JP4998778B2 - Nanocarbon fiber-containing electrodeposition tool and method for producing the same - Google Patents

Description

  The present invention relates to an electrodeposition tool containing nanocarbon fibers and a method for producing the same.

  It is known that a polishing tool in which nanocarbon fibers and abrasive grains are fixed with a binder is used for precision polishing of semiconductor wafers and interlayer insulating films.

  Abrasive tools disclosed in these known techniques include nanocarbon fibers having a diameter of 2 to 500 nm and an aspect ratio of 5 to 15000, cerium oxide, silicon oxide, aluminum oxide, titanium oxide, zirconium oxide, silicon carbide, tungsten carbide, Abrasive grains such as boron carbide, boron nitride, diamond and sapphire are bonded on a resin or metal substrate with a resin or metal binder.

  As the form of the tool, a grindstone, a polishing wheel, a grinding blade, a polishing pad and the like are described.

  As the workpiece, polycrystalline silicon, single crystal silicon, amorphous silicon, or the like is used for grinding or polishing silicon.

  As the base material of the tool, it is disclosed to use a resin such as plastic or rubber, a ceramic such as cement or glass, a pure metal or an alloy.

  Resinoid bonds, metal bonds, vitrified bonds, electrodeposition bonds, and the like are disclosed as binders.

In electric discharge machining, conductive diamond is used as an electrode tool, the conductive diamond electrode tool is connected to the positive electrode of the discharge power supply circuit, the workpiece is connected to the negative electrode, and the discharge pulse time is 3 to 30. It is also known that discharge machining is performed by setting any discharge pulse time in microseconds and setting the discharge current to any value of 1.5 to 15 A (Reference 3).
JP 2004-181484 A JP 2004-202681 A Susumu Arai, Morinobu Endo and Norio Kaneko; “Ni-deposited multi-walled carbon nanotubes by electrodeposition” Carbon, Volume 42, Issue 3, 2004, Pages 641-644 L. Shi, CF Sun, P. Gao, F. Zhou and WM Liu; “Electrodeposition and characterization of Ni-Co-carbon nanotubes composite coatings” Surface and Coatings Technology, In Press, Corrected Proof, Available online 20 June 2005, Japanese Laid-Open Patent Publication No. 2005-230938

  Recently, in the fields of semiconductors, optical communications, and biotechnology, there is a demand for an electrodeposition tool for machining fine holes and grooves having a diameter of 0.5 mm or less in hard and brittle materials such as quartz glass and ceramics and mold materials. Here, the “electrodeposition tool” refers to an electrodeposition grindstone and an electrode tool for electric discharge machining.

  However, in the electrodeposition tool in the above-mentioned known technique, since the nanocarbon fiber has conductivity, the composite plating film becomes very porous when an electrodeposition tool, particularly a tool with a small diameter is manufactured by electrolytic plating. In the case of electrodeposition tools for grinding, the porous composite plating film has a problem that the holding power of the abrasive grains is insufficient and the abrasive grains fall off early, and is particularly applicable to small-shaft grinding wheels with fine diameters. There is a problem that cannot be done. In the case of an electrodeposition tool for electric discharge machining, a porous composite plating film has a problem that heat conductivity is poor and low wear machining cannot be realized.

  In Documents 1 and 2, since it is a tool for surface polishing, there is a problem that the holding power of abrasive grains is weak for the above reason even if a tool with a small diameter is not assumed and applied.

  In the method for producing the nanocarbon fiber composite plating film of Document 3, the present invention is excellent because a pre-process of plating the nanocarbon fiber itself with nickel is performed and the number of processes is increased.

  In the method for producing the nanocarbon fiber composite plating film of Document 4, as the stirring method, electrolytic plating is performed while stirring the plating solution using a magnetic stirrer, but this method cannot form a dense composite plating film. Application to electrodeposition tools is difficult.

  Further, in the low-consumable electrode tool of Reference 5, since a very hard material called conductive diamond is used for the tool, machining of the tool shape is difficult, and a small-diameter cylindrical electrode tool having an outer diameter of 0.5 mm or less for generating electric discharge machining. In addition, there is a problem that it is difficult to manufacture an electrode tool having a fine shape with a pitch of several microns for electric discharge machining.

  Accordingly, the present invention has been made to solve the above-described problems, and has a dense composite plating film containing nanocarbon fibers, and has an ability to retain abrasive grains, discharge heat of processing, and surface lubricity. An electrodeposition tool with a small-diameter shaft for grinding that has excellent tool life and a fine electrode tool that has a dense composite plating film containing nanocarbon fibers and can realize low consumption electric discharge machining due to high thermal conductivity. It is an object of the present invention to provide a method for manufacturing these electrodeposition tools.

  The present invention has been made to solve the above-mentioned problems. The invention of claim 1 is a coating mainly composed of nickel having a deposition Vickers hardness of 150 to 300 by electrolytic plating, and a deposition Vickers hardness of 450 to 450 by electroless plating. At least one film selected from 800 nickel-based coatings or electrolytic plating-deposited Vickers hardness 40-200 copper-based coatings with a diameter of 10-100 nm and an aspect ratio (= long) The composite metal plating film having Vickers hardness 1.1 times to 2.5 times that of the plating film having the hardness which does not contain nanocarbon fibers and uniformly contains nanocarbon fibers having a thickness of 5 to 200) (Hereinafter referred to as “composite plating film”) is a nanocarbon fiber-containing electrodeposition tool disposed on at least the outermost surface of the metal plating film portion. Here, the “electrodeposition tool” is defined as an electrodeposition grindstone and an electrode tool for electric discharge machining. The “base material” is an object to be plated immediately before the step of forming the nanocarbon fiber composite metal plating film. In other words, materials such as cemented carbide (hereinafter referred to as “base metal”) that are constituent parts of the electrode tool, components in which abrasive grains are temporarily fixed to the base metal, electroforming molds that do not become constituent parts of the electrode tool, If it is in a state immediately before the step of forming the nanocarbon fiber composite metal plating film, it is defined as “base material”.

  According to a second aspect of the present invention, in the electrodeposition tool according to the first aspect, the composite plating film is formed on a cylindrical base material surface, and the plating film has a diameter of 1/5 to 1/200 of the grindstone diameter. A diameter containing hard abrasive grains and the nanocarbon fiber having a length equal to or less than the diameter of the abrasive grains, and fixing the hard abrasive grains to a base material with a part of the hard abrasive grains of the outermost surface layer exposed. It is an electrodeposition grindstone with a small diameter shaft of 0.01 mm to 3 mm.

  The invention according to claim 3 is an electrode tool for electric discharge machining among the electrodeposition tools according to claim 1. The electrode tool for electric discharge machining refers to an electrode tool for electric discharge machining for transferring an electrode shape to a workpiece, or an electrode tool for generating electric discharge machining in a columnar shape or a cylindrical shape used by scanning while rotating.

  The invention of claim 4 uses a plating bath in which 0.1 to 2 grams of nanocarbon fiber per liter is dispersed with a cationic surfactant, and in the process of forming a metal plating film mainly composed of nickel or copper, A nanocarbon fiber-containing electrode is formed by forming a nanocarbon fiber composite metal plating film on the surface of the base material by electrolytic plating or electroless plating in a state where the material is immersed in the plating bath and ultrasonic vibration is applied to the plating bath. It is a manufacturing method of a wearing tool.

  In the invention of claim 5, the nanocarbon fibers are dispersed in pure water or water to which a polar surfactant is added, the base material is immersed in the solution, and the nanocarbon fibers are fixed to the surface of the base material by electrophoresis. Then, in the process of forming the metal plating film mainly composed of nickel or copper, the base material is immersed in the plating bath, and the nanocarbon fiber composite metal plating film is formed by the electrolytic plating method or the electroless plating method. It is characterized by being a method for producing a nanocarbon fiber-containing electrodeposition tool characterized by being formed on the surface.

  Invention of Claim 6 is a base material in which the base material is a constituent part of the electrodeposition tool in the method for producing a nanocarbon fiber-containing electrodeposition tool according to Claims 4 and 5, and the nanocarbon fiber dispersion The metal plating film containing nanocarbon fibers and hard abrasive grains is formed on the surface of the base material by using a plating bath or a plating bath in which hard abrasive grains are further dispersed in a plating bath or nanocarbon fiber dispersion solution. It is a manufacturing method of the nanocarbon fiber containing electrodeposition tool of Claim 5, It is characterized by the above-mentioned.

  A seventh aspect of the present invention is the method for producing a nanocarbon fiber-containing electrodeposition tool according to the fourth and fifth aspects, wherein the base material is an electroforming mold, and the nanocarbon fiber formed after the formation of the metal plating film It is a manufacturing method of the nanocarbon fiber containing electrodeposition tool including the process of peeling the containing electrodeposition tool from an electric mold.

  Invention of Claim 8 is a base material in which the base material is a constituent part of the electrodeposition tool in the manufacturing method of the nanocarbon fiber-containing electrodeposition tool according to Claims 4 and 5, and the metal plating film It is characterized by being a method for producing a nanocarbon fiber-containing electrodeposition tool including a step of temporarily fixing a single layer of hard abrasive grains to the surface of a base material by electrolytic plating or electroless plating before formation.

  According to the first and second aspects of the invention, since the nano-carbon fiber-containing composite plating film is provided on the outermost surface of the plating portion, the small diameter shaft-attached electric power used for drilling or grooving due to the following factors. The tool life of the grinding wheel is improved, which is superior to the conventional electrodeposition grinding wheels with a small diameter shaft. 1) The mechanical strength of the plating film is improved, and even when a large load is applied to the abrasive grains, deformation of the plating film is suppressed, so that the holding power of the abrasive grains is improved, and the abrasive grains that have a great influence on the tool life Dropping can be suppressed. 2) Since the mechanical strength of the plating film is improved and the wear resistance is improved, the wear of the plating film due to contact with processing scraps is suppressed. 3) The thermal conductivity of the plating film is improved, and the heat exhaustion due to processing is improved. 4) By improving the surface lubricity of the plating film, the processing waste dischargeability is improved and clogging by processing waste is suppressed, so that the processing resistance is kept low.

  In addition, since nanocarbon fibers with a diameter of 10-100 nm and an aspect ratio (= length / diameter) of 5 to 200 are used as the plating reinforcement material, it is possible to improve the performance of extremely thin coatings that were difficult in the past. Become. For example, an electrodeposition grindstone with a very small diameter shaft with a diameter of 0.1 mm or less, with a single abrasive layer and an abrasive grain size of 10 μm or less, the coating film is 5 μm or less, but the nanocarbon fiber Is sufficiently thin to be applicable.

  According to the first and third aspects of the present invention, the consumption of the electrode tool for electric discharge machining having a small diameter or a complicated shape can be suppressed to be low, and the wear resistance is excellent as compared with the conventional electrode tools. The reason is considered as follows. In electric discharge machining, it is said that the amount of consumption of the electrode tool is inversely proportional to the product of the melting point and the thermal conductivity of the electrode material. For this reason, copper having a high thermal conductivity, tungsten, graphite, or the like, which is a high melting point material, is used for the electrode tool. In recent research, it has been reported that electrode consumption can be suppressed by using conductive polycrystalline diamond as an electrode tool. However, it is not possible to make a tool with a fine complex shape or a small-diameter electrode tool with diamond. Have difficulty. Even if the nanocarbon fiber is a multilayer type, it has thermal conductivity comparable to that of diamond, and the single-layer type nanocarbon fiber has thermal conductivity 1.5 times or more that of diamond. By using a composite plating material in which this nanocarbon fiber is combined with copper or the like as an electrode tool, the thermal conductivity of the electrode tool can be improved and consumption can be suppressed. There are two manufacturing methods: 1) a method of applying nano-carbon fiber composite plating to a base metal or a small-diameter base metal having a fine complicated shape, and 2) an electroforming method using an electroforming mold of a fine complicated shape or a small-diameter electroforming mold. A method is conceivable, and an electrode tool having a complicated shape and low consumption can be provided.

  According to the invention of claim 4, by applying ultrasonic vibration in a state where 0.1-2 gram of nanocarbon fibers and a cationic surfactant are added to a plating bath, the nanocarbon fibers at the time of forming the plating film There is an effect that the dispersibility of the resin can be improved and a dense non-porous nanocarbon fiber composite plating film can be formed. By using a cationic surfactant, the eutectoid rate can be increased, which is superior to conventional methods.

  According to the invention of claim 5, there is an effect that a composite plating film containing more nanocarbon fibers can be formed in the plating film.

  According to the invention of claim 6, since the nanocarbon fiber and the hard abrasive can be co-deposited simultaneously, there is an effect that the working time can be shortened. This is particularly effective when abrasive grains having a small particle diameter are used and when hard abrasive grains are desired to be formed in multiple layers. Moreover, since the nanocarbon fiber which hold | maintains an abrasive grain and an abrasive grain can be arrange | positioned closer, there exists an effect that high abrasive grain retention power can be expressed.

  According to the invention of claim 7, by producing an electroforming mold having a fine shape, there is an effect that it is possible to easily produce a plurality of fine-shaped electrodeposition tools in which the electroforming shape is inverted.

  According to the invention of claim 8, the step of fixing diamond to the base metal by forming a structure in which two or more metal plating film layers hold a part of the abrasive grains under the composite plating layer; There is an effect that the process of forming the nanocarbon fiber composite plating layer can be separated and the plating conditions suitable for each can be selected.

  The surface roughness is better than that of the production method of the present invention, and a hard and dense composite plating film can be formed for the following reason. In the plating process, by applying ultrasonic vibration to the plating bath, nanocarbon fibers that are easily re-aggregated can always be dispersed in a substantially single state. Therefore, the nanocarbon fiber can be taken in at the time of plating formation, and a dense composite plating film that is not porous can be formed. In the case of rotating agitation, the dispersion state is poor, and agglomeration and a plurality of nanocarbon fibers are incorporated into the composite plating film in a crosslinked state, and do not enter the plating between the nanocarbon fibers, resulting in a porous composite plating film. .

  In addition, due to the action of the cationic surfactant used as a dispersant, the nanocarbon fibers having a positive charge are efficiently collected on the base material serving as the cathode, and the eutectoid rate of the nanocarbon fibers incorporated into the composite plating film As a result, a dense composite plating film can be formed.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  1 and 2 show an embodiment of the present invention, FIG. 1 is an enlarged cross-sectional view including abrasive grains and an electrodeposition layer of an electrodeposition grindstone, and FIG. 2A is a front view of the tip of an electrodeposition grindstone with a small diameter shaft. . FIG. 2B is a cross-sectional view taken along the line A-A ′ of the small diameter tool shown in FIG. 2A. 3A and 3B show an example of an electrode tool for electric discharge machining. 4A, 4B, 4C, and 4D are views showing a manufacturing method according to the present invention.

  In FIG. 1, 10 is a base metal, 12A is a first plating film, 12B is a second plating film, 14 is a composite plating film, 16 is a nanocarbon fiber, 18 is a hard abrasive grain, and 20 is a multilayer plating film. In FIG. 4A, 30 is an electrode, 32 is a plating bath in which nanocarbon fibers are dispersed, 34 is a temperature control bath, 36 is an ultrasonic vibration device, 38 is a slip ring, and 40 is a motor. In FIG. 4C, 42 is an electroforming mold, and 44 is an electrode tool.

  In the manufacture of an electrodeposition grindstone with a small-diameter shaft, cylindrical carbide, high-speed steel, and stainless steel having a diameter that is smaller than the finished tool diameter by twice the abrasive particle diameter are used as the base metal. In consideration of processing waste discharging performance, the base metal may be formed with a spiral groove such as a drill, a straight groove, or a side cut, or may have a hemispherical tip shape, an obliquely inclined shape, or the like.

  In the manufacture of a surface coating type small-diameter electrode tool for electric discharge machining, copper is used as a base metal.

  As hard abrasive grains, the grain size is 1/5 to 1/200 of the diameter of the electrodeposited wheel, and preferably about 1/10 of the diameter of the electrodeposited wheel. In this case, diamond having an average particle diameter of 10 μm, cBN, or the like is used. For an electrodeposition grindstone with a diameter of 0.5 mm, diamond, cBN, etc. with an average particle diameter of 50 μm are used.

  The embedding rate of hard abrasive grains is preferably 60-80% of the abrasive grain diameter.

  The electrode tool for electric discharge machining includes an electrode tool for engraving electric discharge machining for transferring an electrode shape to a workpiece, and an electrode tool for generating electric discharge machining having a cylindrical shape or a cylindrical shape for use while scanning while rotating. FIG. 3A is an electrode tool for generating electric discharge machining, and FIG. 3B is an electrode tool for electric discharge machining. FIG. 3A is an example of an electrodischarge machining electrode tool formed by electroforming, and the tool is composed only of a nanocarbon fiber composite plating material containing copper as a main component. An electrode tool having a structure in which the surface of a cylindrical base metal is covered with composite plating may be used.

  FIG. 3B is an example of an electrode tool for engraving electric discharge machining in which nanocarbon fiber composite plating is formed on a base metal having a fine complex shape. Copper, tungsten, graphite, or the like is used for the base metal. An electrode tool may be used in which only a nanocarbon fiber composite plating material containing copper as a main component is formed by electroforming without using a base metal.

  The composite plating film consists of a plating bath in which nanocarbon fibers of 2 g / L (g / L represents the gram weight of nanocarbon fibers contained in 1 liter of plating solution) are dispersed with a cationic surfactant. In the process of forming a composite plating film containing nickel or copper as the main component, the base material is rotated as necessary, and ultrasonic plating is applied to the plating bath constantly or intermittently. It is obtained by using an electrolytic plating method.

  As the nanocarbon fiber, single-walled carbon nanotubes or multi-walled carbon nanotubes (aspect ratio: 5-200, diameter: 10-100 nm) are preferably used.

(Explanation of the method for manufacturing electrodeposited whetstone with small diameter shaft)
Next, the manufacturing method of the electrodeposition tool of this invention is demonstrated according to FIG. 4B.

  1) Wash and degrease the base metal and perform pretreatment such as electroless plating if necessary. 2) Abrasive grains are temporarily fixed to a base metal by electrolytic plating with hard abrasive grains that act on the processing. The thickness of the plating layer is preferably about 20% of the abrasive grain size. 3) In the case of a multilayer plating structure, a plating film is formed by electrolytic plating or electroless plating. 4) For the nanocarbon composite plating, using the apparatus shown in FIG. 4A, a plating bath in which 0.1 to 2 grams of nanocarbon fiber per liter is dispersed with a cationic surfactant is maintained at a constant temperature, and the nanocarbon fiber is regenerated. In order to prevent agglomeration, in the case of an electrodeposition tool that is axisymmetric, especially in a state where it is placed in a water bath, the water bath is placed on an ultrasonic vibrator, and ultrasonic vibrations are constantly or intermittently applied to the plating bath. 1 forms a nanocarbon fiber composite plating film as shown in FIG. 1 by electrolytic plating or electroless plating while rotating the base material as necessary. When the method of co-depositing hard abrasive grains and nanocarbon fibers is employed, composite plating is performed by the process of 4) using a plating bath in which hard abrasive grains and nanocarbon fibers are dispersed after the process of 1). The hard abrasive grains and nanocarbon fibers are co-deposited simultaneously.

  The frequency of the ultrasonic wave is preferably about 15 kHz to 100 kHz. As a method of applying ultrasonic vibration, an ultrasonic vibration horn may be directly introduced into the plating bath and the vibration may be applied.

As the bath used for electroplating, nickel plating bath such as Watt bath and sulfamic acid bath, copper plating bath such as copper sulfate bath and copper cyanide bath are preferable, and as electroless plating bath, electroless Ni-P A bath, an electroless Ni-B bath, an electroless Ni-WP bath, an electroless Ni-WB bath, an electroless copper bath, and the like are preferable. Here, Ni represents nickel, B represents boron, P represents phosphorus, and W represents tungsten. For example, nickel sulfamate plating bath (NiHSO ₃ · NH ₂ : 500 g / L, NiCl · 6H ₂ O: 4 g / L, H ₃ BO ₃ : 33 g / L) and multi-walled carbon nanotubes (φ60-100 nm, length 1 -2 μm), the current density is 5A / dm ² or less and the plating temperature is 40-50 ℃. In addition, even if the amount of multi-walled carbon nanotubes is 2 g / L or more, significant performance improvement cannot be expected. The amount of the cationic surfactant is suitably about 30 wt% of the multi-walled carbon nanotube. As the cationic surfactant, an amine salt type or an ammonium salt type is suitable.

  Next, a method for producing the small-diameter electrode tool for electric discharge machining according to the present invention by electroforming and coating will be described with reference to FIGS. 4C and 4D, respectively.

(Explanation of EDM electrode tool by electroforming)
1) Pretreatment such as washing and degreasing of the electroforming mold is performed. 2) Using the apparatus of FIG. 4A, a composite plating film is formed in the same manner as in step 4) of the method for producing an electrodeposited grinding wheel with a small diameter shaft. 3) Finally, the electroforming mold is peeled off.

(Description of EDM electrode tool by coating method)
1) Pretreatment such as base metal processing, washing, degreasing, and electroless plating as necessary. 2) Using the apparatus of FIG. 4A, nanocarbon fiber composite plating coating is performed by electrolytic plating while applying ultrasonic waves as in the case of the electrodeposition grindstone with a small diameter shaft.

FIG. 5 is a comparison diagram of the breaking strength (shear strength) of the single-grain abrasive grains held in the composite plating film of the present invention and a normal plating film by a shear test. For the shear test, a Dage bond tester series 4000 equipped with a single crystal diamond tool having a test surface width of 150 μm and a load cell of a maximum of 20 N was used. The tool tip was 10 μm high from the plating film surface. The tool was moved parallel to the plating film surface at a speed of 100 μm / s, the abrasive grains exposed from the plating film were pressed, the strength when the abrasive grains dropped was measured, and this was taken as the breaking strength. In the shear test sample, diamond abrasive grains with a regular cubic octahedral structure and an average grain size of 100μm (GE MBG660) are fixed on a flat metal base metal with a two-layer nickel plating film, and the protruding amount is about The thickness was 50 μm. The lower layer plating was formed by a normal nickel sulfamate plating bath, and the plating film thickness was 30 μm. The upper layer (outermost layer) is plated with a nickel sulfamate plating bath (NiHSO ₃ · NH ₂ : 500 g / L, NiCl · 6H ₂ O: 4 g / L, H ₃ BO ₃ : 33 g / L) and nanocarbon fiber (Multi-walled carbon nanotube: diameter 60-100 nm, length 1-2 μm) was formed using a plating bath in which 0 g / L, 0.5 g / L, and 1.0 g / L were dispersed, and the composite plating film thickness was 20 μm. The composite plating conditions were a current density of 5 A / dm ² , a plating bath temperature of 50 ° C., and constant ultrasonic agitation (frequency 42 kHz). From FIG. 5, it was found that the composite plating film of the present invention produced by a plating bath containing 1.0 g / L of nanocarbon fibers had a shear strength about twice that of the normal plating film. The shear strength expresses the adhesive strength between the diamond abrasive grains and the plated coating and the strength of the plated coating against deformation. The inclusion of nanocarbon fibers improves the abrasive retention of the plated coating. I was able to confirm.

In order to confirm the effect when the nanocarbon fiber composite plating film is applied to an electrodeposition grindstone, the results of processing tests comparing tool life of the conventional electrodeposition grindstone and the nanocarbon fiber-containing electrodeposition grindstone according to the present invention are shown. For processing tests, with a carbide base metal, diamond with an average abrasive grain size of 50μm (GE MBG600) fixed with two layers of nickel plating film at a filling rate of 60%, with a small diameter shaft of 0.5mm and 3mm An electrodeposition grindstone was used. The lower plating film was formed by a normal nickel sulfamate plating bath, and the plating film thickness was 15 μm. The upper layer (outermost surface layer) is a nickel sulfamate plating bath (NiHSO ₃ · NH ₂ : 500 g / L, NiCl · 6H ₂ O: 4 g / L, H ₃ BO ₃ : 33 g / L), nanocarbon Fibers (multi-walled carbon nanotubes: diameter 60-100 nm, length 1-2 μm) were formed using a plating bath in which 0 g / L and 1.0 g / L were dispersed, and the composite plating film thickness was 15 μm. The composite plating conditions were a current density of 5 A / dm ² , a plating bath temperature of 50 ° C., ultrasonic stirring (frequency of 42 kHz), and workpiece rotation speed of 24 min ⁻¹ .

Using the electrodeposition grindstone with small diameter shaft of 3mm in diameter, side processing of 1.0mm thick white sheet glass was performed under the processing conditions of tool rotation speed 5000min- ¹ , feed rate 500mm / min, cutting depth 50μm, tool breakage The machining distance (= tool life) up to is shown in FIG. From FIG. 6, it was found that the nanocarbon fiber-containing electrodeposition tool of the present invention has an average tool life of 8 times that of a conventional tool.

Using the electrodeposition grindstone with a small diameter shaft of 0.5 mm in diameter, step processing was performed at a tool rotation speed of 15000 min ^-1 , a feed rate of 1.5 mm / min, and a step amount of 0.06 mm. 7A and 7B show electron microscope images of the bottom surface of the tool after processing 10 holes of 4 mm in length. Here, the step machining is a machining method in which the cutting edge of the tool is pulled back to the entrance of the machining hole every time the depth corresponding to the step amount is machined in order to discharge chips out of the hole. From FIG. 7A, the conventional tool showed remarkable drop | off of the abrasive grain in the center part of the grindstone bottom face. On the other hand, from FIG. 7B, it was confirmed that the electrodeposition tool of the present invention had almost no falling off of abrasive grains and a long tool life.

In order to confirm the effect when the nanocarbon fiber nickel composite plating film is applied to the electrode tool for electric discharge machining, FIG. 8A shows a machining test result comparing electrode tool consumption with respect to the workpiece machining amount with or without nanocarbon fibers. In the machining test, an electric discharge machining of a φ2 mm stainless steel material was performed using an electrode tool in which a Cu material was plated with a nanocarbon fiber composite nickel plating film of about 50 μm and normal nickel plating. The electrical discharge machining conditions were electrode polarity (+), current value 8A, pulse width 2 μs, pause time 128 μs, machining fluid EDF-K (manufactured by Mitsubishi Oil Corporation), and a transistor circuit was used. The electrode tool used in the experiment was a nickel sulfamate plating bath containing 0.5 g / L of nanocarbon fibers (multi-walled carbon nanotubes, diameter 60-100 nm, length 1-2 μm, thermal conductivity 1812 ± 300 W / mK). (NiHSO ₃ · NH ₂ : 500 g / L, NiCl · 6H ₂ O: 4 g / L, H ₃ BO ₃ : 33 g / L), current density 5A / dm ² , plating bath temperature 50 ° C, always ultrasonic It was produced under the plating conditions of stirring (frequency 42 kHz) and workpiece rotation speed 24 min- ¹ . From FIG. 8A, it was found that the consumption amount of the nanocarbon fiber composite plating electrode tool was about one-half that of the normal plating electrode tool.

In order to confirm the effect at the time of applying the nanocarbon fiber copper composite plating film to the electrode tool for electric discharge machining, FIG. 8B shows a machining test result comparing electrode tool consumption with respect to the workpiece machining amount with and without nanocarbon fibers. In the machining test, electric discharge machining was performed on a stainless steel material having a diameter of 0.8 mm using an electrode tool obtained by subjecting a stainless steel material to an about 100 μm nanocarbon fiber composite copper plating film and normal copper plating. The electrical discharge machining conditions were electrode polarity (+), current value 8A, pulse width 2 μs, pause time 128 μs, machining fluid EDF-K (manufactured by Mitsubishi Oil Corporation), and a transistor circuit was used. The electrode tool used in the experiment was a copper sulfate plating bath containing 1.0 g / L of nanocarbon fibers (multi-walled carbon nanotubes, diameter 60-100 nm, length 1-2 μm, thermal conductivity 1812 ± 300 W / mK) ( CuSO ₄ · 5H ₂ O: 200 g / L, H ₂ SO ₄ : 50 g / L, Cl: 50 mg / L), current density 5A / dm ² , plating bath temperature 35 ° C It was made with. From FIG. 8B, it was found that the consumption of the nanocarbon fiber composite plating electrode tool was about one-half that of the electrode tool for normal plating. Moreover, it turned out that the consumption of a nanocarbon fiber composite plating electrode tool is about 2/3 compared with the case where a pure copper plate is used as an electrode tool.

  9A, 9B, and 9C show a manufacturing method of the present invention using a plating bath in which nanocarbon fibers (φ60-100 nm, length 1-2 μm, multi-walled carbon nanotubes) are dispersed at 0.25 g / L. The electron micrograph of the plating film surface formed using the conventional manufacturing method is shown. FIG. 9A and FIG. 9B are electron micrographs of the surface of the plating film formed at a rotational speed of 200 rpm and 500 rpm, respectively, by conventional rotary stirring using a stirrer. From FIG. 9A and FIG. 9B, although a slight improvement can be seen by increasing the number of revolutions, the plating film is in a very porous state and cannot hold the abrasive grains very much. On the other hand, FIG. 9C is an electron micrograph of the surface of the plating film formed by the production method of the present invention using ultrasonic vibration, and it can be seen that a dense plating film is formed. The surface roughness Ra of the plating film formed by the conventional stirring method at a rotational speed of 200 rpm and 500 rpm is 2.51 μm and 1.95 μm, respectively, whereas the surface roughness Ra of the plating film formed by the manufacturing method of the present invention is 0.28 μm, and an improvement effect of the surface roughness of 7 times or more was confirmed.

  Moreover, from FIG. 10 showing the relationship between the amount of nanocarbon fibers contained in the plating bath and the Vickers hardness of the plating film, 1.0 g / n of nanocarbon fibers (multi-walled carbon nanotubes, φ60-100 nm, length 1-2 μm) are obtained. It can be confirmed that the plating film formed using a plating bath in which L or more is dispersed has a hardness of 2.5 times or more that of the plating film not containing nanocarbon fibers, and the production method of the present invention is a very dense composite. It was found that the plating film can be formed, and the mechanical properties of the formed nanocarbon fiber composite plating film are greatly improved compared to the nickel simple plating film.

  FIG. 11 is an electron micrograph showing the state of nanocarbon fibers (multi-walled carbon nanotubes: diameter 60-100 nm, length 1-2 μm) in the nickel plating film. The nanocarbon fiber-containing nickel plating film was formed by electrolytic plating of a nickel sulfamate bath using the production method of the present invention. In order to observe the state of the nanocarbon fibers, the nanocarbon fiber-containing nickel plating film was etched using a nickel plating release agent to expose the nanocarbon fibers. From FIG. 11, it was clearly confirmed that nanocarbon fibers were contained in the nickel coating.

  Further, from the electron micrograph of the composite plating film containing the hard abrasive grains formed by the production method of the present invention shown in FIG. 12, it was confirmed that even if the abrasive grains were contained, it was a dense plating film.

It is an expanded sectional view containing the grain and electrodeposition layer in the electrodeposition grindstone of the present invention. It is a front view of the tip of the electrodeposition grindstone with a small diameter shaft of the present invention. It is A-A 'sectional drawing of FIG. 2A. It is a figure which shows the structural example of the electrode tool for cylindrical small diameter electrical discharge machining by an electroforming method. It is a figure which shows the structural example of the electrode tool for fine electrical discharge machining by composite plating coating. It is a figure which shows an example of the apparatus of the nano carbon fiber composite plating by this invention. It is a figure which shows the preparation procedures of the electrodeposition grindstone with a small diameter shaft by this invention. It is a figure which shows the preparation procedures of the electrode tool for electric discharge machining by the electroforming method by this invention. It is a figure which shows the preparation procedures of the electrode tool for electric discharge machining by the plating coating by this invention. Comparison diagram by shear test of abrasive grains held in composite plating film of present invention and normal plating film It is a comparison figure of the tool life by the processing example (side surface processing) of the electrodeposition grindstone with a small diameter shaft of this invention, and the normal electrodeposition grindstone with a small diameter shaft. It is an electron micrograph of a normal electrodeposition grindstone with a small diameter shaft in which 10 holes of 0.5 mm in diameter and 4 mm in depth are processed in quartz glass. 4 is an electron micrograph of an electrodeposited grinding wheel with a small-diameter shaft according to the present invention in which 10 holes with a diameter of 0.5 mm and a depth of 4 mm are processed in quartz glass. It is a comparison figure of the tool life by the example of a process of the electrode tool for electric discharge machining using the Ni plating film of the present invention, and the electrode tool for usual electric discharge machining. It is a comparison figure of the tool life by the example of processing of the electrode tool for electric discharge machining using the Cu plating film of the present invention, and the usual electrode tool for electric discharge machining. It is an electron micrograph which shows the composite plating film formed with the manufacturing method using rotation stirring (200min-1). It is an electron micrograph which shows the composite plating film formed with the manufacturing method using rotation stirring (400min-1). It is an electron micrograph which shows the composite plating film formed with the manufacturing method of this invention which added ultrasonic vibration. It is a graph which shows the relationship between the Vickers hardness of the composite plating film formed densely by the manufacturing method of this invention, and the amount of nanocarbon fibers in a plating bath. It is the electron micrograph of the nano carbon fiber in the composite plating film which exposed the composite plating film formed densely by the manufacturing method of this invention using the nickel plating release agent. It is an electron micrograph of the composite plating film containing the hard abrasive grain formed densely by the manufacturing method of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10: Base metal 12A: 1st plating film 12B: 2nd plating film 14: Composite plating film 16: Nanocarbon fiber 18: Hard abrasive grain 20: Multilayer plating film 30: Electrode 32: Plating bath in which nanocarbon fiber is dispersed 34: Temperature control bath 36: Ultrasonic vibration device 38: Slip ring 40: Motor 42: Electric mold 44: Electrode tool

Claims (8)

Coating mainly the by Runi nickel electroplating, at least one coating film mainly composed of by Runi nickel in an electroless plating, or by that copper electroplating selected from coating mainly Among them, nanocarbon fibers having a diameter of 10 to 100 nm and an aspect ratio (= length / diameter) of 5 to 200 are uniformly contained, and 1.1 times that of the plating film having the hardness not including the nanocarbon fibers. A composite metal plating film having a Vickers hardness of ~ 2.5 times is disposed at least on the outermost surface ,
The composite plating film is a nanocarbon fiber-containing electrodeposition tool formed on a cylindrical or cylindrical base material surface, and the plating film has a diameter of 1/5 to 1/200 of the diameter of the electrodeposition tool. 3 mm diameter containing hard abrasive grains and the nanocarbon fiber having a length equal to or less than the diameter of the abrasive grains, and fixing the hard abrasive grains to the base material with a part of the hard abrasive grains of the outermost surface layer exposed. The following nanocarbon fiber-containing electrodeposition tools.   The nanocarbon fiber-containing electrodeposition tool according to claim 1, wherein the composite plating film is an electrode tool for electric discharge machining arranged on an electric discharge machining surface.   The nanocarbon fiber-containing electrodeposition tool according to claim 1 or 2, wherein the base material is formed with a spiral groove or a straight groove. A plating bath in which 0.1 to 2 grams of nanocarbon fiber per liter is dispersed with a cationic surfactant is used, and the base material is immersed in the plating bath in the process of forming a metal plating film mainly composed of nickel or copper. and, while applying ultrasonic vibration to the plating bath, by electrolytic plating or electroless plating, one nanocarbon fiber-metal composite plating film claims 1 to characterized in that formed on the base material surface of 3 A method for producing a nanocarbon fiber-containing electrodeposition tool according to claim 1. After dispersing the nanocarbon fibers in pure water or water with a polar surfactant, the base material is immersed in the solution, and the nanocarbon fibers are fixed to the base material surface by electrophoresis, and then nickel or copper In the process of forming a metal plating film containing as a main component, a base material is immersed in the plating bath, and a nanocarbon fiber composite metal plating film is formed on the surface of the base material by electrolytic plating or electroless plating. The method for producing a nanocarbon fiber-containing electrodeposition tool according to any one of claims 1 to 3 . The base material is a base material that is a constituent part of the electrodeposition tool, and the nanocarbon fiber and the hard abrasive grains are used by using the nanocarbon fiber dispersion plating bath or a plating bath in which hard abrasive grains are further dispersed in the nanocarbon fiber dispersion solution. A method for producing a nanocarbon fiber-containing electrodeposition tool according to any one of claims 1 to 3 , wherein a metal-plated film containing s is formed on the surface of the base material. The nanocarbon fiber-containing electrode according to any one of claims 1 to 3, further comprising a step of peeling the formed nanocarbon fiber-containing electrodeposition tool from the electrode mold after forming the metal plating film. A method for manufacturing a tool. The base material is a base material that is a constituent part of an electrodeposition tool, and includes a step of temporarily fixing a single layer of hard abrasive grains to the surface of the base material by electrolytic plating or electroless plating before forming the metal plating film. Item 4. A method for producing an electrodeposition tool containing nanocarbon fibers according to any one of Items 1 to 3 .