A polishing process for cemented carbide dies

Abstract

This invention discloses a polishing process for cemented carbide molds, relating to the field of cemented carbide mold processing technology. The process involves first degreasing and dehydrating the cemented carbide mold, followed by rough polishing, and finally placing the mold in a sealed space for sandblasting polishing. The sandblasting polishing process is adjusted according to the roughness and / or hardness of the cemented carbide mold. This invention employs a novel mold polishing process, resulting in a smoother and more consistent mold surface. It also solves the problem of traditional methods being unable to polish deep, small grooves, while reducing mold rework and improving the efficiency of fitter operations. The overall surface finish of the finished mold is improved, and its service life is extended. Surface defects during CNC cutting are significantly reduced, surface quality is significantly improved, and cutting efficiency is significantly increased.

Description

Technical Field

[0001] This invention relates to the field of cemented carbide mold processing technology, and more specifically to a polishing process for cemented carbide molds. Background Technology

[0002] Polishing refers to a processing method that uses mechanical, chemical, or electrochemical actions to reduce the surface roughness of a workpiece, thereby obtaining a bright and smooth surface. It involves using polishing tools and abrasive particles or other polishing media to refine the surface of a workpiece. Existing polishing processes suffer from high mold rework rates, heavy manual labor in the fitting process, product accumulation, poor mold surface finish, short mold lifespan, numerous surface defects in CNC inserts, low pressing yield, frequent material sticking during pressing, and frequent punch rubbing. Existing molds also present challenges in machining complex grooved electrodes, polishing the molds, and cleaning them during pressing, all of which negatively impact insert surface defects and pressing efficiency.

[0003] Due to the unique material properties of cemented carbide molds, different processing techniques often result in varying surface finishes, leading to inconsistent polishing processes. Electrical discharge machining (EDM) produces a relatively rough surface, and simple surface polishing often fails to achieve the required roughness, while also shortening the mold's lifespan. This necessitates mold makers possessing extensive polishing experience and skills to precisely manipulate the mold and ensure the final precision and surface quality. Because of the high hardness and wear resistance of cemented carbide molds, harder abrasives and stronger polishing fluids are required during polishing, increasing the complexity of the polishing tools and process.

[0004] After the mold dimensions pass inspection, it is first degreased and dehydrated, then polished with diamond polishing compound. Initially, a coarser polishing compound, W28, is used for rough polishing to remove the rough texture. Then, a finer polishing compound, W20, is used, followed by W14, and then W10 for fine polishing. Finally, a finer polishing compound, W5, is used for mirror polishing, and then W2.5, the finest polishing compound, until a mirror finish is achieved.

[0005] The polishing process is extremely time-consuming, requiring 4-6 hours, and it is difficult to achieve consistency after polishing complex grooves, making it even more time-consuming.

[0006] Only when a mold has a consistent mirror finish can it have a longer service life. Summary of the Invention

[0007] The purpose of this invention is to at least solve one of the technical problems existing in the prior art and to provide a polishing process for cemented carbide molds.

[0008] The technical solution of the present invention is as follows:

[0009] A polishing process for a cemented carbide mold involves first degreasing and dewatering the cemented carbide mold, then rough polishing, and finally placing the cemented carbide mold in a sealed space for sandblasting and polishing.

[0010] Adjust the sandblasting and polishing process according to the roughness and / or hardness of the cemented carbide mold.

[0011] As a preferred embodiment of the present invention, the sandblasting and polishing process is adjusted according to the roughness and hardness of the cemented carbide mold as follows:

[0012] When the surface roughness of the cemented carbide mold is Ra0.3-5 and / or HRA86.5-88.0, use 1400-1600 mesh abrasive, pressure 0.5-0.7 MPa, and processing time 20-40 min;

[0013] When the surface roughness of the cemented carbide mold is Ra 0.1-0.3 and / or HRA 85.8-86.8, use 1800-2200 mesh abrasive, pressure 0.4-0.6 MPa, and processing time 10-30 min;

[0014] When the surface roughness of the cemented carbide mold is Ra 0.05-0.15 and / or HRA 82.5-84.5, use 2800-3200 mesh abrasive, pressure 0.3-0.5 MPa, and processing time 10-20 min.

[0015] As a preferred embodiment of the present invention, the sandblasting and polishing process is adjusted according to the roughness and hardness of the cemented carbide mold as follows:

[0016] When the surface roughness of the cemented carbide mold is Ra0.4 and / or HRA86.5-88.0, use 1500-mesh abrasive, pressure 0.6 MPa, and processing time 30 min;

[0017] When the surface roughness of the cemented carbide mold is Ra0.2 and / or HRA85.8-86.8, use 2000-mesh abrasive, pressure 0.5 MPa, and processing time 20 min;

[0018] When the surface roughness of the cemented carbide mold is Ra0.1 and / or HRA82.5-84.5, use 3000-mesh abrasive, pressure 0.4 MPa, and processing time 15 min.

[0019] In a preferred embodiment of the present invention, the abrasive is at least one selected from diamond micro powder, nano-silica, and boron carbide particles. It also includes elastic polymer particles.

[0020] As a preferred embodiment of the present invention, the elastic polymer particles include butylene terephthalate and / or polystyrene.

[0021] As a preferred embodiment of the present invention, the roughing and polishing is specifically performed using polishing paste W20-40.

[0022] As a preferred embodiment of the present invention, the polishing paste specifically comprises the following raw materials in parts by weight: 100-300 parts stearic acid, 200-400 parts paraffin wax, 50-80 parts trimethylolpropane trimethacrylate, 100-120 parts polyethylene glycol and 100-300 parts anhydrous ethanol.

[0023] As a preferred embodiment of the present invention, the degreasing specifically involves cleaning with a cleaning agent;

[0024] The dehydration process specifically involves drying with inert gas.

[0025] The beneficial effects of this invention are: the invention adopts a new mold polishing process, which makes the mold surface smoother and more consistent, and solves the problem that deep and small grooves cannot be polished in the traditional way. At the same time, it reduces the amount of mold rework and improves the efficiency of the fitter's operation. The overall smoothness of the finished mold is improved and its service life is extended. The surface defects of the CNC cutting tool are significantly reduced, the surface quality is significantly improved, and the pressing efficiency is significantly improved. Detailed Implementation

[0026] The embodiments of the present invention are described in detail below. These embodiments are exemplary and are only used to explain the present invention, and should not be construed as limiting the invention. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in the art or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all commercially available conventional products.

[0027] Example 1

[0028] A polishing process for a cemented carbide mold involves first degreasing and dewatering the cemented carbide mold, then rough polishing, and finally placing the cemented carbide mold in a sealed space for sandblasting and polishing.

[0029] Adjust the sandblasting and polishing process according to the roughness and / or hardness of the cemented carbide mold.

[0030] The surface roughness of the cemented carbide mold is Ra0.4 (HRA86.5-88.0), using 1500-mesh abrasive, pressure 0.6 MPa, and processing time 30 min;

[0031] The abrasive is composed of diamond micro powder, nano-silica, boron carbide particles, and butylene phthalate in a mass ratio of 3:1:1:1.

[0032] The roughing and polishing process specifically involves polishing with polishing compound W28.

[0033] The polishing paste specifically comprises the following raw materials in parts by weight: 200 parts stearic acid, 300 parts paraffin wax, 60 parts trimethylolpropane trimethacrylate, 110 parts polyethylene glycol, and 200 parts anhydrous ethanol.

[0034] The degreasing process specifically involves cleaning with a cleaning agent (anhydrous ethanol).

[0035] The dehydration process specifically involves drying with inert gas.

[0036] Example 2

[0037] A polishing process for a cemented carbide mold involves first degreasing and dewatering the cemented carbide mold, then rough polishing, and finally placing the cemented carbide mold in a sealed space for sandblasting and polishing.

[0038] Adjust the sandblasting and polishing process according to the roughness and / or hardness of the cemented carbide mold.

[0039] Specifically as follows:

[0040] The surface roughness of the cemented carbide mold is Ra0.2 (HRA85.8-86.8), using 2000-mesh abrasive, pressure 0.5 MPa, and processing time 20 min;

[0041] The abrasive is composed of diamond micro powder, nano-silica, boron carbide particles, and polystyrene in a mass ratio of 3:1:1:1.

[0042] The roughing and polishing process specifically involves polishing with polishing compound W28.

[0043] The polishing paste specifically comprises the following raw materials in parts by weight: 200 parts stearic acid, 300 parts paraffin wax, 60 parts trimethylolpropane trimethacrylate, 110 parts polyethylene glycol, and 200 parts anhydrous ethanol.

[0044] The degreasing process specifically involves cleaning with a cleaning agent (anhydrous ethanol).

[0045] The dehydration process specifically involves drying with inert gas.

[0046] Example 3

[0047] A polishing process for a cemented carbide mold involves first degreasing and dewatering the cemented carbide mold, then rough polishing, and finally placing the cemented carbide mold in a sealed space for sandblasting and polishing.

[0048] Adjust the sandblasting and polishing process according to the roughness and / or hardness of the cemented carbide mold.

[0049] Specifically as follows:

[0050] The surface roughness of the cemented carbide mold is Ra0.1 (HRA82.5-84.5), using 3000-mesh abrasive, pressure 0.4 MPa, and processing time 15 min.

[0051] The abrasive is composed of diamond micro powder, nano-silica, boron carbide particles, and polystyrene in a mass ratio of 3:1:1:1.

[0052] The roughing and polishing process specifically involves polishing with polishing compound W28.

[0053] The polishing paste specifically comprises the following raw materials in parts by weight: 200 parts stearic acid, 300 parts paraffin wax, 60 parts trimethylolpropane trimethacrylate, 110 parts polyethylene glycol, and 200 parts anhydrous ethanol.

[0054] The degreasing process specifically involves cleaning with a cleaning agent (anhydrous ethanol).

[0055] The dehydration process specifically involves drying with inert gas.

[0056] Comparative Example 1

[0057] A polishing process for a cemented carbide mold involves degreasing and dehydrating the mold. First, polishing compound W28 is used for rough polishing to remove rough textures. Then, polishing compound W20 is used, followed by polishing compound W14, then polishing compound W10 for fine polishing, then polishing compound W5 for mirror polishing, and finally polishing compound W2.5 for mirror polishing until a mirror finish is achieved. The process takes 6 hours.

[0058] Comparative Example 2

[0059] A polishing process for a cemented carbide mold involves first degreasing and dewatering the cemented carbide mold, then rough polishing, and finally placing the cemented carbide mold in a sealed space for sandblasting and polishing.

[0060] Adjust the sandblasting and polishing process according to the roughness and / or hardness of the cemented carbide mold.

[0061] The surface roughness of the cemented carbide mold is Ra0.4 (HRA86.5-88.0), using 1500-mesh abrasive, pressure 0.6 MPa, and processing time 50 min;

[0062] The abrasive is composed of diamond micro powder, nano-silica, and boron carbide particles in a mass ratio of 3:1:1:1.

[0063] The roughing and polishing process specifically involves polishing with polishing compound W28.

[0064] The polishing paste specifically comprises the following raw materials in parts by weight: 200 parts stearic acid, 300 parts paraffin wax, 60 parts trimethylolpropane trimethacrylate, 110 parts polyethylene glycol, and 200 parts anhydrous ethanol.

[0065] The degreasing process specifically involves cleaning with a cleaning agent (anhydrous ethanol).

[0066] The dehydration process specifically involves drying with inert gas.

[0067] Comparison table of time consumption for Examples 1-3 and Comparative Example 1

[0068] Sample Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Processing time 30min 20min 15min 6h 50min

[0069] As can be seen from the table above, the processing time is greatly shortened. In specific applications, the molds made using the polishing process described above have a service life at least twice that of the molds polished in Examples 1-3. The mold surfaces are smoother and more consistent. At the same time, the molds polished using Examples 1-3 have improved surface finish, significantly reduced defects in the pressed products, and noticeably improved surface quality. The pressing efficiency is also greatly improved. It also solves the problem that deep and small grooves cannot be manually polished in the traditional method, which leads to adhesion and mold rework during pressing. In addition, the analysis of Example 2 shows that the abrasive used in this example contains elastic polymer particles, which allows the inorganic particles to adhere to the surface of the polymer particles, forming a special structure with better polishing performance.

[0070] The embodiments described above are merely preferred embodiments of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various other corresponding changes and modifications based on the technical solutions and concepts described above, and all such changes and modifications should fall within the protection scope of the claims of the present invention.

Claims

1. A polishing process of a cemented carbide die, characterized in that, The cemented carbide die is first subjected to oil and water removal treatment, then subjected to roughening and polishing, and finally placed in a closed space for sand blasting and polishing. The sand blasting and polishing process is adjusted according to the roughness and hardness of the cemented carbide die. The sand blasting and polishing process is adjusted according to the roughness and hardness of the cemented carbide die, and the adjustment is as follows: When the surface roughness of the cemented carbide die is Ra 0.4-5 and HRA 86.5-88.0, 1400-1600 mesh abrasive, pressure 0.5-0.7 MPa, and processing time 20-40 min are used; When the surface roughness of the cemented carbide die is Ra 0.1-0.3 and HRA 85.8-86.8, 1800-2200 mesh abrasive, pressure 0.4-0.6 MPa, and processing time 10-30 min are used; When the surface roughness of the cemented carbide die is Ra 0.05-0.15 and HRA 82.5-84.5, 2800-3200 mesh abrasive, pressure 0.3-0.5 MPa, and processing time 10-20 min are used. The abrasive includes at least one of diamond powder, nano-silicon dioxide, and boron carbide particles, and further includes elastic polymer particles.

2. A polishing process of cemented carbide dies according to claim 1, characterized in that, The sand blasting and polishing process is adjusted according to the roughness and hardness of the cemented carbide die, and the adjustment is as follows: When the surface roughness of the cemented carbide die is Ra 0.4 and HRA 86.5-88.0, 1500 mesh abrasive, pressure 0.6 MPa, and processing time 30 min are used; When the surface roughness of the cemented carbide die is Ra 0.2 and HRA 85.8-86.8, 2000 mesh abrasive, pressure 0.5 MPa, and processing time 20 min are used; When the surface roughness of the cemented carbide die is Ra 0.1 and HRA 82.5-84.5, 3000 mesh abrasive, pressure 0.4 MPa, and processing time 15 min are used.

3. A polishing process for cemented carbide dies according to claim 1, characterized in that The elastic polymer particles include butylene terephthalate and / or polystyrene.

4. A polishing process for cemented carbide dies according to claim 1, characterized in that The roughening and polishing specifically uses polishing paste W20-40.

5. A polishing process of cemented carbide dies according to claim 4, characterized in that, The polishing paste specifically includes the following raw materials by weight: 100-300 parts of stearic acid, 200-400 parts of paraffin, 50-80 parts of trimethylolpropane trimethacrylate, 100-120 parts of polyethylene glycol, and 100-300 parts of anhydrous ethanol.

6. A polishing process for cemented carbide dies according to claim 1, characterized in that The oil removal specifically uses a cleaning agent for cleaning. The water removal specifically uses an inert gas for drying.