Amorphous powder for laser cladding and method for preparing the same

Abstract

The application discloses an amorphous powder for laser cladding and a preparation method thereof, and comprises Zr-Cu-Al-Ti-Sn amorphous blocks and B powder; the atomic ratio of Cu in the Zr-Cu-Al-Ti-Sn amorphous blocks is 10-20, the atomic ratio of Al is 7, the atomic ratio of Ti is 10-20, wherein the atomic ratio of Ti is equal to the atomic ratio of Cu, the atomic ratio of Sn is 1-5, Zr is the balance, and the total value of the atomic ratio is 100; the Zr-Cu-Al-Ti-Sn amorphous blocks are subjected to smelting and atomization powdering to form the amorphous powder, and then the B powder and the amorphous powder are mixed to obtain the amorphous powder for laser cladding. The application utilizes the characteristics of the amorphous material, such as no magnetism, high hardness and wear resistance, to manufacture an amorphous material suitable for a non-magnetic working condition, and is specially used for laser cladding repair operations of non-magnetic workpieces.

Description

Technical Field

[0001] This invention belongs to the field of laser cladding technology, specifically to an amorphous powder for laser cladding and its preparation method. Background Technology

[0002] Laser cladding technology refers to a technique in which a coating material is irradiated with a laser to form a metallurgical bond between the coating material and the substrate surface. After being irradiated with high energy, the coating material melts and solidifies rapidly to form a surface coating with extremely low dilution, which can significantly improve the wear resistance, corrosion resistance, heat resistance, and oxidation resistance of the substrate material surface.

[0003] The final performance of a coating depends primarily on the coating material and the irradiation process. Compared to the irradiation process, the choice of coating material has a greater impact on the final coating performance. Currently available coating materials mainly include Fe-based, Co-based, and Ni-based materials. Fe-based self-alloying is suitable for parts requiring localized wear resistance and prone to deformation. The substrate is often cast iron or low-carbon steel. Its biggest advantages are low cost and good wear resistance, but it has a high melting point, poor alloy self-fluidization, poor oxidation resistance, poor fluidity, and a high number of pores and inclusions in the molten layer. Co-based alloy powder is mainly used on steel-based alloy substrates and is suitable for parts requiring wear resistance, corrosion resistance, and resistance to thermal fatigue. Ni-based alloy powder is the most widely used in laser cladding technology due to its good wettability, corrosion resistance, high-temperature self-lubricating properties, and moderate price. It is suitable for components requiring localized wear resistance, heat corrosion resistance, and resistance to thermal fatigue.

[0004] While these cladding materials excel in certain aspects, they are all magnetic, making them unsuitable for applications requiring a non-magnetic environment. Therefore, developing wear-resistant materials for non-magnetic environments is crucial for laser cladding. Summary of the Invention

[0005] To address the problems existing in the prior art, the present invention provides an amorphous powder for laser cladding and a method for preparing the same, thereby solving the aforementioned problems.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] An amorphous powder for laser cladding comprises Zr-Cu-Al-Ti-Sn amorphous bulk and B powder;

[0008] In the Zr-Cu-Al-Ti-Sn amorphous bulk, the atomic ratio of Cu is 10-20, the atomic ratio of Al is 7, the atomic ratio of Ti is 10-20, the atomic ratio of Ti is equal to that of Cu, the atomic ratio of Sn is 1-5, Zr is the balance, and the total atomic ratio is 100.

[0009] Zr-Cu-Al-Ti-Sn amorphous bulk material is smelted and atomized to form amorphous powder. Then, B powder and amorphous powder are mixed to obtain amorphous powder for laser cladding.

[0010] Preferably, the purity of elemental Zr, Cu, Al, Ti, and Sn in the Zr-Cu-Al-Ti-Sn amorphous bulk is higher than 99.99%.

[0011] Preferably, the particle size range of the B powder is 50-100 μm.

[0012] A method for preparing amorphous powder for laser cladding includes the following steps:

[0013] Step 1: Take Zr, Cu, Al, Ti, and Sn and melt them to form Zr-Cu-Al-Ti-Sn amorphous bulk material;

[0014] In the Zr-Cu-Al-Ti-Sn amorphous bulk, the atomic ratio of Cu is 10-20, the atomic ratio of Al is 7, and the atomic ratio of Ti is 10-20. The atomic ratio of Ti is equal to that of Cu, the atomic ratio of Sn is less than 5, and Zr is the balance. The total atomic ratio is 100.

[0015] Step 2: Atomize the Zr-Cu-Al-Ti-Sn amorphous bulk material to form amorphous powder;

[0016] Step 3: Mix the amorphous powder with no more than 200 ppm of B powder to obtain the amorphous powder for laser cladding.

[0017] Preferably, in step 1, Zr, Cu, Al, Ti, and Sn are first smelted in a vacuum arc melting furnace.

[0018] After the environment is evacuated to a vacuum, an electric arc gun is used for melting. Once the block is completely melted, it is stirred. After stirring and cooling, the block is flipped over and melted again. After melting at least 5 times, an amorphous block is obtained.

[0019] Preferably, in step 2, the amorphous bulk material from step 1 is heated to melt and then pressed into powder using nitrogen gas to form amorphous powder.

[0020] Furthermore, in step 2, the purity of N2 used for atomization is higher than 99.999%, and the gas pressure is above 50 MPa.

[0021] Preferably, in step 2, the particle size range of the amorphous powder is 20-100 μm.

[0022] Preferably, the vacuum is maintained at 10°C during the melting in step 1 and the atomization powdering in step 2.-4 Pa or above.

[0023] Preferably, in step 3, the amorphous powder and B powder are ball-milled and mixed at a ball-to-powder ratio of 5:1, a rotation speed of 150 rpm, and a time of half an hour.

[0024] Compared with the prior art, the present invention has the following beneficial technical effects:

[0025] This invention provides an amorphous powder for laser cladding. Amorphous materials, due to their unique structure of long-range disorder and short-range order, possess unique properties not found in crystalline alloys. For example, they exhibit isotropic characteristics in physical, chemical, and mechanical aspects, and also display relatively excellent hardness and sufficiently superior wear resistance. Furthermore, most non-ferrous amorphous materials are non-magnetic. This invention utilizes the non-magnetic, high-hardness, and wear-resistant properties of amorphous materials to create an amorphous material suitable for non-magnetic working conditions, specifically designed for laser cladding repair of non-magnetic workpieces. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the laser cladding layer;

[0027] Figure 2 This is a schematic diagram of the coating after laser cladding. Detailed Implementation

[0028] The present invention will be further described in detail below with reference to specific embodiments. These descriptions are for explanation purposes only and are not intended to limit the scope of the invention.

[0029] A raw material specifically designed for laser cladding repair of non-magnetic tools. The main components of this raw material are Zr-Cu-Al-Ti-Sn-B. The preparation method is as follows: First, an amorphous bulk Zr-Cu-Al-Ti-Sn is prepared, then atomized into powder. Next, B is mixed with the amorphous powder to obtain the laser cladding powder raw material. The composition of the amorphous bulk is: Cu atomic ratio of 10-20, Al atomic ratio of 7, Ti atomic ratio of 10-20 (the Ti atomic ratio should be consistent with Cu), Sn atomic ratio ranging from 1-5, and Zr as the balance. The preparation process of the amorphous powder is as follows: First, each element is weighed and proportioned according to its atomic ratio. After proportioning, it is melted in a vacuum melting furnace, using an electric arc furnace or a vacuum induction furnace, at 10... -4The bulk material was melted five times under vacuum until homogeneous, and then cooled in a water-cooled copper crucible to obtain a Zr-Cu-Al-Ti-Sn amorphous bulk. The Zr-Cu-Al-Ti-Sn amorphous material was then melted in a magnesia crucible and atomized into powder under N2 atmosphere. Specific process parameters are as follows: the amorphous bulk was induction heated using high-purity N2 with a purity of 99.999% or higher and a pressure greater than 50 MPa. The molten amorphous bulk was then sprayed into powder. The obtained powder was screened, and powder with a particle size of 20-100 μm was selected. 200 ppm of boron powder with a particle size of 50-100 μm was added to this powder. The amorphous powder and boron powder were mixed by low-speed ball milling until homogeneous, resulting in the non-magnetic amorphous raw material for laser cladding developed in this patent.

[0030] (1) The final powder must be a mixture of amorphous powder and B powder using low-energy ball milling. (2) The preparation of amorphous powder requires the use of amorphous bulk material for atomization powdering. The raw material for amorphous bulk material must be limited to the above-mentioned components to ensure the success of the three processes: smelting, atomization powdering, and laser cladding. (3) After obtaining the amorphous powder, it is ball-milled with B powder using low-energy ball milling. (4) The final mixed powder is non-magnetic. (5) Laser cladding equipment is used for laser cladding to obtain the desired powder. Figure 1 The structure contains amorphous structure (substrate), dendrites, and Ti2Cu (white structure).

[0031] Raw materials must be prepared strictly according to the ingredient ratios, and their purity must be higher than 99.99%. Vacuum must be maintained at 10°C during smelting and atomization powdering. -4 In addition, the purity of N2 used for atomized powder production must be higher than 99.999%, and the gas pressure must be higher than 50 MPa.

[0032] The prepared amorphous powder needs to be screened for particle size, with the particle size range as required above. Then, it is mixed with B powder (with specific particle size requirements) through low-energy ball milling. The content of B powder must be less than 200 ppm. During ball milling, the ball-to-powder ratio should be less than 10:1 (i.e., powder mass greater than 10%), and the rotation speed should be less than 200 rpm. The purpose is to allow the B powder to adhere to the amorphous powder, possessing a certain mechanical bonding force (ordinary vibration cannot detach it), while ensuring that the amorphous powder is not crystallized.

[0033] Example 1

[0034] (1) Melting amorphous bulk materials

[0035] Zr-Cu-Al-Ti-Sn elements with a purity exceeding 99.99% were used. The atomic ratio of Zr, Cu, Al, Ti, and Sn was 70:10.5:7:10.5:2. After converting to a mass ratio, the components were weighed and melted in a vacuum arc melting furnace. The vacuum was increased to 10... -5After the initial melting process (pa), the block is melted using an electric arc gun. Once completely melted, it is then electromagnetically stirred for 5 minutes. After cooling, the block is flipped over and melted again. This process is repeated 5 times to obtain the amorphous block.

[0036] (2) Atomization powder production

[0037] The amorphous bulk material obtained from smelting is atomized into powder. First, the vacuum is evacuated to 10... -5 After pressing at 80 MPa, the material was induction heated until the bulk material melted. Then, six nitrogen cylinders with a purity of 99.999% were used for high-pressure powder production, with a total pressure of 80 MPa. The resulting powder was then screened for particle size, ranging from 20 to 100 μm.

[0038] (3) Powder mixing

[0039] The amorphous powder was ball-milled with 200 ppm of 100 μm B powder at a ball-to-powder ratio of 5:1, at a speed of 150 rpm, for half an hour.

[0040] (4) Laser cladding

[0041] This powder can be used to perform laser cladding on products that need repair. Figure 2 This is a schematic diagram of Example 1.

[0042] Example 2

[0043] (1) Melting amorphous bulk materials

[0044] Zr-Cu-Al-Ti-Sn elements with a purity exceeding 99.99% were used. The atomic ratio of Zr, Cu, Al, Ti, and Sn was 72:10:7:10:1. After converting to a mass ratio, the components were weighed and smelted in a vacuum arc melting furnace. The vacuum was increased to 10... -5 After the initial melting process (pa), the block is melted using an electric arc gun. Once completely melted, it is then electromagnetically stirred for 5 minutes. After cooling, the block is flipped over and melted again. This process is repeated 5 times to obtain the amorphous block.

[0045] (2) Atomization powder production

[0046] The amorphous bulk material obtained from smelting is atomized into powder. First, the vacuum is evacuated to 10... -4 After pressing at 80 MPa, the material was induction heated until the bulk material melted. Then, six nitrogen cylinders with a purity of 99.999% were used for high-pressure powder production, with a total pressure of 80 MPa. The resulting powder was then screened for particle size, ranging from 20 to 100 μm.

[0047] (3) Powder mixing

[0048] The amorphous powder was ball-milled with 100 ppm of 100 μm B powder at a ball-to-powder ratio of 5:1, at a speed of 150 rpm, for half an hour.

[0049] (4) Laser cladding

[0050] This powder can be used to perform laser cladding on products that need repair.

[0051] Example 3

[0052] (1) Melting amorphous bulk materials

[0053] Zr-Cu-Al-Ti-Sn elements with a purity exceeding 99.99% were used. The atomic ratio of Zr, Cu, Al, Ti, and Sn was 50:20:7:20:3. After converting to a mass ratio, the components were weighed and smelted in a vacuum arc melting furnace. The vacuum was increased to 10... -5 After the initial melting process (pa), the block is melted using an electric arc gun. Once completely melted, it is then electromagnetically stirred for 5 minutes. After cooling, the block is flipped over and melted again. This process is repeated 5 times to obtain the amorphous block.

[0054] (2) Atomization powder production

[0055] The amorphous bulk material obtained from smelting is atomized into powder. First, the vacuum is evacuated to 10... -4 After pressing at 80 MPa, the material was induction heated until the bulk material melted. Then, six nitrogen cylinders with a purity of 99.999% were used for high-pressure powder production, with a total pressure of 80 MPa. The resulting powder was then screened for particle size, ranging from 20 to 100 μm.

[0056] (3) Powder mixing

[0057] Amorphous powder was mixed with 150 ppm of 20 μm B powder by ball milling at a ball-to-powder ratio of 5:1, at a speed of 150 rpm, for half an hour.

[0058] (4) Laser cladding

[0059] This powder can be used to perform laser cladding on products that need repair.

[0060] Example 4

[0061] (1) Melting amorphous bulk materials

[0062] Zr-Cu-Al-Ti-Sn elements with a purity exceeding 99.99% were used. The atomic ratio of Zr, Cu, Al, Ti, and Sn was 61:15:7:15:2. After converting to a mass ratio, the components were weighed and smelted in a vacuum arc melting furnace. The vacuum was increased to 10... -5 After the initial melting process (pa), the block is melted using an electric arc gun. Once completely melted, it is then electromagnetically stirred for 5 minutes. After cooling, the block is flipped over and melted again. This process is repeated 5 times to obtain the amorphous block.

[0063] (2) Atomization powder production

[0064] The amorphous bulk material obtained from smelting is atomized into powder. First, the vacuum is evacuated to 10... -4 After pressing at 80 MPa, the material was induction heated until the bulk material melted. Then, six nitrogen cylinders with a purity of 99.999% were used for high-pressure powder production, with a total pressure of 80 MPa. The resulting powder was then screened for particle size, ranging from 20 to 100 μm.

[0065] (3) Powder mixing

[0066] The amorphous powder was ball-milled with 200 ppm of 100 μm B powder at a ball-to-powder ratio of 5:1, at a speed of 150 rpm, for half an hour.

[0067] (4) Laser cladding

[0068] This powder can be used to perform laser cladding on products that need repair.

[0069] Example 5

[0070] (1) Melting amorphous bulk materials

[0071] Zr-Cu-Al-Ti-Sn elements with a purity exceeding 99.99% were used. The atomic ratio of Zr, Cu, Al, Ti, and Sn was 62:13:7:13:5. After converting to a mass ratio, the components were weighed and smelted in a vacuum arc melting furnace. The vacuum was increased to 10... -5 After the initial melting process (pa), the block is melted using an electric arc gun. Once completely melted, it is then electromagnetically stirred for 5 minutes. After cooling, the block is flipped over and melted again. This process is repeated 5 times to obtain the amorphous block.

[0072] (2) Atomization powder production

[0073] The amorphous bulk material obtained from smelting is atomized into powder. First, the vacuum is evacuated to 10... -4 After pressing at 80 MPa, the material was induction heated until the bulk material melted. Then, six nitrogen cylinders with a purity of 99.999% were used for high-pressure powder production, with a total pressure of 80 MPa. The resulting powder was then screened for particle size, ranging from 20 to 100 μm.

[0074] (3) Powder mixing

[0075] The amorphous powder was ball-milled with 200 ppm of 50 μm B powder at a ball-to-powder ratio of 5:1, at a speed of 150 rpm, for half an hour.

[0076] (4) Laser cladding

[0077] This powder can be used to perform laser cladding on products that need repair.

Claims

1. A method for preparing amorphous powder for laser cladding, characterized in that, Includes the following steps, Step 1: Take Zr, Cu, Al, Ti, and Sn elements with a purity all higher than 99.99% and melt them in a vacuum arc melting furnace to form Zr-Cu-Al-Ti-Sn amorphous blocks. Turn the blocks over and melt them again. Repeat the melting process at least five times, maintaining a vacuum of 10°C during melting. -4 above pa; In the Zr-Cu-Al-Ti-Sn amorphous bulk, the atomic ratio of Cu is 10-20, the atomic ratio of Al is 7, and the atomic ratio of Ti is 10-20. The atomic ratio of Ti is equal to that of Cu, the atomic ratio of Sn is less than 5, and Zr is the balance. The total atomic ratio is 100. Step 2: The Zr-Cu-Al-Ti-Sn amorphous bulk is heated to melt and then subjected to high-pressure grinding with nitrogen to form amorphous powder. The N2 purity used in the atomization grinding process is higher than 99.999%, the pressure is above 50 MPa, the particle size of the amorphous powder ranges from 20 to 100 μm, and the vacuum during grinding is maintained at 10... -4 above pa; Step 3: Mix B powder with a particle size range of 50-100μm and a content of no more than 200ppm with amorphous powder using low-energy ball milling. The ball-to-powder ratio is 5:1, the rotation speed is 150rpm, and the time is half an hour. This allows the B powder to adhere to the amorphous powder, providing a certain mechanical bonding force, while ensuring that the amorphous powder does not crystallize, thus obtaining amorphous powder for laser cladding.

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