Manufacturing process of precise diamond roller

Abstract

The invention discloses a manufacturing process of a precise diamond roller, which belongs to the technical field of diamond rollers and comprises the procedures of mold design and processing, internal electroplating, pretreatment, braze coating material preparation, CVD (chemical vapor deposition) strip inlaying, braze coating material coating, assembling and fixing of a female mold cavity and a roller base body, vacuum drying, gas shield induction braze welding, precise finishing, detection and packaging and the like. According to the method, the diamonds sequentially fall into the female die cavity through the hole template, then one ends of the diamond particles are preliminarily fixed into the female die cavity through the internal electroplating method, and finally the other ends of the diamond particles are embedded into the braze coating material through braze welding, so that ordered arrangement and high consistency of the diamond abrasives are achieved, and the quality of the diamond abrasives is improved. And the durability and the precision of the roller are improved.

Description

Technical Field

[0001] The invention belongs to the field of diamond rollers, and in particular relates to a manufacturing process of a precision diamond roller. Background Art

[0002] Diamond roller is a new generation of grinding wheel dressing tool with high precision and high forming characteristics. It is a high-efficiency, long-life, low-cost grinding wheel dressing tool used in special machine tools for large-scale forming grinding and gear grinding. CNC profile grinding is a new machining technology that has rapidly developed both domestically and internationally in recent years. Its efficient and precise machining methods have found widespread application in mechanical engineering. The diamond roller operates by being mounted on a grinding machine's dressing device, where it replicates the roller's contour, precision, and dimensions onto the surface of the part being machined. This process is characterized by its ease of operation and minimal operator skill requirements. The resulting products offer consistent precision and stable quality, significantly improving production efficiency and quality, reducing manufacturing costs, and facilitating automated grinding operations.

[0003] CN11716580A uses a metal binder including bonding material metals: titanium powder, iron powder, copper powder, so that it has the characteristics of liquid phase sintering, and skeleton material metals: tungsten powder, molybdenum powder, etc.; then it carries out mixing, feeding, sintering, trimming and other processes; the use of this process prepares the diamond roller with good hardness, toughness and wear resistance through the reasonable configuration of each component raw material.

[0004] CN114160798A ensures that diamond powder can chemically bond with the molten metal binder during the sintering process through reliable control of hot pressing sintering parameters, thereby improving the firmness of the diamond roller and achieving higher grinding efficiency. At the same time, through the reasonable selection of the metal binder composition, that is, the adjustment of the ratio of copper powder, cobalt powder and iron powder, the diamond powder is evenly distributed in the metal binder, the inherent hardness of the diamond powder is retained, the wear during the processing is reduced, and the wear resistance and service life of the diamond roller are effectively improved.

[0005] CN112621582A places a diamond roller blank into a carbide liquid crucible, where the elements diffuse to the workpiece surface and react with carbon in the steel to form a carbide layer. The laser beam irradiates the surface of the diamond roller to heat it up, thereby forming a surface strengthening layer with certain properties, thereby improving its surface strength. This overcomes the problem that the overall structural strength of the diamond roller blank obtained during the sintering and molding process of the existing diamond roller is poor, which causes the roller to be easily worn or even broken during the finishing process. Then, it is repeatedly ground on a special finishing machine until it meets the finished product requirements, thereby achieving the purpose of improving the finished product quality of the diamond roller.

[0006] CN222371365U discloses a brazed diamond grinding wheel with protrusions, which includes 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 bosses protruding away from the frustum portion and a chip discharge groove for discharging grinding chips.

[0007] Although the above-mentioned method of enhancing the metal bond's ability to hold abrasives through active elements improves the tool's service life, due to the limitations of the traditional sintering process, which has low sintering temperature and limited sintering time, the active elements mainly interact with diamonds through a pure solid or semi-solid reaction process and the reaction is not sufficient, far from reaching the level of bond strength between the bond and diamond provided by high-temperature brazing technology. In addition, the error after manufacturing using this method is too large, so trimming is necessary, and the trimming takes a lot of time.

[0008] The literature such as the finalization of the automated production process of diamond rollers, the determination of the manufacturing process factors of diamond rollers, and the manufacture and application of diamond rollers introduces the process flow of manufacturing diamond rollers using the internal and external electroplating method, as well as the advantages and disadvantages of this process method.

[0009] The rollers manufactured by the internal plating method have higher precision than those manufactured by the external plating method, but the process is longer, and the increase in the thickness of the coating increases the stress and deformation.

[0010] The external plating method is simple to process, the substrate is easy to machine, the electroplating stress is low, and the cost is lower than the internal plating method. The forming accuracy of the external plating method depends largely on the uniformity of the diamond particle size. The unevenness of diamond particle size and the problem of finishing after electroplating are the fundamental issues affecting the accuracy of the external plating roller.

[0011] High-temperature brazing technology offers unmatched bonding strength between the binder and diamond, and high sharpness of the grinding wheel compared to other processes. Diamonds only require a 20% to 30% coverage rate to achieve high strength, a high diamond exposure rate, a large cutting space, more and sharper cutting edges, and a significantly reduced grinding specific energy. However, during the brazing of diamond tools, diamonds are typically randomly distributed and disordered. Furthermore, the melting of the solder during heating causes the diamonds to float and move, ultimately leading to problems such as diamond segregation and height inconsistency. This requires significant time for trimming, resulting in low production efficiency, impact and wear on the diamonds, and excessive wear. Trimming also reduces the sharpness of the diamonds, seriously impacting the performance and life of the tools.

[0012] In summary, internal electroplating is usually used for the finishing of high-precision and complex surfaces, and only a small amount of subsequent finishing is required to achieve high precision; currently in the production process of brazed diamond rollers, there is an uneven distribution of diamonds, which reduces the wear resistance of the diamond rollers and the finishing effect on the grinding wheel; there are problems such as inconsistent abrasive contours, and the rollers need to be dressed to ensure that their abrasive contours and surface roughness meet the requirements. The subsequent dressing time is long and causes great damage to the diamonds.

[0013] To solve the above problems, the present invention uses a hole template method combined with an internal electroplating process to achieve a regular arrangement of diamonds and an iso-height consistency arrangement of particles. Only a small amount of trimming or no trimming is required in the later stage, so the diamonds are basically wear-free; the regularly arranged diamonds are basically not blocked during grinding, and the grinding process is smooth, reducing noise, and improving the durability and precision of the roller; the diamonds electroplated on the negative mold cavity are coated with nickel, so that at high temperatures, the diamonds will not move and float, resulting in disordered arrangement, inconsistent height and other problems; the inert gas shielded induction brazing process achieves a strong chemical metallurgical bond between the metal brazing material and the diamond particles, reducing or avoiding oxidation of the diamond and the metal binder, and significantly improving the holding force of the metal binder on the diamond compared to simple inlay coating; the induction heating speed is fast and can achieve local heating, reducing the heat input to the substrate and causing little thermal damage to the substrate; heat treatment is performed during the cooling process to reduce or eliminate stress in the substrate, so that the workpiece substrate is restored to a state close to its original state, while saving energy. Summary of the Invention

[0014] This invention addresses the current problems in diamond roller manufacturing, such as disordered diamond particle arrangement, which can easily lead to debris clogging and accumulation during grinding, high grinding temperatures, thermal deformation, burns, and cracks on the workpiece; inconsistent diamond particle height, long post-processing time, and severe diamond wear. The invention proposes a manufacturing process for precision diamond rollers. This process achieves regular particle arrangement through a hole template method, combined with internal electroplating, resulting in a highly precise roller with minimal or no post-processing required. Induction brazing offers rapid heating and a high metallurgical bond strength. Consequently, rollers manufactured using this process exhibit high production efficiency, regular diamond arrangement, high surface precision and bond strength, wear resistance, and a long service life.

[0015] To achieve the above object, the present invention adopts the following technical solutions: A manufacturing process for a precision diamond roller, the process is as follows: (1) A female mold cavity and a hole template are made according to the shape of a diamond roller. The hole template is provided with a number of through holes that are consistent with the arrangement of diamond particles. The side of the hole template that contacts the female mold cavity is provided with a number of protrusions of the same height; (2) Diamond particles are dropped into the plating area in the cavity of the female mold through the through-hole of the hole template, and one end of the diamond particles is initially fixed in the cavity of the female mold by electroplating the metal coating; (3) Dip the CVD strip into the brazing coating material and insert it into the gap of the outer circle of the roller base. Apply a certain thickness of brazing coating material on the working area of the roller and scrape it flat to obtain the brazing coating; (4) Assembling the negative mold cavity of step (2) and the roller of step (3) so that the other end of the diamond particle is buried in the brazing coating material, fixed, and dried; (5) In a protective atmosphere, heat and braze the working area of the roller. When the brazing coating material on the surface of the roller base melts, mechanical vibration is applied to the roller. When the heating is stopped, the vibration is stopped at the same time. (6) After step (5), the negative mold cavity of the roller is removed to expose the diamond particles on the surface, thereby obtaining a diamond roller blank, which is then precisely trimmed until it meets the requirements of the finished product.

[0016] Furthermore, 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 ±0.005 mm; the thickness of the hole template is 3 to 8 mm; the height of the protrusion on the hole template is 30% to 50% of the particle size of the diamond particles, and the particle size of the diamond is less than the diameter of the through hole on the hole template and less than twice the diamond particle size.

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

[0018] Furthermore, in step (3), the solder coating material is obtained by mixing a solder and a binder, wherein the solder accounts for 90-95 wt% and the binder accounts for 5-10 wt% of the solder coating material.

[0019] Furthermore, the brazing filler metal is a chromium-containing nickel-based filler metal or a Cu-Sn-Ti filler metal, with a filler metal particle size of 200-300 mesh and a melting temperature range of 900-1050°C. The chromium-containing nickel-based filler metal is preferably BNi82CrSiFeB (BNi-2) or BNi76Cr14P10 (BNi-7); the Cu-Sn-Ti filler metal is preferably a Cu-15Sn-10Ti or Cu-10Sn-5Ti alloy.

[0020] Furthermore, in step (3), the side clearance of the CVD strip in the groove around the roller is 0.03-0.1 mm; and the thickness of the brazing coating is 25-40% of the diamond particle size.

[0021] Furthermore, in step (4), the drying temperature is 80-95°C, and the drying time is 30-120 minutes.

[0022] Furthermore, in step (5), the heating temperature is 950-1100°C, the heating time is 5-8s, the vibration frequency is 15-25Hz, and the amplitude is 0.5-2mm; after stopping the heating, when the roller is cooled to 650-850°C, the roller is quenched and then tempered at 200-300°C for 30-90 min.

[0023] Specifically, the present invention comprises the following steps: (1) Mold design and processing: A female mold cavity is made according to the shape of the diamond roller, and then a hole template with the same shape as the female mold cavity is made. The surface of the hole template that contacts the female mold cavity is provided with a number of through holes that are consistent with the arrangement of diamond particles and a number of protrusions with the same height; (2) Internal electroplating: Before electroplating, the diamond and the negative mold cavity are treated with degreasing, impurity removal, and pickling activation. The unplated area of the negative mold cavity is insulated and protected. A hole template is placed and the two are fixed. Diamond particles are filled into the through holes of the hole template. The diamond particles fall into the plated area of the negative mold cavity through the through holes. Then, a nickel layer is plated on the plated area of the negative mold cavity by electrochemical deposition to fix the diamond particles in the negative mold cavity. (3) Pretreatment: Clean and remove oil and impurities from the finished roller, protect the roller working area, and then apply a layer of high-temperature refractory mud around its inner ring to prevent turbulence of the brazing material during high-temperature heating; (4) Preparation of brazing coating materials: After designing the ratio of brazing material and binder, weigh each component according to the proportion, and then use mechanical stirring to mix and set aside; Wherein, by mass percentage, the solder accounts for 90-95%, and the binder accounts for 5-10%; The brazing filler metal is nickel-based or copper-based, with a particle size of 200-300 mesh and a melting temperature range of 900-1050° C. The binder is a polymer solvent, for example, the binder model: Handy Flo 660, manufactured by Lukos Brazing Materials (Suzhou) Co., Ltd. (5) CVD strip inlay and brazing coating material coating: The laser-cut CVD strip is dipped in brazing coating material by artificial implantation and inserted into the gap of the roller base tip (outer circle). Then, a certain thickness of brazing coating material is applied to the roller working area and a polytetrafluoroethylene scraper is used to scrape and smooth it. (6) Assembling and fixing the female mold cavity and the roller base: Assemble the female mold cavity coated with diamonds and the roller coated with brazing coating material, so that the diamonds are buried in the brazing coating material, and fix them with a fixture after adjusting the distance; (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 roller working area. The maximum temperature of the roller surface is 950~1100℃, and the holding time is 5~8s. During this period, when the brazing coating material on the roller substrate melts, mechanical vibration is applied to the roller. When the heating is stopped, the vibration is stopped at the same time. At the same time, the brazing of the CVD strip and the roller substrate, and the brazing of the diamond particles and the roller substrate is completed. When the temperature is 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 liquid is quenching oil; (9) Precision finishing: After heat treatment, the roller is turned to remove the negative mold cavity material so that the diamond particles are exposed on the surface to obtain the diamond roller blank. Then, the deviation value is preliminarily measured by instruments such as Zeiss three-coordinate measuring instruments, Taylor measuring instruments, and Wangong display instruments, and the appropriate finishing allowance is calculated. On a special finishing machine, it is repeatedly ground many times until it meets the requirements of the finished product; The dimensional accuracy of the diamond roller blank and the theoretical deviation value of the finished diamond roller are about 0.003~0.015mm; (10) Inspection and packaging: The precision-trimmed diamond rollers are strictly inspected. The qualified finished diamond rollers are sprayed with anti-rust oil on the surface, wrapped with protective film, sealed and put into storage.

[0024] The present invention has the following beneficial effects: 1) A hole template is added during the internal electroplating process to achieve regular and orderly arrangement of diamonds. There is basically no clogging during grinding, and the grinding process is smooth, which improves the durability and precision of the roller.

[0025] 2) The diamond roller blank manufactured by the internal electroplating method has high dimensional accuracy, no principle error caused by different diamond particle sizes or different fixed heights, consistent height, and higher surface accuracy; this method is simple and efficient, with low production cost, and requires no subsequent processing or only a small amount of fine-tuning.

[0026] 3) After electroplating, the diamond is coated with nickel. The melting point of nickel is 1453℃ and the maximum heating temperature is 1100℃. Therefore, the problem of nickel melting causing the diamond to move and float will not occur. The diamond can maintain an orderly arrangement and high consistency.

[0027] 4) Brazing materials include BNi82CrSiFeB (BNi-2) or BNi76Cr14P10 (BNi-7) alloy, Cu-15Sn-10Ti or Cu-10Sn-5Ti alloy, etc. The elements such as Cr or Ti in these brazing materials 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 local heating with little heat input to the substrate.

[0029] 6) After roller brazing is completed, quenching heat treatment is completed 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a flow chart of the manufacturing process of the present invention; Figure 2 is a schematic diagram of a roller base; Figure 3 Schematic diagram of the structure of the hole template; Figure 4 Schematic diagram of the assembly of the female mold cavity (colored green) and the hole template (colored blue); Figure 5 Schematic diagram of the roller substrate after being inlaid with CVD strips, coated with brazing material (colored in yellow) and high-temperature refractory mud (colored in red); Figure 6 Schematic diagram of the assembly of the female mold cavity and the roller base. DETAILED DESCRIPTION

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments: Example 1 A manufacturing process for a precision diamond roller, such as Figure 1 As shown, the process is as follows: A: According to the designed outer dimensions of the roller base (the outer dimensions of the roller base are as follows Figure 2 As shown) Precision machined stainless steel metal female mold cavity (hereinafter referred to as the female mold cavity, the shape is as shown) Figure 4 As shown) and a polytetrafluoroethylene plate hole template, the negative mold cavity accuracy is ± 0.005mm, and then it is degreased, impurities and oxide layer treated, and the unplated area is sealed and protected with insulating paper; through holes are processed on the polytetrafluoroethylene plate according to the size and arrangement of diamonds (the structural diagram of the hole template is shown in Figure 3 As shown in the figure), the diamond particle size is 850~950μm, the through hole diameter in the hole template is 1000μm, and the thickness of the hole template is 3mm.

[0032] There are evenly distributed protrusions on the contact side of the hole template and the female mold cavity to control the distance between the two, and the protrusion height is 400μm.

[0033] B: The negative mold cavity (5wt% H2SO4 etched at room temperature for 2-3 minutes) and diamond particles (PdCl2 concentration of 0.2-0.5 g / L, commercial concentrated HCl added at 10 mL / L mixed solution, for 10 minutes at room temperature) for pickling activation, the hole template and the negative mold cavity are fixed with a fixture and placed in the electroplating solution, and then diamonds are sprinkled into the through holes of the hole template, spread and pressed to fill to ensure that there are diamonds in each through hole and in contact with the negative mold cavity, and nickel is plated in the negative mold cavity by electrochemical deposition. Specifically, the formula of paragraph 71 of the specification of patent ZL201510608273.9 can be used, that is, the electroplating solution used for electroplating contains the following components in the following concentrations: 320g / L nickel sulfamate, 30g / L nickel chloride, 40g / L boric acid, 0.04g / L sodium dodecyl sulfate, and 0.5g / L 1,4-butynediol; the pH value of the electroplating solution is 4.2, the temperature is 40°C, and the current density is 1.5A·dm -2 After electroplating, the diamond is coated with a coating thickness of 35 μm. After plating, it is cleaned with clean water and blown dry for later use.

[0034] C: Clean the roller base after finishing to remove oil and impurities, then cover the roller working area with plastic wrap, such as Figure 5 As shown, apply a layer of high-temperature refractory mud (model AL-70M, manufacturer: Jiashan Yourui Refractory Material Co., Ltd.) around the inner ring to prevent turbulence of the brazing material when brazing is heated to high temperature; D: According to the mass fraction, 95% Ni-based solder and 5% binder are mixed evenly in a blender and set aside; The Ni brazing filler metal is BNi82CrSiFeB (BNi-2) with a melting point of 1020-1050° C. and a particle size of 200-250 mesh. The binder is purchased from Lukos Brazing Materials (Suzhou) Co., Ltd., model: Handy Flo 660.

[0035] E: artificial implantation, such as Figure 5 As shown, the 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 material is coated on the upper and lower surfaces of the roller substrate and smoothed using a polytetrafluoroethylene scraper with a thickness of 300 μm.

[0036] F: If Figure 6 As shown, a fixture is used to adjust the distance between the female mold cavity and the working area surface of the roller base so that they are parallel to each other and then fixed. The diamond particles in the female mold cavity are embedded in the nickel-based brazing coating material.

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

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

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

[0040] I: After heat treatment, the roller is turned to remove the stainless steel negative mold cavity material. The Zeiss three-coordinate measurement shows that the deviation between the dimensional accuracy of the diamond roller blank and the finished diamond roller is about 0.010mm. Then, it is repeatedly ground on a special finishing machine until it meets the finished product requirements.

[0041] G: Inspection and packaging: The diamond rollers that have been ground are strictly inspected. The qualified diamond rollers are sprayed with anti-rust oil on the surface, wrapped with protective film, sealed and put into storage.

[0042] Example 2 A manufacturing process for a precision diamond roller, such as Figure 1 As shown, the process is as follows: A: According to the designed outer dimensions of the roller base (the outer dimensions of the roller base are as follows Figure 2 As shown) Precision machined stainless steel metal female mold cavity (hereinafter referred to as the female mold cavity, the shape is as shown) Figure 4 As shown) and a polytetrafluoroethylene plate hole template, the negative mold cavity accuracy is ± 0.005mm, and then it is degreased, impurities and oxide layer treated, and the unplated area is sealed and protected with insulating paper; through holes are processed on the polytetrafluoroethylene plate according to the size and arrangement of diamonds (the structural diagram of the hole template is shown in Figure 3 As shown in the figure), the diamond particle size is 850~950μm, the through hole diameter in the hole template is 1000μm, and the thickness of the hole template is 3mm.

[0043] There are evenly distributed protrusions on the contact side of the hole template and the female mold cavity to control the distance between the two, and the protrusion height is 400μm.

[0044] B: Acid pickling and activation are performed on the negative mold cavity (5wt% H2SO4 etching at room temperature for 2-3 minutes) and the diamond particles (in a mixed solution of 0.2-0.5 g / L PdCl2 and 10 mL / L commercial concentrated HCl, for 10 minutes at room temperature). The hole template and the negative mold cavity are fixed with a fixture and placed in the electroplating solution. The diamonds are then sprinkled into the through holes of the hole template, spread and pressed to ensure that there are diamonds in each through hole and in contact with the negative mold cavity. Nickel is plated in the cavity by electrochemical deposition. Specifically, the formula in paragraph 71 of the patent ZL201510608273.9 specification can be used. The nickel layer continues to grow and covers the diamond. The coating thickness is 35μm. After plating, it is rinsed with clean water and blown dry for later use.

[0045] C: Clean and remove oil and impurities from the finished roller base, then wrap the roller working area with plastic wrap and apply a layer of high-temperature refractory mud (model AL-70M, manufacturer: Jiashan Yourui Refractory Material Co., Ltd.) around its inner ring to prevent turbulence of the brazing material during high-temperature brazing. D: Calculate by mass fraction by mixing 95% Cu-Sn-Ti solder and 5% binder in a blender 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°C 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 the artificial implantation method, the laser-cut CVD strip is dipped in Cu-10Sn-5Ti brazing coating material and inserted into the gap of the outer ring of the roller substrate. Then a layer of Cu-10Sn-5Ti brazing filler metal is coated on the upper and lower surfaces of the roller substrate. A polytetrafluoroethylene scraper is used to scrape the surface smooth to a thickness of 300μm.

[0047] F: Use a fixture to adjust the distance between the female mold cavity and the working area of the roller base so that they are parallel to each other and then fix them. The diamond particles in the female mold cavity are buried in the Cu-10Sn-5Ti brazing coating material.

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

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

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

[0051] I: After heat treatment, the roller is turned to remove the stainless steel negative mold cavity material. The Zeiss three-coordinate measurement shows that the deviation between the dimensional accuracy of the diamond roller blank and the finished diamond roller is about 0.010mm. Then, it is repeatedly ground on a special finishing machine until it meets the finished product requirements.

[0052] G: Inspection and packaging: The diamond rollers that have been ground are strictly inspected. The qualified diamond rollers are sprayed with anti-rust oil on the surface, wrapped with protective film, sealed and put into storage.

[0053] Example 3 A manufacturing process for a precision diamond roller, such as Figure 1 As shown, the process is as follows: A: According to the designed outer dimensions of the roller base (the outer dimensions of the roller base are as follows Figure 2 As shown) Precision machined stainless steel metal female mold cavity (hereinafter referred to as the female mold cavity, the shape is as shown) Figure 4 As shown) and a polytetrafluoroethylene plate hole template, the negative mold cavity accuracy is ± 0.005mm, and then it is degreased, impurities and oxide layer treated, and the unplated area is sealed and protected with insulating paper; through holes are processed on the polytetrafluoroethylene plate according to the size and arrangement of diamonds (the structural diagram of the hole template is shown in Figure 3 As shown in the figure), the diamond particle size is 300~355μm, the through hole diameter in the hole template is 400μm, and the thickness of the hole template is 3mm.

[0054] There are evenly distributed protrusions on the side of the hole template that contacts the female mold cavity in order to control the distance between the two. The height of the protrusions is 150μm.

[0055] B: The negative mold cavity (5wt% H2SO4 etched at room temperature for 2-3 minutes) and the diamond particles (in a mixed solution of PdCl2 concentration of 0.2-0.5 g / L and commercial concentrated HCl added at 10 mL / L, for 10 minutes at room temperature) are pickled and activated. The hole template and the negative mold cavity are fixed with a fixture and placed in the electroplating solution. The diamonds are then sprinkled into the through holes of the hole template, spread and pressed to ensure that there are diamonds in each through hole and in contact with the negative mold cavity. Nickel is plated in the negative mold cavity by electrochemical deposition. Specifically, the formula in paragraph 71 of the patent ZL201510608273.9 can be used. The nickel layer continues to grow and covers the diamond. The coating thickness is 15μm. After plating, it is rinsed with clean water and blown dry for later use.

[0056] C: Clean and remove oil and impurities from the finished roller base, 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 Material Co., Ltd.) around its inner ring to prevent turbulence of the brazing material during high-temperature brazing. D: Calculate by mass fraction by mixing 95% Cu-Sn-Ti solder and 5% binder in a blender and set aside; The Cu-Sn-Ti solder is Cu-10Sn-5Ti, has a melting point of 900° C. to 930° C., and a particle size of -300 mesh.

[0057] E: Using the artificial implantation method, the laser-cut CVD strip is dipped in Cu-10Sn-5Ti brazing coating material and inserted into the gap of the outer ring of the roller substrate. Then a layer of Cu-10Sn-5Ti brazing filler metal is coated on the upper and lower surfaces of the roller substrate. A polytetrafluoroethylene scraper is used to scrape the surface smooth to a thickness of 300μm.

[0058] F: Use a fixture to adjust the distance between the female mold cavity and the working area of the roller base so that they are parallel to each other and then fix them. The diamond particles in the female mold cavity are buried in the Cu-10Sn-5Ti brazing coating material.

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

[0060] H: In an argon atmosphere, the roller substrate to be welded is heated in the argon atmosphere using a high-frequency induction welding machine equipped with a contoured coil (the coil shape is consistent with the roller shape) to heat the roller working area. The maximum surface temperature of the roller is 950°C, and the holding time is 6 seconds. When cooled to 720°C, quenching is performed using quenching oil, and tempering is performed at 260°C with a tempering holding time of 30 minutes.

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

[0062] I: After heat treatment, the roller is turned to remove the stainless steel negative mold cavity material. The Zeiss three-coordinate measurement shows that the deviation between the dimensional accuracy of the diamond roller blank and the finished diamond roller is about 0.010mm. Then, it is repeatedly ground on a special finishing machine until it meets the finished product requirements.

[0063] G: Inspection and packaging: The diamond rollers that have been ground are strictly inspected. The qualified diamond rollers are sprayed with anti-rust oil on the surface, wrapped with protective film, sealed and put into storage.

[0064] Comparative Examples 1 to 3: A single-layer diamond grinding wheel was prepared by vacuum brazing using the same alloy brazing material and diamond raw material as in Examples 1, 2, and 3. The vacuum brazing process parameters were referenced to 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 of composite electroplating / induction brazing and vacuum brazing diamond rollers Note: The life of the roller in each embodiment is calculated based on the life of the roller in the corresponding comparative example. For example, the life of the roller in embodiment 1 is 1.18 times that of the roller in comparative example 1.

[0066] As can be seen from Table 1, the diamond roller produced by the present application has a low degree of diamond wear and a short dressing time. Under the same conditions, the life of the alumina ceramic grinding wheel is longer than that of the diamond roller produced by vacuum brazing in Example 1. This is because the diamond particle sizes of the same size in the national standard are not completely consistent. For example, the particle size range of particle size 18 / 20 is 850~1000μm, and the maximum difference in particle size can be up to 150μm, which has a great impact on the accuracy of the roller. During the brazing process, some diamond abrasives float up due to the melting of the alloy brazing material, and have no direct contact with the substrate. The above problems make the tops of the diamond abrasives of the vacuum brazed diamond roller not at the same height, thereby reducing the accuracy. In order to improve the accuracy of the vacuum brazed roller, it needs to be precisely ground and dressed after brazing. Diamond abrasive grains are crushed and removed, and the diamonds are subjected to impact and wear during the dressing process, resulting in excessive wear. Dressing can also reduce the sharpness of the diamonds, which seriously affects the performance and life of the tool. Irregularly arranged diamond abrasive grains can easily cause grinding chips to accumulate between the abrasive grains during the grinding process, reducing the grinding efficiency. The high temperature generated during the grinding process can cause thermal deformation, burns, and cracks on the workpiece. Regularly arranged diamonds rarely clog during grinding, and the grinding process is smooth, reducing noise and improving the durability and precision of the roller.

Claims

1. A manufacturing process for a precision diamond roller, characterized in that: The process is as follows: (1) A female mold cavity and a hole template are made according to the shape of a diamond roller. The hole template is provided with a number of through holes that are consistent with the arrangement of diamond particles. The side of the hole template that contacts the female mold cavity is provided with a number of protrusions of the same height; (2) Diamond particles are dropped into the plating area in the cavity of the female mold through the through-hole of the hole template, and one end of the diamond particles is initially fixed in the cavity of the female mold by electroplating the metal coating; (3) Dip the CVD strip into the brazing coating material and insert it into the gap of the outer circle of the roller base. Apply a certain thickness of brazing coating material on the working area of the roller and scrape it flat to obtain the brazing coating; (4) Assembling the negative mold cavity of step (2) and the roller of step (3) so that the other end of the diamond particle is buried in the brazing coating material, fixed, and dried; (5) In a protective atmosphere, heat and braze the working area of the roller. When the brazing coating material on the surface of the roller base melts, mechanical vibration is applied to the roller. When the heating is stopped, the vibration is stopped at the same time. (6) After step (5), the negative mold cavity of the roller is removed to expose the diamond particles on the surface, thereby obtaining a diamond roller blank, which is then precisely trimmed 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 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 particle size of the diamond particles, and the particle size of the diamond is less than 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 212-1000 μm; 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 solder coating material is obtained by mixing a solder and a binder, wherein the solder accounts for 90-95 wt% and the binder accounts for 5-10 wt% of the solder coating material.

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, the solder particle size is 200~300 mesh, and the melting temperature range of the solder is 900~1050℃.

6. The manufacturing process of the precision diamond roller according to claim 1, characterized in that: In step (3), the side clearance of the CVD strip in the groove around the roller is 0.03-0.1 mm; the thickness of the brazing coating 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°C and the drying time is 30-120 min.

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 stopping the heating, when the roller cools to 650~850℃, the roller is quenched and then tempered at 200~300℃ for 30~90 min.

Images