JPH0215183A - Surface reforming method and surface reforming device - Google Patents

Abstract

PURPOSE:To allow adequate reforming and reinforcing of only the part of a large-sized structure by constituting a large-sized sample so as to constitute a part of a vacuum vessel and irradiating the sample surface on the vessel side with charge particles. CONSTITUTION:The part to be worked of the large-sized structure 12 is supported by a sealing device 13 having a flexible structure in such a manner as to be exposed to an atmosphere 3 in the vessel so that the entire part in the vacuum vessel 1 is kept hermetic. A charge particle irradiation device 4 or an electron beam irradiation device is mounted in the vacuum vessel 1. Gas is introduced from a gas introducing port 19 into the vessel and a DC voltage is impressed between a filament 5 and the vessel 1 to form gaseous plasma. The metal 10 in a crucible 9 is evaporated. A voltage is impressed between drawing-out electrodes 7-1 and 7-2 and the positive charge ions are drawn out of the plasma into the atmosphere 3. The surface of the structure 12 is then irradiated with these ions. TiN, etc., are deposited on the partial surface of the structure 12 with the good adhesive property in such a manner.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to a surface modification device that changes the properties of a sample surface by irradiating charged particles with the surface of a large structure. The present invention relates to a surface modification device and a surface modification method suitable for use in surface modification.

[Prior Art] As a prior art related to a surface modification device that changes the properties of the surface of a sample by irradiating charged particles, for example, Journal of Vacuum Science and Technology, A4-(3).

(1,986), pp. 784-787 (Jou
rnal of Vacuum Sc〕-ence
& Technology A4 (3).

(1986), pp. 784-787) and the like are known. In this conventional technique, a film of a compound of evaporated metal and charged particles is formed on the surface of a sample placed in a container using charged particles from an ion source and metal gas evaporated from an electron beam evaporator.

[Problems to be Solved by the Invention] The above-mentioned prior art proposes that when the sample is small and can be stored in a vacuum container, the surface of the sample is modified by irradiating the sample with charged particles B11. However, if the sample is too large to be stored in a vacuum container, the surface modification of the sample cannot be carried out at t5.

Generally, in order to irradiate charged particles, the flight region of the charged particles, that is, the inside of the vacuum container in the prior art described above, needs to be in a vacuum state with a pressure of 10-3 to 10-5 GoOrr. It was thought that a method of surface modification using charged particle irradiation could not be adopted in a state where vacuum IJI was not possible. Therefore, the sample
The general idea was that it could be stored in a vacuum container.

For example, water turbines for hydroelectric generators are exposed to high-speed water flows containing sediment, so there is a problem in which only the upstream tips of the turbine blades wear out. , thermal spraying, 9-part quenching, melting, and other methods to partially harden the surface to improve wear resistance.

It would be very effective to perform surface modification by charged particle irradiation for the above-mentioned applications, and in the above-mentioned example, it would be very effective to perform surface modification to improve wear resistance. However, conventionally, there has been no known method for irradiating a portion of a large structure with charged particles.

The purpose of the present invention is to make it possible to irradiate a portion of an object such as a large structure with charged particles or an electron beam to modify the surface of the object, which is difficult to store entirely in a vacuum container. The object of the present invention is to provide a surface modification device and a surface modification method that make it possible.

[Means for Solving the Problem] According to the present invention, the object is to separate the surface of the sample itself to be modified and the surface modification so that the large sample itself becomes a part of the vacuum vessel. This is achieved by maintaining a vacuum seal between the device and the vacuum container, and making it possible to irradiate the sample surface on the vacuum container side with charged particles.

[Function] The airtight container portion, which is composed of the sample to be surface modified and the vacuum container of the surface modification device, is evacuated by a vacuum evacuation device. The charged particle irradiation device installed on the vacuum container side of the surface modification device performs irradiation inside the evacuated container.
By irradiating the surface of an object with charged particles, it is possible to change the properties of the object's surface.

This makes it possible to perform partial surface modification even on large structures.

[Example] Hereinafter, an example of the surface modification apparatus and surface modification method according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a sectional view showing the configuration of a first embodiment of the present invention. In FIG. 1, 1 is a vacuum container, 2 is a vacuum evacuation device, 3 is an atmosphere inside the container, 4 is a charged particle irradiation device, 5 is a filament, 6 is a container of the charged particle irradiation device, 7 is a drawer,
Electrodes, 7-1 is an electrode on the plasma chamber side, 7-2 is an electrode on the vacuum vessel side, 8 is a permanent magnet group, 9 is a crucible, 10 is a metal, 11
- is a metal particle, 1-2 is a large structure, 13 is a vacuum sealing device, 1.4, 1.6 is a sealing part, 15 is a flexible structure, 17 is an end face of a vacuum container, 19 is a gas introduction L1 .

A first embodiment of the present invention shown in FIG.
and a vacuum sealing device for vacuum sealing between the end surface 17 of the vacuum container 1 and the large structure 12 which is the liquid container.
It is composed of

The vacuum, empty container 1 is connected to a vacuum evacuation device 2, and the atmosphere 3 inside the container is evacuated to about 10-''I'orr.

The charged particle irradiation device 4 includes a filament 5 and a container 6 that serves as an anode for the filament 5, and generates plasma in the container 6 of the charged particle irradiation device 4. An extraction electrode 7 is provided between the container 6 and the top of the vacuum container.

This extraction electrode 7 is composed of two mesh-like electrodes, an electrode 7-1 on the plasma chamber side and an electrode 7-2 on the vacuum vessel side, and the electrode 7-2 has a negative potential with respect to the electrode 7-1. A voltage is applied such that positively charged ions are extracted from the plasma in the container 6 to the vacuum container 1 side. On the outer periphery of the container 6 of the charged particle irradiation device 4, a permanent magnet group 8 is arranged so that the magnetic poles are oriented in the radiation direction and the adjacent polarities alternate. Inside the vacuum container 1, a crucible 9 containing a metal such as titanium is placed, and the metal]-〇 is heated by the electronic beam 11 and evaporated into metal particles 1.1, Diffusion into container T.

The large-scale structure 12 that is the workpiece may be, for example, a turbine blade as shown in the figure, and the large-scale structure 12 may be a turbine blade or the like as shown in the figure.
A vacuum container 1 supported by a vacuum sealing device 13 having a flexible structure and having a - section of a large structure 12 on its inner surface.
The entire interior is kept airtight. The vacuum seal device 13 includes a seal portion 14 shaped along the surface of a large structure 12 serving as a sample (workpiece), and a seal portion 14 for connecting the large structure 12 and the vacuum container with a certain degree of freedom. A seal portion 16 for airtightly coupling the flexible structure 15, for example, a bellows structure member, to the end surface 17 of the vacuum container 1.
It is composed of

A method for changing a portion of the large structure 12, the portion 18 indicated by the thick solid line in the figure, to a property with high wear resistance using the surface modification device of the present invention configured as described above will be described below. do.

First, the large structure 12 and the vacuum container 1 are airtightly connected, and the atmosphere inside the container is reduced to 10-6'rorr by the vacuum gas loss device 2.
Thoroughly exhaust the air to pj degrees. After that, gas introduction [119
Nitrogen gas is introduced from
-''Torr state, by applying a current to the filament 5 and at the same time applying a voltage of 1ffE between the filament 5 and the container 6, the current is emitted from the filament l-5.
Thermionic electrons of P are accelerated to generate nitrogen gas plasma in the container 6. On the other hand, the metal 10 in the crucible 9, such as titanium, is evaporated to generate titanium vapor in the atmosphere 3 inside the container. In this state, the two electrodes 7-1.
When a voltage of about 10KV to 20KV is applied between 7/-2, positively charged ions are extracted from the plasma generated in the container 6 of the charged particle irradiation device W4 into the atmosphere 3 inside the vacuum container 1. , irradiates the surface of large structure ↑2. At this time, the positively charged ions, that is, the nitrogen ions combine with the metal particles 11, that is, the titanium particles, in the atmosphere 3 inside the container to form titanium nitride, and this titanium nitride is deposited on the surface of the large structure 12 with good adhesion. do.

According to the first embodiment of the present invention described above, it is not necessary to put the entire large structure to be processed into a vacuum container, so the surface modification device can be small-sized, and the large structure can be processed easily. It becomes possible to perform surface modification on only the required portions of the structure in a fixed state.

In addition, in the method using the surface inj reforming apparatus according to the first embodiment of the present invention, metal vapor deposition and ion irradiation are performed simultaneously, so the temperature of the large structure to be processed can be reduced.
It is possible to form a film with sufficient adhesion on the surface of a large structure without fading, so even structures that have already undergone processes such as heat treatment can be processed without changing the state of the structure. This process does not generate thermal stress or the like. That is, according to the first embodiment of the present invention described above, even if the large structure has undergone machining, heat treatment, etc. and is assembled, the surface of the structure can be modified. becomes possible.

FIG. 2 is a sectional view showing the configuration of a second embodiment of the present invention. In FIG. 2, 21 is a large planar structure, 22
is a second charged particle irradiation device, 23 is a surface modification part,
Other symbols are the same as in FIG. 1.

A second embodiment of the present invention shown in FIG. 2 is an example in which the present invention is applied when a large structure to be processed is a flat surface, and a charged particle irradiation device 4 similar to that shown in FIG. and the first
A second charged particle irradiation device 22 is provided separately from the charged particle irradiation device 4 , and is capable of irradiating charged particles of a different type from that of the first charged particle irradiation device 4 . Further, in this embodiment, since the large structure 21 has a planar structure, the first
There is no need for a vacuum sealing device with a flexible structure as in the embodiment, and the surface modification device according to the present invention can be used simply by being placed on the flat surface of the large structure 12 where the surface modification is to be performed. , vacuum sealing between them can be performed using a well-known O ring or the like.

The vacuum container 1 uses a part of a large planar structure 21 to form a container internal atmosphere 3, which is evacuated by a vacuum evacuation device 2. The first charged particle irradiation device 4 has the same structure as that shown in FIG. 1, and its details are omitted and not shown in FIG. This first charged particle irradiation device 4 irradiates with ions of a substance that is a gas at room temperature, such as nitrogen ions. On the other hand, the second charged particle irradiation device 22 is used to irradiate ions of a substance that is solid at room temperature, such as metal ions. As a metal ion irradiation device,
For example, Thjn
5solid Fi]ms) Volume 9 (1982), No. 1
The cluster ion beam generator described on pages 9 to 9 can be used.

Surface modification of a large structure 21 using the second embodiment of the present invention shown in FIG. 2 is carried out as follows.

The "vacuum container" is sealed in a vacuum state and attached to the large structure 21, and the atmosphere 3 inside the container is heated to 10-'To
Exhaust to rr. Thereafter, for example, nitrogen gas is introduced from the gas inlet 19 to generate plasma in the container 6 , and the extraction electrode 7 extracts nitrogen ions into the atmosphere inside the container. This nitrogen ion is irradiated as an ion beam onto the part facing the area.

At the same time as described above, for example, titanium, boron, etc. are ionized from the second charged particle irradiation device 22 and drawn out into the atmosphere inside the container at a relatively low voltage (several 100 V to several KV), and the large structure 21 is irradiated with an ion beam. As a result, a film of titanium nitride, boron nitride, or the like is formed on the surface modified portion 23 of a predetermined portion of the large structure 2].

In the above description, by controlling the accelerating voltage when extracting charged particles from the charged particle irradiation device 4 or the amount of ions irradiated from the charged particle irradiation device 22, the particles are formed on the surface modified portion 23 of the large structure 12. It is possible to control the adhesive strength, crystal structure, orientation, etc. of the film. As a result, a film having excellent hardness, corrosion resistance, and wear resistance can be formed on a portion of a large structure.

The second embodiment of the present invention described above is a case where the large structure to be processed is on a flat surface, and there is no need for a vacuum sealing device with a flexible structure like the first embodiment shown in FIG. Also, the vacuum container 1 can be used as a large structure 21.
It is possible to run on both sides of the large structure 21- while maintaining a vacuum-sealed state, and it is possible to continuously extend the surface-modified portion 23 of the large structure 21-.

Therefore, according to the present invention, it is possible to perform surface modification on a wide surface of a planar dog-shaped structure having a large area.

FIG. 3 is a sectional view showing the configuration of a third embodiment of the present invention. In FIG. 3, 31 is a large structure, 33 is a third charged particle irradiation device, 34 is a surface modification section, and other symbols are the same as in FIG. 1.

The third embodiment of the present invention shown in FIG. 3 is an example in which three charged particle irradiation devices are provided, and the second embodiment of the present invention shown in FIG.
For example, in the process of surface modification of the workpiece, the first
The charged particle irradiation device 4 can irradiate not only charged particles with an acceleration energy different from that of the charged particle irradiation device 4, such as positive ion beams 11, but also electron beams and the like. The third embodiment of the present invention includes a vacuum container 1, a vacuum evacuation device 2, a large structure 31, a flexible vacuum seal device 43, a first charged particle irradiation device 4, and a second charged particle irradiation device 22. , a third charged particle irradiation device 33, and forms a surface modification portion 34 in a part of the large structure 31.

In this third embodiment, the first charged particle irradiation device 4
irradiates an ion beam of nitrogen or oxygen with relatively high energy (about IOKV to 50KV), and during this irradiation, the second charged particle irradiation device 22 irradiates an ion beam of titanium, boron, etc. with relatively low energy. (approximately several hundred volts to several kilovolts) to form a surface modified portion 34 in a predetermined portion of the large structure 31. This method is the same as that described with reference to FIG. The third charged particle irradiation device 33 in this embodiment irradiates the surface modification portion 34 of the large structure 31 with an electron beam or an ion beam of an inert gas such as argon.

The charged particle beam irradiated by the third charged particle irradiation device 33 can be used to change the properties of the surface modification portion 34 formed on the surface of the large structure 34. For example, this beam can perform a thermal effect, and the stress generated in the surface modification portion of the large structure 34 can be alleviated by the high-energy particles from the second charged particle irradiation device 4. Further, this beam can neutralize residual positive charges on the surface of the large structure 31 due to positive ion irradiation from the first and second charged particle irradiation devices, thereby eliminating residual positive charges. Generally, residual positive charges on the surface of large structures are a cause of corrosion, so if the electron beam is irradiated from the third charged particle irradiation device 33, the surface will be neutralized and corrosion resistance will be improved. can be improved.

According to the third embodiment of the present invention described above, a part of a large structure is coated with a dense film made of titanium nitride, boron nitride, etc., which has excellent wear resistance, and also has excellent corrosion resistance. It is possible to form a surface modified portion 34 that is free from stress-induced distortion.

In the third embodiment of the present invention, the third charged particle irradiation device 33 is used to irradiate the surface-modified portion of the target large structure with an electron beam to reduce the activity of the surface. , the corrosion resistance is improved, but the
Also in the first and second embodiments of the present invention shown in the figures, after forming the surface modified portion on the large structure, the first charged particle irradiation device 4
By setting the voltages applied to the two electrodes 7-1 and 7-2 of the extraction electrode 7 of the charged particle irradiation device to have opposite polarities, electrons can be extracted from the plasma generated in the container 6 of the charged particle irradiation device. It is possible to perform various actions.

FIG. 4 is a sectional view showing the configuration of a fourth embodiment of the present invention. In FIG. 4, 42 is an electron source, 43 is an electron accelerating electrode, 44 is an electron focusing electrode, and 45 is a deflection electrode, and the other symbols are the same as in FIG. 3.

This fourth embodiment of the present invention includes an electron source 42 in a vacuum vessel and an electrode 4 for controlling electrons from the electron source 42.
3 to 45 are provided to modify the surface of the large structure 31 with an electron beam.

In this embodiment, the vacuum evacuation device 2
When the electron source 42 is evacuated to a sufficiently low pressure, the electrons generated by the electron source 42 are accelerated and focused by the electrode 4.3.44 to form a beam, and by controlling the voltage applied to the deflection electrode 45, a large A predetermined range of the surface of the structure 34 is scanned.

By irradiating the focused electron beam, the surface modified portion 34 of the large structure is heated and melted, and the characteristics near the surface of the large structure are altered.

The fourth embodiment of the present invention described above has an effect that the vacuum container 1 can be made smaller because the vacuum container 1 is provided with an electron source and an electrode for controlling the electrons from the electron source. This is particularly effective when the area of the required surface modification portion is small. Furthermore, if the vacuum evacuation device 2 is configured as a plug-in type, and the flexible structure vacuum device]-3 is configured with a rubber-like elastic body and has a shape that can ensure a vacuum seal by pressing it against a large structure, It becomes possible to provide a small and handy surface modification device. Further, the third aspect of the present invention described above. In the fourth embodiment, when the surface of the large structure 31 has few irregularities, it is possible to move the vacuum container 1 on the surface 1- of the large structure while maintaining the inside of the vacuum container 1 in a vacuum state. It is.

[Effects of the Invention] As explained above, according to the present invention, the surface properties of a part of a large structure can be improved by the method of irradiating the large structure with charged particles. It becomes possible to perform modification 2 to strengthen only the parts of the structure that require wear resistance and corrosion resistance. .

[Brief explanation of the drawing]

FIGS. 1, 2, 3 and 4 respectively represent the first embodiment of the present invention. Second. FIG. 7 is a cross-sectional view showing the configurations of third and fourth embodiments. 1 Vacuum container, 2 Vacuum exhaust device, 3・Atmosphere inside the container, 4,22.33・Charged particle irradiation device, 5・
Filament, 6. Container for charged particle irradiation device, 7.
・Extraction electrode, 7-1- Plasma chamber side electrode, 7-2
Vacuum vessel side electrode, 8. Permanent magnet group, 9. Crucible, 1
0. ・Metal, 11 Metal particles, 12, 21, 31
Large structures, ]3 ・・Vacuum sealing equipment, 14.16
- Seal part, 15 - Flexible structure, 17 - End face of vacuum container, 18, 23.34 Surface modification part, 19
Gas introduction 1'', 42 electron source, 43 electron accelerating electrode, 44 electron focusing electrode, 45 deflection electrode.

Claims (1)

[Claims] 1. A vacuum container that can be sealed to a pressure lower than atmospheric pressure by a vacuum evacuation device, and at least one charged particle irradiation device or electron beam irradiation device attached to the vacuum container, A surface modification device for irradiating a surface of a sample in the vacuum container with charged particles or an electron beam, wherein the surface modification device is configured such that the sample becomes a part of the vacuum container. 2. A vacuum seal having a flexible structure between the sample and the vacuum container, consisting of a seal portion along the sample surface, a seal portion for the vacuum container, and a flexible member joining both the seal portions. The surface modification device according to claim 1, characterized in that the surface modification device is coupled with the device. 3. The surface modification apparatus according to claim 2, wherein the sample and the vacuum container are connected without using the flexible vacuum sealing device. 4. The vacuum container according to claim 1, 2, or 3 is characterized in that the vacuum container is movable over the surface of the sample while its interior is maintained in a vacuum state. Surface modification equipment. 5. At least one evaporator is provided in the vacuum container, and irradiation of charged particles from the charged particle irradiation device and evaporation of a substance from the evaporation device are performed simultaneously. The surface modification device according to one of the first to fourth items. 6. When a plurality of charged particle irradiation devices are provided, each of the charged particle irradiation devices irradiates different types of charged particles. The surface modification device described. 7. Claim 1, wherein the charged particle irradiation device is equipped with an electrode for extracting charged particles, and is capable of irradiating an electron beam by changing the polarity of the voltage applied to the electrode. The surface modification device according to item 1 of items 6 to 6. 8. After machining, heat treatment, etc. have been completed, modifying the surface of the large structure by subjecting the assembled large structure to charged particle irradiation, electron beam irradiation, or both. A surface modification method characterized by: