JP2010234499A - Apparatus and method for forming coating film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for forming a coating film in which the time for attaching/detaching a workpiece to/from a workpiece holding jig and time for surface treatment of the workpiece are shortened and formation of the coating film onto a surface of the workpiece is efficiently performed by continuously performing the surface treatment of the workpiece and the formation of the coating film onto the surface of the workpiece in one process with one device. <P>SOLUTION: In the apparatus for forming the coating film, the surface treatment is applied to the workpiece supported in a treatment chamber to impart compressive residual stress to the workpiece and the coating film is formed on the workpiece. The apparatus includes a surface treatment mechanism movable along the workpiece to spray electrolytic solution containing projection material to the surface of the workpiece with high pressure and impart the compressive residual stress, and a coating film forming mechanism movable along the workpiece to spray the electrolytic solution to the surface of the workpiece with low pressure and form the coating film. The workpiece is electrically connected to a power source in a positive electrode side, and an electrode of the coating film forming mechanism is electrically connected to the power source in a negative electrode side. Respective jet nozzles of the surface treatment mechanism and jet nozzles of the coating film forming mechanism are concentrically arranged. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a film forming apparatus and a film forming method for performing a surface treatment for applying a compressive residual stress to a work (workpiece) such as a gear and forming a film.

  For example, for workpieces that move in contact with the surface of the other metal member, such as gears, bearings, various pins, pivots, pistons, cylinders, etc., in the presence of lubricating oil, abnormal wear and seizure Is a problem. As a means to alleviate this problem, a method is known in which residual compressive stress is introduced by performing peening treatment such as shot peening to improve the fatigue strength of the workpiece, and the workpiece (especially the sliding surface). There is known a method of forming a sulfide-based solid lubricating film such as iron sulfide-based, molybdenum sulfide-based, or tungsten sulfide-based on the surface thereof.

  Patent Documents 1 and 2 disclose a shot peening method for projecting a fine shot on a work surface to increase the material strength as a method for improving the metal material fatigue strength of the work. According to this peening method, generation of unprocessed areas can be prevented and efficient peening processing can be performed, and the quality of the workpiece can be improved. Further, Patent Document 3 describes a processing method and a processing apparatus that can perform cleaning along with surface treatment of a workpiece.

  Patent Documents 4 and 5 disclose a sliding member that has undergone a sulfurization treatment such as forming a sulfide-based solid lubricating film on the sliding surface, and a method for manufacturing the same. According to the invention described in Patent Document 1, there is provided a sliding member having good workability and excellent seizure resistance having an inexpensive sulfide-based solid lubricating film.

JP-A-8-155836 JP 2002-326161 A JP 2003-62492 A JP 2001-115177 A Japanese Patent Laid-Open No. 11-302897

  However, conventionally, the step of performing the surface treatment of the workpiece described in Patent Literatures 1 to 3 and the step of forming a sulfide-based solid lubricant film on the workpiece sliding surface described in Patent Literatures 4 and 5 It was performed as a separate process, and the apparatus and workpiece holding jig for performing each process were performed with different ones. In this case, the surface treatment of the workpiece and the step of forming the sulfide-based solid lubricating film cannot be performed continuously, and the processing time is long due to the individual time required to attach and detach the workpiece to and from the workpiece holding jig. There was a problem of time. Furthermore, since the apparatus for performing each process and the work holding jig are separate, there is a problem that the installation space and equipment cost of these apparatuses and the work holding jig cost increase.

  In addition, since there are various types of workpieces having sliding surfaces, as described above, when using a plurality of processes / devices, it takes time and effort to change the workpiece holding jig according to the type of workpiece. Efficiency and work costs were issues.

  Therefore, an object of the present invention is to perform workpiece surface treatment and formation of a film on the workpiece surface with a single apparatus, by continuously performing one step or a plurality of steps, thereby reducing the workpiece attachment / detachment time with respect to the workpiece holding jig. The object is to reduce the processing time for surface treatment, etc., and to efficiently perform surface treatment of the workpiece and film formation on the workpiece surface.

  According to the present invention, there is provided a film forming apparatus that performs a surface treatment for imparting compressive residual stress to a work supported in a processing chamber, and forms a film on the work. A surface treatment mechanism that is sprayed at a high pressure to impart compressive residual stress, and is movable along the workpiece, and a coating that is movable along the workpiece is formed by spraying an electrolyte on the surface of the workpiece at a low pressure. A work mechanism, the work is electrically connected to the anode side of the power supply, the electrode of the film forming mechanism is electrically connected to the cathode side of the power supply, the spray port of the surface treatment mechanism and the film formation mechanism A film forming apparatus is provided in which the nozzles are arranged concentrically.

  The electrolytic solution containing the projection material and the electrolytic solution are stored separately in a storage portion at the lower part of the processing chamber, and the electrolytic solution containing the projection material and the electrolytic solution are disposed around the electrolytic solution containing the projection material in the coaxial direction. The electrolytic solution is ejected so as to surround it, the electrolytic solution containing a projection material is injected at 0.1 MPa to 300 MPa, and the electrolytic solution is injected at 0.01 MPa to 1 MPa. Further, the surface treatment mechanism and the film forming mechanism move integrally, the workpiece is made of iron or an iron alloy, and the film formed by the film forming mechanism is a sulfide-based solid lubricating film.

  According to another aspect of the present invention, there is provided a film forming method for forming a film on a workpiece, which is positively charged and sprays an electrolytic solution containing a projectile material onto the rotating workpiece at a high pressure, and the projection A film forming method is provided in which a negatively charged electrolytic solution is sprayed onto the workpiece at a low pressure concentrically with a material-containing electrolytic solution.

  The electrolytic solution containing the projecting material and the electrolytic solution are ejected in a coaxial direction so that the electrolytic solution surrounds the electrolytic solution containing the projecting material, and the electrolytic solution containing the projecting material is injected at 0.1 MPa to 300 MPa. The electrolyte is injected at 0.01 MPa to 1 MPa. The workpiece is made of iron or an iron alloy, and the film formed by the film forming mechanism is a sulfide-based solid lubricating film.

  According to the present invention, the surface treatment of a workpiece and the formation of a film on the workpiece surface can be performed with one apparatus, and by continuously performing one process or a plurality of processes, Processing time such as surface treatment can be shortened, and surface treatment of the workpiece and film formation on the workpiece surface can be efficiently performed.

It is sectional drawing which looked at the film formation apparatus 1 from the side.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a sectional view of a film forming apparatus 1 according to the present invention as seen from the side. The film forming apparatus 1 includes an upper processing chamber 10, a storage portion 12 that stores a projection material-containing electrolytic solution A and a storage portion 13 that stores an electrolytic solution B, which are installed in the lower portion of the processing chamber 10. Moreover, the storage part 12 and the storage part 13 are partitioned off by the partition plate 11, and the electrolyte solution can overflow only from the storage part 13 to the storage part 12. Here, the processing chamber 10 and the storage containers 12 and 13 are coupled via an electrical insulator 14. Inside the processing chamber 10 is placed a mounting table 17 on which a workpiece holding jig 16 with a workpiece 15 attached is placed, and a plurality of workpieces 15 such as iron or iron alloy gears are vertically (in the vertical direction in FIG. 1). It is attached to the work holding jig 16 and installed on the mounting table 17. Here, the plurality of workpieces 15 are deposited in the processing chamber 10 so that the film formation target surface, which is the sliding surface of the workpiece 15, becomes the outer peripheral surface. Further, the mounting table 17 is provided with a rotation mechanism (not shown) that is driven by a motor or the like, and the plurality of workpieces 15 are rotatable in the horizontal direction as the mounting table 17 rotates. The mounting table 17 and the workpiece 15 may be rotated at any time, but more preferably, the rotating operation is performed only during the surface treatment and the film formation.

  A surface treatment mechanism 20 and a film formation mechanism 30 are disposed inside the processing chamber 10. As shown in FIG. 1, the surface treatment mechanism 20 is disposed inside the film formation mechanism 30 so as to be surrounded by the film formation mechanism 30. Here, the surface treatment mechanism 20 and the film formation mechanism 30 can be moved up and down in the processing chamber 10 by a lifting mechanism (not shown), and the lifting and lowering is performed integrally. Further, the surface treatment mechanism 20 is provided with an injection port 21, and the film formation mechanism 30 is provided with an injection port 31. The injection port 21 and the injection port 31 are always opposed to the outer peripheral surface of the workpiece 15, and The surface treatment mechanism 20 and the film forming mechanism 30 are moved up and down within a range where the injection port 21 and the injection port 31 face the outer peripheral surface of the workpiece 15.

  The surface treatment mechanism 20 communicates with the storage unit 13 disposed below the processing chamber 10 and storing the electrolytic solution B through the communication path 22 and the mixing mechanism 25. Here, the high-pressure pump 23 is attached to the communication path 22, and the electrolytic solution B is introduced from the storage unit 13 to the mixing mechanism 25 provided in the surface treatment mechanism 20 by the operation of the high-pressure pump 23. Further, the surface treatment mechanism 20 communicates with the storage unit 12 disposed below the processing chamber 10 and storing the electrolytic solution A containing the projection material through the communication path 26 and the mixing mechanism 25. A low-pressure pump 27 is attached to the communication path 26, and the operation of the low-pressure pump 27 introduces the projection material-containing electrolyte A from the reservoir 12 into the mixing mechanism 25 provided in the surface treatment mechanism 20. In the mixing mechanism 25, the electrolytic solution A and the electrolytic solution B containing the projecting material are mixed, and the mixed electrolytic solution (that is, the electrolytic solution containing the projecting material) obtained by mixing the electrolytic solution A and the electrolytic solution B containing the projecting material is the surface treatment mechanism 20. The structure is such that high pressure is injected from the injection port 21 to the work 15. As described above, since the injection port 21 faces the outer peripheral surface of the work 15, the mixed electrolytic solution (that is, the electrolytic solution containing a projection material) is injected to the outer peripheral surface of the work 15 at a high pressure. Then, after being injected onto the outer peripheral surface of the work 15, the mixed electrolyte falls and is collected in the storage unit 12.

  A cyclone 40 is connected to the reservoir 12 and the communication path 28, and a reservoir 41 is connected to the cyclone 40. Here, the cyclone 40 is a device for dividing the projection material contained in the electrolyte solution A containing the projection material in the reservoir 12. When the electrolytic solution A containing the projecting material is sprayed onto the work 15, the projecting material collides with the work 15, so that a phenomenon such as a decrease in the particle size of the projecting material or a breakage of the projecting material occurs. The projection material having such a defective shape is removed in the cyclone 40, and only the reusable electrolyte A containing the projection material is returned to the storage unit 12 and stored. In addition, other electrolyte solutions A (basically electrolyte solution A containing no projection material, but also electrolyte solution A containing a projection material with a smaller particle size or a projection material that cannot be crushed are included. Is stored in the storage unit 41.

  On the other hand, the film forming mechanism 30 is disposed below the processing chamber 10 via the communication path 32 and communicates with the storage unit 13 in which the electrolytic solution B is stored. Here, a low pressure pump 33 is attached to the communication path 32, and the electrolytic solution B is introduced from the reservoir 13 to the film forming mechanism 30 by the operation of the low pressure pump 33, and the electrolytic solution B is injected from the injection port 31 of the film forming mechanism 30. Is configured to be injected. Since the injection port 31 faces the outer peripheral surface of the work 15, the electrolytic solution B is injected onto the outer peripheral surface of the work 15 at a low pressure. Then, the electrolytic solution B is sprayed on the outer peripheral surface of the work 15 and then falls and is collected in the storage unit 12.

A filter 35 is installed in the communication path 32. The filter 35 removes the projection material mixed in the electrolytic solution B in the storage unit 13, falling particles (such as burrs) from the work 15 generated during the surface treatment, insoluble sludge generated by the film formation reaction, and the like. Is attached. In the filter 35, the falling particles and the insoluble stats are filtered and removed from the electrolytic solution B, thereby preventing the film forming mechanism 30 from being damaged or worn out.

The discharge pressure of the high-pressure pump 23 is 0.1 MPa or more (high-pressure pumps up to several hundred MPa can be used, but the normal range is about 5 MPa to 300 MPa), and more preferably 25 MPa to 100 MPa. Further, the discharge pressure of the low-pressure pump 27 is 0.05 MPa or more (a low-pressure pump up to several MPa can be used, but about 0.1 MPa to 0.5 MPa is a normal range), preferably 0.05 MPa to 0.00. 35 MPa. The discharge pressure of the low-pressure pump 33 is 0.01 MPa or more (a low-pressure pump up to several MPa can be used, but about 0.1 MPa to 1 MPa is a normal range), preferably 0.15 MPa to 0.5 MPa. Here, the discharge pressures of the high-pressure pump 23 and the low-pressure pump 33 are the compressive residual stress applied to the surface of the work 15 in accordance with the material and pretreatment of the work 15 to be processed and the use conditions within the above-described pressure range. It is desirable to select a discharge pressure that suitably obtains the distribution.

  In addition, an electrode 60 is provided on the inner periphery of the film forming mechanism 30, and the electrode 60 is electrically connected to the cathode side of a power source 62, for example, a DC power source provided outside the processing chamber 10. Therefore, the electrolytic solution B introduced into the film forming mechanism 30 by the operation of the power supply 62 is negatively charged. On the other hand, the work holding jig 16 is electrically connected to the anode side of the power supply 62, and the work 15 held on the work holding jig 16 is positively charged by the operation of the power supply 62.

  The reservoir 12 stores a projection material-containing electrolyte A containing 1 to 50 vol% of a projection material in an aqueous solution in which one or more of thiocyanate or thiosulfate of an alkali metal or alkaline earth metal is dissolved. The Examples of the type of the projecting material include alumina having a particle size of 5 to 300 μm that does not react with the electrolytic solution, and the compressive residual stress applied to the surface of the work 15 corresponding to the material and pretreatment and use conditions of the work 15 and its A projection material suitable for obtaining the distribution may be selected. Further, the storage unit 13 is adjacent to the storage unit 12 with the partition plate 11 interposed therebetween, and the storage unit 13 includes one or two kinds of alkali metal or alkaline earth metal thiocyanate or thiosulfate that does not include a projection material. The electrolytic solution B which is an aqueous solution in which the above is dissolved is stored.

  On the other hand, the storage part 41 and the storage part 13 are connected via the supply path 65, and the electrolyte solution which does not contain the projection material stored by the storage part 41 is supplied to the storage part 13. Here, a Ph meter, an electromagnetic concentration meter, a thermometer, a filter, and the like (not shown) are installed in the storage unit 41, and it is determined that the storage unit 13 can be reused by these Ph meter, electromagnetic concentration meter, and thermometer. Supply the electrolyte. Moreover, a projection material is directly injected | thrown-in to the storage part 12, is mixed with electrolyte solution in the storage part 12, and becomes the electrolyte solution A containing a projection material.

  In the film forming apparatus 1 configured as described above, surface treatment and film formation on the workpiece 15 are performed. Since the projection material-containing electrolyte A stored in the storage unit 12 contains the projection material, it is not suitable for pressurization up to a discharge pressure suitable for surface treatment using the high-pressure pump 23. Therefore, since the projecting material is not contained in the electrolytic solution B introduced into the mixing mechanism 25 through the communication path 26 by the operation of the low-pressure pump 27 and stored in the storage unit 13, it is suitable for surface treatment using the high-pressure pump 23. It is possible to pressurize to a proper discharge pressure and is introduced into the mixing mechanism 25 through the communication path 22 by the operation of the high-pressure pump 23. Then, a mixed electrolytic solution obtained by mixing the electrolytic solution A and the electrolytic solution B (that is, the electrolytic solution containing the projecting material) is injected from the injection port 21 to the work 15 at a high pressure. By the high-pressure injection of the mixed electrolytic solution onto the outer peripheral surface (sliding surface) of the work 15, a conventionally known peening process for imparting compressive residual stress is performed, and the fatigue strength of the work 15 is improved. Here, since the work 15 rotates in the horizontal direction (left and right direction in FIG. 1), the injection of the mixed electrolyte from the injection port 21 is performed uniformly on the outer peripheral surface of the work 15. Furthermore, since the surface treatment mechanism 20 injects the mixed electrolyte solution onto the work 15 while moving up and down so that the injection port 21 extends along the outer peripheral surface of the work 15, the mixed electrolyte solution is equally applied to any of the plurality of stacked workpieces 15. Be injected. Therefore, by rotating the workpiece 15 and raising / lowering the surface treatment mechanism 20, all the outer peripheral surfaces of the plurality of deposited workpieces 15 are uniformly surface-treated.

  Further, the electrolytic solution B stored in the storage unit 13 is introduced into the film forming mechanism 30 through the communication path 32 by the operation of the low pressure pump 33, and is injected from the injection port 31 to the workpiece 15 at a low pressure. Here, as described above, the workpiece 15 is positively charged and the electrode 60 is negatively charged. Therefore, a film is formed on the outer peripheral surface (sliding surface) of the work 15 by an electrochemical reaction using the work 15 of the electrolytic solution B as an anode. Here, a room temperature sulfidation process as an example of the film formation will be described below.

  The room temperature sulfidation process is a process for forming a sulfide-based solid lubricating film on the workpiece sliding surface described in Patent Documents 4 and 5, and the article to be processed (work) in a room temperature solution of an alkali metal salt containing sulfur. Is a room temperature sulfidation treatment technique in which an iron sulfide layer having a thickness of several μm is formed on the surface of an article to be treated by an electrochemical reaction using the article to be treated as an anode. As the electrolytic solution for immersing the article to be treated, an aqueous solution in which one or more of thiocyanate or thiosulfate of alkali metal or alkaline earth metal is dissolved is mainly used. An iron sulfide film (sulfide-based solid lubricant film) can be formed on the surface of iron or an iron alloy by performing a room temperature sulfidation process using these electrolytes. In addition, since the room temperature sulfidation process is a room temperature treatment, the compressive residual stress obtained by quenching hardness, shot peening, etc. is maintained, and distortion of the article to be treated due to heat can be prevented. The hardness etc. are secured. That is, the iron sulfide film can be formed while maintaining the compressive residual stress cured by the surface treatment by the spraying of the projection material of the present invention.

  In the film forming apparatus 1 according to the present embodiment using the room temperature sulfidation process, as the electrolytic solution A and the electrolytic solution B containing the projection material, one or two of thiocyanate or thiosulfate of alkali metal or alkaline earth metal is used. A coating made of iron sulfide can be formed on the outer peripheral surface of the work 15 by injecting the electrolytic solution B onto the work 15 made of iron, an iron alloy or the like using an aqueous solution in which seeds or more are dissolved. By forming a film on the workpiece 15, problems such as seizure of the workpiece on the sliding surface and abnormal wear are solved.

  That is, peening treatment is performed on the outer peripheral surface (sliding surface) of the workpiece 15 by high-pressure injection of the mixed electrolyte from the surface treatment mechanism 20, thereby improving fatigue strength. At the same time, a film is formed on the outer peripheral surface (sliding surface) of the work 15 by low-pressure injection of the electrolytic solution B from the film forming mechanism 30. According to the film forming apparatus 1 according to the present embodiment, the peening process and the film formation can be performed continuously almost simultaneously, and the outer peripheral surfaces (sliding surfaces) of the plurality of workpieces 15 can be uniformly formed. Can be done. Conventionally, peening processing such as shot peening and film formation have been performed by different apparatuses and processes. However, by using the film forming apparatus 1 according to the present embodiment, surface treatment (peening processing) of the work 15 and work The film formation on the surface 15 is continuously performed with one process and one apparatus, and the work 15 can be attached to and detached from the work holding jig 16 and the processing time such as the surface treatment can be shortened. Surface treatment and film formation on the surface of the workpiece 15 can be performed. In addition, the said peening process and film formation can also be sequentially performed using the apparatus of this invention.

  As mentioned above, although an example of embodiment of this invention was demonstrated, this invention is not limited to the form of illustration. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the idea described in the claims, and these naturally belong to the technical scope of the present invention. It is understood.

  In the above embodiment, the workpiece is made of iron or an iron alloy. However, the present invention is not limited to this, and any steel type that can form a film using the above-described room temperature sulfidation process may be used. For example, martensitic steel types such as SCM, SCr, SK, SUJ, SACM, SS, SKD, and SUS and nitrided steel types such as SACM are exemplified.

  INDUSTRIAL APPLICABILITY The present invention can be applied to a film forming apparatus and a film forming method for performing a surface treatment for applying a compressive residual stress to a work (workpiece) such as a gear and forming a film.

DESCRIPTION OF SYMBOLS 1 ... Film formation apparatus 10 ... Processing chamber 11 ... Partition plate 12, 13 ... Storage part 14 ... Electric insulator 15 ... Work 16 ... Work holding jig 17 ... Mounting table 20 ... Surface treatment mechanism 21 ... Injection port 22, 26, DESCRIPTION OF SYMBOLS 28, 32 ... Communication path 23 ... High pressure pump 25 ... Mixing mechanism 27, 33 ... Low pressure pump 30 ... Film formation mechanism 31 ... Injection port 35 ... Filter 40 ... Cyclone 41 ... Storage part 60 ... Electrode 62 ... Power supply

Claims (8)

A film forming apparatus for applying a surface treatment to impart compressive residual stress to a work supported in a processing chamber and forming a film on the work,
A surface treatment mechanism that is movable along the workpiece, and applies compressive residual stress by injecting an electrolytic solution containing a projectile material onto the surface of the workpiece at a high pressure,
A film forming mechanism that is movable along the work, and forms a film by injecting an electrolyte on the surface of the work at a low pressure;
The workpiece is electrically connected to the anode side of the power source,
The electrode of the film forming mechanism is electrically connected to the cathode side of the power source,
The film forming apparatus, wherein the spray port of the surface treatment mechanism and the spray port of the film forming mechanism are arranged concentrically. The coating film forming apparatus according to claim 1, wherein the projection material-containing electrolytic solution and the electrolytic solution are separately stored in a storage portion at a lower portion of the processing chamber. The electrolytic solution containing the projecting material and the electrolytic solution are ejected in a coaxial direction so that the electrolytic solution surrounds the electrolytic solution containing the projecting material, and the electrolytic solution containing the projecting material is injected at 0.1 MPa to 300 MPa. The film forming apparatus according to claim 1, wherein the electrolytic solution is sprayed at 0.01 MPa to 1 MPa. The film forming apparatus according to claim 1, wherein the surface treatment mechanism and the film forming mechanism move integrally. The film forming apparatus according to claim 1, wherein the workpiece is made of iron or an iron alloy, and the film formed by the film forming mechanism is a sulfide-based solid lubricating film. A film forming method for forming a film on a workpiece,
While positively charging and injecting the projecting material-containing electrolyte at high pressure onto the rotating workpiece,
A film forming method in which a negatively charged electrolytic solution is sprayed onto the workpiece at a low pressure concentrically with the electrolytic solution containing the projection material. The electrolytic solution containing the projecting material and the electrolytic solution are ejected toward the coaxial direction so that the electrolytic solution surrounds the electrolytic solution containing the projecting material, and the electrolytic solution containing the projecting material is injected at 0.1 MPa to 300 MPa. The film forming method according to claim 6, wherein the electrolytic solution is sprayed at 0.01 MPa to 1 MPa. The film forming method according to claim 6 or 7, wherein the workpiece is made of iron or an iron alloy, and the film formed by the film forming mechanism is a sulfide-based solid lubricating film.

Images