3D printing preparation method of metallic bond diamond grinding wheel

Abstract

The invention discloses a 3D printing preparation method of a metallic bond diamond grinding wheel, an aluminum substrate and a metallic bond diamond grinding wheel block are directly printed and formed in a 3D printing mode, and the working procedures of machining forming of the substrate, cold pressing and sintering forming of the diamond grinding wheel block, bonding of the diamond grinding wheel block and the substrate and the like in the grinding wheel manufacturing process are reduced. And the machining efficiency is improved, the equipment requirement in the grinding wheel preparation process is reduced, the use of an adhesive is avoided, dust in the preparation process is reduced, and the environmental protection property in the grinding wheel preparation process is improved.

Description

Technical Field

[0001] This invention belongs to the field of 3D printing technology, and specifically relates to a 3D printing preparation method for a metal-bonded diamond grinding wheel. Background Technology

[0002] Diamond possesses excellent properties such as high hardness, high wear resistance, good thermal conductivity, and low coefficient of friction, making diamond tools widely applicable in high-speed, high-precision cutting and grinding, as well as the efficient machining of hard and brittle materials. Diamond grinding wheels constitute a significant proportion of diamond tools. Based on the type of bond, diamond grinding wheels are mainly classified into metal-bonded diamond wheels, resin-bonded diamond wheels, and ceramic-bonded diamond wheels. Metal-bonded diamond wheels offer advantages such as high strength and good wear resistance. Resin-bonded diamond wheels have high elasticity and good self-sharpening properties, making them suitable for finishing and ultra-finishing. However, the addition of resin binders makes it difficult to achieve ultra-fine particle sizes in resin abrasives, resulting in limited application in ultra-precision machining. Ceramic-bonded diamond wheels, with their high strength and high sharpness, have numerous applications in the ultra-precision machining of hard and brittle materials such as tungsten carbide, sapphire, and silicon carbide.

[0003] The traditional manufacturing process of metal-bonded diamond grinding wheels mainly includes: mixing, hot pressing in a mold, bonding, and dressing. Diamond carbonizes at high temperatures, therefore the sintering temperature of the grinding wheel often needs to be controlled below 700℃. Since this temperature does not reach the melting point of metals, the high-temperature sintering of diamond grinding wheels is considered solid-state sintering. Grinding wheel blocks for different applications have different shapes, including complex-shaped grinding wheel blocks (such as...). Figure 1 Traditional molding methods are difficult because the temperature does not reach the melting temperature of the metal powder, resulting in poor flowability of the solid powder. This often leads to material shortages during the pressing of complex-shaped grinding wheel blocks, affecting grinding wheel production. The advantage of 3D printing lies precisely in its ability to complete additive manufacturing of complex shapes with minimal material removal during processing.

[0004] The invention disclosed in CN115138859A is an integrally formed diamond grinding wheel and its preparation method. The key technical points of the solution include that the working layer of the diamond grinding wheel is a metal-based diamond composite material, the matrix is ​​steel, and 3D printing is used. Through a dual model array of matrix and working layer, a laser selective melting device is used to scan the two models in the same layer respectively, and remelting is performed at the interface of the heterogeneous materials to achieve an integrally formed heterogeneous diamond grinding wheel. Although it discloses a dual model array of matrix and working layer and uses laser selective melting technology to carry out a melting process at the interface between the matrix and working layer, it still needs to use a remelting process at the interface to improve the interfacial bonding strength between the heterogeneous materials. Therefore, it cannot be directly applied to the preparation of aluminum-based diamond grinding wheels.

[0005] Therefore, it is still necessary to develop a method for preparing metal-bonded diamond grinding wheels using 3D printing technology. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of the prior art by providing a 3D printing method for preparing metal-bonded diamond grinding wheels, which additively forms metal-bonded diamond grinding wheels on an aluminum substrate, thereby reducing the overall processing steps of the grinding wheel.

[0007] To solve the above technical problems, the technical solution adopted by the present invention is as follows: A method for 3D printing a metal-bonded diamond grinding wheel includes the following steps: (1) Preparation of aluminum matrix metal powder (2) Preparation of metal binder powder The mass fraction ratio of each component is as follows: copper 25-35%, tin 20-30%, cobalt 10-20%, tungsten 5-10%, graphite 1.5-3.5%, and organic pore-forming agent 2-5%. (3) Mix the metal binder with diamond micro powder and mix for 5-10 minutes using an acoustic resonance mixer; (4) Set the printing device parameters Set the laser power and laser wavelength, the powder layer thickness is 30-100μm, the protective atmosphere is Ar / N2, and the size of the molded part is not less than 100*100*50mm; (5) Add aluminum powder to the first material box of the 3D printing equipment, and add binder-diamond powder to the second material box of the 3D printing equipment; (6) The first material box is filled with powder and the substrate is printed; (7) After the substrate is printed, multiple positioning grooves are left at intervals along the circumference on the substrate surface. Clean the remaining metal powder on the worktable and the aluminum powder in the surface structure of the aluminum substrate. (8) Spread powder in the second material box, adjust the laser power and scanning time, introduce a protective atmosphere, and control the temperature of the printing area to not exceed 700℃ to complete the printing of the metal bond diamond grinding wheel block; (9) After printing, the substrate is finished, the diamond grinding wheel block is ground and sharpened, and the dynamic balance of the grinding wheel is completed on the corresponding machine tool.

[0008] In step (2), the organic pore-forming agent is alumina hollow ceramic microspheres with a diameter of 1-2.5 μm.

[0009] In step (2), the particle size of each metal powder is within w40.

[0010] In step (3), the diamond powder used has a particle size of w28-w20.

[0011] In step (4), the laser power is set to 500W and the laser wavelength is 1060nm.

[0012] In step (8), N2 is introduced as a protective atmosphere.

[0013] The beneficial effects of this invention are: (1) This invention discloses a 3D printing preparation method for metal-bonded diamond grinding wheels. The aluminum substrate and the metal-bonded diamond grinding wheel block are directly printed by 3D printing, which reduces the machining of the substrate, cold pressing and sintering of the diamond grinding wheel block, and bonding of the diamond grinding wheel block to the substrate in the grinding wheel making process. This improves the processing efficiency, reduces the equipment requirements in the grinding wheel preparation process, avoids the use of adhesives, reduces dust in the preparation process, and improves the environmental friendliness of the grinding wheel preparation process.

[0014] (2) The metal-bonded diamond grinding wheel block is directly formed by additive manufacturing of the matrix and the diamond grinding wheel block using 3D printing. It can realize the preparation of grinding wheel blocks with complex structures, and has high efficiency, small amount of material removal during final grinding, and overall environmental friendliness is higher than that of traditional preparation methods. Traditional matrix production often uses the subtractive processing of a whole aluminum plate, which has a high material removal rate, long processing cycle, and requires a large number of equipment. Using 3D printing to directly form the matrix can reduce the consumption of raw materials and shorten the matrix preparation cycle.

[0015] (3) The use of instantaneous high energy laser replaces the powder cold pressing and hot pressing sintering process of grinding wheel blocks, which reduces equipment investment, optimizes the on-site working environment, shortens the grinding wheel preparation process, reduces the bonding process between the matrix and the diamond grinding wheel block, reduces the use of harmful chemical reagents, and improves the safety of the working environment.

[0016] (4) The use of dual powder boxes enables the printing of the entire grinding wheel in one loading, avoiding the need to wait for the substrate to be processed before the grinding wheel powder is added and the grinding wheel printing begins. This allows the substrate and grinding wheel to be bonded together at high temperature, replacing the traditional glue bonding.

[0017] (5) The method of layering the matrix and grinding wheel block on a 3D printing machine avoids the loading and unloading process of raw materials such as the matrix, which can effectively improve the processing accuracy and efficiency. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the preparation process of the present invention; Figure 2 This is a front view of a metal-bonded diamond grinding wheel block; Figure 3 This is a top view of a metal-bonded diamond grinding wheel block; Figure 4 This is a schematic diagram of the aluminum matrix structure; Figure 5 This is a cross-sectional view of the aluminum substrate; Figure 6 This is a schematic diagram showing the bonding of the diamond grinding wheel and the aluminum substrate using a metal-bonded agent. Figure 7 yes Figure 6 A sectional view; Figure 8 This is a diagram illustrating the printing process. Detailed Implementation

[0019] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to represent selected embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] This invention provides a 3D printing method for preparing a metal-bonded diamond grinding wheel, such as... Figures 1 to 8 As shown.

[0022] A method for 3D printing a metal-bonded diamond grinding wheel includes the following steps: (1) Preparation of aluminum matrix metal powder (2) Preparation of metal binder powder The mass fraction of each component is as follows: copper 25-35%, tin 20-30%, cobalt 10-20%, tungsten 5-10%, graphite 1.5-3.5%, and organic pore-forming agent 2-5%. In this embodiment, the organic pore-forming agent is alumina hollow ceramic microspheres with a diameter of 1-2.5 μm, and the particle size of each metal powder is within w40.

[0023] (3) The metal binder and diamond powder are mixed and mixed for 5-10 minutes using an acoustic resonance mixer; the diamond powder can be micro powder with a particle size of w28-w20.

[0024] (4) Set the printing device parameters Set the laser power and laser wavelength, the powder layer thickness is 30-100μm, the protective atmosphere is Ar / N2, and the size of the molded part is not less than 100*100*50mm; (5) Add aluminum powder 3 to the first material box 5 of the 3D printing equipment, and add binder-diamond powder 4 to the second material box 6 of the 3D printing equipment; (6) The first material box is filled with powder and the substrate 1 is printed; (7) After the substrate 1 is printed, multiple positioning grooves are left at intervals along the circumference on the substrate surface. Clean the remaining metal powder on the worktable and the aluminum powder in the surface structure of the aluminum substrate. (8) Spread powder in the second material box, adjust the laser power and scanning time, introduce a protective atmosphere, preferably N2 as the protective atmosphere, and control the temperature of the printing area to not exceed 700℃ to complete the printing of the metal bond diamond grinding wheel block 2. (9) After printing, the substrate is finished, the diamond grinding wheel block is ground and sharpened, and the dynamic balance of the grinding wheel is completed on the corresponding machine tool.

[0025] In step (4), the laser power is set to 500W and the laser wavelength is 1060nm.

[0026] The following description, in conjunction with specific embodiments, provides further details: The main components and mass fraction ratio of the metal binder are: copper 25-35%, tin 20-30%, cobalt 10-20%, tungsten 5-10%, graphite 1.5-3.5%, and organic pore-forming agent about 2%. The particle size of each metal powder is within w40, and the organic pore-forming agent is alumina hollow ceramic microspheres with a diameter in the range of 1-2.5μm.

[0027] Subsequently, a certain mass of powders of different components is coarsely mixed with diamond micro powder, and the diamond micro powder can be micro powder with a particle size of w28-w20. After mixing, the mixture is placed in an acoustic resonance mixer and mixed at a frequency of 60Hz and an acceleration of 20G for 5 minutes; or a planetary ball mill is used at 80rpm, and the mixture is ball-milled alternately in both directions for 1 hour, and repeated about three times.

[0028] After mixing, take a sample and observe the mixing of each component using an optical microscope or scanning electron microscope. Count the number of particles in each component through the eyepiece. If the number deviation between different components is within 10%, it can be determined that the mixing uniformity is good. After obtaining a powder with good uniformity, the process ends.

[0029] Place a sufficient amount of aluminum metal powder into the first material box 5 of the 3D printing equipment, and place the uniformly mixed metal binder-diamond mixed powder into the second material box 6 of the equipment. Import the grinding wheel model into the 3D printer and complete the slicing, powder spreading, and printing parameter settings.

[0030] The printing equipment used is BLT-S310, with the laser power set to 500W, the laser wavelength to 1060nm, the powder layer thickness to 30μm or 40μm, the protective atmosphere to be N2, and the scanning speed to 1000-1500mm / s.

[0031] After the aluminum substrate is printed, the residual aluminum powder inside the pits on the substrate needs to be removed. Then, the metal binder-diamond mixed powder is laid. During the printing of the metal binder diamond grinding wheel block, the laser power and scanning speed need to be adjusted to keep the temperature of the printing area below 750℃. N2 is also required as a protective atmosphere to complete the printing of the grinding wheel block.

[0032] After the overall printing is completed, the substrate is finished by machining, the diamond grinding wheel blocks are regrinded and sharpened, and the dynamic balance of the grinding wheel is completed.

[0033] The 3D printing method for preparing metal-bonded diamond grinding wheels disclosed in this invention directly prints an aluminum substrate and a metal-bonded diamond grinding wheel block using 3D printing. This reduces the steps involved in grinding wheel manufacturing, such as machining the substrate, cold pressing and sintering the diamond grinding wheel block, and bonding the diamond grinding wheel block to the substrate. This improves processing efficiency, reduces equipment requirements in the grinding wheel manufacturing process, avoids the use of adhesives, reduces dust during the manufacturing process, and enhances the environmental friendliness of the grinding wheel manufacturing process.

[0034] The endpoints and any values ​​of the ranges disclosed herein are not limited to the exact ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0035] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this invention is defined by the appended claims and their equivalents.

[0036] In the description of this invention, it should be understood that the terms "front", "rear", "left", "right", "center", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only used to facilitate the description of this invention and to simplify the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

Claims

1. A method for 3D printing a metal-bonded diamond grinding wheel, characterized in that, Includes the following steps: (1) Preparation of aluminum matrix metal powder (2) Preparation of metal binder powder The mass fraction ratio of each component is as follows: copper 25-35%, tin 20-30%, cobalt 10-20%, tungsten 5-10%, graphite 1.5-3.5%, and organic pore-forming agent 2-5%. The metal binder and diamond micro powder are mixed and then mixed for 5-10 minutes using an acoustic resonance mixer. Set printing device parameters Set the laser power and laser wavelength, the powder layer thickness is 30-100μm, the protective atmosphere is Ar / N2, and the size of the molded part is not less than 100*100*50mm; (5) Add aluminum powder to the first material box of the 3D printing equipment, and add binder-diamond powder to the second material box of the 3D printing equipment; (6) The first material box is filled with powder and the substrate is printed; (7) After the substrate is printed, multiple positioning grooves are left at intervals along the circumference on the substrate surface. Clean the remaining metal powder on the worktable and the aluminum powder in the surface structure of the aluminum substrate. (8) Spread powder in the second material box, adjust the laser power and scanning time, introduce a protective atmosphere, and control the temperature of the printing area to not exceed 700℃ to complete the printing of the metal bond diamond grinding wheel block; (9) After printing, the substrate is finished, the diamond grinding wheel block is ground and sharpened, and the dynamic balance of the grinding wheel is completed on the corresponding machine tool.

2. The 3D printing preparation method of a metal-bonded diamond grinding wheel according to claim 1, characterized in that: In step (2), the organic pore-forming agent is alumina hollow ceramic microspheres with a diameter of 1-2.5 μm.

3. The 3D printing preparation method of a metal-bonded diamond grinding wheel according to claim 1, characterized in that: In step (2), the particle size of each metal powder is within w40.

4. The 3D printing preparation method of a metal-bonded diamond grinding wheel according to claim 1, characterized in that: In step (3), the diamond powder used has a particle size of w28-w20.

5. The 3D printing preparation method of a metal-bonded diamond grinding wheel according to claim 1, characterized in that: In step (4), the laser power is set to 500W and the laser wavelength is 1060nm.

6. The 3D printing preparation method of a metal-bonded diamond grinding wheel according to claim 1, characterized in that: In step (8), N2 is introduced as a protective atmosphere.

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