A manufacturing process for precision diamond rollers

Abstract

This invention discloses a manufacturing process for a precision diamond roller, belonging to the field of diamond roller technology. The process includes mold design and processing, internal electroplating, pretreatment, brazing material preparation, CVD strip embedding, brazing material coating, assembly and fixing of the negative mold cavity and the roller substrate, vacuum drying, gas-protected induction brazing, precision finishing, inspection, and packaging. In this application, diamonds are first placed in an orderly manner into the negative mold cavity using a template. Then, one end of the diamond particles is initially fixed in the negative mold cavity using internal electroplating. Finally, the other end of the diamond particles is embedded in the brazing material through brazing, achieving an orderly arrangement and high consistency of the diamond abrasive, thus improving the durability and precision of the roller.

Description

Technical Field

[0001] This invention belongs to the field of diamond rollers, and specifically relates to a manufacturing process for a precision diamond roller. Background Technology

[0002] Diamond rollers are a new generation of grinding wheel dressing tools, characterized by high precision and high formability. They are high-efficiency, long-life, and low-cost grinding wheel dressing tools used in special machine tools and gear grinding machines for mass production of profile grinding. CNC profile grinding technology is a rapidly developing new machining technology both domestically and internationally in recent years. Its highly efficient and precise machining methods have extremely wide applications in mechanical engineering. The working principle of diamond rollers is as follows: by being mounted on the dressing device of the grinding machine, the outline, precision, and dimensions of the diamond roller are copied onto the surface of the workpiece. Its advantages include simple machine operation, low skill requirements for operators, good consistency in product precision, stable quality, significantly improved production efficiency and product quality, reduced manufacturing costs, and easy automation of grinding processes.

[0003] CN11716580A uses a metal binder containing binder metals such as titanium powder, iron powder, and copper powder, giving it the characteristics of liquid-phase sintering, and skeleton metals such as tungsten powder and molybdenum powder. Then, it goes through processes such as mixing, feeding, sintering, and finishing. By using this process, through the rational configuration of each component raw material, the formed diamond roller has good hardness, toughness, and wear resistance.

[0004] CN114160798A ensures that diamond powder can form chemical bonds with the molten metal binder during the sintering process by reliably controlling the hot pressing sintering parameters. This improves the firmness of the diamond rollers and gives them high grinding efficiency. At the same time, by rationally selecting the composition of the metal binder, i.e. adjusting the ratio of copper powder, cobalt powder and iron powder, uniform distribution of diamond powder in the metal binder is achieved, preserving the hardness of the diamond powder itself, reducing wear during processing, and effectively improving the wear resistance and service life of the diamond rollers.

[0005] CN112621582A describes a process where a diamond roller blank is placed in a liquid carbide crucible. Elements diffuse to the workpiece surface and react with carbon in the steel to form a carbide layer. A laser beam irradiates the surface of the diamond roller, heating it to form a surface strengthening layer with certain properties, thereby improving its surface strength. This overcomes the problem that existing diamond roller blanks, obtained during sintering, have poor overall structural strength, leading to wear and even breakage during dressing. Then, the roller is repeatedly ground on a specialized dressing machine until it meets the finished product requirements, thus improving the quality of the finished diamond roller.

[0006] CN222371365U discloses a brazed diamond grinding wheel with protrusions, including a grinding wheel base. The grinding wheel base includes a frustum portion and an annular portion connected to each other, and the annular portion is coaxially arranged with the frustum portion. The working surface of the annular portion is provided with a plurality of grinding wheel protrusions protruding away from the frustum portion and a chip discharge groove for discharging grinding chips.

[0007] While the above-mentioned method, which enhances the metal binder's ability to hold abrasives through active elements, improves the tool's service life, the traditional sintering process is limited by low sintering temperature and limited sintering time. The active elements mainly react with diamond through a pure solid or semi-solid reaction process, which is insufficient and far from achieving the bonding strength between the binder and diamond provided by high-temperature brazing technology. Moreover, the error after manufacturing using this method is too large, so it must be corrected, which takes a lot of time.

[0008] Literature on the standardization of automated production process for diamond rollers, determination of manufacturing process factors for diamond rollers, and manufacturing and application of diamond rollers introduces the process flow of manufacturing diamond rollers using internal and external electroplating methods, as well as the advantages and disadvantages of this process method.

[0009] Rollers manufactured by internal plating have higher precision than those manufactured by external plating, but the process is longer, and the increased plating thickness leads to increased stress and deformation.

[0010] External plating is a simple process, the substrate is easy to process, the electroplating stress is low, and the cost is lower than internal plating. However, the forming accuracy of external plating largely depends on the uniformity of diamond particle size. The inhomogeneity of diamond particle size and the finishing problems after electroplating are the fundamental issues affecting the accuracy of externally plated rollers.

[0011] While high-temperature brazing technology offers unparalleled bonding strength between the binder and diamond, and high sharpness of the grinding wheel—requiring only 20%–30% diamond coverage to achieve high strength, resulting in high diamond exposure, large cutting space, more and sharper cutting edges, and significantly reduced grinding energy—there are several drawbacks. During the brazing process, diamonds are typically randomly distributed and disordered. Furthermore, the melting of the solder during heating causes diamonds to float and move, leading to problems such as diamond segregation and inconsistent height. This necessitates significant time for finishing, resulting in low production efficiency. Additionally, the process subjectes diamonds to impact and wear, leading to excessive wear, and the finishing process reduces diamond sharpness, severely impacting tool performance and lifespan.

[0012] In summary, internal electroplating is typically used for high-precision and complex surface finishing, achieving high precision with little or no subsequent finishing. Currently, in the production process of brazed diamond rollers, there are issues such as uneven diamond distribution, which reduces the wear resistance of the diamond roller and the finishing effect on the grinding wheel; inconsistent abrasive grain height, etc., requiring roller finishing to ensure that the abrasive grain height and surface roughness meet the requirements. However, the subsequent finishing process is time-consuming and causes significant damage to the diamond.

[0013] To address the aforementioned issues, this invention utilizes a hole template method combined with an internal electroplating process to achieve a regular arrangement of diamond particles and a uniform height distribution. Subsequent adjustments are minimal or nonexistent, resulting in virtually no wear on the diamonds. The regularly arranged diamonds minimize clogging during grinding, ensuring a smooth grinding process, reducing noise, and improving the durability and precision of the grinding rollers. The diamonds electroplated onto the negative mold cavity are coated with nickel, preventing them from shifting and floating at high temperatures, thus preventing disordered arrangement and inconsistent heights. An inert gas-protected induction brazing process achieves a strong chemical-metallurgical bond between the brazing filler metal and the diamond particles, reducing or eliminating oxidation of the diamond and the metal binder. Compared to simple inlay coating, this significantly improves the holding force of the metal binder on the diamonds. Induction heating is rapid and allows for localized heating, reducing heat input to the substrate and minimizing thermal damage. Heat treatment during cooling reduces or eliminates stress in the substrate, restoring the workpiece to near its original state while saving energy. Summary of the Invention

[0014] This invention addresses the problems in current diamond roller manufacturing processes, such as disordered diamond particle arrangement, chip buildup during grinding, high grinding temperatures, workpiece thermal deformation, burns, and cracks; and inconsistent diamond particle height, resulting in long post-processing times and severe diamond wear. It proposes a precision diamond roller manufacturing process. This invention achieves regular particle arrangement through a hole template method, combined with internal electroplating, resulting in high-precision rollers with minimal or no post-processing. Induction brazing provides rapid heating and high metallurgical bonding strength. Therefore, rollers manufactured using this process exhibit high production efficiency, regular diamond arrangement, high surface accuracy and bonding strength, wear resistance, and long service life.

[0015] To achieve the above objectives, the present invention adopts the following technical solution: A manufacturing process for a precision diamond roller is as follows: (1) Make a negative model cavity and a hole template according to the shape of the diamond roller. The hole template has several through holes that are consistent with the arrangement of diamond particles. The side of the hole template that contacts the negative model cavity has several protrusions of the same height. (2) The diamond particles are placed into the plating area inside the negative mold cavity through the through hole of the template, and one end of the diamond particles is initially fixed in the negative mold cavity by electroplating a metal coating. (3) Dip the CVD strip in the brazing material and insert it into the gap of the outer circle of the roller substrate. Apply a certain thickness of brazing material to the working area of ​​the roller and scrape it flat to obtain the brazing coating layer. (4) Assemble the negative mold cavity from step (2) with the roller from step (3) so that the other end of the diamond particle is embedded in the brazing material, fix it, and dry it. (5) In a protective atmosphere, the working area of ​​the roller is heated and brazed. When the brazing material on the surface of the roller substrate melts, mechanical vibration is applied to the roller. When heating is stopped, vibration is also stopped. (6) Remove the negative mold cavity from the roller after step (5) to expose the diamond particles on the surface and obtain a diamond roller blank. Then, precisely trim it until it meets the requirements of the finished product.

[0016] Further, in step (1), the material of the negative mold cavity is graphite or metal, the material of the hole template is plastic, the accuracy of the negative mold cavity is ±0.005mm, the thickness of the hole template is 3~8mm, the height of the protrusion on the hole template is 30%~50% of the diamond particle size, and the diamond particle size < the diameter of the through hole on the hole template < twice the diamond particle size.

[0017] Further, in step (2), the surface of the diamond particles is plated with titanium or chromium, and the particle size of the diamond particles is 212~1000μm; the thickness of the metal coating is 2~5% of the particle size of the diamond particles.

[0018] Further, in step (3), the brazing material is obtained by mixing brazing filler metal and binder, wherein the brazing filler metal accounts for 90~95wt% and the binder accounts for 5~10wt%.

[0019] Furthermore, the solder is a chromium-containing nickel-based solder or a Cu-Sn-Ti solder, with a particle size of 200-300 mesh and a melting temperature range of 900-1050℃. The preferred chromium-containing nickel-based solders are BNi82CrSiFeB (BNi-2) or BNi76Cr14P10 (BNi-7); the preferred Cu-Sn-Ti solders are Cu-15Sn-10Ti or Cu-10Sn-5Ti alloys.

[0020] Further, in step (3), the CVD strip has a side gap of 0.03~0.1mm in the groove around the roller; the brazing coating thickness is 25~40% of the diamond particle size.

[0021] Furthermore, in step (4), the drying temperature is 80~95℃ and the drying time is 30~120min.

[0022] Further, in step (5), the heating temperature is 950~1100℃, the heating time is 5~8s, the vibration frequency is 15~25Hz, and the amplitude is 0.5~2 mm; after the heating is stopped, when the roller cools down to 650~850℃, the roller is quenched, and then tempered at 200~300℃ for 30~90 min.

[0023] Specifically, the present invention includes the following steps: (1) Mold design and processing: The negative mold cavity is made according to the shape of the diamond roller, and then the hole template with the same shape as the negative mold cavity is made. The side of the hole template that contacts the negative mold cavity is provided with several through holes and several protrusions with the same height as the diamond particles. (2) Internal electroplating: Before electroplating, the diamond and the negative mold cavity are degreased, impurities are removed and acid pickling is activated. The unplated area of ​​the negative mold cavity is insulated and protected. The hole template is placed and the two are fixed. The diamond particles are filled into the through holes of the hole template. The diamond particles fall into the plating area in the negative mold cavity through the through holes. Then, the nickel layer is plated in the plating area in the negative mold cavity by electrochemical deposition, so that the diamond particles are fixed in the negative mold cavity. (3) Pretreatment: Clean the roller after finishing to remove oil and impurities, protect the working area of ​​the roller, and then apply a layer of high temperature refractory mud around its inner ring to prevent the brazing filler metal from flowing erratically during high temperature heating. (4) Preparation of brazing coating material: After designing the ratio of brazing filler metal and binder, weigh each component according to the ratio, and then mix them using mechanical stirring for later use; The brazing filler metal comprises 90-95% by mass percentage, and the adhesive comprises 5-10%. The brazing filler metal is a nickel-based or copper-based filler metal with a particle size of 200-300 mesh and a melting temperature range of 900-1050℃; the binder is a polymer solvent, for example, the binder from Lucos Brazing Materials (Suzhou) Co., Ltd., model: Handy Flo 660; (5) CVD strip embedding and brazing material coating: The laser-cut CVD strip is dipped in brazing material and embedded into the gap of the roller substrate tip (outer circle) by manual implantation. Then, a certain thickness of brazing material is coated on the working area of ​​the roller and smoothed with a polytetrafluoroethylene scraper. (6) Assembly and fixation of the negative mold cavity and the roller base: Assemble the negative mold cavity coated with diamond and the roller coated with brazing material, so that the diamond is embedded in the brazing material. After adjusting the distance, fix it with tooling fixtures. (7) Vacuum drying: Place the assembled and fixed rollers into a vacuum drying oven for drying; (8) Gas shielded induction brazing: In a protective atmosphere, a high-frequency induction welding machine is used to heat the working area of ​​the roller. The maximum temperature of the roller surface is 950~1100℃ and the holding time is 5~8s. During this period, when the brazing material on the surface of the roller substrate melts, mechanical vibration is applied to the roller. When heating is stopped, vibration is also stopped. At the same time, the brazing of the CVD strip to the roller substrate and the diamond particles to the roller substrate is completed. When cooled to 650~850℃, the roller is quenched and tempered at 200~300℃. The tempering holding time is 30~90min. Furthermore, the protective atmosphere is argon; the quenching fluid is quenching oil; (9) Precision finishing: After heat treatment, the material of the reverse negative mold cavity of the roller is removed so that the diamond particles are exposed on the surface to obtain a diamond roller blank. Then, the deviation value is initially measured by instruments such as Zeiss coordinate measuring machine, Taylor instrument, and universal display, and the appropriate finishing allowance is calculated. The roller is repeatedly ground on a special finishing machine until it meets the requirements of the finished product. The dimensional accuracy of the diamond roller blank is approximately 0.003~0.015mm different from the theoretical deviation of the finished diamond roller. (10) Inspection and packaging: The diamond rollers that have been precision-dressed are subjected to strict inspection. The finished diamond rollers that are qualified are sprayed with anti-rust oil and wrapped with protective film, then sealed and put into storage.

[0024] The present invention has the following beneficial effects: 1) An additional hole template is added during the internal electroplating process to achieve a regular and orderly arrangement of diamonds. This prevents clogging during grinding and ensures a smooth grinding process, thereby improving the durability and precision of the roller.

[0025] 2) Diamond roller blanks manufactured by internal electroplating have high dimensional accuracy and no fundamental errors caused by different diamond particle sizes or fixed heights. They have consistent height and higher surface accuracy. This method is simple, efficient, low in production cost, and requires no post-processing or only requires a small amount of fine finishing.

[0026] 3) After electroplating, the diamond is coated with nickel. Nickel has a melting point of 1453℃ and a maximum heating temperature of 1100℃. Therefore, the problem of the diamond moving or floating due to nickel melting will not occur, and the diamond can maintain an orderly arrangement and high consistency.

[0027] 4) The brazing materials used are BNi82CrSiFeB (BNi-2) or BNi76Cr14P10 (BNi-7) alloys, Cu-15Sn-10Ti or Cu-10Sn-5Ti alloys, etc. In these brazing materials, elements such as Cr or Ti form a carbide layer through chemical reaction with the diamond surface, thereby achieving a strong metallurgical bond between the diamond and the metal matrix.

[0028] 5) Induction heating is fast and can achieve localized heating with low heat input to the substrate.

[0029] 6) After the rollers are brazed, the quenching heat treatment is completed simultaneously during the cooling process, which greatly saves the energy required for heating and has the characteristics of energy saving, emission reduction and green environmental protection. Attached Figure Description

[0030] Figure 1 This is a flowchart of the manufacturing process of the present invention; Figure 2 This is a schematic diagram of the roller base; Figure 3 This is a schematic diagram of the hole template structure; Figure 4 This is a schematic diagram of the assembly of the female model cavity (colored in green) and the hole template (colored in blue); Figure 5 A schematic diagram showing the roller substrate after being inlaid with CVD strips, coated with brazing material (colored in yellow), and coated with high-temperature refractory putty (colored in red); Figure 6 This is a schematic diagram of the assembly of the female model cavity and the roller base. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments: Example 1 A manufacturing process for precision diamond rollers, such as Figure 1 As shown, the process is as follows: A: According to the designed dimensions of the roller base (the shape of the roller base is as follows) Figure 2 (As shown) Precision machined contoured stainless steel metal female mold cavity (hereinafter referred to as female mold cavity, shape as shown) Figure 4 As shown in the diagram, a PTFE plate with a hole template is used. The cavity accuracy of the negative mold is ±0.005mm. Then, degreasing, impurity removal, and oxide layer removal are performed. Uncoated areas are sealed and protected with insulating paper. Through holes are machined on the PTFE plate according to the diamond size and arrangement (see schematic diagram of the hole template). Figure 3 As shown in the figure, the diamond particle size is 850~950μm, the diameter of the through hole in the template is 1000μm, and the thickness of the template is 3mm.

[0032] The side of the hole template that contacts the female mold cavity has evenly distributed protrusions to control the distance between them, and the height of the protrusions is 400μm.

[0033] B: Etching of the negative model cavity with 5wt% H2SO4 at room temperature for 2-3 min and diamond particles (with PdCl2 concentration of 0.2-0.5 g / L and commercially available concentrated HCl added at 10 g / L) The process involves acid pickling and activation in a mixed solution (mL / L, held at room temperature for 10 min). The hole template and negative mold cavity are then fixed in place using a fixture and immersed in the electroplating solution. Diamond is then sprinkled into the through-holes of the hole template, spreading and pressing to ensure that each through-hole contains diamond and is in contact with the negative mold cavity. Nickel is then plated into the negative mold cavity using electrochemical deposition. Specifically, the formulation in paragraph 71 of patent ZL201510608273.9 can be used, where the electroplating solution contains the following components at the following concentrations: nickel sulfamate 320 g / L, nickel chloride 30 g / L, boric acid 40 g / L, sodium dodecyl sulfate 0.04 g / L, and 1,4-butynediol 0.5 g / L; the pH of the electroplating solution is 4.2, the temperature is 40℃, and the current density is 1.5 A·dm³. -2 After electroplating, the diamond is coated with a layer thickness of 35μm. After plating, it is cleaned with water and dried for later use.

[0034] C: Clean the finished roller base to remove oil and impurities, then cover the working area of ​​the roller with plastic wrap, such as... Figure 5 As shown, a layer of high-temperature refractory mortar (model AL-70M, manufacturer: Jiashan Yourui Refractory Materials Co., Ltd.) is applied around the inner ring to prevent the brazing filler metal from flowing erratically during high-temperature brazing heating. D: Mix 95% Ni-based solder and 5% binder evenly using a mixer according to mass fraction and set aside; The Ni brazing filler metal is BNi82CrSiFeB (BNi-2), with a melting point of 1020~1050℃ and a particle size of 200~250 mesh. The binder is purchased from Lucos Brazing Materials (Suzhou) Co., Ltd., model: Handy Flo 660.

[0035] E: Using artificial implantation, such as Figure 5 As shown, a laser-cut CVD strip is dipped in nickel-based brazing material and inserted into the gap of the outer ring of the roller substrate. Then, a layer of nickel-based brazing filler is coated on both sides of the roller substrate and smoothed with a polytetrafluoroethylene scraper to a thickness of 300μm.

[0036] F: such as Figure 6 As shown, the distance between the negative mold cavity and the working area of ​​the roller base is adjusted using a tooling fixture to make them parallel to each other before fixing them. The diamond particles in the negative mold cavity are embedded in the nickel-based brazing material.

[0037] G: Use a vacuum drying oven to dry the brazing material on the rollers at a temperature of 80°C for 30 minutes.

[0038] H: Under an argon atmosphere, the roller substrate to be welded is heated in the argon atmosphere using a high-frequency induction welding machine with a contour coil (the coil shape is consistent with the roller shape) to heat the working area of ​​the roller substrate. The highest temperature of the roller surface is 1070℃, the holding time is 8s, and when cooled to 830℃, it is quenched with quenching oil, tempered at 300℃, and the tempering holding time is 30min.

[0039] During induction heating, when the nickel-based brazing filler metal BNi82CrSiFeB (BNi-2) on the surface melts, mechanical vibration is applied to the roller; preferably, the vibration frequency is 20Hz and the amplitude is 1mm, and the vibration is stopped when heating is stopped.

[0040] I: The stainless steel reverse-cathode mold cavity material of the heat-treated roller is removed. The dimensional accuracy of the diamond roller blank and the finished diamond roller are measured by Zeiss coordinate measuring machine. The deviation is about 0.010mm. Then, it is repeatedly ground on a special dressing machine until it meets the requirements of the finished product.

[0041] G: Inspection and Packaging: The diamond rollers that have undergone grinding and polishing are subjected to strict inspection. Qualified diamond rollers are sprayed with anti-rust oil and wrapped with protective film, then sealed in boxes and put into storage.

[0042] Example 2 A manufacturing process for precision diamond rollers, such as Figure 1 As shown, the process is as follows: A: According to the designed dimensions of the roller base (the shape of the roller base is as follows) Figure 2 (As shown) Precision machined contoured stainless steel metal female mold cavity (hereinafter referred to as female mold cavity, shape as shown) Figure 4 As shown in the diagram, a PTFE plate with a hole template is used. The cavity accuracy of the negative mold is ±0.005mm. Then, degreasing, impurity removal, and oxide layer removal are performed. Uncoated areas are sealed and protected with insulating paper. Through holes are machined on the PTFE plate according to the diamond size and arrangement (see schematic diagram of the hole template). Figure 3 As shown in the figure, the diamond particle size is 850~950μm, the diameter of the through hole in the template is 1000μm, and the thickness of the template is 3mm.

[0043] The side of the hole template that contacts the female mold cavity has evenly distributed protrusions to control the distance between them, and the height of the protrusions is 400μm.

[0044] B: The negative mold cavity (etched with 5wt% H2SO4 at room temperature for 2-3 min) and diamond particles (carried in a mixed solution of PdCl2 concentration of 0.2-0.5 g / L and commercially available concentrated HCl added at 10 mL / L, for 10 min at room temperature) are acid-washed and activated. The hole template and negative mold cavity are fixed with a fixture and placed in the electroplating solution. Then, diamond is sprinkled into the through holes of the hole template, spread and pressed to fill to ensure that each through hole contains diamond and is in contact with the negative mold cavity. Nickel is plated into the cavity using an electrochemical deposition method. Specifically, the formula in paragraph 71 of the specification of patent ZL201510608273.9 can be used. The nickel layer grows continuously, covering the diamond, and the coating thickness is 35μm. After the coating is completed, it is cleaned with water and dried for later use.

[0045] C: Clean the roller base after fine machining to remove oil and impurities, then wrap the working area of ​​the roller with plastic wrap and apply a layer of high-temperature refractory mud (model AL-70M, manufacturer: Jiashan Yourui Refractory Materials Co., Ltd.) around its inner ring to prevent the brazing filler metal from flowing erratically when the brazing heating is at high temperature. D: By mass fraction, mix 95% Cu-Sn-Ti solder and 5% binder evenly using a mixer and set aside. The Cu-Sn-Ti brazing filler metal is Cu-10Sn-5Ti (i.e., Sn accounts for 10% of the total mass and Ti accounts for 5% of the total mass), with a melting point of 900~930℃ and a particle size of -300 mesh. The binder is purchased from Lukos Brazing Materials (Suzhou) Co., Ltd., model: Handy Flo 660.

[0046] E: Using a manual implantation method, the laser-cut CVD strip is dipped in Cu-10Sn-5Ti brazing material and inserted into the gap of the outer ring of the roller substrate. Then, a layer of Cu-10Sn-5Ti brazing filler is coated on both sides of the roller substrate and smoothed with a polytetrafluoroethylene scraper to a thickness of 300μm.

[0047] F: Use tooling fixtures to adjust the distance between the negative mold cavity and the working area of ​​the roller base, make them parallel to each other and then fix them. The diamond particles in the negative mold cavity are embedded in Cu-10Sn-5Ti brazing material.

[0048] G: Use a vacuum drying oven to dry the brazing material on the rollers at a temperature of 80°C for 30 minutes.

[0049] H: Under an argon atmosphere, the roller substrate to be welded is heated in argon atmosphere using a high-frequency induction welding machine with a contour coil (the coil shape is consistent with the roller shape) to heat the working area of ​​the roller substrate. The highest temperature of the roller surface is 950℃, the holding time is 6s, and when cooled to 720℃, it is quenched with quenching oil, tempered at 260℃, and the tempering holding time is 30min.

[0050] During induction heating, mechanical vibration is applied to the roller when the copper-based brazing filler metal on the surface melts; preferably, the vibration frequency is 10Hz and the amplitude is 0.5mm, and the vibration is stopped when heating is stopped.

[0051] I: The stainless steel reverse-cathode mold cavity material of the heat-treated roller is removed. The dimensional accuracy of the diamond roller blank and the finished diamond roller are measured by Zeiss coordinate measuring machine. The deviation is about 0.010mm. Then, it is repeatedly ground on a special dressing machine until it meets the requirements of the finished product.

[0052] G: Inspection and Packaging: The diamond rollers that have undergone grinding and polishing are subjected to strict inspection. Qualified diamond rollers are sprayed with anti-rust oil and wrapped with protective film, then sealed in boxes and put into storage.

[0053] Example 3 A manufacturing process for precision diamond rollers, such as Figure 1 As shown, the process is as follows: A: According to the designed dimensions of the roller base (the shape of the roller base is as follows) Figure 2 (As shown) Precision machined contoured stainless steel metal female mold cavity (hereinafter referred to as female mold cavity, shape as shown) Figure 4 As shown in the diagram, a PTFE plate with a hole template is used. The cavity accuracy of the negative mold is ±0.005mm. Then, degreasing, impurity removal, and oxide layer removal are performed. Uncoated areas are sealed and protected with insulating paper. Through holes are machined on the PTFE plate according to the diamond size and arrangement (see schematic diagram of the hole template). Figure 3 As shown in the figure, the diamond particle size is 300~355μm, the diameter of the through hole in the template is 400μm, and the thickness of the template is 3mm.

[0054] The side of the hole template that contacts the female mold cavity has evenly distributed protrusions to control the distance between them, and the height of the protrusions is 150μm.

[0055] B: The negative mold cavity (etched with 5wt% H2SO4 at room temperature for 2-3 min) and diamond particles (carried in a mixed solution of PdCl2 concentration of 0.2-0.5 g / L and commercially available concentrated HCl added at 10 mL / L, for 10 min at room temperature) are acid-washed and activated. The hole template and negative mold cavity are fixed with a fixture and placed in the electroplating solution. Then, diamond is sprinkled into the through holes of the hole template, spread and pressed to fill to ensure that each through hole contains diamond and is in contact with the negative mold cavity. Nickel is plated into the negative mold cavity by electrochemical deposition. Specifically, the formula in paragraph 71 of the specification of patent ZL201510608273.9 can be used. The nickel layer grows continuously, covering the diamond. The coating thickness is 15μm. After the coating is completed, it is cleaned with water and dried for later use.

[0056] C: Clean the precision-machined roller base to remove oil and impurities, then wrap the working area of ​​the roller base with plastic wrap and apply a layer of high-temperature refractory mud (model AL-70M, manufacturer: Jiashan Yourui Refractory Materials Co., Ltd.) around its inner ring to prevent the brazing filler metal from flowing erratically when the brazing heating is at high temperature. D: By mass fraction, mix 95% Cu-Sn-Ti solder and 5% binder evenly using a mixer and set aside. The Cu-Sn-Ti solder is Cu-10Sn-5Ti, with a melting point of 900℃~930℃ and a particle size of -300 mesh.

[0057] E: Using a manual implantation method, the laser-cut CVD strip is dipped in Cu-10Sn-5Ti brazing material and inserted into the gap of the outer ring of the roller substrate. Then, a layer of Cu-10Sn-5Ti brazing filler is coated on both sides of the roller substrate and smoothed with a polytetrafluoroethylene scraper to a thickness of 300μm.

[0058] F: Use tooling fixtures to adjust the distance between the negative mold cavity and the working area of ​​the roller base, make them parallel to each other and then fix them. The diamond particles in the negative mold cavity are embedded in Cu-10Sn-5Ti brazing material.

[0059] G: Use a vacuum drying oven to dry the brazing material on the rollers at a temperature of 80°C for 30 minutes.

[0060] H: Under an argon atmosphere, the roller substrate to be welded is heated in argon using a high-frequency induction welding machine with a contour coil (the coil shape is consistent with the roller shape) to heat the working area of ​​the roller. The highest surface temperature of the roller is 950℃, and the holding time is 6s. When cooled to 720℃, quenching oil is used for quenching, and tempering is performed at 260℃ for 30min.

[0061] During induction heating, mechanical vibration is applied to the roller when the copper-based brazing filler metal on the surface melts; preferably, the vibration frequency is 10Hz and the amplitude is 0.5mm, and the vibration is stopped when heating is stopped.

[0062] I: The stainless steel reverse-cathode mold cavity material of the heat-treated roller is removed. The dimensional accuracy of the diamond roller blank and the finished diamond roller are measured by Zeiss coordinate measuring machine. The deviation is about 0.010mm. Then, it is repeatedly ground on a special dressing machine until it meets the requirements of the finished product.

[0063] G: Inspection and Packaging: The diamond rollers that have undergone grinding and polishing are subjected to strict inspection. Qualified diamond rollers are sprayed with anti-rust oil and wrapped with protective film, then sealed in boxes and put into storage.

[0064] Comparative Examples 1-3: Under the same conditions as in Examples 1, 2, and 3, single-layer diamond grinding wheels were prepared by vacuum brazing. The vacuum brazing process parameters were referenced from Example 1 of Chinese Patent CN107326364B. The performance data of the diamond rollers obtained in the examples and comparative examples are shown in Table 1.

[0065] Table 1. Comparison of performance data between composite electroplating / induction brazing and vacuum brazing diamond rollers. Note: The lifespan of the roller in each embodiment is calculated based on the lifespan of the roller in the corresponding comparative example. For example, the lifespan of the roller in Embodiment 1 is 1.18 times that of the roller in Comparative Example 1.

[0066] As shown in Table 1, the diamond roller prepared in this application exhibits a shorter diamond wear and dressing time. Under the same conditions, the lifespan of the dressed alumina ceramic grinding wheel is longer than that of the vacuum-brazed diamond roller in Comparative Example 1. This is because the particle size of diamonds of the same grit size according to national standards is not entirely consistent. For example, the particle size range of 18 / 20 grit is 850~1000μm, with a maximum difference of 150μm, which greatly affects the accuracy of the roller. During the brazing process, some diamond abrasive grains float to the surface due to the melting of the alloy brazing filler metal, failing to make direct contact with the matrix. These issues result in the tips of the diamond abrasive grains in the vacuum-brazed diamond roller not being at the same height, thus reducing accuracy. To improve the accuracy of the vacuum-brazed roller, it is necessary to perform precision grinding and dressing after brazing. Diamond abrasive grains are used for crushing and removing material. During the dressing process, the diamonds are subjected to impact and wear, leading to excessive wear. Dressing also reduces the sharpness of the diamonds, which seriously affects the performance and lifespan of the tool. Irregularly arranged diamond abrasive grains tend to accumulate grinding debris between the grains during grinding, reducing grinding efficiency. Furthermore, the high temperatures generated during grinding can cause problems such as thermal deformation, burning, and cracking of the workpiece. Regularly arranged diamond abrasive grains, on the other hand, are less prone to clogging during grinding, resulting in a smoother grinding process, reduced noise, and improved roller durability and precision.

Claims

1. A manufacturing process for a precision diamond roller, characterized in that, The process is as follows: (1) Make a negative model cavity and a hole template according to the shape of the diamond roller. The hole template has several through holes that are consistent with the arrangement of diamond particles. The side of the hole template that contacts the negative model cavity has several protrusions of the same height. (2) The diamond particles are placed into the plating area inside the negative mold cavity through the through hole of the template, and one end of the diamond particles is initially fixed in the negative mold cavity by electroplating a metal coating. (3) Dip the CVD strip in the brazing material and insert it into the gap of the outer circle of the roller substrate. Apply a certain thickness of brazing material to the working area of ​​the roller and scrape it flat to obtain the brazing coating layer. (4) Assemble the negative mold cavity from step (2) with the roller from step (3) so that the other end of the diamond particle is embedded in the brazing material, fix it, and dry it. (5) In a protective atmosphere, the working area of ​​the roller is heated and brazed. When the brazing material on the surface of the roller substrate melts, mechanical vibration is applied to the roller. When heating is stopped, vibration is also stopped. (6) Remove the negative mold cavity from the roller after step (5) to expose the diamond particles on the surface and obtain a diamond roller blank. Then, precisely trim it until it meets the requirements of the finished product.

2. The manufacturing process of the precision diamond roller according to claim 1, characterized in that, In step (1), the material of the female mold cavity is graphite or metal, the material of the hole template is plastic, the accuracy of the female mold cavity is ±0.005mm, the thickness of the hole template is 3~8mm, the height of the protrusion on the hole template is 30%~50% of the diamond particle size, and the diamond particle size < the diameter of the through hole on the hole template < twice the diamond particle size.

3. The manufacturing process of the precision diamond roller according to claim 1, characterized in that, In step (2), the surface of the diamond particles is plated with titanium or chromium, and the particle size of the diamond particles is 212~1000μm; the thickness of the metal coating is 2~5% of the particle size of the diamond particles.

4. The manufacturing process of the precision diamond roller according to claim 1, characterized in that, In step (3), the brazing material is obtained by mixing brazing filler metal and binder. In the brazing material, brazing filler metal accounts for 90-95 wt% and binder accounts for 5-10 wt%.

5. The manufacturing process of the precision diamond roller according to claim 4, characterized in that, The solder is a nickel-based solder containing chromium or a Cu-Sn-Ti solder, with a particle size of 200~300 mesh and a melting temperature range of 900~1050℃.

6. The manufacturing process of the precision diamond roller according to claim 1, characterized in that, In step (3), the CVD strip has a side gap of 0.03~0.1 mm in the groove around the roller; the brazing coating thickness is 25~40% of the diamond particle size.

7. The manufacturing process of the precision diamond roller according to claim 1, characterized in that, In step (4), the drying temperature is 80~95℃ and the drying time is 30~120min.

8. The manufacturing process of the precision diamond roller according to claim 1, characterized in that, In step (5), the heating temperature is 950~1100℃, the heating time is 5~8s, the vibration frequency is 15~25 Hz, and the amplitude is 0.5~2 mm. After heating is stopped, when the roller cools down to 650~850℃, the roller is quenched and then tempered at 200~300℃ for 30~90 min.

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