JP2020067421A - Material adhesion evaluation method - Google Patents

Abstract

To provide a material adhesion evaluation method capable of appropriately evaluating adhesion of an interface.SOLUTION: A material adhesion evaluation method comprises: an injection step of injecting a liquid material containing polygonal particles on the surface of a material to be evaluated having at least an interface between a first member and a second member; and a measurement step of measuring a peeling start thickness, which is the remaining thickness of the first member when peeling at the interface is started, as adhesion representing the degree of adhesion at the interface.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a material adhesion evaluation method for evaluating the adhesion of a material having an interface.

  Conventionally, for example, Patent Document 1 and Patent Document 2 have been proposed as an interface evaluation method. The interface evaluation method disclosed in Patent Document 1 is a method for evaluating the interface between the base material and the coating in a subject having a coating formed on the surface of a base material such as a metal material or a synthetic resin material, The test object is reduced by injecting spherical abrasive particles together with compressed air into the test object, based on the causal relationship between the decrease amount of the test object and the amount or time of the abrasive particles required for the decrease. Formula 1; (Strength of interface (wear ratio)) = (wear rate near the interface) / (whichever has a higher wear rate of the base material and the coating), from the strength of the interface between the base material and the coating. And the interface is evaluated. The method disclosed in Patent Document 2 jets an injection material in which abrasive particles are mixed into a liquid together with compressed air to a test object to reduce the test object, and graphs the relationship between wear time and wear depth. . And, in the paragraph [0049] of Patent Document 2, "There was a vertical straight line portion at the connecting portion between the gentle gradient and the steep gradient (FIGS. 4, 4, and 5). It is considered that the film is suddenly removed when the film becomes thin due to abrasion due to the abrasion. Therefore, if the length of the vertical straight line part is short, the layer thickness of the part that can be removed at once is thin. It is considered that the adhesion between the coating and the base material is high, and if there is no vertical straight line portion (Fig. 6), the adhesion between the coating and the base material is extremely strong or a clear interface. Is considered to be nonexistent. ”

JP, 2015-14503, A JP 2001-183279 A (Patent No. 3356415)

  By the way, since the interface evaluation method disclosed in Patent Document 1 is evaluated by the equation 1, when the wear rate of the coating is smaller than the wear rate of the base material (that is, the wear rate of the base material was adopted. In this case), the evaluation of the substrate is not appropriate, but the evaluation of the film is inappropriate. Further, since the wear rate near the interface may not be clearly evaluated in some cases, it is not sufficient to evaluate the strength of the interface by the interface evaluation method disclosed in Patent Document 1. On the other hand, in Patent Document 2, since the # 8000 abrasive grains (average grain size 1.2 μm) are used according to FIGS. 4 to 6, the peeled film thickness is small and the difference is difficult to understand. When the wear time and wear depth are the same as those of the base material, the vertical straight line portion becomes extremely difficult to understand.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a material adhesion evaluation method capable of more appropriately evaluating the adhesion of an interface.

  As a result of various studies, the inventor of the present invention wears (erosion) the material as usual when the size of the particles (abrasive grains) is changed, but when a certain wear depth is reached, the surface of the interface suddenly disappears. The phenomenon that the material peels off was found. For example, when a material composed of a combination of the material A and the material B is worn away from the surface of the material A toward the interface between the material A and the material B, the material A has a remaining thickness. Nevertheless, the material A suddenly peels off from the material B. As a result of examining the relationship between the remaining thickness of the material A (peeling start thickness) and the material B at the time of this peeling, it was found that the peeling start thickness of the material A changes depending on the type of the material B, and at the interface It was found that the degree of adhesion, which represents the degree of adhesion, can be evaluated by the peeling start thickness. Based on this finding, it has been found that the above object can be achieved by the present invention described below. That is, the material adhesion evaluation method according to one aspect of the present invention is a jetting step of jetting a liquid containing polygonal particles onto the surface of the material to be evaluated that has at least the interface between the first portion and the second portion. And a measurement step of measuring the peeling start thickness, which is the remaining thickness of the first portion when the peeling at the interface starts, as the degree of adhesion representing the degree of adhesion at the interface. Preferably, in the above-described material adhesion evaluation method, in the case where the peeling start thickness is composed of a base material as the second portion and a film formed as the first portion on the surface of the base material, It is a value obtained by subtracting the depth of weight loss due to the particles when the coating is peeled from the base material from the initial thickness of the coating. Preferably, in the above description, the depth of weight loss due to the particles when the coating is peeled from the base material is the injection step that is performed for a predetermined time, and after performing the injection step for the predetermined time. In the case where the wear depth measuring step of measuring the depth of weight loss due to the particles (wear depth) is repeatedly performed, immediately before the wear depth measuring step determined to have reached the base material in the injection step. It is the depth of the weight loss by the particles (wear depth) measured in the wear depth measuring step carried out (previously). Preferably, in the above description, the depth of the weight loss due to the particles when the coating is peeled from the base material is a value estimated based on a graph showing the relationship between the elapsed time from the start of wear and the wear depth. .. The polygonal shape (undefined shape) means a solid body having at least a corner, and the polygonal shape excludes a solid body having no corner, such as a sphere or an ellipsoid.

  Such a material adhesion evaluation method uses a liquid material containing polygonal particles to reduce the amount of a material having at least the interface between the first portion and the second portion, and removes the material when the peeling at the interface is started. Since the peeling start thickness, which is the remaining thickness of the first portion, is used as an index of the adhesiveness, the adhesiveness at the interface can be evaluated more appropriately.

  In another aspect, in the above-described material adhesion evaluation method, the particles are hard particles having an average particle size of 40 μm or more.

  According to this, a material adhesion evaluation method using hard particles having an average particle size of 40 μm or more as the particles can be provided.

  In another aspect, in these material adhesion evaluation methods described above, the particles are hard particles having a HV of 1500 or more.

  According to this, it is possible to provide a material adhesion evaluation method using, as the particles, hard particles having an HV of 1500 (Vickers hardness of 1500) or more.

  The material adhesion evaluation method according to the present invention can more appropriately evaluate the adhesion at the interface.

It is a figure for demonstrating the material adhesiveness evaluation method in embodiment. 5 is a diagram showing measurement results of Example 1 and Comparative Example 1. FIG. FIG. 3 is a diagram showing a partially enlarged measurement result in the vicinity of an interface in Comparative Example 1 shown in FIG. 2 and a measured cross-sectional shape. It is a figure which shows the measurement result of the interface vicinity in Example 1 shown in FIG. 2 which was partially expanded, and the measured cross-sectional shape. It is a figure for demonstrating the relationship between a calotest trace and a film thickness in a calotest. It is a figure for demonstrating the relationship between Example 2 thru | or Example 8 and a scratch test result.

  Hereinafter, one or more embodiments of the present invention will be described with reference to the drawings. However, the scope of the invention is not limited to the disclosed embodiments. It should be noted that in each of the drawings, the components denoted by the same reference numerals indicate the same components, and the description thereof will be appropriately omitted. In the present specification, reference numerals without suffixes are used for generic names, and reference numerals with suffixes are used when referring to individual components.

  The material adhesion evaluation method according to the embodiment includes an injection step of injecting a liquid material containing polygonal particles onto the surface of a material to be evaluated having at least an interface between the first portion and the second portion, and A measurement step of measuring a peeling start thickness, which is a remaining thickness of the first portion when peeling starts, as an adhesion degree indicating a degree of adhesion at the interface. According to this, the adhesiveness of the interface can be evaluated more appropriately. Hereinafter, it will be described more specifically by using Examples and Comparative Examples.

(Example 1 and Comparative Example 1)
FIG. 1 is a diagram for explaining the material adhesion evaluation method according to the embodiment. 1A shows an initial state, FIG. 1B shows an injection process, FIG. 1C shows a measurement process, and FIG. 1D shows a peeling start thickness. FIG. 2 is a diagram showing the measurement results of Example 1 and Comparative Example 1. The horizontal axis in FIG. 2 is the test time (the elapsed time from the start of the test (start of wear, start of weight reduction)) expressed in minutes (min), and the vertical axis thereof is the depth of erosion expressed in units of micrometers (μm). (Depth of wear (wear depth)). FIG. 3 is a diagram showing a partially enlarged measurement result near the interface in Comparative Example 1 shown in FIG. 2 and the measured cross-sectional shape. FIG. 3A is a partially enlarged view of the measurement result in the vicinity of the interface in Comparative Example 1 shown in FIG. 2, and FIG. 3B shows the measured cross-sectional shape shown every 50 minutes from the start of the test. FIG. 4 is a partially enlarged view showing the measurement result near the interface in Example 1 shown in FIG. 2 and the measured cross-sectional shape. FIG. 4A is a partially enlarged view of the measurement result near the interface in Example 1 shown in FIG. 2, and FIG. 4B shows the measured cross-sectional shape shown every 30 minutes from the start of the test. FIG. 5 is a diagram for explaining the relationship between the calotest trace and the film thickness in the calotest.

  In Example 1 and Comparative Example 1, the liquid material containing polygonal particles was changed, and the injection step and the measurement step were performed.

  The test body SP may be any material as long as it has at least an interface SF between the first portion PT1 and the second portion PT2, as shown in FIG. 1A, and is preferably subjected to surface treatment or surface modification. The material that has been used, for example, a member in which a film is formed as the first portion PT1 by a surface treatment such as plating or vapor deposition on the surface of the base material as the second portion PT2 such as metal or synthetic resin, or the first portion. It is a member or the like in which a bulk-shaped first member as the portion PT1 and a bulk-shaped second member as the second portion PT2 are joined or bonded. In these Examples 1 and Comparative Example 1 as an example, a film of AlCrN is formed on the surface of a substrate of cemented carbide (P type) by a PVD (physical vapor deposition) method (physical vapor deposition method). Thus, the test body was prepared.

In the injection step, for example, as shown in FIG. 1B, a slurry in which a predetermined amount of polygonal particles PK are dispersed in a liquid LD is used as the liquid material JS, and the slurry is subjected to the test with an injector. It was sprayed on the body SP. The polygonal shape (indefinite shape) means a solid body having at least a corner, and the polygonal shape excludes a solid body having no corner, such as a sphere or an ellipsoid. The particles PK have only to be hard enough to erode the test body in the injection step, and are, for example, ceramics such as alumina (Al ₂ O ₃ ) or zirconia (ZrO ₂ ). Generally, the Vickers hardness of alumina is about HV 1500 to HV 1600, and the particle PK is preferably HV 1500 (Vickers hardness 1500) or more. The Vickers hardness of zirconia is generally about HV1200-HV1300. The injector may be any device as long as it is capable of eroding the test body SP from the surface with a mixture of the liquid LD and the particles PK.

  More specifically, a circulation type MSE (Micro Slurry-jet Erosion) tester manufactured by Macau Co., Ltd. was used, and the slurry was sprayed at a projection distance of 10 mm and a projection angle of 90 degrees. The liquid material JS of Example 1 is a slurry in which amorphous alumina of WA # 320 (average particle diameter 41 μm) is dispersed in water at 0.3 mass%. The liquid material of Comparative Example 1 is a slurry in which amorphous alumina of WA # 8000 (average particle diameter 1.2 μm) is dispersed in water at 3 mass%. The average particle size is represented by the median size (particle size at a cumulative height of 50%) using the particle size distribution of particles (volume-based particle size distribution measured by the electrical resistance method) measured by Fujimi Incorporated. It is the particle size. If the slurry concentration is too high, the erosion may proceed quickly and the peeling start thickness may not be evaluated (measured). Therefore, the slurry concentration is preferably 3 mass% or less.

In the measurement step, for example, as shown in FIGS. 1C and 1D, the peeling start thickness T2, which is the remaining thickness T2 of the first portion PT1 when the peeling at the interface SF starts, is set to the interface SF. In order to measure the degree of adhesion in the above, first, the depth of erosion by the particles PK (erosion depth, wear depth) T (i) is first measured every predetermined prescribed time. Was done. That is, the injection step is performed for a predetermined prescribed time, and then, the wear depth measurement step of measuring the wear depth T (i) is performed, and the injection step and the wear depth measurement step are performed as described above. It was repeatedly performed until the base material was scraped off by first scraping (reducing the amount) the film by injecting the slurry (i is the number of measurement steps, i = 0 is the thickness of the first portion PT1 in the initial state). (Initial thickness) T0). The predetermined prescribed time may be arbitrary, and in the case of more detailed evaluation, a shorter one such as 1 minute or 2 minutes is preferable. Further, since the wear rate (erosion rate) differs depending on the type of the coating, it is preferable to adjust the wear rate of the coating. Further, although the predetermined prescribed time is preferably constant during the test, it may be changed, and may be changed to be short particularly in the vicinity where the peeling start thickness is assumed. In the wear depth measuring step, in these Example 1 and Comparative Example 1, in order to measure the wear depth, the cross-sectional shape of the erosion mark is measured, and the depth at the center thereof is measured as the wear depth. This is a shape measuring step. Next, secondly, the initial thickness of the film was measured (film initial thickness measuring step). Then, thirdly, the peeling start thickness was obtained by the following equation A (peeling start thickness calculation step, adhesion degree calculation step).
Formula A; (Peeling start thickness T2) = (Initial thickness T0 of coating)-(Depth of weight loss due to particles when the coating is peeled from the base material (When the coating is peeled from the base material) Wear depth at) T1)

  More specifically, in the cross-sectional shape measurement step, the cross-sectional shape of the erosion mark is measured by a surface roughness meter, for example, SURFCOM 1400D manufactured by Tokyo Seimitsu Co., Ltd., which is a stylus type two-dimensional roughness meter. It was The inclination correction is both-ends correction, the measurement length is 6 mm, the measurement speed is 0.3 mm / s, and the probe tip radius is 2 μm. The wear depth was measured by visually observing the unevenness of the cross-sectional shape curve in the central portion of the erosion mark from the curve. Then, when the erosion reaches the substrate, the shape of the central portion in the measured cross-sectional shape changes from the tendency of the shape before that, so the injection step and the wear depth measuring step (here, the cross-sectional shape measuring step). ) And are repeatedly carried out, when the wear depth read from the cross-sectional shape measured immediately before (previously) the cross-sectional shape in which the shape of the central portion has changed is measured (when the coating is peeled off from the base material). The depth of the weight loss due to the particles (the depth of wear when the coating is peeled from the base material) T1 was determined. That is, the wear depth measured in the wear depth measurement step carried out immediately before (previously) the wear depth measurement step determined to have reached the base material in the injection step, the film from the base material It is the wear depth T1 when peeled.

  In the film initial thickness measuring step, the initial film thickness T0 was measured by a film thickness measuring method such as a Calotest or a fluorescent X-ray film thickness meter.

More specifically, the Calotest was used. In this carotest, a compact type carotest (CATc) manufactured by Anton Paar Japan Co., Ltd. is used, and as shown in FIG. 5, it corresponds to a film in a recess (carotest mark) formed by the carotest. The length X (μm) of the part and the length Y (μm) of the part corresponding to the film and the base material in the carotest trace were measured, and the radius of the steel ball used for the carotest is R (μm) The film thickness t of the film is calculated by the following equation B.
Formula B; t = XY / (2R)

  In Example 1 and Comparative Example 1, the calotest was carried out at two non-eroded sound places sandwiching the erosion mark, and the average value thereof was taken as the thickness of the coating film on the test body. Here, with respect to one calotest trace, the thickness of the film was obtained by the formula B at two positions rotated by 90 degrees, and the average value thereof was taken as the thickness of the film for the one calotest trace. Therefore, the average value of the film thickness obtained by the equation B from the four XY measurement values was taken as the initial film thickness T0 of the test body.

  The measurement results of Example 1 and Comparative Example 1 thus carried out are shown in FIGS. 2 to 4 and Table 1. In Comparative Example 1, the particles (WA # 8000) having the same size described in Patent Document 2 are used.

  As can be seen from FIGS. 2 to 4, the wear depth per unit time (wear rate, slope of the graph) is substantially constant during the erosion of the film, and even during the erosion of the substrate, Although the numerical values are different, the wear depth per unit time is substantially constant. In the actual test, the predetermined specified time is set to 25 minutes in the test using WA # 8000 and 10 minutes in the test using WA # 320. It has been changed to 5 minutes. For convenience of illustration, in Comparative Example 1, in FIGS. 2 and 3A, the wear depth of the coating is shown by ▲ and the wear depth of the base material is shown by Δ every 25 minutes, and in FIG. 3B, The respective cross-sectional shapes at 0 minutes, 50 minutes, 100 minutes, 150 minutes, 200 minutes, 250 minutes, 300 minutes and 325 minutes are shown. In Example 1, in FIGS. 2 and 4A, the wear depth of the coating is indicated by ◆ and the wear depth of the base material is indicated by ◇ every 10 minutes, and in FIG. 4B, 0 minutes, 30 minutes The respective cross-sectional shapes at minutes, 60 minutes, 90 minutes, 120 minutes, 130 minutes and 135 minutes are shown. Then, as shown by the cross-sectional shape after 325 minutes after the start of the test shown in FIG. 3B and the cross-sectional shape after 135 minutes after the start of the test shown in FIG. 4B, the shape of the central portion in the cross-sectional shape is the same as before. The cross-sectional shape was measured by changing from the shape tendency (for example, changing from the arc shape tendency to the uneven shape in FIG. 4B), and from the erosion of the film, the erosion reached the base material and changed to the base material erosion. Understood from.

  From such measurement results, as shown in Table 1, in Comparative Example 1, the thickness of the coating was 6.39 μm, and the wear depth when the coating peeled from the base material (here, it reached the base material). The wear depth measured immediately before, the depth before reaching the base material in Table 1) is 5.86 μm, and the peeling start thickness S2 is 0.53 μm (= 6.39-5.86). I was asked. In Example 1, the thickness of the coating was 5.42 μm, and the wear depth when the coating peeled from the base material (here, the wear depth measured immediately before reaching the base material) was 4. It was 54 μm, and the peeling start thickness T2 was determined to be 0.88 μm (= 5.42-4.54).

  On the other hand, the wear depth measured immediately before reaching the base material may be the wear depth when the coating is peeled off from the base material, but the wear depth when the coating is peeled off from this base material is There is a concern that it will change depending on the experimental conditions (slurry concentration, erosion time, etc.), and the wear depth measurement step (here, the cross-sectional shape measurement step) first performed after reaching the base material, and immediately before this There may be a case where the true wear depth exists when the coating film is peeled off from the base material between the performed wear depth measurement step (here, the cross-sectional shape measurement step). Therefore, the true wear depth in the case where the film is peeled off from the base material is estimated based on the graphs showing the relationship between the elapsed time from the start of wear and the wear depth shown in FIGS. 2, 3A and 4A. . More specifically, in each of Comparative Example 1 and Example 1, the first approximate straight line (for example, the straight line obtained by the least squares method) that approximates each wear depth Δ and ◇ in the base material is the film thickness in the test body. Time (that is, the position of the bonding interface between the coating and the base material, the position of the base material surface), and the test time when the first approximate straight line intersects with the position of the coating thickness (elapsed time from the start of wear). ) Was obtained as the estimated base material arrival time, and the wear depth at the estimated base material arrival time was peeled from the base material from the second approximation line approximating each wear depth ▲, ◆ in the coating. It is calculated as the true wear depth in some cases. Then, the estimated delamination start thickness is obtained by using the obtained true wear depth when the film is delaminated from the base material in the above-mentioned equation A. Thus, the peeling start thickness St2 of Comparative Example 1 estimated from the slope of the graph is 0.28 μm, and the peeling start thickness Tt2 of Example 1 estimated from the slope of the graph is 0.77 μm. Met. For example, in the case of Comparative Example 1 shown in FIGS. 2 and 3A, when the test time is x and the wear depth is y, the first approximate straight line is y = 0.0216x−0.5007, The second approximate straight line is y = 0.194x−0.0795, and the estimated base material arrival time obtained by substituting y = 6.39 into the first approximate straight line is x = 319.01. By substituting this into the second approximation straight line, the true wear depth is obtained as y = 6.11. Therefore, as described above, the peeling start thickness St2 of Comparative Example 1 estimated from the slope of the graph is 6.39−6.11 = 0.28 μm.

  In the above description, since the abrasion (erosion) due to the particles (abrasive particles) is essentially controlled by the projection amount of polygonal particles contained in the liquid material, the elapsed time is the projection of particles. It may be the amount. The projection amount is the total mass of the projected particles, and is calculated by measuring the slurry flow rate during the projection and multiplying the measured slurry flow rate by the slurry concentration and the projection time. The projection time required for the total projection amount differs depending on the slurry flow rate and the slurry concentration. Further, the test time can be shortened by changing the slurry flow rate and the slurry concentration, and it is preferable to change the slurry flow rate and the slurry concentration depending on the film thickness of the target coating and the erosion rate (wear rate).

  From these, in Comparative Example 1, the peeling start thickness S2 obtained by using the wear depth measured immediately before reaching the base material was 0.53 μm, and the peeling start estimated from the slope of the graph was obtained. Since the thickness St2 is 0.28 μm, the error is about + 89% (≈ ((0.53-0.28 / 0.28) × 100), which is very large. In 1, the peel start thickness T2 obtained using the wear depth measured immediately before reaching the base material is 0.88 μm, and the peel start thickness Tt2 estimated from the slope of the graph is Since it is 0.77 μm, the error is about + 14% (≈ ((0.88−0.77 / 0.77) × 100), which is superior to Comparative Example 1. From the comparison of such errors, the evaluation with the particles of # 320 is as described above. Without seeking the wear depth of relaxin it is also understood that the in substrate to be measured immediately before reaching the wear depth can be evaluated sufficiently degree of adhesion.

  Further, in Comparative Example 1, it took 300 minutes to reach the substrate due to the erosion of the coating, and the test time was more than twice as long as 130 minutes in Example 1, so that WA # 8000 was used. Comparative Example 1 using the particles of No. 1 is not realistic, and in comparison, Example 1 using the particles of WA # 320 can perform the measurement quickly and stably.

(Examples 2 to 8)
Examples 2 to 8 are examples in which the type of base material is changed and the present evaluation method is compared with the conventional evaluation method.

  More specifically, as shown in Table 2, the base material of the test bodies in Examples 2 and 7 is cemented carbide (P type), and the base material of the test body in Example 3 is high. Speed tool steel (SKH51), the base material of the test body in Example 4 is a titanium alloy (Ti-6Al-4V), and the base material of the test body in Examples 5 and 8 is pure copper. The base material of the test body in Example 6 is pure titanium. Each film of each test body in Examples 2 to 8 was AlCrN and was formed by the PVD method. Examples 2 through 6, Example 7 and Example 8 were formed in two batches. The conditions other than these film forming times were all the same, and the film forming time was set long in order to increase the film thickness only in the batches of Example 7 and Example 8. There is no difference in nature.

  The present evaluation method for each test body in Examples 2 to 8 is the same as that in Example 1. On the other hand, the conventional evaluation method is a scratch test generally used as an adhesion evaluation method.

  In the scratch test for each of the test bodies in Examples 2 to 8, a scratch tester (CSEM REVERTEST SCRATCH TESTER) was used, and the scratch test was performed at a load of 0 N to 100 N and a test distance of 10 mm. From the state of scratch marks after the scratch test, the load at the point where the partial film peeling started was Lc2, and the load at the point where the film at the contact site all started peeling was Lc3. Note that in the test body of Example 7, peeling was not observed even when the load reached 100 N in the scratch test, so Lc2 and Lc3 are set to 100 N for convenience.

  Table 2 and FIG. 6 show the results of the present evaluation method and the conventional evaluation method for each of the test bodies in Examples 2 to 8. FIG. 6 is a diagram for explaining the relationship between Examples 2 to 8 and the scratch test results. FIG. 6A shows the relationship between the peeling start thickness and the peeling load Lc2, the horizontal axis thereof is the peeling start thickness expressed in μm, and the vertical axis thereof is the peeling load Lc2 expressed in N units. FIG. 6B shows the relationship between the peeling start thickness and the peeling load Lc3, the horizontal axis thereof is the peeling start thickness expressed in μm, and the vertical axis thereof is the peeling load Lc3 expressed in N units. For Example 7 in which the peeling loads Lc2 and Lc3 exceed 100 N, an upward arrow indicating that the peeling loads exceed 100 N is added to the plot.

  As can be seen from Table 2 and FIG. 6, the present evaluation method correlates with the conventional evaluation method, and peeling is likely to occur in the conventional evaluation method, that is, in the test body with a small load Lc2, the present evaluation method is used. On the other hand, the peeling starting thickness of No. 2 is large, and on the other hand, peeling hardly occurs by the conventional evaluation method, that is, the peeling starting thickness by this evaluation method is small in the test body having a large load Lc2. In addition, even if the scratch tester of the conventional evaluation method could not evaluate the test sample with good adhesion as in Example 7 (= the test sample with the peeling load Lc2 or the peeling load Lc3 exceeding 100 N), the peeling start thickness Can be measured and can be evaluated by this evaluation method.

  As described above, the present material adhesion evaluation method uses a liquid material containing polygonal particles to reduce the amount of material having at least the interface between the first portion and the second portion, and the peeling at the interface is started. Since the peeling start thickness, which is the remaining thickness of the first portion at that time, is used as an index of the adhesiveness, the adhesiveness at the interface can be evaluated more appropriately.

  In order to represent the present invention, the present invention has been described above appropriately and sufficiently through the embodiments with reference to the drawings, but those skilled in the art can easily modify and / or improve the embodiments. It should be recognized that this is possible. Therefore, unless a modification or improvement carried out by a person skilled in the art is at a level that deviates from the scope of rights of the claims recited in the claims, the modification or the improvement is covered by the scope of rights of the claims. Is understood to be included in.

Claims (3)

An injection step of injecting a liquid material containing polygonal particles onto the surface of the material to be evaluated having at least the interface between the first portion and the second portion,
A peeling start thickness that is the remaining thickness of the first portion when peeling at the interface is started, and a measurement step of measuring as a degree of adhesion representing the degree of adhesion at the interface,
Material adhesion evaluation method. The particles are hard particles having an average particle size of 40 μm or more,
The material adhesion evaluation method according to claim 1. The particles are hard particles having a HV of 1500 or more,
The material adhesion evaluation method according to claim 1.