JP5692007B2 - Thermal spray coating quality evaluation method - Google Patents

Description

  The present invention relates to a method for evaluating the quality of a sprayed coating, and more particularly to a technique for evaluating the film forming quality of a component to be inspected whose surface is coated with a sprayed coating.

  Conventionally, as a surface treatment method, thermal spraying is used in which a material called a thermal spray material is sprayed on a base material to form a thermal spray coating. As an example of thermal spraying, there is a cold spray method in which a thermal spray material is accelerated in a high-speed gas flow at a temperature lower than its melting point and collides with a base material at a high speed to form a film, and an apparatus used therefor Is also known (see, for example, Patent Document 1).

JP 2010-142669 A

In the surface treatment by thermal spraying such as the cold spray method, at present, the film quality can be improved only by destructive tests such as cross-sectional observation of the film by cutting inspection of the substrate on which the film is formed and peeling test of the film from the substrate. Could not be guaranteed. For this reason, it was not possible to inspect the film formation quality by 100% inspection.
In particular, according to the cold spray method, the spray material powder is sprayed onto the surface of the base material in the solid state, which may cause clogging at the tip of the spray gun, etc., and guarantee the quality of the coating. The necessity was high.

  Therefore, in view of the above situation, the present invention provides a thermal spray coating quality evaluation method that enables nondestructive evaluation of the film formation quality of a component to be inspected whose surface is coated with a thermal spray coating. It is.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

That is, in claim 1, there is provided a thermal spray coating quality evaluation method for evaluating the film formation quality of a component to be inspected whose surface is coated with a thermal spray coating, wherein the surface of the substrate is formed by a thermal spray coating, respectively. In a plurality of preliminary inspection target parts coated under different coating conditions, the adhesion strength measuring step of measuring the adhesion strength of the thermal spray coating to the base material, and the surface of the base material depending on the thermal spray coating, respectively in the different coating conditions A preliminary detection step of applying a preliminary electromagnetic signal to the plurality of covered preliminary inspection target parts and detecting a preliminary detection signal generated in the preliminary inspection target part by the preliminary electromagnetic signal, and the covering condition corresponds to From the relationship between the adhesion strength measured in the adhesion strength measurement step and the preliminary detection signal detected in the preliminary detection step in the preliminary inspection target part, a calibration curve is created. A calibration curve created in the calibration curve creation step, a calibration curve created step, a detection step of applying an electromagnetic signal to the inspection target component and detecting a detection signal generated in the inspection target component by the electromagnetic signal, a detection signal detected by the detecting step, from the relation of, by calculating the adhesive strength with respect to the base material of the thermal spray coating, to evaluate the deposition quality in the component being tested, and an evaluation step, the group The material is formed of a non-magnetic material, and in the preliminary detection step, two types of preliminary electromagnetic signals having different frequencies are applied to the surface of the preliminary inspection target part that is not covered with the thermal spray coating, An output difference between two types of signals generated in the preliminary inspection target component by the preliminary electromagnetic signal according to the frequency is detected as the preliminary detection signal, and in the detection step, the inspection pair Two kinds of electromagnetic signals having different frequencies are applied to the surface of the part that is not coated with the thermal spray coating, and the output difference between the two kinds of signals generated in the inspection target part by the electromagnetic signals according to the respective frequencies. Is detected as the detection signal .

The base material of the thermal spray coating according to claim 2 , in the preliminary inspection target part under a predetermined reference temperature condition and a comparative temperature condition different from the reference temperature condition in the adhesion strength measurement step and the preliminary detection step. Measuring the adhesion strength to the sensor, detecting a preliminary detection signal, and in the calibration curve creating step, the adhesion strength measured in the adhesion strength measurement step in the preliminary inspection target part corresponding to the coating condition, and the preliminary detection Based on the relationship between the preliminary detection signal detected in the process and the reference calibration curve under the reference temperature condition and the comparison calibration curve under the comparison temperature condition, the temperature difference between the reference temperature condition and the comparison temperature condition Based on the positional relationship between the reference calibration curve and the comparative calibration curve, the calibration is performed by performing a correction to translate the reference calibration curve in accordance with the temperature condition of the detection step. It is intended to create.

The method of claim 3, wherein the quality of the thermal spray coating is evaluated by evaluating the film deposition quality of a part to be inspected whose surface is coated with a thermal spray coating. The adhesion strength measuring step for measuring the adhesion strength of the thermal spray coating to the base material in a plurality of preliminary inspection target parts coated under conditions, and the surface of the base material are coated with the thermal spray coating under different coating conditions. In addition, a first preliminary electromagnetic signal is applied to both sides of the surface of the plurality of preliminary inspection target parts coated with the thermal spray coating and the uncoated side, and the first preliminary electromagnetic signal A first preliminary detection step of detecting a difference in signal output generated on each surface of the preliminary inspection target part as a first preliminary detection signal, and the preliminary inspection target part corresponding to the covering condition. From the relationship between the adhesion strength measured in the adhesion strength measurement step and the first preliminary detection signal detected in the first preliminary detection step, a first calibration curve creation step for creating a first calibration curve; A first electromagnetic signal is applied to both surfaces of the surface to be inspected, the side coated with the thermal spray coating and the side not coated, and each of the components to be inspected by the first electromagnetic signal. A first detection step of detecting a difference in signal output generated on the surface as a first detection signal, and a plurality of preliminary inspection target parts coated with different coating conditions on the surface of the substrate by a thermal spray coating. , Applying two types of second preliminary electromagnetic signals having different frequencies, and using the second preliminary electromagnetic signal at each frequency as an output difference between the two types of signals generated in the preliminary inspection target component as a second preliminary detection signal detection The second preliminary detection step, the adhesion strength measured in the adhesion strength measurement step in the preliminary inspection target part corresponding to the coating condition, the second preliminary detection signal detected in the second preliminary detection step, From the relationship, a second calibration curve is created, a second calibration curve creation step, and two types of second electromagnetic signals having different frequencies are applied to the inspection target component, and the second electromagnetic signals according to the respective frequencies are applied. A second detection step of detecting an output difference between two types of signals generated in the inspection target component as a second detection signal, and when the base material is a nonmagnetic material, the surface of the base material is formed by a thermal spray coating. , Two types of third preliminary electromagnetic signals having different frequencies are applied to the surface of the plurality of preliminary inspection target parts coated under different coating conditions, on the side not coated with the thermal spray coating, A third preliminary detection step of detecting, as a third preliminary detection signal, an output difference between the two types of signals generated in the preliminary inspection target component by the third preliminary electromagnetic signal according to frequency; and the preliminary corresponding to the covering condition Creating a third calibration curve based on the relationship between the adhesion strength measured in the adhesion strength measurement step and the third preliminary detection signal detected in the third preliminary detection step in the part to be inspected. And applying two types of third electromagnetic signals having different frequencies to the surface of the part to be inspected that is not coated with the thermal spray coating, and applying the third electromagnetic signal at each frequency to the part to be inspected. A third detection step of detecting an output difference between two types of generated signals as a third detection signal, a relationship between the first calibration curve and the first detection signal, the second calibration curve and the second detection signal signal The adhesion strength of the thermal spray coating to the substrate is calculated from at least two of the relationship between the third calibration curve and the third detection signal. An evaluation process for evaluating film quality.

In Claim 4, it is a quality evaluation method of the thermal spray coating which evaluates the film-forming quality of the components to be inspected whose surface is coated with the thermal spray coating, and the coating conditions of the thermal spray coating are different from each other. A first electromagnetic signal is applied to both surfaces of the surface to be inspected, the side coated with the sprayed coating and the side not coated, and each surface of the component to be inspected by the first electromagnetic signal. Two types of second electromagnetic signals having different frequencies for the first detection step for detecting the output difference of the signal generated as a first detection signal and the plurality of parts to be inspected having different coating conditions for the thermal spray coating. And a second detection step of detecting, as a second detection signal, an output difference between the two types of signals generated in the inspection target component by the second electromagnetic signal at each frequency, Two types of third electromagnetic signals having different frequencies are applied to the side of the surface of the plurality of parts to be inspected that are different from each other in the coating conditions of the thermal spray coating when the material is a coating material, A third detection step of detecting an output difference between two types of signals generated in the inspection target component by the third electromagnetic signal at each frequency as a third detection signal; and the first detection signal and the second detection signal And a first coordinate axis indicating one of the two signals of the third detection signal, and a second coordinate axis orthogonal to the first coordinate axis and indicating the other of the two signals. Using a coordinate plane, based on the distribution of points on the coordinate plane determined from the values of the two signals, an allowable error area in the coordinate plane is set in advance, and determined from the values of the two signals Points on the target plane, by whether it is in the allowable error region, to evaluate the deposition quality in the component being tested, those comprising an evaluation step.

  As effects of the present invention, the following effects can be obtained.

  According to the present invention, it is possible to nondestructively evaluate the film forming quality of a component to be inspected whose surface is coated with a thermal spray coating.

(A) is the perspective view which showed the test object components, (b), (c) is an enlarged view of the part which coat | covered the base material with the sprayed coating, respectively. (A) is the schematic which showed the process of measuring the adhesive strength with respect to the base material of a thermal spray coating, (b) is the schematic which showed the process of detecting the detection signal generate | occur | produced in components to be examined by an electromagnetic signal. (A), (b) is the schematic which showed the sensor which concerns on 1st Example and 2nd Example, respectively. (A) The schematic which showed the sensor which concerns on 3rd Example, (b) is the figure which showed the preparation method of a calibration curve. The figure which showed the quality evaluation method which concerns on 1st embodiment. (A) is the figure which showed the output value in the quality evaluation method which concerns on 1st embodiment, (b) is the figure which showed the output difference in the quality evaluation method which concerns on 1st embodiment similarly. (A) is the figure which showed the quality evaluation method which concerns on 2nd embodiment, (b) is the figure which similarly showed the difference result of the eddy current in the quality evaluation method which concerns on 2nd embodiment. The figure which shows the relationship between the alternating current excitation signal and detection signal in eddy current measurement. (A) is the figure which showed the quality evaluation method which concerns on 3rd embodiment, (b) is the figure which similarly showed the difference result of the eddy current in the quality evaluation method which concerns on 3rd embodiment. (A), (b) is the figure which showed the correction method of the calibration curve, respectively. The figure which showed the quality evaluation method which concerns on 4th embodiment. The figure which shows the example of a measurement result of a 1st detection signal and a 2nd detection signal in the quality evaluation method which concerns on 5th embodiment.

Next, embodiments of the invention will be described.
It should be noted that the technical scope of the present invention is not limited to the following examples, but broadly covers the entire scope of the technical idea that the present invention truly intends, as will be apparent from the matters described in the present specification and drawings. It extends.

[Part W to be inspected]
An inspection target component W that is an object of film formation quality evaluation in the present invention will be described with reference to FIGS. Note that the configuration of the preliminary inspection target component W described later is substantially the same as the configuration of the inspection target component W.
As shown in FIG. 1A, the inspection target component W is coated with a coating F (hereinafter simply referred to as “thermal spray coating”) F by spraying the surface of the base material B. Specifically, the thermal spray coating F is formed by spraying a material called a thermal spray material such as metal or ceramics onto the base material B. In this embodiment, as one aspect of the thermal spraying method, the thermal spray material is accelerated at a temperature equal to or lower than its melting point and in a high-speed gas flow, and is collided with the base material B at a high speed to form the thermal spray coating F. The forming cold spray method is used. According to the cold spray method, since the sprayed coating F is formed under a low temperature condition as compared with normal spraying, it is possible to reduce changes in material properties due to heat and oxidation in the sprayed coating F. .

The thermal spray coating F formed by the cold spray method has a difference in film formation quality depending on the set pressure applied to the thermal spray material by the cold spray apparatus.
Specifically, description will be made with reference to FIGS. The inspection target part Wh in FIG. 1B is obtained by increasing the set pressure of the cold spray device as compared with the inspection target part Wl in FIG. As shown in FIGS. 1B and 1C, the sprayed coating Fh on the inspection target component Wh has a larger amount of particle penetration at the interface with the base material Bh (Bl) than the sprayed coating Fl. For this reason, the anchor effect with respect to the base material Bh of the thermal spray coating Fh becomes larger than the anchor effect with respect to the base material Bl of the thermal spray coating Fl.

Further, the stress remaining in the thermal spray coating Fh is larger than that of the thermal spray coating Fl. Further, the inspection target component Wh is smaller than the inspection target component Wl in the thermal spray coating Fh (Fl) and at the interface between the thermal spray coating Fh (Fl) and the base material Bh (Bl).
Due to the difference between the inspection target component Wh and the inspection target component Wl, the adhesion strength of the thermal spray coating Fh to the base material Bh is larger than the adhesion strength of the thermal spray coating Fl to the base material Bl. As such adhesion strength, the lower limit strength required for the inspection target component W is determined in advance, and this lower limit is described as “lower limit strength” in this specification.

  As described above, the difference in adhesion strength between the thermal spray coating F and the base material B is also affected by the gap and residual stress generated in the thermal spray coating F and at the interface between the thermal spray coating F and the base material B. The thermal spray coating quality evaluation method according to the present invention detects non-destructive inspection by detecting differences in electromagnetic characteristics such as permeability and conductivity based on differences in gaps and residual stresses in the inspection target component W. This is used for evaluating the film formation quality of the thermal spray coating F on the target component W.

[Adhesion strength measurement process]
Next, the quality evaluation method according to the first embodiment will be described with reference to FIGS.
In the quality evaluation method according to the present embodiment, first, in the adhesion strength measurement step, the adhesion of the thermal spray coating F to the substrate B in the preliminary inspection target component W, which is a plurality of level test pieces each having different coating conditions of the thermal spray coating F. Measure strength.

Specifically, in the present embodiment, as shown in FIG. 2A, a measurement jig R made of an epoxy resin is brought into close contact with the surface on which the thermal spray coating F is formed in the preliminary inspection target component W that is a level test piece. . Then, a force is applied to the measuring jig R to move it at a predetermined speed as indicated by an arrow A in FIG. Thus, the thermal spray coating F is peeled off from the base material B by moving the measuring jig R in close contact with the thermal spray coating F in the direction of arrow A.
Thereafter, a method of peeling the thermal spray coating F from the base material B is measured, and a so-called peeling test is performed in which the adhesion strength of the thermal spray coating F to the base material B is measured.

  In the adhesion strength measurement step in the present embodiment, the peeling test is used as described above, but other methods such as a cross-sectional observation of the sprayed coating F by cutting inspection of the preliminary inspection target component W that is a level test piece are used. It is possible to use. That is, other methods may be used as long as the adhesion strength of the thermal spray coating F to the base material B can be measured, and the specific method is not limited.

[Preliminary detection process]
Next, in the preliminary detection step, the preliminary electromagnetic signal PSi is applied to the preliminary inspection target component W, which is a plurality of level test pieces having different coating conditions of the thermal spray coating F, and is generated in the preliminary inspection target component W by the preliminary electromagnetic signal PSi. The preliminary detection signal PSo to be detected is detected.

  Specifically, as shown in FIG. 2 (b), a control device 21, which is a general-purpose computer, a voltmeter 22, an inspection device 23 having an AC power supply, and an inspection device 20 having a sensor 30 are provided as spares. Installed in the vicinity of the inspection target component W. Each part in the inspection apparatus 20 is electrically connected and configured to be communicable. The sensor 30 is arranged close to the preliminary inspection target component W.

Further, the inspector 23 controls the sensor 30 so that the preliminary electromagnetic signal PSi is applied to the preliminary inspection target component W and the preliminary detection signal PSo is detected from the preliminary inspection target component W. The preliminary detection signal PSo is measured by the voltmeter 22, and the measurement result is stored / calculated by the control device 21.
In the present embodiment, the preliminary detection process is performed after the adhesion strength measurement process, but the order may be reversed. That is, it is possible to adopt a configuration in which the adhesion strength measurement process is performed after the preliminary detection process.

[Sensor 30]
The sensor 30 has various aspects, and any of them can be used for the quality evaluation method according to the present embodiment. Hereinafter, the aspects of the respective sensors 30 will be described in the order from the first embodiment to the third embodiment with reference to FIGS. 3A, 3B, and 4A.
FIG. 3A shows a cubic sensor 30a used as the sensor 30 according to the first embodiment. The cubic sensor 30a is a so-called eddy current measuring sensor, and uses the relationship between the hardness and the permeability with respect to the distance from the surface in the preliminary inspection target component W.

  The cubic sensor 30a according to the present embodiment includes an excitation unit and a detection unit. The excitation unit applies a predetermined AC excitation signal, which is the preliminary electromagnetic signal PSi, in a state of being arranged to face the preliminary inspection target component W. The detection unit detects a preliminary detection signal PSo due to an eddy current generated in the preliminary inspection target component W by the excitation unit to which the AC excitation signal is applied.

The exciting part is configured by exciting coils 33a and 33a wound around a substantially cubic nonmagnetic bobbin 31a. Specifically, the exciting coils 33a and 33a are wound orthogonally so as to intersect the upper surface and the lower surface of the nonmagnetic bobbin 31a.
Both ends (both terminals) of the exciting coils 33 a and 33 a are connected to an AC power source of the inspection device 23. That is, the excitation coils 33a and 33a are excitation coils for applying a predetermined AC excitation signal to the preliminary inspection target component W.

The detection unit includes a detection coil 32a disposed on one of the lower sides of the two intersecting portions of the excitation coils 33a and 33a. The detection coil 32a is disposed substantially at the center of the lower intersection of the excitation coils 33a and 33a on the lower surface of the nonmagnetic bobbin 31a.
In the present embodiment, a thin film planar coil is used as the detection coil 32a, but other coils such as a pancake coil can also be used.
Both ends (both terminals) of the detection coil 32 a are connected to the inspection device 23. That is, the detection coil 32a detects the preliminary detection signal PSo due to the eddy current from the preliminary inspection target component W to which the AC excitation signal is applied.

  When the preliminary detection signal PSo in the preliminary inspection target component W is detected using the cubic sensor 30a configured as described above, the cubic sensor 30a is set in the standby position with the detection coil 32a facing the preliminary inspection target component W. A voltage is applied as a preliminary electromagnetic signal PSi to each of the exciting coils 33a and 33a by an AC power source in a state of being disposed close to the inspection target component W. At the moment when a current flows through the exciting coils 33a and 33a, a rotating magnetic field is generated according to the right-handed screw law as indicated by an arrow α1 in FIG. Then, electromagnetic induction is caused by this rotating magnetic field, and eddy current is generated in the preliminary inspection target component W by electromagnetic induction. Further, as an eddy current is generated on the surface of the preliminary inspection target component W, a magnetic flux is passed through the detection coil 32a, and an induced voltage is generated in the detection coil 32a. Then, the induced voltage is measured as the preliminary detection signal PSo by the detection coil 32a.

  According to the cubic sensor 30a according to the present embodiment, as described above, a horizontal magnetic field with small attenuation of magnetic field strength due to lift-off is generated without contacting the preliminary inspection target component W, and this horizontal magnetic field is detected by the preliminary detection signal PSo. Used for. For this reason, it becomes possible to reduce the influence of the lift-off from the preliminary inspection target component W of the cubic sensor 30a.

  FIG. 3B shows a U-core sensor 30b used as the sensor 30 according to the second embodiment. The U core sensor 30b is also an eddy current measuring sensor as in the cubic sensor 30a according to the first embodiment, and has substantially the same configuration except for its shape. For this reason, below, it demonstrates centering around difference with a 1st Example.

  The exciting part in the U-core sensor 30b according to the present embodiment is configured by winding an exciting coil 33b around a central part of a substantially U-shaped nonmagnetic bobbin 31b. The detection part is arrange | positioned in the intermediate position in the both front-end | tip parts of the lower side of the nonmagnetic bobbin 31b.

  When the preliminary detection signal PSo in the preliminary inspection target component W is detected using the U core sensor 30b configured as described above, the U core sensor 30b is set in the standby position with the detection coil 32b facing the preliminary inspection target component W. A voltage is applied as a preliminary electromagnetic signal PSi to the exciting coil 33b by an AC power source in a state of being disposed close to the inspection target component W. At the moment when a current flows through the exciting coil 33b, a magnetic field is generated according to the right-handed screw law as indicated by an arrow α2 in FIG. Then, electromagnetic induction is caused by this magnetic field, and eddy current is generated in the preliminary inspection target component W by electromagnetic induction. Further, as an eddy current is generated on the surface of the preliminary inspection target component W, a magnetic flux is passed through the detection coil 32b and an induced voltage is generated in the detection coil 32b. Then, the induced voltage is measured as the preliminary detection signal PSo by the detection coil 32b.

  Depending on the U core sensor 30b according to the present embodiment, the horizontal magnetic field generated in the preliminary inspection target component W can be converged without contacting the preliminary inspection target component W. For this reason, the output of the preliminary detection signal PSo can be increased to facilitate detection.

  FIG. 4A shows a potential difference sensor 30c used as the sensor 30 according to the third embodiment. The potential difference sensor 30c includes probe probes 31c and 31c in the so-called AC potential difference method, and uses the conductivity in the preliminary inspection target component W. The probe probes 31c and 31c are each connected to an AC power source of the tester 23.

  When detecting the preliminary detection signal PSo in the preliminary inspection target component W using the potential difference sensor 30c configured as described above, the probe probes 31c and 31c are arranged in contact with the preliminary inspection target component W. Then, a predetermined alternating voltage which is the preliminary electromagnetic signal PSi is applied. Then, the potential difference between the probe probes 31c and 31c caused by the current flowing through the preliminary inspection target component W as indicated by the arrow β in FIG. 4 by the AC voltage is detected as the preliminary detection signal PSo.

  According to the potential difference sensor 30c according to the present embodiment, since the conductivity in the preliminary inspection target component W is used as described above, the measurement principle is simple and only the electrical characteristics of the preliminary inspection target component W are measured. Is possible.

[Calibration curve creation process]
Next, in the calibration curve creation process, the calibration curve is determined from the relationship between the adhesion strength measured in the adhesion strength measurement process and the preliminary detection signal PSo detected in the preliminary detection process in the preliminary inspection target component W corresponding to the coating condition. Create L.

  Specifically, each point is plotted at a position corresponding to the adhesion strength and the preliminary detection signal PSo for each preliminary inspection target component W corresponding to the covering condition, as indicated by points P1 to P4 in FIG. 4B. To do. Thereafter, based on the plot positions from the points P1 to P4, the calibration curve L is created so that the calibration curve L passes through the vicinity of the points P1 to P4.

[Detection process]
Next, in the detection step, the electromagnetic signal Si is applied to the inspection target component W that is the inspection target, and the detection signal So generated in the inspection target component W is detected by the electromagnetic signal. In this detection step, the inspection device 20 is used to detect the detection signal So in the inspection target component W in place of the preliminary inspection target component W in the same manner as in the preliminary detection step. That is, the detection signal So is detected using the sensor 30 used in the preliminary detection step among the cubic sensor 30a, the U core sensor 30b, and the potential difference sensor 30c, which are the sensors 30 of the first to third embodiments. To do.

[Evaluation process]
Next, in the evaluation process, the adhesion strength of the thermal spray coating F to the base material B is calculated from the relationship between the calibration curve L created in the calibration curve creation process and the detection signal So detected in the detection process. The film formation quality in the part W is evaluated.

  Specifically, when the value of the detection signal So detected in the detection step is S1 shown in FIG. 4B, the point Q on the calibration curve L corresponding to S1 is taken and the adhesion strength corresponding to the point Q is taken. C1 is calculated as the adhesion strength of the thermal spray coating F to the base material B in the inspection target component W. Then, the film formation quality in the inspection target component W is evaluated based on whether or not the adhesion strength C1 is larger than the lower limit strength that is the lower limit required for the inspection target component W. Specifically, when the adhesion strength C1 is larger than the lower limit strength, the film forming quality is evaluated as “good”, and when the adhesion strength C1 is smaller than the lower limit strength, the film forming quality is evaluated as “bad”.

As described above, according to the quality evaluation method according to the present embodiment, it is possible to nondestructively evaluate the film formation quality in the inspection target component W in which the surface of the base material B is coated with the thermal spray coating F. For this reason, the film formation quality can be inspected by 100% inspection of the parts to be inspected W.
Further, in the cold spray method, since the spray material powder is sprayed onto the surface of the base material in a solid state, clogging may occur at the tip of the spray gun. For this reason, when inspecting the sprayed coating F by the cold spray method, it is particularly effective that the quality of the sprayed coating F can be guaranteed by 100% inspection.

[Detection signal So]
As described above, the quality evaluation method of the thermal spray coating according to the present embodiment is performed by using the gaps generated in the thermal spray coating F in the preliminary inspection target component W (test target component W) or the interface between the thermal spray coating F and the base material B. This is to detect a difference in electromagnetic characteristics such as permeability and conductivity based on a difference in residual stress. On the other hand, when there is a variation in the electromagnetic characteristics of the base material B for each preliminary inspection target component W (inspection target component W) or for each inspection target portion, the variation becomes noise and leads to a decrease in inspection accuracy. There is.

  For this reason, in the present embodiment, in the preliminary detection step and the detection step, as shown in FIG. 5, on the surface of the preliminary inspection target component W (inspection target component W) that is coated with the thermal spray coating F (in FIG. 5). The cubic sensor 30a is brought close to both the upper side and the uncovered side (lower side in FIG. 5), and the preliminary electromagnetic signal PSi (electromagnetic signal Si) is applied simultaneously or alternately. Then, an output difference between signals generated on the respective surfaces of the preliminary inspection target component W (inspection target component W) by the preliminary electromagnetic signal PSi (electromagnetic signal Si) is detected as a preliminary detection signal PSo (detection signal So). .

  Concretely, it demonstrates using FIG. 5, FIG. 6 (a) and (b). Output values D11 to D13 shown in FIG. 6 (a) are values detected on the side coated with the thermal spray coating F shown in FIG. 5, and output values D21 to D23 are thermal spray coating F shown in FIG. It is a value detected on the surface on the uncoated side. That is, the output values D11 to D13 are values reflecting the electromagnetic characteristics of the base material B itself in addition to the inside of the thermal spray coating F and the interface between the thermal spray coating F and the base material B. On the other hand, the output values D21 to D23 reflect only the electromagnetic characteristics of the base material B. Here, the output values D11 and D21, the output values D12 and D22, and the output values D13 and D23 are values detected in the same preliminary inspection target part W (inspection target part W) or inspection target part, respectively.

  Then, d1 which is the output difference between the output values D11 and D21 is set as the detection signal D31 in FIG. 6B, and similarly, d2 (d3) which is the output difference between the output values D12 (D13) and D22 (D23). Is the detection signal D32 (D33) in FIG. These detection signals D31 to D33 are detected as a preliminary detection signal PSo (detection signal So) in the preliminary detection step and the detection step.

  By configuring as described above, in addition to the interface between the thermal spray coating F and the thermal spray coating F and the base material B, the output values D11 to D13 reflecting the electromagnetic characteristics of the base material B itself, and the electromagnetism of the base material B The difference value between the output values D21 to D23 in which only the target characteristic is reflected is used as the preliminary detection signal PSo (detection signal So). As a result, even if the electromagnetic characteristics of the base material B itself (the magnetic permeability in this embodiment) vary for each preliminary inspection target part W (inspection target part W) or each inspection target part, the influence is offset. This can reduce noise components due to variations.

  In the drawings shown in FIG. 5 and subsequent figures, the sensor 30 is described as performing eddy current measurement using the cubic sensor 30a, but other sensors and inspection methods may be employed.

[Second Embodiment]
Next, the quality evaluation method according to the second embodiment will be described with reference to FIGS.
In the embodiments described below, the detailed description of the same configuration as that of the first embodiment will be omitted, and differences will be mainly described.

  As in the first embodiment, the thermal spray coating quality evaluation method according to the present embodiment is performed in the thermal spray coating F in the preliminary inspection target component W (test target component W) or the interface between the thermal spray coating F and the base material B. This is to detect a difference in electromagnetic characteristics such as magnetic permeability and conductivity based on a difference in gap and residual stress generated in the magnetic field. On the other hand, the surface portion of the thermal spray coating F (see the side opposite to the interface with the base material B, see FIGS. 1B and 1C) may be formed coarsely during thermal spraying. As described above, when the surface roughness of the thermal spray coating F varies for each preliminary inspection target component W (inspection target component W) or for each inspection target portion, the variation becomes noise and leads to a decrease in inspection accuracy. There is a case.

  For this reason, in the quality evaluation method according to the present embodiment, in the preliminary detection step and the detection step, two types of preliminary electromagnetic signals PSi (electromagnetic signals Si) having different frequencies are applied to the preliminary inspection target component W (inspection target component W). It is set as the structure to apply. Then, an output difference between two types of signals generated in the preliminary inspection target component W (inspection target component W) by the preliminary electromagnetic signal PSi (electromagnetic signal Si) at each frequency is detected as a preliminary detection signal PSo (detection signal So). To do.

  Concretely, it demonstrates using FIG. 7 (a), (b), and FIG. In the present embodiment, in the preliminary detection step and the detection step, as shown in FIG. 7A, the excitation frequency is low on the surface of the preliminary inspection target component W (the inspection target component W) covered with the thermal spray coating F. The cubic sensor 30a (left side in FIG. 7 (a)) and the high-frequency cubic sensor 30a (right side in FIG. 7 (a)) are brought close to each other, and the preliminary electromagnetic signal PSi (electromagnetic signal Si) is applied simultaneously or alternately. It is.

  Here, the penetration depth δ of the eddy current is given by Equation 1 below. In Equation 1, f, μ, and σ represent the excitation frequency, the magnetic permeability and the electrical conductivity of the object, respectively.

  As shown in Equation 1, as the excitation frequency f increases, the penetration depth δ decreases. That is, the penetration depth δ of the eddy current by the cubic sensor 30a having a high excitation frequency is shallower than that of the cubic sensor 30a having a low excitation frequency, as shown on the right side in FIG. Note that the “penetration depth” of eddy current in this specification means “depth at which the strength of eddy current is about 37% of the surface of the object”.

  As described above, the eddy current penetration depth δ is different between the cubic sensor 30a having a low excitation frequency and the cubic sensor 30a having a high frequency. That is, by adjusting the penetration depth δ of the eddy current, not only in the sprayed coating F in the preliminary inspection target component W (test target component W) and the interface between the thermal spray coating F and the base material B, but also the surface roughness. It is possible to detect a difference in electromagnetic characteristics only at the surface portion where the sapphire appears.

  Then, as shown in FIG. 7 (b), the difference in output between the two types of signals generated in the preliminary inspection target component W (inspection target component W) is set as a difference result Fd, so that the preliminary detection signal PSo ( It is detected as a detection signal So). Thereby, even if the surface roughness of the thermal spray coating F varies for each preliminary inspection target part W (inspection target part W) or for each inspection target part, the influence can be offset and the noise component due to the variation can be reduced. Is possible.

[Difference result Fd]
A method of calculating the difference result Fd will be described with reference to FIG. As shown in FIG. 8, the AC power supply of the tester 23 applies a predetermined AC excitation signal (excitation AC voltage signal) V1 to the excitation coil 33a. The inspector 23 detects the magnitude of the detection signal (voltage signal for the induced voltage) V2 obtained from the detection coil 32a when the AC excitation signal V1 from the AC power source is applied to the excitation coil 33a, and the AC of the detection signal V2. A phase difference (phase delay) Φ with respect to the excitation signal V1 is detected. Here, in order to detect the phase difference Φ, the AC excitation signal V1 (waveform) is given to the inspector 23 as the amplified phase detection.

  The detection signal V2 detected by the detection coil 32a reflects the magnetic permeability of the preliminary inspection target component W (inspection target component W). That is, when the permeability of the measurement site 6a increases, the magnetic flux accompanying the generation of the eddy current as described above increases and the detection signal V2 increases. Conversely, when the permeability of the preliminary inspection target component W (inspection target component W) decreases, the magnetic flux associated with the generation of eddy current decreases and the detection signal V2 decreases. In order to quantify (numerize) the detection signal V2 based on this eddy current, the amplitude value Y, which is the magnitude of the detection signal V2, and a value resulting from the phase difference Φ of the detection signal V2 with respect to the AC excitation signal V1. A certain value X (= Y cos Φ) is defined.

  Here, the difference result Fd is given by Equation 2 below. Xa and Ya in Equation 2 represent a value X and an amplitude value Y caused by the phase difference Φ measured by the cubic sensor 30a having a deep eddy current penetration depth δ and a low excitation frequency, respectively. . Further, Xb and Yb respectively represent a value X and an amplitude value Y caused by the phase difference Φ measured by the cubic sensor 30a having a shallow eddy current penetration depth δ and a high excitation frequency.

[Third embodiment]
Next, the quality evaluation method according to the third embodiment will be described with reference to FIGS.
The base material B in the preliminary inspection target component W (inspection target component W), which is the target of the thermal spray coating quality evaluation method according to the present embodiment, is formed of a nonmagnetic material. In the quality evaluation method according to the present embodiment, in the preliminary detection step and the detection step, the surface of the preliminary inspection target component W (inspection target component W) that is not covered with the thermal spray coating F (upper side in FIG. 9). In other words, two types of preliminary electromagnetic signals PSi (electromagnetic signals Si) having different frequencies are applied to the side of the base material B which is a nonmagnetic material. Then, an output difference between two types of signals generated in the preliminary inspection target component W (inspection target component W) by the preliminary electromagnetic signal PSi (electromagnetic signal Si) at each frequency is detected as a preliminary detection signal PSo (detection signal So). To do.

  Specifically, this will be described with reference to FIG. In the present embodiment, in the preliminary detection step and the detection step, a cubic sensor 30a having a low excitation frequency on the surface of the preliminary inspection target component W (inspection target component W) that is not covered with the thermal spray coating F (FIG. 9 ( The left side in a) and the high-frequency cubic sensor 30a (right side in FIG. 9A) are brought close to each other, and the preliminary electromagnetic signal PSi (electromagnetic signal Si) is applied simultaneously or alternately.

  As described above, since the penetration depth δ decreases as the excitation frequency f increases, the penetration depth δ of the eddy current by the cubic sensor 30a having a high excitation frequency is excited as shown on the right side in FIG. The frequency becomes shallower than that of the low frequency cubic sensor 30a. At this time, since the base material B is made of a nonmagnetic material, a sufficient eddy current can be penetrated to the side covered with the thermal spray coating F as shown in FIG. .

  As described above, the eddy current penetration depth δ is different between the cubic sensor 30a having a low excitation frequency and the cubic sensor 30a having a high frequency. That is, it is possible to measure the penetration depth to the thermal spray coating F with the low frequency cubic sensor 30a and measure the penetration depth to the base material B with the high frequency cubic sensor 30a.

  Then, as shown in FIG. 9B, the preliminary detection signal PSo (detection) in the preliminary detection step and the detection step is obtained by using the output difference between the two types of signals generated in the preliminary inspection target component W (inspection target component W) as a difference result. It is detected as a signal So). Thereby, the detection result only in the sprayed coating F in the preliminary test target component W (test target component W) or only the interface between the sprayed coating F and the base material B can be obtained. Note that the method of calculating the difference result between the two types of signals in the present embodiment is the same as the method in the second embodiment, and a detailed description thereof will be omitted.

  As described above, in the present embodiment, by measuring from the base material B side, the preliminary inspection target component W (() is not affected by variations in the surface roughness of the thermal spray coating F or the electromagnetic characteristics of the base material B. It is possible to detect a difference in electromagnetic characteristics in the sprayed coating F in the inspection target component W) or only at the interface between the sprayed coating F and the base material B.

[Calibration method for calibration curve]
Next, a calibration curve correction method will be described with reference to FIG.
When correcting the calibration curve, in the adhesion strength measurement step and the preliminary detection step, a predetermined reference temperature condition (20 degrees in this embodiment) and a comparison temperature condition different from the reference temperature condition (in this embodiment) In addition to measuring the adhesion strength of the thermal spray coating F to the base material B in the preliminary inspection target part W at 35 degrees and 5 degrees), a preliminary detection signal is detected.

  Then, in the calibration curve creation step, the reference temperature condition is determined based on the relationship between the adhesion strength measured in the adhesion strength measurement step and the preliminary detection signal detected in the preliminary detection step in the preliminary inspection target component W corresponding to the coating condition. And a standard calibration curve L1 and L2 under comparative temperature conditions are created. Specifically, as shown in FIG. 10A, a calibration curve at a reference temperature is created as a reference calibration curve L0, and a comparative calibration curve at a temperature higher than the reference temperature (35 degrees in the present embodiment) is L1. A comparative calibration curve at a temperature lower than the temperature (5 degrees in this embodiment) is created as L2.

Then, based on the temperature difference between the reference temperature condition and the comparison temperature condition, and the positional relationship between the reference calibration curve L0 and the comparison calibration curves L1 and L2, the reference calibration curve L0 is paralleled corresponding to the temperature condition of the detection process. A calibration curve Lr is created by performing correction for movement.
Specifically, as shown in FIG. 10A, from the temperature rise (15 degrees) and the positional relationship between the reference calibration curve L0 and the comparative calibration curve L1, the calibration curve associated with the temperature change as shown by the arrow Rh. The amount of movement is calculated. Similarly, the amount of movement of the calibration curve according to the temperature change is calculated from the temperature drop (15 degrees) and the respective positional relationships in the reference calibration curve L0 and the comparative calibration curve L2, as shown by the arrow Rl. Then, when the temperature condition of the detection process is, for example, 12 degrees, the reference calibration curve L0 is corrected to be translated downward by a movement amount R corresponding to minus 8 degrees (12 degrees-reference temperature condition 20 degrees), A calibration curve Lr is created.

  As described above, by correcting the calibration curve L corresponding to the temperature condition in the detection step, it is possible to reduce the influence of the temperature change on the measurement using the electromagnetic characteristics. That is, even when the temperature in the detection process changes depending on the season or weather, it is possible to create a calibration curve L corresponding to the temperature condition at that place, and therefore, there is no influence.

  When the calibration curve L is created as described above, as shown in FIG. 10B, adjustment is made so that the preliminary detection signal becomes zero in the preliminary inspection target component W whose adhesion strength is “lower limit strength” (zero adjustment). It is preferable to do. By performing zero adjustment in this way, the adhesion strength C1 calculated from the detection signal and the lower limit strength can be compared only by numerical value positive / negative judgment, so that the evaluation of the film formation quality of the inspection target component W in the evaluation process can be easily performed. Can be done.

[Fourth embodiment]
Next, the quality evaluation method according to the fourth embodiment will be described with reference to FIG.
The thermal spray coating quality evaluation method according to the present embodiment evaluates the film formation quality of the inspection target component W in which the surface of the base material B is coated with the thermal spray coating F, as in the described embodiment.
And similarly to 1st embodiment, the adhesion strength measurement process of measuring the adhesion strength with respect to the base material B of the thermal spray coating F in the some pre-inspection object W from which the coating conditions of the thermal spray coating F differ is provided.

Similarly to the first embodiment, among the surfaces of the plurality of preliminary inspection target parts W having different coating conditions, both the side coated with the thermal spray coating F and the side not coated are first A first preliminary detection step of applying a preliminary electromagnetic signal PSi and detecting, as a first preliminary detection signal PSo, an output difference between signals generated on the respective surfaces of the preliminary inspection target component W by the first preliminary electromagnetic signal PSi; .
Furthermore, from the relationship between the adhesion strength measured in the adhesion strength measurement step and the first preliminary detection signal PSo detected in the first preliminary detection step in the preliminary inspection target component W corresponding to the coating condition, the first calibration curve is obtained. A first calibration curve creating step is provided.
Then, the first electromagnetic signal Si is applied to both sides of the surface of the inspection target component W that is coated with the thermal spray coating F and the non-coated side, and the inspection target component is detected by the first electromagnetic signal Si. A first detection step of detecting an output difference between signals generated on each surface of W as a first detection signal So;

Similarly to the second embodiment, two types of second preliminary electromagnetic signals PSi having different frequencies are applied to a plurality of preliminary inspection target parts W having different coating conditions, and the second preliminary electromagnetic signals PSi corresponding to the respective frequencies are applied. A second preliminary detection step of detecting an output difference between the two types of signals generated in the preliminary inspection target component W as a second preliminary detection signal PSo.
Further, the second calibration curve is obtained from the relationship between the adhesion strength measured in the adhesion strength measurement process and the second preliminary detection signal PSo detected in the second preliminary detection process in the preliminary inspection target component W corresponding to the coating condition. A second calibration curve creating step is prepared.
Then, two types of second electromagnetic signals Si having different frequencies are applied to the inspection target component W, and an output difference between the two types of signals generated in the inspection target component W by the second electromagnetic signals Si at the respective frequencies is A second detection step of detecting as the two detection signals So is provided.

Similarly to the third embodiment, when the base material B is a nonmagnetic material, the frequency on the side not covered with the thermal spray coating F among the surfaces of the plurality of preliminary inspection target parts W having different coating conditions. Are applied as two types of third preliminary electromagnetic signals PSi, and the output difference between the two types of signals generated in the preliminary inspection target component W by the third preliminary electromagnetic signals PSi at the respective frequencies is defined as a third preliminary detection signal PSo. A third preliminary detection step for detecting is provided.
Further, from the relationship between the adhesion strength measured in the adhesion strength measurement process and the third preliminary detection signal PSo detected in the third preliminary detection process in the preliminary inspection target component W corresponding to the coating condition, a third calibration curve is obtained. A third calibration curve creating step is prepared.
Then, two types of third electromagnetic signals Si having different frequencies are applied to the surface of the inspection target component W that is not covered with the thermal spray coating F, and the inspection target component W is generated by the third electromagnetic signal Si of each frequency. A third detection step of detecting an output difference between the two types of signals generated in the second detection signal So as a third detection signal So.

  In addition, at least two of the relationship between the first calibration curve and the first detection signal, the relationship between the second calibration curve and the second detection signal, and the relationship between the third calibration curve and the third detection signal From the relationship, the adhesion strength of the thermal spray coating F to the base material B is calculated, and an evaluation process for evaluating the film formation quality in the inspection target component W is provided.

  In FIG. 11, two types of second preliminary electromagnetic signals PSi (electromagnetic signals Si) having different frequencies are applied to the surface of the preliminary inspection target component W (inspection target component W) coated with the thermal spray coating F, and the second In the second preliminary detection step (second detection step) for detecting the preliminary detection signal PSo (second detection signal So) and on the surface not covered with the thermal spray coating F of the preliminary inspection target component W (inspection target component W). A third preliminary detection step (third detection step) for detecting a third preliminary detection signal PSo (third detection signal So) by applying two types of third preliminary electromagnetic signals PSi (electromagnetic signal Si) having different frequencies. ) Are performed simultaneously.

  As described above, in this embodiment, the quality evaluation method according to the first to third embodiments is combined to evaluate the film formation quality of the preliminary inspection target component W (inspection target component W). . In this way, by combining a plurality of types of quality evaluation methods, it is possible to improve the evaluation accuracy of the film formation quality in the inspection target component W.

  In the present embodiment, two types of quality evaluation methods are combined. However, three types of quality evaluation methods may be combined. In this case, the film forming quality of the inspection target component W that is determined to be “good” by the evaluation using two or more types of quality evaluation methods is finally determined to be “good”.

[Fifth embodiment]
Next, the quality evaluation method according to the fifth embodiment will be described with reference to FIG.
The thermal spray coating quality evaluation method according to the present embodiment evaluates the film formation quality of the inspection target component W in which the surface of the base material B is coated with the thermal spray coating F, as in the described embodiment.

  And like 1st embodiment, it is on both surfaces with the side coat | covered with the sprayed coating F among the surfaces in the some test object W from which the coating conditions of the sprayed coating F differ, respectively, and the side which is not coat | covered. And a first detection step of applying a first electromagnetic signal Si and detecting an output difference between signals generated on the respective surfaces of the inspection target component W by the first electromagnetic signal Si as a first detection signal So.

  In addition, two types of second electromagnetic signals Si having different frequencies are applied to a plurality of inspection target parts W having different coating conditions of the thermal spray coating F, and are generated in the inspection target part W by the second electromagnetic signals Si having the respective frequencies. A second detection step of detecting an output difference between the two types of signals to be detected as the second detection signal So.

  Furthermore, when the base material B is a non-magnetic material, two types having different frequencies are provided on the surface of the plurality of parts to be inspected W having different coating conditions of the spray coating F on the side not covered with the spray coating F. A third detection step of applying a third electromagnetic signal Si and detecting, as a third detection signal So, an output difference between the two types of signals generated in the inspection target component W by the third electromagnetic signal Si at each frequency. Prepare.

  In the evaluation step, the first coordinate axis indicating one of the two signals of the first detection signal, the second detection signal, and the third detection signal, and two orthogonal to the first coordinate axis Using a coordinate plane defined by the second coordinate axis indicating the other of the signals, based on the distribution of points on the coordinate plane determined from the values of the two signals, an allowable error region in the coordinate plane is set in advance, The film forming quality of the inspection target component is evaluated based on whether or not the point on the coordinate plane determined from the signal value is within the allowable error region.

An evaluation method in the evaluation process will be described with reference to FIG.
As shown in FIG. 12, first, from the distribution of the points on the coordinate plane determined from the values of the two signals, the direction of the first principal component (long-axis direction) that is the component that has the highest contribution rate to the distribution of many good data ) When the direction of the first main component is obtained, the direction (short axis direction) of the second main component is determined as the direction orthogonal to the direction.

  The directions of the first principal component and the second principal component obtained in this way are defined as the major axis and minor axis directions of an ellipse (hereinafter referred to as “set ellipse”) that defines an allowable error region, respectively. Then, the intersection of the major axis and the minor axis is determined from a value indicating the center of distribution in a large number of non-defective product data.

In this way, after obtaining the direction of the major axis / minor axis and the intersections thereof, the distribution of a large number of non-defective products is a normal distribution in which the values at the intersections are averaged with the direction of the major axis as the spreading direction. As a predetermined spread based on the standard deviation, the focal point of the ellipse and the distance from the focal point are determined, and the set ellipse is determined.
That is, as shown in FIG. 12, when the distribution of a large number of non-defective products is the direction of the major axis as the spreading direction and the value at the intersection of the major axis with the minor axis is the average μ, that is, the major axis that intersects at the intersection And normal distribution N (μ, σ ² ) with standard deviation σ (dispersion: σ ² ) when the intersection is the origin (when μ = 0) in the coordinate plane determined from the short axis (see normal distribution curve) ).

In the present embodiment, when determining the set ellipse, a range of μ ± 3σ is used as the predetermined spread (limit value) in the normal distribution. That is, the set ellipse has a spread of ± 3σ around the intersection in the direction of the major axis.
As described above, the length of the major axis of the set ellipse is determined by using the range of μ ± 3σ when the distribution of a large number of non-defective data is a normal distribution as the spread in the direction of the major axis. Then, the focal point of the ellipse is obtained on the basis of the length of the major axis and the variation in the minor axis direction of the distribution of many good product data. As a result, the set ellipse is determined (3σ ellipse).
Also, when determining the set ellipse, based on the distribution variation in a large number of non-defective data, a focal point that becomes a point on the long axis so that a large number of non-defective data is almost entirely included from the average value of the two signals. May be determined in advance, and the set ellipse may be determined by determining the distance from the focal point by using the μ ± 3σ spread in the normal distribution described above.
As described above, when setting the allowable error region, an ellipse having a spread of μ ± 3σ in the normal distribution in the major axis direction is used, so that the non-defective product data 42 is theoretically about 99.7% in the major axis direction. Will be included.
By determining the set ellipse as described above, an allowable error region on the coordinate plane is set.

Here, the relationship between the separation value and the extension of the ellipse when the set ellipse is determined with a distribution of a large number of non-defective products as a normal distribution in the direction of the major axis will be described.
As described above, the measurement value on the boundary line that is the set ellipse has the separation value = 1. Therefore, as shown in FIG. 12, the separation value = 1 on the boundary line of the allowable error region, which is an ellipse having a spread of μ ± 3σ (3σ ellipse) in the normal distribution described above.
On the other hand, it is similar to the 3σ ellipse that is the shape of the boundary of the allowable error region, and the spread is μ ± 6σ in the normal distribution similar to that used when determining the set ellipse with the intersection point as the origin. On an ellipse having a 6σ ellipse (separation value = 2). Similarly, the separation value = 3 on an ellipse (9σ ellipse) having a spread of μ ± 9σ in the normal distribution.
Therefore, in the coordinate plane shown in FIG. 12, the NG data is distributed at the position where the separation value is about 3.

By setting the allowable error area as described above, when evaluating the film formation quality of the inspection target component, the variation (measurement error) of the detection signal due to the influence of the temperature condition, the shape error, etc. of the inspection target component W Therefore, accurate determination (equal evaluation) according to the properties of the inspection target component W can be performed.
In addition, according to the present embodiment, since the film formation quality can be evaluated regardless of the relationship between the detection signal and the adhesion strength, it is not necessary to perform the adhesion strength measurement step, and the equipment cost and time cost for the evaluation are reduced. It becomes possible.

20 Inspection apparatus 30 Sensor Si Electromagnetic signal So Detection signal B Base material F Thermal spray coating W Inspection target part (preliminary inspection target part)

Claims (4)

A thermal spray coating quality evaluation method for evaluating the film formation quality of a component to be inspected whose surface is coated with a thermal spray coating,
The adhesion strength measurement step of measuring the adhesion strength of the thermal spray coating on the substrate in a plurality of preliminary inspection target parts coated with different coating conditions on the surface of the substrate, respectively,
Preliminary electromagnetic signals are applied to a plurality of preliminary inspection target parts coated with different coating conditions on the surface of the substrate by a thermal spray coating, and preliminary detection signals generated in the preliminary inspection target parts by the preliminary electromagnetic signals are generated. Detecting a preliminary detection step;
Create a calibration curve based on the relationship between the adhesion strength measured in the adhesion strength measurement step and the preliminary detection signal detected in the preliminary detection step in the preliminary inspection target part corresponding to the coating condition. Process,
A detection step of applying an electromagnetic signal to the inspection target component and detecting a detection signal generated in the inspection target component by the electromagnetic signal;
From the relationship between the calibration curve created in the calibration curve creation step and the detection signal detected in the detection step, the adhesion strength of the thermal spray coating to the substrate is calculated, and the film formation quality in the inspection target component is calculated. An evaluation process for evaluating ,
The substrate is formed of a non-magnetic material;
In the preliminary detection step, two types of the preliminary electromagnetic signals having different frequencies are applied to a surface of the preliminary inspection target part that is not coated with the thermal spray coating, and the preliminary electromagnetic signal according to each frequency is used to generate the preliminary electromagnetic signal. An output difference between two kinds of signals generated in the inspection target part is detected as the preliminary detection signal;
In the detection step, two types of electromagnetic signals having different frequencies are applied to the surface of the inspection target component that is not coated with a thermal spray coating, and the electromagnetic inspection signal generated by each frequency generates the inspection target component. Detecting the output difference between the two types of signals as the detection signal;
A method for evaluating the quality of a thermal spray coating. In the adhesion strength measurement step and the preliminary detection step, the adhesion strength of the thermal spray coating to the substrate in the preliminary inspection target part under a predetermined reference temperature condition and a comparative temperature condition different from the reference temperature condition is measured. Along with the preliminary detection signal,
In the calibration curve creation step, the reference temperature is determined based on the relationship between the adhesion strength measured in the adhesion strength measurement step and the preliminary detection signal detected in the preliminary detection step in the preliminary inspection target part corresponding to the coating condition. After creating a standard calibration curve under conditions and a comparative calibration curve under comparative temperature conditions, the temperature difference between the standard temperature condition and the comparative temperature condition and the positional relationship between the standard calibration curve and the comparative calibration curve Based on the temperature condition of the detection step, the calibration curve is created by performing a correction to translate the reference calibration curve,
The method for evaluating the quality of a thermal spray coating according to claim 1 , wherein: A thermal spray coating quality evaluation method for evaluating the film formation quality of a component to be inspected whose surface is coated with a thermal spray coating,
The adhesion strength measurement step of measuring the adhesion strength of the thermal spray coating on the substrate in a plurality of preliminary inspection target parts coated with different coating conditions on the surface of the substrate, respectively,
Of the surfaces of the plurality of preliminary inspection target parts coated with different coating conditions, the surface of the base material is coated on the both sides of the surface coated with the sprayed coating and the uncoated side. A first preliminary detection step of applying a first preliminary electromagnetic signal, and detecting an output difference between signals generated on each surface of the preliminary inspection target component by the first preliminary electromagnetic signal as a first preliminary detection signal;
From the relationship between the adhesion strength measured in the adhesion strength measurement step and the first preliminary detection signal detected in the first preliminary detection step in the preliminary inspection target part corresponding to the coating condition, a first calibration curve is obtained. Creating a first calibration curve; and
A first electromagnetic signal is applied to both surfaces of the surface to be inspected, the side coated with the thermal spray coating and the side not coated, and each of the components to be inspected by the first electromagnetic signal. A first detection step of detecting an output difference of signals generated on the surface as a first detection signal;
Two types of second preliminary electromagnetic signals having different frequencies are applied to the plurality of preliminary inspection target parts coated with different coating conditions on the surface of the substrate by a thermal spray coating, and the second preliminary electromagnetic signals corresponding to the respective frequencies are applied. A second preliminary detection step of detecting, as a second preliminary detection signal, an output difference between two types of signals generated in the preliminary inspection target part by an electromagnetic signal;
From the relationship between the adhesion strength measured in the adhesion strength measurement step and the second preliminary detection signal detected in the second preliminary detection step in the preliminary inspection target part corresponding to the coating condition, a second calibration curve is obtained. Creating a second calibration curve,
Two types of second electromagnetic signals having different frequencies are applied to the inspection target component, and an output difference between the two types of signals generated in the inspection target component by the second electromagnetic signals according to the respective frequencies is expressed as a second detection signal. Detecting as a second detection step;
When the base material is a non-magnetic material, the surface of the base material is coated with a thermal spray coating on the side not covered with the thermal spray coating among the surfaces of the plurality of parts to be inspected under different coating conditions. Applying two types of third preliminary electromagnetic signals having different frequencies, and using the third preliminary electromagnetic signal at each frequency as an output difference between the two types of signals generated in the preliminary inspection target component as a third preliminary detection signal Detecting a third preliminary detection step;
From the relationship between the adhesion strength measured in the adhesion strength measurement step and the third preliminary detection signal detected in the third preliminary detection step in the preliminary inspection target part corresponding to the coating condition, a third calibration curve is obtained. Creating a third calibration curve,
Two types of third electromagnetic signals having different frequencies are applied to the surface of the part to be inspected that is not coated with the thermal spray coating, and generated in the part to be inspected by the third electromagnetic signal according to each frequency 2 A third detection step of detecting the output difference of the types of signals as a third detection signal;
Of the relationship between the first calibration curve and the first detection signal, the relationship between the second calibration curve and the second detection signal, and the relationship between the third calibration curve and the third detection signal, From at least two relationships, calculating the adhesion strength of the thermal spray coating to the base material, and evaluating the film formation quality in the inspection target part, comprising an evaluation step,
A method for evaluating the quality of a thermal spray coating. A thermal spray coating quality evaluation method for evaluating the film formation quality of a component to be inspected whose surface is coated with a thermal spray coating,
A first electromagnetic signal is applied to both of the surfaces of the plurality of parts to be inspected having different coating conditions for the thermal spray coating on both the side coated with the thermal spray coating and the side not coated. A first detection step of detecting, as a first detection signal, an output difference between signals generated on each surface of the inspection target component by one electromagnetic signal;
Two types of second electromagnetic signals having different frequencies are applied to a plurality of parts to be inspected having different coating conditions of the thermal spray coating, and two types of signals generated in the parts to be inspected by the second electromagnetic signals having different frequencies. A second detection step of detecting the output difference of the signal as a second detection signal;
When the base material is a non-magnetic material, two types of third electromagnetics having different frequencies are provided on the surface of the plurality of parts to be inspected having different coating conditions of the thermal spray coating on the side not coated with the thermal spray coating. A third detection step of applying a signal and detecting, as a third detection signal, an output difference between the two types of signals generated in the inspection target component by the third electromagnetic signal at each frequency;
A first coordinate axis indicating one of the two signals of the first detection signal, the second detection signal, and the third detection signal, and the other of the two signals orthogonal to the first coordinate axis A coordinate plane defined by the second coordinate axis, and based on the distribution of points on the coordinate plane determined from the values of the two signals, a tolerance region in the coordinate plane is set in advance, and the two An evaluation step of evaluating film formation quality in the inspection target component depending on whether or not a point on the coordinate plane determined from a signal value is within the allowable error region,
A method for evaluating the quality of a thermal spray coating.

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