JPH06959B2 - High-speed electrolytic rough finishing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] In recent years, it has been required to highly mirror-finish the surface of a stainless steel plate or the like, and the present inventors first realize it by electrolytic polishing. Proposing a method. Due to its processing mechanism, this electrolytic abrasive grain polishing method is a super-mirror finishing method mainly for the submicron region.

The present invention relates to a high-speed electrolytic rough finishing method suitable for obtaining a ground for super-mirror finishing by such electrolytic abrasive grain polishing, and more specifically, a plate material or a pipe inner or outer surface made of stainless steel or the like is The present invention relates to a method of performing rough finishing at high speed by electrolysis.

[Prior Art] Electrolytic machining has a potential problem comparable to cutting in terms of high-efficiency machining, although there is a precision problem. This electrolytic processing is generally considered important for application to a three-dimensional shape (processing in mm) such as punching and cutting the work by feeding the electrode in the depth direction to the work. However, recently, high-efficiency machining characteristics in the surface rough finishing in the unit of μm have been attracting attention.

For example, in the Institute of Electrical Machining, Vol. 20, No, 40, P. 1 to 13, Sakai and Masawa have made a research report on high-speed electrolytic finishing of a wire electric discharge machined surface. This electrolytic finishing method is intended for the wire electric discharge machining surface, and since the cutout remaining after cutting out the product by electric discharge machining has a shape that is the inverse of the product shape, it is used as a counter electrode for the product and both are evenly It is held in a stationary state through a gap, and electrolytic processing is performed while supplying a necessary electrolytic solution between them.

However, such an electrolytic finishing method is based on the premise that the product to be surface-finished and the counter electrode are opposed to each other and held in a stationary state, and are expected to be applied to large-area plate materials and pipe materials. It has not been.

[Problems to be Solved by the Invention] The technical problem of the present invention is to provide a lower surface of a stainless steel material for electrolytic abrasive grain polishing which requires removal of a work-affected layer of about 10 μm, or a surface of a material to be polished equivalent thereto. The purpose of the present invention is to obtain a method for highly efficiently rough-finishing the surface of a material having a large area to the extent that line feeding relative to the electrode tool is required.

[Means for Solving the Problems] In the high-speed electrolytic rough finishing method of the present invention for solving the above problems, when a plate material is to be polished, an electrode plate provided over the polishing width of the plate material is used. Through a flow path inside the electrode tool to which the electrode plate is attached, the electrolytic solution is supplied to the gap between the electrode plate and the plate material to be polished, and the electrode plate is placed on the surface of the plate material. While moving relatively along the direction of the plate material between the plate material and the electrode plate,
It is characterized in that a current for electrolysis for removing the work-affected layer of about 10 μm is passed to roughen the surface of the plate material at a high speed by electrolytic processing.

When the inner and outer surfaces of the pipe material are to be polished, the electrode plates are opposed to the inner peripheral surface or the outer peripheral surface of the pipe material with a minute gap, and the gap between the electrode plate and the pipe material to be polished is set. While supplying the electrolytic solution and relatively moving the electrode plate in the axial direction of the pipe material, between the pipe material and the electrode plate, 10 μ of the surface of the pipe material is provided.
It is characterized in that the inner surface or the outer surface of the pipe material is rough-finished at a high speed by an electric current by applying an electric current for electrolytic processing for removing a work-affected layer around m.

[Operation] According to the above high-speed electrolytic rough finishing method, the electrode plate is relatively moved along the surface of the object to be polished, and the electrolytic solution is supplied between the surface and the electrode plate while the current for electrolysis is supplied. The surface of the stainless steel material for electrolytic abrasive grain polishing that requires removal of the work-affected layer of about 10 μm by flowing, or the surface of the material to be polished equivalent to that, which is a line relative to the electrode tool. It becomes possible to highly efficiently rough finish the surface of a material that is large enough to require feeding by electrolytic processing.

[Examples] Examples of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a state in which the high-speed electrolytic rough finishing method of the present invention is applied to a stainless steel (SUS) plate material 1. The electrode tool 2 used for carrying out this high-speed electrolytic rough finishing method is provided over the polishing width of the plate material 1 to be polished. For example, when the width of the plate material 1 to be polished is 1.5 m,
It is provided over substantially 1.5 m. This electrode tool 2
Is provided with an electrode plate 3 along one side thereof, and a flow path 5 for supplying an electrolytic solution is formed through the inside of the electrode tool 2 into a gap 4 between the electrode plate 3 and the plate material 1 to be polished. To be done.
In order to stably flow the electrolytic solution toward the gap 4, it is possible to cover the surface of the electrode tool 2 with the insulating material 6 between the flow path wall on the side opposite to the gap 4 and the plate material 1. The electrolyte is sealed against outflow within a range.

The electrode tool 2 can be fixedly installed on the electrolytic rough finishing device to feed the plate material 1 placed on the processing table 7 in the direction of arrow A. The reverse direction is also possible. Alternatively, the plate material 1 may be fixedly arranged without being fed, and the electrode tool 2 may be fed to the plate material in either direction. For example, in the case of targeting the ground surface of electrolytic abrasive grain polishing that requires removal of a work-affected layer of about 10 μm, in order to continuously perform electrolytic abrasive grain polishing with this electrolytic rough finishing, the electrode tool should be fixed. It is necessary to feed the plate material 1 at the same speed as in the case of electrolytic abrasive grain polishing.

In the electrolytic processing of the surface of the plate material, the plate material 1 is used as a positive electrode and the electrode plate 3 is used as a negative electrode, and an electric current for electrolysis is passed between them to roughen the surface of the plate material at a high speed by electrolytic processing. In the electrolytic processing for this electrolytic rough finishing, a high current density region where the passive film is decomposed and removed by itself is used. The current efficiency at this time is close to 100% (the maximum machining efficiency expected for each material). In this electrolytic grain polishing after rough finishing, a current density of less than 1 A / cm ² which has a current efficiency close to zero is used.

In the electrolytic machining, the feed rate (mm / min) of the electrode tool in the depth direction serves as a measure of machining efficiency, and this is not related to the machining area. In order to obtain a processing speed of 1 mm / min, when processing stainless steel using an aqueous solution of sodium nitrate as an electrolytic solution, Cr elutes with a hexavalent value and is accompanied by anodic reactions such as O ₂ and NO _x generation. It is assumed to be around 90 A / cm ^{2 in the} steady state. The feed rate of 1 mm / min corresponds to the processing rate of removing 10 μm in 0.6 seconds in surface finishing.
Under such processing conditions, the width of the plate material 1 to be polished is 1.5 m
In this case, the current capacity is estimated to be 4860 A.

Assuming that the high-speed electrolytic rough finishing of the above stainless steel plate is applied to the first stage roughing process of the line-type continuous mirror-polishing device by the electrolytic grain polishing method, the maximum feeding speed of the plate material is 6 mm.
/ s. Since the facing time between the work and the electrode for obtaining the processing amount of 10 μm is 0.6 seconds, the width of the electrode plate 3 in the electrode tool 2 may be 3.6 mm.

The current for electrolysis may be a pulse current, and when the required current capacity cannot be obtained, an offline mirror polishing apparatus may be used and the number of passes by the electrolytic tool may be increased.

In the high-speed electrolytic rough finishing method, how much the machining gap is set is an important factor in the system mechanism. In terms of power cost, it is a good idea to reduce the machining gap and machine at a low voltage, but there are variations in the plate thickness, the presence of accidental protrusions, and the plate moving up and down due to feeding. It is dangerous to do. Since it is considered that the limit is about 0.1 mm, it is preferable to set it to about 0.2 mm.

Further, immediately before the plate material 1 is fed to a position facing the electrode plate 3, a sensor is provided which detects the distance between the plate material 1 and the electrode plate 3 so as to detect whether or not the machining gap is always appropriate. It is also possible to monitor whether or not.

The conditions for obtaining a current density of 90 A / cm ² in the 0.2 mm machining gap described above are that the specific conductivity of the electrolyte is 10 V for the inter-electrode voltage.
It is 0.18 S / cm, and even a sodium nitrate aqueous solution can be applied by applying a voltage of 10 V or more. A saline solution is advantageous from the viewpoint of efficiency and economical efficiency, but it is not necessarily advantageous from the viewpoint of balance with the disadvantages such as corrosiveness to surrounding equipment and pits.

The high-speed electrolytic rough finishing method of the present invention can also be applied when the object to be polished is the inner peripheral surface or the outer peripheral surface of the pipe material.

FIG. 2 shows the method of the present invention in which a stainless steel (SUS) pipe material 1 is used.
It shows the state applied to the inner surface of 1. The electrode tool 12 used in this case is attached to the tip of a support rod (not shown) that is equal to or longer than the length of the pipe material 11,
By covering the inner surface of the pipe member 11 with an insulating material 16 except for a portion opposed to the inner surface of the pipe member 11 with a minute gap 14, the electrode plate 13 is formed on the inner peripheral surface of the pipe material 11.
Of the electrode plate 13 and the inner peripheral surface of the tube material 11, the gap 14 between the electrode plate 13 and the inner peripheral surface of the tube material 11, the electrolyte solution is supplied from one end side of the tube material 11 through the flow path 15 in the tube material, and the electrode tool 12 is While relatively moving the tubular material 11 in the axial direction, a current for electrolysis is passed between the tubular material 11 and the electrode plate 13, and the inner surface of the tubular material is roughly finished at a high speed by electrolytic processing.

The electrode tool 12 inserted into the pipe material 11 is such that the peripheral surface of the electrode plate 13 must be opposed to the inner surface of the pipe material 11 via a uniform gap 14, so that the electrode tool or the above-mentioned support rod is provided on the inner surface of the pipe material. It is necessary to provide a guide or the like for contacting and holding the electrode tool 12 at the center of the pipe material 11. Electrode tool 12 and tubing
The relative movement of 11 can hold the electrode tool 12 in a fixed state as shown in the figure and send the pipe material 11 in the direction of arrow B. However, like the case of the plate material described above, it is not limited to this. Absent.

Other electrolysis conditions and the like may be set to be substantially the same as those for the surface finishing of the plate material described above.

The high-speed electrolytic rough finishing method of the present invention is suitable for obtaining a ground surface for super-mirror finishing by electrolytic grain polishing, but is not limited to this, and is made of stainless steel or the like for various purposes. It can be applied when rough finishing the plate material or the inner and outer surfaces of the pipe at high speed.

[Effect of the Invention] According to the method of the present invention described in detail above, the lower surface of a stainless steel material for electrolytic abrasive grain polishing that requires removal of a work-affected layer of about 10 μm, or a material to be polished equivalent thereto The surface of the material, which is a surface and has a large area to the extent that line feeding relative to the electrode tool is required, can be rough-finished with high efficiency by electrolytic machining.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an essential part showing a state where the high-speed electrolytic rough finishing method according to the present invention is applied to a plate material, and FIG. 2 is a half-sectional view of an essential part showing an application state to a pipe material. 1 ・ ・ Plate material, 2,12 ・ ・ Electrode tool, 3,13 ・ ・ Electrode plate, 4,14 ・ ・ Gap, 5,15 ・ ・ Flow passage, 11 ・ ・ Pipe material

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-62-290899 (JP, A) JP-A-62-260100 (JP, A) JP-B 43-22830 (JP, B1) JP-B 57- 47280 (JP, B2)

Claims (2)

[Claims] 1. An electrode plate provided across a polishing width of a plate material to be polished is opposed to the plate material to be polished with a minute gap, and is passed through a flow path inside an electrode tool to which the electrode plate is attached to form an electrode plate. An electrolytic solution is supplied to the gap between the plate material to be polished and the electrode plate is moved relatively along the surface of the plate material, and a work-affected layer of about 10 μm on the surface of the plate material is provided between the plate material and the electrode plate. A high-speed electrolytic rough-finishing method characterized in that a plate material surface is rough-finished at a high speed by electrolytic machining by passing an electric current for the electrolytic processing to be removed. 2. An electrode plate is opposed to an inner peripheral surface or an outer peripheral surface of a pipe material to be polished with a minute gap, and an electrolytic solution is supplied to a gap between the electrode plate and the pipe material to be polished, and the electrode is used. While relatively moving the plate in the axial direction of the pipe material, an electric current is passed between the pipe material and the electrode plate to remove a process-altered layer of approximately 10 μm on the surface of the pipe material, and an electric current is applied to electrolyze the inner or outer surface of the pipe material. A high-speed electrolytic rough finishing method characterized by high-speed rough finishing by processing.