JP2002356773A - Method for removing droplet of coating film, and method for evaluating adhesivity of coating film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a droplet removing method by which the droplet of a coating film deposited in the arc-type physical vapor deposition process can be easily and reliably removed without damaging the film, and evaluating adhesivity of the coating film simultaneously with removal of the droplet. SOLUTION: A work 1 with TiN film 12 formed thereon is moved at a speed of 1 mm/sec., and high-pressure water of 1,500 kgf/cm<2> is ejected against the TiN film 12 at the distance L of ejection of 25 mm, and the angle Q of ejection of 90 deg.. The droplet 2 adhered to the TiN film is removed by the high- pressure water. If the adhesivity of the TiN film 12 is low, the TiN film 12 is peeled simultaneously with removal of the droplet 2, and the adhesivity of the TiN film can be reliably evaluated by a simple visual inspection.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for removing droplets from a coating film and a method for evaluating adhesion.
More specifically, a droplet removal method that can easily and reliably remove droplets of a coating film formed by an arc-type physical vapor deposition process, and an adhesion evaluation that can evaluate the adhesion of the film while removing the droplets. About the method. The method for removing droplets and the method for evaluating the adhesion of the coating film of the present invention include removing droplets from the coating film of machine parts, cutting tools, molds, decorative articles, insulating film products, functional film products, etc., and the adhesion of the film. Is widely used in the evaluation of and related fields.

[0002]

2. Description of the Related Art In recent years, as a method of forming a coating film, a method of forming a coating film on a film substrate by an arc-type physical vapor deposition process has become widespread. According to such an arc type physical vapor deposition process, there is an advantage that a coating film having a dense and uniform film thickness can be efficiently produced.

[0003] However, in this arc type physical vapor deposition process, it is usually 0.1 to 2.0 µm, and depending on the processing conditions, it is 1 to 2.0 µm.
Droplets (molten particles) having a particle size of about 0.0 to 40.0 μm adhere and solidify on the surface of the coating film, and are formed. If the droplets are not removed, the function of the coating film (for example, There are problems such as a decrease in slidability and abrasion resistance) and a decrease in appearance gloss. Therefore, conventionally, as shown in FIG. 12, a paper wrap 100 (for example, a paper wrap #
In general, the droplets 2 adhered to the coating film 12 are removed using a method such as 1000). In addition, the adhesion of the coating film formed by the arc type physical vapor deposition process to the coating substrate is an important quality control item, and after removing the droplets with a paper wrap as described above, a diamond indenter is applied to the coating film. It has been common practice to perform a scratch test, such as scratching while applying a load, and evaluate the adhesion based on a change in the surface of the coating film.

However, in the above-described conventional method of removing droplets by using paper wrap, the wrapping process is performed in a state in which the removed droplets and dropped abrasive grains are involved, so that the coating film is scratched or worn (see FIG. 1). 1
3), and the functionality of the coating film may be reduced. Further, when the coating substrate has an extremely complicated shape such as a mold, it cannot be applied because the pressure cannot be applied uniformly to the coating film. Further, the paper wrap may have uneven removal due to the abrasive particles falling off and deteriorating due to long-term use. Furthermore, when the coating substrate has a simple shape, it is possible to mechanize the lapping process. However, when the coating substrate has a complicated shape, it is difficult to mechanize the lapping process, resulting in poor work efficiency.

[0005] Further, in the above-mentioned conventional method for evaluating the adhesion by the scratch test, the reliability of the evaluation result is low. This is because it is difficult to determine whether the surface change of the coating film is exfoliation or a crack, the fracture mode varies depending on the film type, and it is difficult to compare the evaluation results. This is because the evaluation is not performed and the wear deterioration of the diamond indenter cannot be avoided. In addition, there is a problem that the work subjected to the test cannot be used as a product due to scratches.

It is known that scale removal of the slab surface at the time of hot rolling is performed using high-pressure water having a pressure of about 4 kgf / cm ² (Japanese Patent Application Laid-Open No. 9-308909). Further, there is known a method in which a temporary protective film on a painted surface of a completed vehicle or the like is peeled off by high-pressure water having a pressure of ³ to 60 kgf / cm ² sprayed on the edge and the painted surface (Japanese Patent Laid-Open No. 9-2).
No. 4915). Further, the residue of the coating agent on the surface of the casting mold is reduced to about 1033 to 2066 kgf / cm.
A method is known in which the high-pressure water having a pressure of ² is removed by injection (Japanese Patent Laid-Open No. 2000-262990). But,
These prior arts do not aim at removing droplets generated on the surface of the coating film formed by the arc physical vapor deposition process. In addition, 30 to 60 kgf / cm
A method is known in which a high-pressure fluid having a pressure of ² is injected to evaluate the adhesion strength of the conductor pattern based on a change in the shape of the conductor pattern (JP-A-3-255335). However, this conventional technique does not aim at all to evaluate the adhesion of the coating film after removing the droplet.

[0007]

As described above, the present invention provides:
An object of the present invention is to provide a method for removing droplets of a coating film formed by an arc-type physical vapor deposition process, which can easily and surely remove the droplet without damaging the film. Further, another object of the present invention is to provide an adhesion evaluation method capable of easily and reliably evaluating the adhesion of a coating film in addition to the above objects.

[0008]

According to a first aspect of the present invention, there is provided a droplet removing method, wherein high-pressure fluid is jetted onto a surface of a coating film formed by an arc type physical vapor deposition process to remove the droplet. And

The method for evaluating adhesion according to claim 2 is a method for removing droplets by injecting a high-pressure fluid onto a surface of a coating film formed by an arc-type physical vapor deposition process. Evaluating the adhesion of the coating film based on the presence or absence of peeling of the coating film.

According to the droplet removing method of the present invention, there is an advantage that droplets of a coating film formed by the arc type physical vapor deposition can be easily and reliably removed without damaging the film. According to the adhesion evaluation method of the present invention, the droplets of the coating film formed by the arc-type physical vapor deposition can be easily and reliably removed without damaging the film, and the adhesion of the film can be easily and easily reduced. There are advantages such as reliable evaluation.

The "coating film" is not particularly limited as long as it is a film that can be formed by an arc-type physical vapor deposition process. The types of coating films include TiN, TiCN, CrN, ZrN, and TN.
iAlN and the like can be mentioned. The functions of the coating film include, for example, improvement in slidability, abrasion resistance, corrosion resistance, oxidation resistance, and the like. Further, as the material of the coating substrate on which the coating film is formed, cemented carbide, SKH type, SKD type, SUS type, SC, SCM,
SNCM, pre-hardened steel, Al alloy, Ti alloy, Cu
System, cermet and the like. Examples of product applications obtained by appropriately combining a coating film and a coating substrate include a machine component, a cutting tool, a mold, a decorative product, an insulating film product, a functional film product, and the like. In particular, sliding parts such as shims used for automobile engine valves can be mentioned.

The type, pressure, injection conditions, etc. of the "high-pressure fluid" are not particularly limited as long as droplets can be removed. As the type of high-pressure fluid, it is preferable to use water that is easy to handle and has no problem of environmental pollution. Further, the pressure of the high-pressure fluid is appropriately set according to the type of the coating film and the like, but usually, the droplet can be removed, and the coating film having good adhesion is formed from the coating substrate. The pressure range is set so as not to exfoliate. Specifically, it is preferably 700 kgf / cm ² or more, more preferably 1000 kgf / cm ² , from the viewpoint of improving droplet removal efficiency.
² or more, more preferably 1300 kgf / cm ² or more. The pressure of the high-pressure fluid is usually 4000 kgf / cm ² or less from the viewpoint of preventing the peeling of the coating film.

Usually, droplets are removed by a relative movement between an injection nozzle for injecting a high-pressure fluid and a coating film to be injected. Here, the injection angle Q of the high-pressure fluid (see FIG. 2) is 45 ° in terms of improving the efficiency of removing droplets.
The angle is preferably at least 60 °, more preferably at least 75 °. In addition, the number of repetitions (the number of passes) of the injection of the high-pressure fluid is preferably 2 or more, more preferably 5 or more, and still more preferably 10 or more from the viewpoint of improving droplet removal efficiency. . The number of repetitions of this injection is typically 15 in that most droplets can be removed.
Times or less. Further, the injection distance L (see FIG. 2) of the high-pressure fluid is preferably 100 mm or less, more preferably 50 mm or less, further preferably 25 mm or less from the viewpoint of improving droplet removal efficiency. The injection distance L is usually 1 mm or more in that the high-pressure fluid can be injected smoothly. The relative moving speed between the high-pressure fluid side and the coating film side is 0.1 to 1 in terms of improving the droplet removal efficiency.
It is preferably 0.0 mm / sec, more preferably 0.3 to 5.0 mm / sec, and still more preferably 0.5 to 3.0 mm / sec. In addition, the area of one injection port of the injection nozzle may be 0.005 mm ² or more in that the impact force, which is a force instantaneously acting on the coating film, is increased to improve the efficiency of removing droplets. preferably, more preferably 0.020 mm ² or more, further preferably 0.040 mm ² or more. The area of this injection port is usually 1.000 mm ² or less.
Further, the impact force of the high-pressure fluid is preferably 0.15 kgf or more, more preferably 0.50 kgf.
It is more preferably at least 1.20 kgf. This impact force is usually 2.00 kgf or less. Incidentally, the various injection conditions of the high-pressure fluid can be set in an appropriate combination.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the drawings. The work 1 used in the droplet removing method of the present embodiment has a diameter d1 as shown in FIG.
(30 mm) disk-shaped coating substrate 11 and coating film 12 (hereinafter also referred to as coating) having a thickness s (about 3 μm) formed on the upper surface side of the coating substrate 11 by an arc-type physical vapor deposition process. ). The material of the coating substrate 11 is SCM15 (carburized), and the film type of the coating 12 is TiN. The formation of the film 12 by the arc-type physical vapor deposition process allows the work 1
Has many droplets 2 adhered to the surface of the film 12. Note that the work 1 is appropriately moved at a predetermined moving speed by a transporting means (not shown).

As the apparatus 3 for carrying out the droplet removing method of the present embodiment, a high-pressure pump 31 capable of supplying a high-pressure fluid of a predetermined pressure, and a pipe connected to the high-pressure pump 31 for injecting a high-pressure fluid can be provided. And an injection nozzle 32. This injection nozzle 32, as shown in FIG.
It is positioned and fixed at a predetermined fixing position B by a fixing means (not shown) as appropriate, and in this fixed state, a predetermined injection distance L and a predetermined injection angle Q with respect to the work 1 are set.

As shown in FIG. 3, the injection nozzle 32 has a plurality of injection ports 321 having a predetermined nozzle diameter. Further, the injection nozzle 32 rotates eccentrically at a predetermined rotation speed. Therefore, each injection port 3
The high-pressure fluid injected from 21 becomes three elliptical cones,
The workpiece 1 is hit by an elliptical surface having a predetermined eccentric diameter d2, and the elliptical surfaces adjacent to each other are set so as to have a diameter d1 of the workpiece 1 as a whole.

Next, a method of removing droplets according to the present embodiment will be described. First, as the removal conditions, the type of high-pressure fluid: water, the moving speed of the work: 1 mm / sec
c, pressure of high-pressure fluid: 1500 kgf / cm ² , injection distance L: 25 mm, injection angle Q: 90 °, nozzle diameter:
0.25 mm, number of injection ports: 3, number of rotations of injection nozzles:
2000 rpm, the eccentric diameter d2 of the high-pressure fluid d2: 10 mm, and the number of passes: once.

The pressure of the high-pressure fluid: 1500 kgf / c
m ² is set on the basis of the result of Experimental Example 1 described later, and a film which can remove droplets 2 generated in the film 12 and has good adhesion to the film type TiN of the film 12 12 is a pressure value at which the film 12 does not peel off from the coating substrate 11. The impact force of the high-pressure fluid is F = 2 × A ×
P / 100, F: impact force (kgf), A: ejection port area (mm ² ), P: pressure of high-pressure fluid (kgf / cm ² ), about 1.47 kgf.

In the removing step, high-pressure water having a pressure of 1500 kgf / cm ² is jetted from the three jet ports 321 of the jet nozzle 32 by the action of the high-pressure pump 31.
The injection nozzle 32 is eccentrically rotated at a rotation speed of 2000 rpm. Next, when the work 1 is moved at a moving speed of 1 mm / sec, high-pressure water is sprayed uniformly on the entire surface of the coating 12 of the work 1, and the droplet 2 is moved from the surface of the coating 12 by the high-pressure water. Removed.

Next, in the evaluation step, the film 12
After the high-pressure water is sprayed, the adhesion of the coating 12 is evaluated based on whether or not the coating 12 has peeled off. That is, as shown in FIG. 4, in the work 1 before and after the removal process of the droplet 2, the work 1A, 1
E is evaluated as a film having good adhesion.
On the other hand, the workpieces 1B, 1C, and 1D in which the coating 12 is exfoliated before and after the treatment, and the surface color (gold) of the coating and the surface color (black) of the coating base material are mixed, have low adhesion. It is evaluated as a film. In FIG. 4, the numerical values in parentheses of each of the works 1A to 1E indicate the scratch strength obtained by a conventional scratch test. In the present embodiment, the adhesion of the film 12 is evaluated by visual inspection.
The present invention is not limited to this. For example, the adhesion may be appropriately evaluated by a photographing unit, an image processing unit, or the like. Further, in the present embodiment, the removal step is performed by fixing the injection nozzle 32 at the fixed position B, but is not limited thereto.
For example, when the workpiece has a complicated shape such as a mold, that is, when the coating shape is complicated, the injection nozzle is moved according to the coating shape, and a high-pressure fluid is injected with a uniform pressure over the entire coating. it can.

As shown in FIG. 5, in the work 1 evaluated as good in the evaluation process, as shown in FIG. 5, the state of the film 12 shows a good surface shape without damage such as scratches and abrasion. As shown in FIGS. 6 and 7, droplets 2 having a problematic particle size (0.1 to 2 μm) were uniformly removed without unevenness in removal, and no reduction in appearance gloss was observed.

Here, a friction and wear test was performed on the workpiece 1 from which the droplets 2 were removed by the removing method of the present embodiment. In this test, as shown in FIG.
Made of a ball 4 made of a steel material with respect to the upper surface of the work 1 at a peripheral speed of 2 m
The ball 4 was rolled at a surface pressure of 50 kgf / cm ² for ² seconds, and the wear amount of the ball 4 at that time was measured. As a comparative example, a friction and wear test was performed on the work 1 from which the droplet 2 was removed by the conventional lapping process under the same conditions, and the ball 4 was removed.
Was measured for the amount of wear. As a result, as shown in FIG. 9, in the present embodiment, the amount of generated ball abrasion is about ４ of that in the comparative example, and it can be said that the opponent aggressiveness, which is one of the functions of the TiN film, is small.

Further, in the above-described evaluation step, the adhesion can be easily and reliably evaluated by a visual inspection based on a difference in color of the surface of the work 1. Further, since a surface change (color change due to exfoliation) appears in a relatively large surface area of the coating film surface of the work, the evaluation can be performed more easily and reliably. In addition, a work evaluated to have low adhesion does not have a flaw or the like unlike the conventional scratch test, so that the work can be used again.

Next, in the droplet removal method of the present invention, when various removal conditions were changed, Experimental Examples 1 to 5 were conducted to examine the correlation between the changed removal conditions and the amount of droplet removal. Will be described.

In Experimental Example 1, the correlation between the pressure of the high-pressure fluid and the remaining amount of droplets was examined. As the work, a work on which a TiN film was formed in the same manner as in the above embodiment was used. The removal conditions include the type of high-pressure fluid: water, the moving speed of the workpiece: 1 mm / sec, and the injection distance L: 25 m
m, injection angle Q: 90 °, nozzle diameter: 0.18 mm,
Number of injection ports: 3, number of rotation of injection nozzle: 2000 rpm
m, the eccentric diameter d2 of the high-pressure fluid: 10 mm, and the number of passes: 1. According to the first experimental example, as shown in FIG. 10 (a), when the pressure of the high-pressure fluid is 1000 kgf / cm ² or more, the droplet removal efficiency is improved, and
It can be seen that most droplets can be removed at f / cm ² or more. Therefore, in order to remove the droplets of the TiN film, the pressure of the high-pressure fluid is 1000 kgf /
cm ² or more (more preferably, 1500 kgf
/ Cm ² or more). However, the pressure of the high pressure fluid is 4000k
If it exceeds gf / cm ² , TiN having good adhesion
4000 kgf / cm to remove the film itself
Must be ² or less.

In Experimental Example 2, the correlation between the ejection angle of the ejection nozzle and the remaining amount of the droplet was examined. As the work, the same work as that of the above-described experimental example 1 was used. Further, as the removal conditions, the same settings as in Experimental Example 1 were made except that the injection angle Q was changed to an arbitrary value and the pressure of the high-pressure fluid was set to 1500 kgf / cm ² . According to Experimental Example 2, FIG.
As shown in (b), it can be seen that most droplets can be removed when the injection angle Q is 90 °. Therefore, Ti
In order to remove the droplets of the N film, it is preferable that the spray angle Q is set to about 90 ° so that the high-pressure fluid is substantially perpendicular to the film surface.

In Experimental Example 3, the correlation between the number of passes and the remaining amount of droplets was examined. As the work, the same work as that of the above-described experimental example 1 was used. Also, as removal conditions,
Change the number of passes to an arbitrary value and increase the pressure of the high-pressure fluid to 1500.
The settings were the same as in Experimental Example 1 except that kgf / cm ² was used. According to Experimental Example 3, as shown in FIG. 10C, it can be seen that the efficiency of droplet removal is improved by increasing the number of passes.

In Experimental Example 4, the correlation between the ejection distance L of the ejection nozzle and the remaining amount of the droplet was examined. As the work, the same work as that of the above-described experimental example 1 was used. Also,
The removal conditions were the same as in Experimental Example 1, except that the injection distance L was 25 mm and 50 mm, and the pressure of the high-pressure fluid was 1500 kgf / cm ² . According to Experimental Example 4, as shown in FIG. 11A, it can be seen that the shorter the injection distance L, the higher the droplet removal efficiency.

In Experimental Example 5, the correlation between the nozzle diameter of the injection nozzle and the remaining amount of droplets was examined. As the work, the same work as that of the above-described experimental example 1 was used. As the removal conditions, the nozzle diameter and the number of passes were changed to three values, respectively, and the pressure of the high-pressure fluid was changed to 1500 kgf / cm.
Except for using ² was set to a value similar to that of Experimental Example 1. According to Experimental Example 5, as shown in FIG. 11B, it can be seen that the larger the nozzle diameter, the higher the droplet removal efficiency. This is because the larger the nozzle diameter, the larger the above-mentioned impact force becomes.

[0030]

According to the droplet removing method of the present invention, the droplets of the coating film formed by the arc type physical vapor deposition can be easily and surely removed without damaging the film. Further, according to the droplet removing method of the second aspect, in addition to the effect of the method of the first aspect, the adhesion of the film can be easily and reliably evaluated.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram for describing a droplet removing method according to an embodiment.

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is an explanatory diagram for explaining an injection nozzle.

FIG. 4 is an explanatory diagram for explaining an evaluation step.

FIG. 5 is an explanatory diagram for explaining a surface shape of a film after droplet removal.

FIG. 6 is also an explanatory view based on an optical microscope photograph.

FIG. 7 is an explanatory diagram also using a three-dimensional image.

FIG. 8 is an explanatory diagram for explaining a friction and wear test of a film after droplet removal.

FIG. 9 is an explanatory diagram for comparing and explaining the opposing aggressiveness of the film after droplet removal by the method of the present embodiment and the conventional lapping method.

FIGS. 10A and 10B are explanatory diagrams for explaining an experimental example for examining the correlation between various removal conditions and droplet removal efficiency, wherein FIG. 10A shows the results of Experimental Example 1, and FIG. The results according to Example 2 are shown, and (c) shows the results according to Experimental Example 3.

FIGS. 11A and 11B are explanatory diagrams for explaining an experimental example, wherein FIG. 11A shows the result of Experimental Example 4 and FIG. 11B shows the result of Experimental Example 5.

FIG. 12 is an explanatory diagram for explaining a droplet removing method by a conventional wrapping method.

FIG. 13 is an explanatory diagram for explaining a surface shape of a film after removing a droplet by a conventional lapping method.

[Explanation of symbols]

2; Droplet, 11; Coating substrate, 12; Coating film.

Claims (2)

[Claims] 1. A method for removing droplets of a coating film, comprising spraying a high-pressure fluid onto a surface of the coating film formed by an arc-type physical vapor deposition process to remove droplets. 2. A removing step of injecting a high-pressure fluid onto a surface of a coating film formed by an arc-type physical vapor deposition process to remove droplets, and determining whether the coating film has peeled off during the removing step. Evaluating the adhesion of the coating film based on the evaluation method.