JP2011231354A - Electrolytic polishing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve reduction in polishing time and smoothing of a polished surface by efficiently polishing the surface of a member to be measured (a member to be polished).SOLUTION: In the lower end edge of a cylindrical container 11 to the inside of which is fed an electrolyte solution 18, a seal 12 is arranged to prevent leakage. A motor 14 rotates a sliding member 16 to rub the surface of an electrolytic polishing region 1a, and a stirring member 17 stirs the electrolyte solution 18, which is energized by a direct current power source 19. Rubbing with a sliding member 16 can effectively remove a nonconducting film to equally feed the electrolyte solution 18 to the electrolytic polishing region 1a, thus being capable of achieving improvement in the speed of electrolytic polishing and smoothing of a polished surface.

Description

  The present invention relates to an electrolytic polishing apparatus, which is devised so that a member to be measured (member to be polished) can be efficiently polished.

  Residual stress generated by processing or welding a metal part may cause cracking or the like. Further, when the residual stress becomes a compressive stress, fatigue fracture is suppressed or wear resistance is improved, so that it may be positively applied depending on mechanical parts.

As a method for inspecting the magnitude and depth of such residual stress in a nondestructive manner, there is an X-ray stress measurement method.
The X-ray stress measurement method means that when a stress acts on the member to be measured, the crystal is elastically deformed and appears as contraction (in the case of compressive stress) or expansion (in the case of tensile stress) of the crystal lattice plane interval. This is a method of measuring residual stress by measuring the lattice spacing using X-ray diffraction.

  When carrying out the above X-ray stress measurement method, the surface of the member to be measured needs to be smooth. Further, in order to measure the residual stress in each part in the depth direction, it is necessary to polish the member to be measured to the measurement depth and perform X-ray stress measurement at the depth position.

  Here, a conventional method of smoothing the surface of the member to be measured or polishing to a predetermined depth for measuring the X-ray stress will be described with reference to FIGS.

  As shown in FIGS. 3 and 4, a dish-shaped masking member 2 having a flat bottom surface formed of gum tape or the like is attached to the surface of a member to be measured (a member to be polished) 1 made of metal. A hole 2a having a diameter of, for example, 8 to 10 mm is formed on the bottom surface of the masking member 2, and the surface of the member 1 to be measured is exposed at the hole 2a.

The electrolytic solution 3 is placed inside the masking member 2, and a positive voltage (+ voltage) is applied to the member 1 to be measured by the DC power supply 4, and a negative voltage (−voltage) is applied to the tweezers 5.
As the electrolytic solution 3, for example, an ammonium chloride supersaturated aqueous solution or a mixed solution of hydrochloric acid and alcohol is employed.

The operator wears rubber gloves, grips the cotton 6 with the tweezers 5, and rubs the surface of the member 1 to be measured exposed from the hole 2 a with the cotton 6 while immersing the tweezers 5 in the electrolytic solution 3.
In this way, the tweezers 5 are energized by immersing them in the electrolytic solution 3, and the member 1 to be measured exposed from the hole 2a is electropolished. Further, by rubbing the surface of the member 1 to be measured exposed from the hole 2a with the cotton 6, the nonconductive film generated along with the electropolishing can be removed, and the continuous voltage application is ensured to promote the electropolishing. ing.

  When the surface of the portion exposed from the hole 2a of the member to be measured (member to be polished) 1 is electrolytically polished by the above operation, the electrolytic solution 3 is discharged from the masking member 2, and the masking member 2 is further removed from the member 1 to be measured. Then, after cleaning the surface of the member 1 to be measured, X-ray stress measurement is performed on the electropolished portion of the surface of the member 1 to be measured.

Thereafter, the state as shown in FIGS. 3 and 4 is set again, and the hole 2a of the new masking member 2 of this time is aligned with the portion of the surface of the member 1 to be measured that has been previously electropolished. In the same manner as the previous time, the same portion is electropolished and deepened to a predetermined depth (for example, 100 μm or 0.25 mm).
When the portion of the member to be measured 1 exposed from the hole 2a becomes deeper by electrolytic polishing and the depth measured by another apparatus reaches a predetermined depth, the electrolytic solution 3 is discharged from the masking member 2, and further the masking member 2 is removed from the member 1 to be measured, and the surface of the member 1 to be measured is washed, and then the X-ray stress measurement is performed on the electropolished portion of the surface of the member 1 to be measured.

  Thereafter, the same operation is repeated, and X-ray stress measurement is performed at a plurality of depth positions having different depth directions.

JP 7-204935 A JP-A-2-301600 JP 7-248305 A

  By the way, in the prior art shown in FIGS. 3 and 4, since the tweezers 5 are gripped by a human hand and the surface of the member 1 to be measured is rubbed with the cotton 6 gripped at the tip of the tweezers 5, the work is troublesome and causes a lot of fatigue. It was.

  The polishing amount is estimated based on the current value and the energization time. However, since the operator holds the tweezers 5 and works, the energization amount is not constant and the removal of the non-conductive film is not constant or uniform. As estimated, the polishing amount may not be obtained or the polished surface may not be flat. In this case, in order to polish to a predetermined depth, it may be necessary to perform the setting state shown in FIGS. 3 and 4 a plurality of times.

  Furthermore, in order to perform the above-described electrolytic polishing, the member to be measured 1 must be carried into the test chamber in which the DC power supply 4 is installed and the test must be performed, and the electrolytic polishing cannot be easily performed. .

  An object of the present invention is to provide an electropolishing apparatus that eliminates human work as much as possible and enables efficient polishing (reduction of polishing time and smoothing of a polished surface).

The configuration of the present invention for solving the above problems is as follows.
A cylindrical shape in which a sealing material is applied to one opening edge, the sealing material is disposed on the surface of the member to be polished in contact with the surface of the member to be polished, and an electrolyte is injected into the internal space A container,
A sliding member disposed inside the cylindrical container and rubbing the surface of the member to be polished;
It is installed in the said cylindrical container, It has a sliding means to slide the said sliding member, It is characterized by the above-mentioned.
In this case,
The sliding means comprises a motor and a rotating shaft that transmits the rotational force of the motor to the sliding member,
The rotating shaft is provided with a stirring member for stirring the electrolyte solution,
The apparatus further includes a direct current power source for applying a positive voltage to the member to be polished and applying a negative voltage to the electrolytic solution.

  According to the present invention, since the surface of the member to be measured (the member to be polished) is rubbed by the sliding member by the sliding member, the non-conductive film on the polishing surface is removed, stable power feeding is possible, and efficient Polishing (shortening the polishing time and smoothing the polishing surface) is possible, and the burden on the operator can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS The block diagram which shows the electropolishing apparatus which concerns on Example 1 of this invention. The block diagram which shows the etching apparatus which concerns on Example 2 of this invention. The perspective view which shows the masking member used for the conventional electrolytic polishing method. The block diagram which shows the conventional electropolishing apparatus.

  Hereinafter, embodiments of the present invention will be described in detail based on examples.

  FIG. 1 shows an electropolishing apparatus 10 according to Embodiment 1 of the present invention. The electropolishing apparatus 10 is an apparatus for electropolishing an electropolishing region 1a of a member to be measured (a member to be polished) 1 made of metal.

The cylindrical container 11 of the electropolishing apparatus 10 is arranged in a standing state on the surface of the member 1 to be measured, and one opening edge of the cylindrical container 11 (lower opening edge in FIG. 1). The seal material 12 is disposed on the surface.
As the sealing material 12, rubber material, oil clay, or the like can be used. Since the sealing material 12 is provided, the sealing material 12 is measured even when the surface of the measured member 1 is not flat. Since the surface of the member 1 is in close contact with the surface of the member 1, it is possible to prevent the leakage of the electrolyte described later.

A lid member 13 is disposed on the other end surface of the cylindrical container 11 (upper end surface in FIG. 1), and a motor 14 is disposed on the lid member 13. The rotating shaft 15 passes through the lid member 13 and is connected to the motor shaft of the motor 14. A sliding member 16 such as sponge or heat-resistant cotton is attached to the lower end of the rotating shaft 15.
For this reason, the sliding member 16 is disposed inside the cylindrical container 11, and the rotation of the motor 14 is transmitted via the rotating shaft 15, whereby the sliding member 16 rotates and the device under measurement is measured. Of the surface of the member 1, a portion exposed inside the cylindrical container 11 (the surface of the electropolishing region 1a) is rubbed.
The sliding member 15 is made of a material that is soft enough not to scratch the surface of the member to be measured (the member to be polished) 1 by sliding and is impregnated with an electrolyte described later. Is adopted.

Further, a propeller-like or screw-like stirring member 17 is attached to the rotating shaft 15.
When electrolytic polishing is performed, an electrolytic solution 18 is injected into the cylindrical container 11. As the electrolytic solution 18, for example, an ammonium chloride supersaturated aqueous solution or a mixed solution of hydrochloric acid and alcohol is used.

  The DC power source 19 applies a positive voltage (+ voltage) to the member 1 to be measured, and applies a negative voltage (− voltage) to the electrolytic solution 18.

When performing electropolishing, the motor 14 rotates the sliding member 16 to rub against the surface of the electropolishing region 1a to remove the non-conductive film continuously and effectively. The surface of the polishing region 1a is electropolished. In addition, the electrolyte member 18 is stirred by the stirring member 17 to make the concentration uniform.
The amount of electrolytic polishing can be estimated from the current value and the polishing time (current conduction time). At this time,
(1) The sliding member 16 is rotated and the surface of the electropolishing region 1a is rubbed to remove the nonconductive film continuously and effectively.
(2) The electrolyte member 18 is stirred by the stirring member 17 to make the concentration uniform;
Thus, the amount of electropolishing by the above estimation becomes more accurate. Moreover, since the electrolytic solution 18 contacts the surface of the electropolishing region 1a evenly, the polishing surface becomes flat (the depth is constant).

Thus, since the non-conductive film generated in the electropolishing region 1a is reliably removed, stable power feeding is possible, and efficient polishing, that is, shortening the polishing time and smoothing the polishing surface can be achieved. It becomes possible.
In addition, polishing can be performed automatically, and operator fatigue is reduced.

  When the surface of the electropolishing region 1a of the member 1 to be measured is electrolytically polished by the above operation, the electrolytic solution 18 is discharged from the inside of the cylindrical container 11, and the electropolishing apparatus 10 including the cylindrical container 11 is further measured After removing from 1 and cleaning the surface of the member 1 to be measured, X-ray stress measurement is performed on the surface of the electropolished region 1a that has been electropolished.

After the above X-ray stress measurement, the state as shown in FIG. 1 is set again, and the electrolytic solution polishing region 1a of the member 1 to be measured faces the inside of the cylindrical container 11, The same portion is electropolished and deepened to a predetermined depth (for example, 100 μm or 0.25 mm).
When the electropolishing region 1a of the member 1 to be measured is deepened by electropolishing and reaches a predetermined depth, the electrolytic solution 18 is discharged from the inside of the cylindrical container 11, and the electropolishing apparatus 10 including the cylindrical container 11 is further removed. After removing from the member 1 to be measured and cleaning the surface of the member 1 to be measured, X-ray stress measurement is performed on the surface of the electropolished region 1a that has been electropolished.
Thereafter, the same operation is repeated, and X-ray stress measurement is performed at a plurality of depth positions having different depth directions.
In this way, X-ray stress measurement can be performed at each position in the depth direction.

  In addition, the portable type electropolishing apparatus 10 can be held where the member to be measured 1 exists, and electropolishing and X-ray stress measurement can be performed at the site.

In this Example 1, the member to be measured (member to be polished) 1 is a SUS316 block material, the inside diameter of the cylindrical container 11 is 8 mm, the applied voltage is 10 V, the electrolytic solution 18 is an ammonium chloride supersaturated aqueous solution, and polishing is performed. The polishing state when operated empirically with a time of 2 minutes was as follows.
The amount of electropolishing in the depth direction is 2.53 mm.
The surface roughness of the polished surface was an arithmetic average roughness Ra of 0.68 [μm] and a maximum height roughness Rz of 3.8 [μm].

Incidentally, the polishing state when the electrolyte solution 18 was only stirred without being rubbed by the sliding member 16 and operated in an empirical manner under the same conditions as in the above example was as follows.
The depth of electropolishing in the depth direction is 0.06 mm.
As for the surface roughness of the polished surface, the arithmetic average roughness Ra was 0.94 [μm], and the maximum height roughness Rz was 5.3 [μm].

Further, the polishing state in the case of empirically operating without rubbing by the sliding member 16 and without stirring the electrolyte solution 18 under the same conditions as in the above example was as follows.
The amount of electropolishing in the depth direction is 0.03 mm.
The surface roughness of the polished surface was an arithmetic average roughness Ra of 1.39 [μm] and a maximum height roughness Rz of 7.0 [μm].

  As can be seen from the above-described empirical operating state, in Example 1, the nonconductive film is effective by rubbing the surface of the electropolishing region 1a with the sliding member 16 and stirring the electrolytic solution 18 with the stirring member 17. As a result, the power supply is stabilized and the concentration of the electrolytic solution 18 becomes uniform, and a large polishing amount can be obtained. It can also be seen that the surface roughness is the smallest.

In the above example, the sliding member 16 is rotated by the motor 14, but it is also possible to employ another mechanical mechanism to reciprocate the sliding member 16.
In addition, an electrolytic solution storage tank and an electrolytic solution supply / discharge device having a mechanism for supplying / discharging the electrolytic solution are attached to the cylindrical container 11, and when polishing, the electrolytic solution supply / discharge device is connected to the cylindrical container. It is also possible to supply the electrolytic solution 18 into the inside 11 and to suck the electrolytic solution 18 in the cylindrical container 11 toward the electrolytic solution supply / discharge device when polishing is finished.

Next, an etching apparatus 100 according to a second embodiment which is an application example of the present invention will be described with reference to FIG.
The premise of using this etching apparatus 100 will be described first.

For example, when a part of the blade is deformed in the manufacturing process of the impeller, the gas turbine may be heated and shaped. When such shaping is performed, in order to confirm the presence or absence (range) of sensitization by heating, it is necessary to perform a number of sump tissue tests on the part.
One method for detecting the degree of sensitization of a metal material (for example, stainless steel) is an oxalic acid etching test method (JIS G 0571).
In this test method, the test solution temperature is set to 20 to 50 ° C., the test solution is set to 10% oxalic acid test solution, the test time is set to 1 A / 90 sec / 1 cm ² , and the test portion is etched. A sump tissue test is being conducted.

Returning to FIG. 2, the etching apparatus 100 will be described. The etching apparatus 100 is an apparatus that etches the etching region 101 a of the sample 101.
The cylindrical container 102 of the etching apparatus 100 is arranged in a standing state on the surface of the sample 101, and one opening edge (lower opening edge in FIG. 2) of the cylindrical container 102 includes A sealing material 103 is disposed.
As the sealing material 103, rubber material, oil clay, or the like can be used. Since the sealing material 103 is provided, the sealing material 103 is the surface of the sample 101 even when the surface of the sample 101 is not flat. Since it is in close contact with the substrate, it is possible to prevent leakage of an etching solution described later.

Etching solution supply pipes 104a and 104b are connected to the other end face side (the upper end face side in FIG. 2) of the cylindrical container 102, and a 10% oxalic acid solution is passed through the etching solution supply pipes 104a and 104b. An etching solution 105 is supplied into the cylindrical container 102.
Further, an etching solution discharge pipe 106 is disposed at the center of the cylindrical container 102, and the etching solution 105 stored in the cylindrical container 102 is discharged to the outside of the cylindrical container 102.

  A propeller-like or screw-like rotating member 107 is disposed below the etching solution discharge pipe 106, and this rotating member 107 is rotated by a rotating mechanism (not shown). When the rotating member 107 rotates, the etching solution 105 flows toward the portion of the surface of the sample 101 that faces the cylindrical container 102, that is, the surface of the etching region 101a.

  The controller 108 detects the temperature of the etching solution 105 while energizing the sample 101 and measures the time during which the etching region 101 a is exposed to the etching solution 105. Thereby, the surface of the etching region 101a is etched. In addition, since the etching solution 105 is caused to flow toward the etching region by the rotation of the rotating member 107, good etching can be performed.

Etching can be performed easily and reliably by attaching the etching apparatus 100 to the portion of the blade that is the inspection object.
When the etching is completed, the etching apparatus 100 is removed, and the part is washed, and then a sump structure test is performed.

1 member to be measured (member to be polished)
DESCRIPTION OF SYMBOLS 2 Masking member 3 Electrolyte solution 4 DC power supply 5 Tweezers 6 Cotton 10 Electropolishing apparatus 11 Cylindrical container 12 Sealing material 13 Cover material 14 Motor 15 Rotating shaft 16 Sliding member 17 Stirring member 18 Electrolytic solution 19 DC power supply 100 Etching device 101 Sample 101a Etching area 102 Cylindrical container 103 Sealing material 104a, 104b Etching solution supply pipe 105 Etching solution 106 Etching solution discharge pipe 107 Rotating member 108 Control unit

Claims (4)

A cylindrical shape in which a sealing material is applied to one opening edge, the sealing material is disposed on the surface of the member to be polished in contact with the surface of the member to be polished, and an electrolyte is injected into the internal space A container,
A sliding member disposed inside the cylindrical container and rubbing the surface of the member to be polished;
A sliding means installed in the cylindrical container and sliding the sliding member;
An electropolishing apparatus comprising: In claim 1,
The electropolishing apparatus, wherein the sliding means includes a motor and a rotating shaft that transmits a rotational force of the motor to the sliding member. In claim 2,
An electropolishing apparatus, wherein a stirring member for stirring the electrolytic solution is attached to the rotating shaft. In any one of Claims 1 thru | or 3,
An electropolishing apparatus further comprising a direct current power source for applying a positive voltage to the member to be polished and applying a negative voltage to the electrolytic solution.

Images