation manners

[0027] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Those skilled in the art will appreciate that these descriptions are only descriptive and exemplary and should not be construed as limiting the scope of protection of the present invention.

[0028] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the present invention is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present invention. The terms "first" and "second" are only for descriptive convenience and have no other directional meaning and should not be construed as limiting the present invention.

[0029] Embodiment 1:

[0030] This embodiment provides a method for additive manufacturing of a high-energy beam on a metal surface. Before preparation, the surface of the metal workpiece is usually cleaned to remove impurities, rust and oil.

[0031] As Figure 1 shown, the preparation method specifically includes the following steps:

[0032] Step A: Weigh the composite powder formed by the iron-based composite material, and perform drying treatment on the weighed composite powder in a vacuum drying oven at 120 °C for 100 minutes.

[0033] Step B: Weigh paraffin according to the formula table, and uniformly stir the composite powder dried in vacuum in Step A and paraffin at a ratio of 100:3 in a mixing barrel for 8 hours to achieve mixing, forming a composite coating, and preloading the mixed composite coating in a container such as a coating barrel for later use.

[0034] Step C: Under the atmosphere of any one of argon, nitrogen, and carbon dioxide as the protective gas, the composite material coating pre-loaded in the container is extruded through an extruder. The extruder utilizes the piston principle to extrude the composite material coating in the container from the preset outlet at the front end under high pressure. The shape and size of the outlet can be customized specifically according to the metal workpiece and process requirements to ensure the thickness and size of the extruded composite material coating.

[0035] An induction heater is provided at the front end of the outlet of the extruder. The induction heater heats the extruded coating to vaporize the paraffin mixed with the composite material powder in the composite material coating, and at the same time preheats the composite material powder. The composite material powder in the composite material coating is coated on the surface of the metal workpiece after being preheated by the induction heater. Preferably, in this step, a fume purifier is also used to collect and purify the gas generated when the paraffin is vaporized.

[0036] Step D: Laser high-energy beam irradiation is used to perform an additive operation on the surface of the metal workpiece coated with the composite material powder through the operation of Step C.

[0037] In this embodiment, by mixing the composite material powder with paraffin and extruding the slurry, the filling rate problem restricted by the wire drawing process in the wire production process is solved, the filling amount of the strengthening phase is increased, breaking through the maximum value of 40% of the existing process parameters, and the performance of each additive layer can be greatly improved. At the same time, the problem that the flux cored wire is affected by factors such as environmental humidity during the powder filling process of the wire drawing process, resulting in the appearance of pores in the additive layer, is solved. At the same time, the problems of dust splash waste and easy powder blockage caused by direct powder feeding are also avoided, reducing the processing cost and improving the operation efficiency.

[0038] In this embodiment, the induction heater at the opening of the extruder is used to heat the composite material coating formed by mixing the composite material powder with paraffin. After the composite material coating reaches a certain temperature, it is then sent to the molten pool. During this process, the paraffin is vaporized, and the preheated composite material powder can save the energy consumption for heating and melting it by the high-energy beam, enabling it to fully react with the substrate to form a better additive layer. After saving the above-mentioned part of the energy, the heat input to the substrate can be reduced, thereby reducing the thermal stress and deformation amount.

[0039] Embodiment Two:

[0040] This embodiment adjusts the details such as the materials used and process parameters on the basis of Embodiment One. Only the differences between this embodiment and Embodiment One will be elaborated below, and the same parts will not be repeated.

[0041] In this embodiment,

[0042] The preparation method specifically includes the following multiple steps: This embodiment provides a method for high-energy beam additive manufacturing on the metal surface.

[0043] Step A: Weigh the composite powder formed by the iron-based composite material, and perform drying treatment on the weighed composite powder in a vacuum drying oven at 100 °C for 150 minutes.

[0044] Step B: Weigh paraffin according to the formula table, and uniformly stir the composite powder after vacuum drying in Step A and paraffin at a ratio of 10:1 in a mixing barrel for 4 hours to achieve mixing, forming a composite coating, and pre-install the mixed composite coating in a container such as a paint bucket for standby.

[0045] Step C: Under an atmosphere of any one of the protective gases argon, nitrogen, and carbon dioxide, extrude the composite coating pre-installed in the container through an extruder. The extruder utilizes the piston principle to extrude the composite coating in the container from the preset outlet at the front end under high pressure. The shape and size of the outlet can be customized specifically according to the metal workpiece and process requirements to ensure the thickness and size of the extruded composite coating.

[0046] An induction heater is provided at the front end of the outlet of the extruder. The induction heater heats the extruded coating to vaporize the paraffin mixed with the composite powder in the composite coating, and at the same time preheats the composite powder. The composite powder in the composite coating is preheated by the induction heater and then coated on the surface of the metal workpiece. Preferably, in this step, a fume purifier is also used to collect and purify the gas generated when the paraffin is vaporized.

[0047] Step D: Perform additive manufacturing on the surface of the metal workpiece coated with the composite powder through the operation of Step C by irradiating with a high-energy laser beam.

[0048] Example 3:

[0049] This example adjusts the details such as the materials used and process parameters on the basis of Example 1. Only the differences between this example and Example 1 are described below, and the same parts are not repeated.

[0050] In this example,

[0051] The preparation method specifically includes the following multiple steps: This example provides a method for additive manufacturing on a metal surface with a high-energy laser beam.

[0052] Step A: Weigh the composite powder formed by the iron-based composite material, and perform drying treatment on the weighed composite powder in a vacuum drying oven at 150 °C for 90 minutes.

[0053] Step B: Weigh paraffin according to the formula table. Mix the composite material powder after vacuum drying in Step A with paraffin at a ratio of 25:1 in a mixing barrel and stir evenly for 6 hours to achieve mixing, forming a composite material coating. Then preload the mixed composite material coating in a container such as a paint bucket for later use.

[0054] Step C: Under an atmosphere of any one of the protective gases argon, nitrogen, and carbon dioxide, extrude the composite material coating preloaded in the container through an extruder. The extruder utilizes the piston principle to extrude the composite material coating in the container from a preset outlet at the front end under high pressure. The shape and size of the outlet can be customized specifically according to the metal workpiece and process requirements to ensure the thickness and size of the extruded composite material coating. An induction heater is provided at the front end of the outlet of the extruder, and the induction heater heats the extruded coating to vaporize the paraffin mixed with the composite material powder in the composite material coating, and at the same time preheats the composite material powder. The composite material powder in the composite material coating is preheated by the induction heater and then coated on the surface of the metal workpiece. Preferably, in this step, a fume purifier is simultaneously used to collect and purify the gas generated when the paraffin is vaporized.

[0055] Step D: Perform an additive operation on the surface of the metal workpiece coated with the composite material powder through the operation in Step C by irradiating with a high-energy laser beam.

[0056] Comparative examples:

[0057] In Comparative Example 1 to Comparative Example 3, a feeder is used to directly send the composite material powder dried in a vacuum drying oven to the surface of the metal workpiece.

[0058] Among them, Comparative Example 1 includes the following steps. Step S1: Weigh the composite material powder formed by the iron-based composite material, and perform a drying treatment on the weighed composite material powder in a vacuum drying oven at 120 °C for 100 min. Step S2: Use a powder feeder to send the composite material powder obtained in Step S1 to the surface of the metal workpiece and perform an additive operation through a high-energy laser beam. The dilution rate is reduced by 50%, the porosity and inclusions are reduced by 30%, the density of the reinforcing phase is increased by 1 time, and the anti-friction and wear resistance performance is increased by 2 times.

[0059] Among them, Comparative Example 2 includes the following steps. Step S1: Weigh the composite material powder formed by the iron-based composite material, and perform a drying treatment on the weighed composite material powder in a vacuum drying oven at 100 °C for 150 min. Step S2: Use a powder feeder to send the composite material powder obtained in Step S1 to the surface of the metal workpiece and perform an additive operation through a high-energy laser beam. The dilution rate is reduced by 44%, the porosity and inclusions are reduced by 26%, the density of the reinforcing phase is increased by 1 time, and the anti-friction and wear resistance performance is increased by 2 times.

[0060] Among them, Comparative Example 3 includes the following steps. Step S1: Weigh the composite powder formed by the iron-based composite material, and dry the weighed composite powder in a vacuum drying oven at 150°C for 90 minutes. Step S2: Use a powder feeder to send the composite powder obtained in Step S1 to the surface of the metal workpiece for additive manufacturing through a high-energy laser beam. The dilution rate is reduced by 50%, the porosity and inclusions are reduced by 30%, the density of the reinforcing phase is doubled, and the anti-friction and wear resistance performance is doubled.

[0061] It should be noted that under the inventive concept of the present invention, the composite powder includes, but is not limited to, any one of metal matrix composites such as aluminum-based composites, titanium-based composites, nickel-based composites, and iron-based composites. The high-energy beam irradiation is not limited to lasers, and can also be ions, argon arcs, etc.

[0062] The above introduces a method for additive manufacturing of a metal surface by a high-energy beam. In this article, specific examples are used to elaborate on the principle and implementation method of the present invention. The description of the above embodiments is only used to help understand the present invention and its core idea. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing metal surface with high energy beam additive, characterized in that The steps include: Step A: drying the weighed composite material powder in a vacuum drying oven; Step B: mixing the composite material powder after vacuum drying with paraffin wax in proportion to form a composite material coating; Step C: extruding the composite material coating pre-installed in a container through an extruder, an induction heater is provided at the front end of the outlet of the extruder, the induction heater vaporizes the paraffin wax in the composite material coating, and the composite material powder in the composite material coating is preheated by the induction heater and then coated on the surface of the metal workpiece; Step D: high energy beam irradiation is used to perform additive manufacturing on the surface of the metal workpiece coated with the composite material powder in step C.

2. A method for preparing a metal surface by high-energy beam additive according to claim 1, characterized in that: Step C is carried out under a protective gas atmosphere, wherein the protective gas is any one of argon, nitrogen and carbon dioxide.

3. The method for preparing a metal surface by high-energy beam additive according to claim 1, characterized in that: The composite material powder in step A is a metal-based composite material.

4. The method for preparing a metal surface by high-energy beam additive according to claim 1, characterized in that: The composite material powder in step A is any one of an aluminum-based composite material, a titanium-based composite material, a nickel-based composite material, and an iron-based composite material.

5. The method for preparing a metal surface by high-energy beam additive according to claim 1, characterized in that: The weighed composite material powder in step A is dried in a vacuum drying oven at 100-150° C. for 90-120 minutes.

6. The method for high-energy beam additive manufacturing of metal surface according to claim 1, characterized in that: The composite material powder after vacuum drying in step B is mixed with paraffin in a ratio of 1: (0.03-0.1).

7. The method for high-energy beam additive manufacturing of metal surface according to claim 1, characterized in that: In step C, while the composite material coating is extruded, a smoke purifier is used to collect and purify the gas generated when the paraffin is gasified.

8. The method for high-energy beam additive manufacturing of metal surface according to claim 1, characterized in that: Before step C, the surface of the metal workpiece is cleaned to remove impurities, rust and oil.

9. The method for preparing a metal surface by high-energy beam additive according to claim 6, characterized in that: In step B, the composite material powder and paraffin are mixed in a mixing barrel by stirring at a constant speed for 4-8 hours.

10. The method for high-energy beam additive manufacturing of metal surface according to claim 1, characterized in that: The high energy beam irradiation in step D includes any one of laser, plasma, and argon arc high energy beam.

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