JPS606360A - Carbon fiber buff and electrolytic-polishing therewith - Google Patents

Abstract

PURPOSE:To have conductive materials such as metal or the like efficiently polished electrolytically by pressing a carbon fiber buff as a cathode against a work as an anode, with electrolytic solution included in their contact area. CONSTITUTION:A buff comprises a buffing member made of a bias-cut carbon fiber cloth 1 which is engaged and fixed by a fastening ring 2, a metallic center plate 3 being mounted on the ring 2. Polishing is performed, using the buff 5 as a cathode and a work 6 as an anode, while running electrolytic solution 7 through the area where the buff 5 contacts to the work 7. With this method, polishing speed can be increased, so that polishing efficiency also can be improved extremely. Surface roughness can be decreased by pulverized abrasive mixed in the electrolytic solution 7.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a carbon fiber puff for electrolytic polishing comprising a puff member made of a carbon fiber woven fabric and a conductive support member that supports and fixes the puff member, and a carbon fiber puff for electrolytic polishing that uses the puff to polish gold IA or the like. Conductive material (
(including composite materials).

BACKGROUND ART Methods for processing conductive materials such as metals by electrochemically dissolving them include electrolytic polishing, electrolytic machining, and electrolytic grinding, and these have already been put into practical use.

In this processing method, the workpiece is used as an anode and an electrolyte is interposed between it and the counter electrode (cathode). However, if the workpiece and the counter electrode come into contact during processing, a short circuit occurs. As a result, a large short-circuit current flows, resulting in significant damage to the workpiece and the counter electrode. For this reason, in the electrolytic polishing method and the electrolytic processing method, electrolysis is performed while maintaining an excessive gap between the two electrodes. Further, the processing mechanism of the electrolytic grinding method is based on the fact that the non-conductive abrasive grain protrusions in the grinding wheel prevent the two poles from shorting.

On the other hand, in the electrolytic polishing method using the carbon fiber puff of the present invention, the carbon fiber puff serving as a cathode and the workpiece serving as an anode are brought into contact with each other, and an electrolytic solution is applied to the contact portion while applying pressure to create contact. This is a method of electrochemically polishing a workpiece by intervening.

In this method, the puff and the workpiece come into contact, so naturally,
It is common sense to think that electrochemical processing is impossible due to a short circuit flowing between the two, but during electrolytic polishing, there is a large potential gradient on the surface of the outermost layer of the carbon fiber puff that comes into contact with the workpiece. As a result, when the current efficiency is in the range of 50 to 100%, the workpiece undergoes positive Vm melting, and the rotating puff removes the positive melted metal, further promoting electrolysis. It has been discovered that metals can be polished with high efficiency by doing so.

As long as the puff of the present invention is composed of a puff member made of a carbon fiber woven fabric and a conductive support member that supports and fixes the puff member, the structure of the puff (morphological characteristics 'a) is particularly limited. There is no need for this invention; for example, the configuration of the present invention may be applied to a currently widely used puff, such as a pleated bias cotton puff. Depending on the purpose, a small puff with a shaft or a wrap It is also effective for the electrolytic polishing method of the present invention to support and fix it on a rotating disk as a disk pouch/knopping cloth.

The carbon fiber used in the puff of the present invention is preferably a high-strength, high-elasticity carbon fiber with a tensile strength of 200 kgf/mm2 or more and a tensile modulus of 20,000 kgf/mm2 or more in terms of the rotational strength and durability of the puff. Tensile strength'E I O
Okgf/mm2 or more, tensile modulus 4000kgf
Any type of carbon fiber can be used for the purpose of the present invention.

EXAMPLES The present invention will be explained in detail with reference to Examples below.

Example 1 Tensile strength: 2300 kgf/mm, tensile modulus: 23oo
Using carbon fiber thread of okgf/mm2, thickness 20.4
A plain weave woven fabric having a thickness of 1.0 mm was obtained, and the puff shown in FIG. 1 was made in the same form as a conventional pleated bias cotton puff by using the carbon fiber woven fabric instead of the cotton fabric. That is, a puff member made of a bias-skirted carbon fiber woven fabric 1 is clamped and fixed with a metal claw @ fastening ring 2, and a metal 7 with a hole diameter matching the rotation axis of the polishing machine is attached to the ring. The interface plate 3 was attached to a fastening ring with claws to form a puff. In order to give the puff appropriate rigidity and improve its durability, concentric suture lines 4 were inserted using threads made of the same material as the carbon fiber woven fabric. The dimensions of the puff were an outer diameter of 20111 m, a ring inner diameter of 75 mm, and a width of about 20 mm. FIG. 2 is an explanatory diagram showing an outline of the electrolytic polishing apparatus. The puff 5 was attached to the polishing device shown in FIG. 2, the puff was used as a cathode, the workpiece 6 was used as an anode, the number of rotations of the puff was 2000 rpm, and the pressure of the puff was 1 kgf/am.
Polishing was carried out with an electrolytic current of 20 A/cm" and electrolytic solution 7 flowing at a flow rate of 50 ml/B between the puff and the workpiece. The electrolytic solution was made by adding sodium chloride to water + aag
Salt solution with /l added and sodium nitrite added for corrosion protection at log/l! However, any electrolytic solution used in conventional electrolytic processing may be used, and it was filtered and circulated with a pump before use. Polishing is performed only at the contact area of the puff, and the polishing speed (polishing depth/polishing time) is 4.5 μm.
I missed it at /s. This corresponds to several tens to hundreds of times the polishing speed of conventional puff polishing, and the polishing efficiency has increased dramatically. The surface roughness of the polished surface is approximately 1μ R+naX″C
'Rarely. By mixing fine powder abrasives such as silicon carbide, alumina, and oxidized aluminum into the electrolytic solution, the surface roughness could be further reduced. The effect varies depending on the type and particle size of the abrasive mixed, but 10 to 20 g of chromium oxide
/J, a smooth surface of 0.1 μm RmaX was obtained.

In addition, puff rotation speed 2000 rpm, huff pressure 1 kgf
The polishing rate changes as shown in FIG. 5 when the electrolytic current is changed with Am2 constant, and the polishing rate increased linearly with the increase in current (J).

Example 2 The outline is shown in Fig. 3. This method is an attempt to more efficiently perform wrapping using a conventional lapping machine, and a plastic date plate 9 of the same diameter for Zetsushin is glued onto a metal rotating disk 8. A carbon fiber woven fabric 10 that is thicker than the diameter of the rotating disk is placed on top, and the outer peripheral end is supported and fixed on the side surface of the rotating disk with a metal ring 11. The cloth 10 was made of carbon-based fibers with the same strength as in Example 1, and was a satin weave cloth with a thickness of 0.5 mm.This carbon fiber puff disk was used as a negative electrode, and the workpiece 12 was connected to the anode. Puff rotation speed: 450 rpm, puff pressure + kgf/am", electrolytic current: 5 A/am",
The same electrolytic solution 13 as in Example 1 was applied to the contact area of the workpiece.
Polishing was performed while flowing at a flow rate of 50 m1A. The polishing rate was 1 μm/B. The surface roughness of the polished surface is o, 8 μm
It was Rmax. As in Example 1, surface roughness can be reduced by mixing fine powder polishing ions into the electrolyte, and although the effect varies depending on the type and particle size of the abrasive, 〇Example 3 Tensile strength e 12 (1 kgf/mX, tensile strength 4 elastic skewers 4
Using yarn made of carbon fiber of 800 kgf/mI2+2, a twill weave fabric with a thickness of 0.4 mm was obtained, and a piece 19 of the woven fabric was obtained.
was placed on a metal upper shaft 21 having a diameter of 6 mm, and firmly fixed to the metal upper shaft 21 with an adhesive such as epoxy resin at 2°, and then integrated to form the glazed puff shown in FIG. This puff with a shaft was attached to a hand-held portable polishing machine, the puff shaft was connected to the shade rod, the workpiece was connected to the anode, and the polishing was performed by applying electricity between the two electrodes while pouring electrolyte, and the polishing was performed efficiently. Ta. This method 1 is suitable for polishing objects with complex curved surfaces, such as molds.

Nao, in the electrolytic polishing method of the present invention, the main purpose of rotating the puff is to quickly remove the metal dissolved in the anode and promote electrolysis, so the polishing speed can be changed by changing the rotation speed. unaffected.

The electrolytic polishing method according to the present invention has the following features.

(1) The polishing rate increases in proportion to the current density (A/Cm2), and a maximum polishing rate of 10 μm/e can be obtained, and the polishing efficiency is dramatically increased compared to conventional puff polishing.

(2) Polishing is performed only on the area where the puff comes into contact, and as the puff suppression is large, the electrolytic current increases and polishing can be performed quickly. (3) Due to the appropriate flexibility of the puff surface, it easily conforms to the free-curved surfaces of Q and H workpieces, making it easy to polish curved surfaces. (4)
w; As a workpiece, it can be applied to metal materials, conductive non-metal materials, and composite materials thereof, so it has a wide range of applications. (5) Unlike conventional puff polishing, no dust is generated and a clean working environment can be maintained.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a carbon fiber puff for electrolytic polishing in Example 1. FIG. 2 is a schematic explanatory diagram of an apparatus for electrolytic polishing in Example 1. FIG. 3 is a schematic explanatory diagram of an apparatus for electrolytic polishing in Example 2. Figure 4 shows Example 3.
Fiber puff for electrolytic polishing, 6.12... Workpiece, 7.13... Electrolyte, 14.22... Cover, 15.17... Filter, 16, 1B...
···pump. 35 Figure 2 'IIEA vHN (A, /am-) Figure 3 = 328-

Claims (1)

[Claims] 1. A puff member is formed using a woven fabric made of charcoal tm fiber yarn having a tensile strength f' of 100 kgf/nun2 or more and a tensile modulus of 4000 kgf/ωm2 or more, and the puff member is electrically supported. A carbon fiber puff for electrolytic polishing characterized by being supported and fixed by a member. 2. A puff member is formed using a woven fabric made of carbon fiber yarn with a tensile strength of 2100 kgf/mIn2 or more and a tensile modulus of 4000 kgf/mIn2 or more, and the puff member is supported by a conductive support member and fixed with carbon fibers. Using the fiber puff as a cathode and the workpiece as an anode, the rotating puff and the workpiece are brought into contact with each other,
An electrolytic polishing method characterized by electrolytically polishing a conductive material such as metal by interposing an electrolyte in the contact area and passing current between the two electrodes.