CN111376007A - Welded pseudo-ball-end diamond micro-milling cutter, micro-milling blade and manufacturing process - Google Patents
Welded pseudo-ball-end diamond micro-milling cutter, micro-milling blade and manufacturing process Download PDFInfo
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- CN111376007A CN111376007A CN202010381057.6A CN202010381057A CN111376007A CN 111376007 A CN111376007 A CN 111376007A CN 202010381057 A CN202010381057 A CN 202010381057A CN 111376007 A CN111376007 A CN 111376007A
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- cutter
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- milling
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
- B23P15/28—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass cutting tools
- B23P15/34—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass cutting tools milling cutters
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23C—MILLING
- B23C5/00—Milling-cutters
- B23C5/02—Milling-cutters characterised by the shape of the cutter
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/0008—Soldering, e.g. brazing, or unsoldering specially adapted for particular articles or work
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
Abstract
The invention belongs to the technical field of cutter manufacturing, and particularly relates to a welded pseudo-ball-head diamond micro-milling cutter, a micro-milling blade and a manufacturing process. The manufacturing process of the welded pseudo-ball-head diamond micro-milling cutter comprises the following steps: preparing a blade blank; preparing a knife handle; brazing the blade blank on the head of the cutter handle to manufacture a cutter blank; and grinding the blade blank to obtain the formed cutter. The problem of interference between the tool shank and the grinding disc caused by extremely narrow operable space of the front tool face can be effectively solved.
Description
Technical Field
The invention belongs to the technical field of cutter manufacturing, and particularly relates to a welded pseudo-ball-head diamond micro-milling cutter, a micro-milling blade and a manufacturing process.
Background
In recent years, the development of traditional metal processing technology has become mature, and the application of high-precision miniature devices and structures in the fields of microelectronic industry, biomedical equipment, electronic communication, precise instruments, aerospace and the like opens up a new research direction. The micro-milling mode overcomes the limitations of chemical corrosion or photolithography, and can be more and more widely applied in the foreseeable future. Because the size of the parts is tiny and the precision requirement is higher, the traditional processing method must be modified and innovated, and the modification causes that new processing technology and equipment must be adopted in the mechanical manufacturing industry, and the processing precision is improved to meet the high precision requirement of tiny parts.
The quality of the micro milling cutter is one of important factors influencing the surface quality and the processing efficiency of a micro milling workpiece. At present, the materials of the micro milling cutter which is generally applied commercially are hard alloy, ceramic and diamond. Among them, single crystal diamond material itself has many excellent physicochemical properties including extremely high hardness, wear resistance, thermal conductivity, and the like. The natural single crystal diamond becomes an indispensable cutter material for micro milling due to a plurality of advantages, and the natural single crystal diamond has remarkable advantages particularly in the processing of various optical reflectors and lenses, microstructures and micro lens arrays, Fresnel lenses and complex micro parts required by national defense advanced technology and civil high-tech products.
The mechanical sharpening method has high processing efficiency, can stably sharpen a high-precision sharp cutting edge, and becomes a main method for processing the single crystal diamond cutter. However, for the welded diamond micro milling cutter, the milling blade cannot be taken down again after being clamped on the cutter handle, so that the space for sharpening the front cutter face is extremely narrow during sharpening, and the end part of the cutter handle interferes with the grinding disc, so that the edge forming sharpening of the diamond micro milling cutter is difficult to finish by adopting the existing mechanical sharpening method.
Disclosure of Invention
The invention provides a welded pseudo-ball head diamond micro milling cutter, a micro milling blade and a manufacturing process.
In order to solve the technical problem, the invention provides a manufacturing process of a welded type false ball head diamond micro-milling cutter, which comprises the following steps: preparing a blade blank; preparing a knife handle; brazing the blade blank on the head of the cutter handle to manufacture a cutter blank; and grinding the blade blank to obtain the formed cutter.
In a second aspect, the present invention further provides a process for manufacturing a micro milling insert, comprising: preparing a blade blank; and grinding the blade blank.
In a third aspect, the present invention also provides a micro milling insert, comprising: the blade comprises a blade body and an arc cutting edge positioned on the blade body.
In a fourth aspect, the present invention further provides a welded type pseudo-ball head diamond micro milling cutter, including: the micro-milling cutter comprises a cutter handle and a micro-milling blade brazed at the head of the cutter handle.
The welded pseudo-ball-end diamond micro milling cutter, the micro milling blade and the manufacturing process have the advantages that the existing mechanical sharpening process technology is changed, the cutting edge forming coarse grinding, the interference edge antifriction and the cutting edge fine grinding of the pseudo-ball-end diamond micro milling cutter can be efficiently completed, the problem of interference between a cutter handle and a grinding disc caused by extremely narrow operable space of a front cutter face can be effectively solved, the surface roughness of a rear cutter face of the pseudo-ball-end diamond micro milling cutter can reach below Ra 2nm, the arc waviness of the cutting edge can be better than 50 nm/90-degree arc wrap angle, the blunt radius of the cutting edge is below 30nm, and the micro-collapse defect of the cutting edge cannot be observed under the magnification of an optical microscope 1250 ×.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
FIG. 1 is a flow chart of a manufacturing process of a welded type pseudo-ball head diamond micro-milling cutter;
FIG. 2 is a schematic view of the construction of a planetary type grinder;
FIG. 3 is a schematic view of the radiused edge of a rough grinding blade blank;
FIG. 4 is a schematic view of the interference site on the right side of the antifriction cutting edge;
in the figure: the grinding machine comprises a clamp 1, a cutter blank 2, a cutter handle 21, a micro-milling blade 22, a planetary grinding machine 3, a main shaft 31 and a grinding wheel disk 32.
Detailed Description
To make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is apparent that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
The method aims at solving the problems that in the mechanical sharpening process of the prior mechanical sharpening method for forming the edge on the front knife face, the protruding part of the front knife face is narrow, the operable space is small, and the knife handle is easy to interfere with a grinding disc. Referring to fig. 1, this embodiment 1 provides a manufacturing process of a welded type pseudo-ball head diamond micro-milling cutter, including: preparing a blade blank; preparing a knife handle; brazing the blade blank on the head of the cutter handle to manufacture a cutter blank; and grinding the blade blank to obtain a formed cutter, namely the welded type pseudo-ball-end diamond micro-milling cutter.
Optionally, the preparing the blade blank comprises: cutting the diamond particles into a blade body; the lower bottom surface and the upper plane of the blade body are ground into planes. Alternatively, the blade body has a thickness of 0.5mm and the upper plane of the blade body serving as the rake face requires a very low roughness surface to be ground on a flat grinder.
Optionally, the preparation tool shank includes: the taper angle of the cutter handle is milled in a rolling way to form the head part of the cutter handle; and cutting a mounting seam at the head of the knife handle. Specifically, a slit, that is, the mounting slit, may be cut into the head of the cemented carbide tool holder with the tapered angle milled by using a linear cutting technique. Optionally, as shown in fig. 3, the tool holder 21 is made of hard alloy, the diameter of the tool holder is 6mm, the length of the tool holder is 50mm, and the width of the slit at the head of the tool holder is 0.5 mm.
Optionally, the step of manufacturing the cutter blank comprises the steps of clamping the blade blank in the mounting seam, wrapping the blade blank at the front clamping position and the rear clamping position of the blade blank by using brazing filler metal, keeping the cutter handle in an upright state, conducting vacuum brazing treatment in a vacuum heat treatment furnace, keeping the temperature after brazing, keeping the vacuum degree in the vacuum heat treatment furnace and naturally cooling, specifically, clamping the blade blank in a slit at the head of the cutter handle and adjusting the position of the blade blank, wrapping the front blade and the rear blade by using silver-copper-titanium brazing filler metal, keeping the cutter handle in an upright state, placing the processed blade blank and the cutter handle on an object stage of the vacuum heat treatment furnace, conducting vacuum brazing treatment, keeping the blade blank and the cutter handle for a period of time after the temperature is reached, keeping the vacuum degree in the furnace and naturally cooling, and achieving stable connection of the diamond milling blade and the hard alloy cutter handle-3Pa, the brazing temperature is 830-910 ℃, and the heat preservation time is 15-20 min.
Optionally, referring to fig. 2-4, the grinding the insert blank comprises: placing a cutter blank 2 on a planetary grinding machine 3 in a constant temperature environment through a clamp 1, keeping a pitch angle of a main shaft of the planetary grinding machine to be 3-5 degrees larger than a blade back angle of a forming cutter, and roughly grinding an arc cutting edge of the blade blank; adjusting the pitch angle of a main shaft of the planetary grinding machine to be 0 degree, deflecting the clamp to the right by 45 degrees, and reducing the interference part on the right side of the arc cutting edge to form a 45-degree abrasion reducing surface; and adjusting the pitch angle of the main shaft of the planetary grinding machine to the rear angle value of the blade of the forming cutter, and finely grinding the blade blank. Wherein the temperature of the constant temperature environment is 20 +/-0.5 ℃. Specifically, referring to fig. 2, the planetary grinding machine 3 is placed in a constant temperature environment, the temperature is 20 ℃, the temperature precision is ± 0.5 ℃, the supply air pressure is stable, the pitch angle of the main shaft 31 is set to 10 ° (as long as the pitch angle is 3-5 ° greater than the back angle of the forming tool), the grinding machine is started to run for 30min without load, so as to reach a stable state; referring to fig. 3, the brazed cutter blank is clamped on a clamp 1, and rough grinding forming of the circular arc cutting edge 21 of the blade blank 2 is completed through a grinding wheel disk 32 of a planetary grinding machine 3 according to the geometric parameters of the formed cutter; returning the pitch angle of the main shaft to 0 degrees, deflecting the clamp to the right by 45 degrees, and finishing the antifriction of the interference part of the right blade to form a 45-degree antifriction surface; the pitch angle of the main shaft 31 of the planetary grinder 3 is set to a relief angle value required for forming the cutter, and the blade blank 2 is finely ground and formed.
Optionally, the process parameters of rough grinding the arc cutting edge of the blade blank specifically are as follows: the planetary grinding machine adopts a 800# bronze base diamond grinding wheel, the cutter handle does not rotate, the grinding pressure is 24.5N, the rotating speed of a main shaft is 4200rpm, the single feed amount is 5 mu m, the swing speed of a swing shaft is 6 DEG/s, and the grinding wheel disk does not reciprocate.
Optionally, the process parameters of the interference part on the right side of the antifriction arc-shaped cutting edge are specifically as follows: the planetary grinding machine adopts a 800# bronze base diamond grinding wheel, the cutter handle does not rotate, the grinding pressure is 24.5N, the rotating speed of a main shaft is 4200rpm, the single feed amount is 2 mu m, the grinding wheel does not move with a swing shaft, and the grinding wheel disc additionally moves in a reciprocating way with the stroke of 1-3 mm.
Optionally, the fine grinding forming process parameters specifically include: the planetary grinding machine adopts a 3000# bronze-based diamond grinding wheel, the tool shank does not rotate, the grinding pressure is 24.5N, the rotating speed of the main shaft is 2400rpm, the single feed amount is less than 1 mu m, the swing speed of the swing shaft is 6 degrees/s, and the grinding wheel disk does not have additional reciprocating motion.
Optionally, the manufacturing process of the welded type pseudo-ball diamond micro-milling cutter further comprises: cleaning a cutter, namely detaching the ground forming cutter from the clamp, dipping the acetone by using a cotton wool stick, and wiping pollutants along the milling cutter head and the cutting edge; and detecting whether the edge micro-collapse defect and the edge waviness are qualified or not, if not, returning to the corresponding process step, and re-grinding the edge until the manufacture of the pseudo-ball-end diamond micro-milling cutter is completed.
Example 2
On the basis of embodiment 1, this embodiment 2 provides a manufacturing process of a micro milling insert, including: preparing a blade blank; and grinding the blade blank.
Wherein grinding the insert blank comprises: placing the cutter blank on a planetary grinding machine in a constant temperature environment through a clamp, keeping the pitch angle of a main shaft of the planetary grinding machine to be 3-5 degrees larger than the blade back angle of a forming cutter, and roughly grinding the arc cutting edge of the blade blank; adjusting the pitch angle of a main shaft of the planetary grinding machine to be 0 degree, deflecting the clamp to the right by 45 degrees, and reducing the interference part on the right side of the arc cutting edge to form a 45-degree abrasion reducing surface; and adjusting the pitch angle of the main shaft of the planetary grinding machine to the rear angle value of the blade of the forming cutter, and finely grinding the blade blank.
Example 3
On any basis of embodiments 1-2, this embodiment 3 provides a micro-milling insert comprising: the blade body, be located the circular arc blade on the blade body. The interference part on the right side of the arc cutting edge is a 45-degree abrasion reducing surface, the arc waviness of the cutting edge is superior to a 50 nm/90-degree arc wrap angle, and the surface roughness of a rear cutter face of the arc cutting edge is less than Ra 2 nm.
Example 4
On the basis of any one of embodiments 1 to 3, fig. 3 and 4 provide a welded type pseudo-ball diamond micro-milling cutter, which comprises: a shank 21 and a micro-milling insert 22 brazed to the head of the shank 21 as previously described.
In conclusion, the welded pseudo ball-end diamond micro milling cutter, the micro milling blade and the manufacturing process of the invention can finish the coarse edge forming grinding, the interference edge reduction grinding and the fine edge grinding of the pseudo ball-end diamond micro milling cutter step by changing the existing mechanical sharpening process technology, not only can effectively solve the problem of interference between a cutter handle and a grinding disc caused by extremely narrow operable space of a front cutter face, but also is convenient for detecting the micro-collapse defect of the pseudo ball-end diamond micro milling cutter and regrinding the edge, the surface roughness of the rear cutter face of the finally prepared pseudo ball-end diamond micro milling cutter can reach below Ra 2nm, the circular waviness of the edge can be better than 50nm/90 degrees of circular wrap angle, the obtuse circular radius of the cutting edge is below 30nm, and the edge can not observe the micro-collapse defect under the magnification of an optical microscope 1250 ×.
In light of the foregoing description of the preferred embodiment of the present invention, many modifications and variations will be apparent to those skilled in the art without departing from the spirit and scope of the invention. The technical scope of the present invention is not limited to the content of the specification, and must be determined according to the scope of the claims.
Claims (10)
1. A manufacturing process of a welded pseudo-ball-head diamond micro-milling cutter is characterized by comprising the following steps:
preparing a blade blank;
preparing a knife handle;
brazing the blade blank on the head of the cutter handle to manufacture a cutter blank; and
and grinding the blade blank to obtain the formed cutter.
2. The manufacturing process according to claim 1,
the preparing the blade blank comprises:
cutting the diamond particles into a blade body;
the lower bottom surface and the upper plane of the blade body are ground into planes.
3. The manufacturing process according to claim 1,
the preparation handle of a knife includes:
the taper angle of the cutter handle is milled in a rolling way to form the head part of the cutter handle;
and cutting a mounting seam at the head of the knife handle.
4. The manufacturing process according to claim 3,
the forming of the cutter blank comprises:
clamping the blade blank in the mounting slot;
wrapping the front clamping part and the rear clamping part of the blade blank by using brazing filler metal, and keeping the cutter handle in an upright state;
carrying out vacuum brazing treatment in a vacuum heat treatment furnace;
heat preservation is carried out after brazing;
keeping the vacuum degree in the vacuum heat treatment furnace, and naturally cooling.
5. The manufacturing process according to claim 1,
grinding the insert blank comprises:
placing the cutter blank on a planetary grinding machine in a constant temperature environment through a clamp, keeping the pitch angle of a main shaft of the planetary grinding machine to be 3-5 degrees larger than the blade back angle of a forming cutter, and roughly grinding the arc cutting edge of the blade blank;
adjusting the pitch angle of a main shaft of the planetary grinding machine to be 0 degree, deflecting the clamp to the right by 45 degrees, and reducing the interference part on the right side of the arc cutting edge to form a 45-degree abrasion reducing surface;
and adjusting the pitch angle of the main shaft of the planetary grinding machine to the rear angle value of the blade of the forming cutter, and finely grinding the blade blank.
6. The manufacturing process according to claim 5,
the temperature of the constant temperature environment is 20 +/-0.5 ℃.
7. A process for manufacturing a micro-milling insert, comprising:
preparing a blade blank;
and grinding the blade blank.
8. A micro-milling insert, comprising:
the blade body, be located the circular arc blade on the blade body.
9. The micro milling insert of claim 8,
the interference part on the right side of the arc cutting edge is a 45-degree friction reducing surface.
10. The utility model provides a little milling cutter of pseudo-bulb diamond of welding formula which characterized in that includes:
the micro-milling cutter comprises a cutter handle and a micro-milling blade brazed at the head of the cutter handle.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010381057.6A CN111376007A (en) | 2020-05-08 | 2020-05-08 | Welded pseudo-ball-end diamond micro-milling cutter, micro-milling blade and manufacturing process |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010381057.6A CN111376007A (en) | 2020-05-08 | 2020-05-08 | Welded pseudo-ball-end diamond micro-milling cutter, micro-milling blade and manufacturing process |
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| CN111376007A true CN111376007A (en) | 2020-07-07 |
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| CN202010381057.6A Pending CN111376007A (en) | 2020-05-08 | 2020-05-08 | Welded pseudo-ball-end diamond micro-milling cutter, micro-milling blade and manufacturing process |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112705742A (en) * | 2020-12-22 | 2021-04-27 | 卡孚精密科技(嘉兴)有限公司 | Alloy cutter and machining process thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104128783A (en) * | 2014-07-17 | 2014-11-05 | 哈尔滨工业大学 | Method for manufacturing single-blade diamond micro-milling cutter |
| US9643282B2 (en) * | 2014-10-17 | 2017-05-09 | Kennametal Inc. | Micro end mill and method of manufacturing same |
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2020
- 2020-05-08 CN CN202010381057.6A patent/CN111376007A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104128783A (en) * | 2014-07-17 | 2014-11-05 | 哈尔滨工业大学 | Method for manufacturing single-blade diamond micro-milling cutter |
| US9643282B2 (en) * | 2014-10-17 | 2017-05-09 | Kennametal Inc. | Micro end mill and method of manufacturing same |
Non-Patent Citations (1)
| Title |
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| 杨辉编著: "《精密超精密加工技术新进展》", 31 August 2016, 航空工业出版社 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112705742A (en) * | 2020-12-22 | 2021-04-27 | 卡孚精密科技(嘉兴)有限公司 | Alloy cutter and machining process thereof |
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Application publication date: 20200707 |