JPH01162132A - Adhesion tester for film - Google Patents

Abstract

PURPOSE:To detect a critical load accurately with one measurement, by providing a vertically relaxing device on a sample stage with the vertical movement of a load sensor and a measuring tool together to eliminate the need for using several kinds of weight. CONSTITUTION:A moving object 2 is allowed to be displayed vertically with a driving source 24. A load sensor 4 is allowed to detect a load in two ways, vertically and horizontally. A sample stage 6 is provided as opposed to a measuring tool 5 and made movable horizontally in a horizontal plane. A vertically relaxing device 8 relaxes a force applied vertically to the stage 6. A signal processing section makes the tool 5 abut a sample 7 placed on the stage 6 to process vertical and horizontal detection signals of the sensor 4 as obtained when the moving object 2 is displaced gradually. This eliminates the need for using several kinds of weight thereby enabling accurate detection of a critical load in one measurement.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an adhesion testing device that is applied to testing the adhesion of hard coatings including ceramic coatings.

[Conventional technology]

The adhesion of hard coatings of metals and ceramic materials formed by CVD, PVD, etc. and soft coatings of polymeric materials such as paints can be tested by a scratch destruction method. That is, when a vertical load is gradually applied to the coating surface using a scratch tool such as a diamond cone, and at the same time the coating surface is continuously moved in the horizontal direction, the coating surface peels off at the corresponding locations. The load at which this peeling occurs is detected as a critical load indicating the degree of adhesion. for example,
JP-A-57-86741 discloses scratch strength.

An apparatus for measuring scratch resistance is shown.

This measuring device has a scratching needle attached to one end of the horizontal arm and a strain gauge type transducer to the other end of the horizontal arm. A predetermined load is applied using a weight, and the moving table on which the test piece is placed is moved in a predetermined direction at a constant speed. The scratch strength of the specimen is determined from the transducer output signal generated during this movement.

Scratch resistance is measured. Furthermore, various loads are applied by replacing weights.

The conventional adhesion test equipment described above requires
Load is applied discontinuously using weights. Therefore, as mentioned above, when detecting critical loads, it is necessary to repeat measurements using weights of various weights. In particular, in order to increase the resolution of critical loads, a large number of weights must be used. However, there was the trouble of having to repeat the measurements many times. In addition, in conventional adhesion test equipment, the pressurizing part that gradually applies a load to the coating surface and the sensor are completely independent, which leads to an increase in the size of the equipment and makes it complicated to handle. There was a drawback.

Therefore, as described in Japanese Patent Application No. 62-60765, the applicant of the present application developed a coating that has a compact structure, is easy to handle, and can detect critical loads with high resolution. We are proposing an adhesion testing device.

In this adhesion test device, the load is applied in the vertical direction (Z-axis direction).
Since the load applying unit that applies the load to the load and the load sensor that detects the load in the Z-axis direction are coaxially provided, the shape of the device becomes compact.

[Problem that the invention seeks to solve]

To test adhesion, the previously proposed device only detected changes in load in the Z-axis direction.

When the coating is as thick as 20 to 30 microns,
The load at which fracture occurs (critical load) can be measured by changing the load in the Z-axis direction.

However, when the thickness of the coating is as thin as several microns, it is difficult to detect changes in critical load from changes in load in the Z-axis direction.

An object of the present invention is to provide an adhesion testing device with high sensitivity and good response by detecting changes in load not only in the Z-axis direction but also in the X-axis direction.

[Means for solving problems]

The present invention includes a moving body 2 that can be vertically displaced by a drive source 24 such as a motor, and a load sensor 4 that is attached to the moving body 2 and is capable of detecting loads in two directions, vertical and horizontal. , a measurement tool 5 provided on the load sensor 4 , a sample stage 6 provided opposite to the measurement tool 5 and movable at least horizontally in a horizontal plane, and a sample stage 6 perpendicular to the sample stage 6 A vertical relaxation device 8 for relieving the force applied in the direction, and a load when the measuring tool 5 is brought into contact with the sample 7 placed on the sample stage 6 and the movable body 2 is gradually displaced. A signal processing unit 33 that processes the vertical and horizontal detection signals of the sensor 4
, 34.49 are provided.

[Effect]

The load sensor 4 and the measurement tool 5 are displaced together by the drive source 35, and a load is applied to the sample 7. Since the load applying section and the load detection section are arranged coaxially, the device can be made compact and easy to handle. Also, the vertical relaxation device 8 is connected to the sample stage 6.
Since this is provided, a load can be applied continuously when the movable body 2 is displaced. Therefore, it is not necessary to use many types of weights, and the critical load can be accurately detected by one measurement. In addition, the load sensor 4 is capable of detecting load changes not only in the vertical direction but also in the horizontal direction, so even when the coating on the sample 7 is thin, it has high sensitivity and quick response, ensuring that the coating is destroyed. can be detected.

C Embodiment] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIGS. 1 and 2 show the structure of the mechanism of this embodiment. In FIG. 1, 1 indicates a case;
Inside this case 1, there is a Z (vertical direction) drive motor and an
A drive motor is provided. These Z drive motors and X drive motors are pulse motors, and the ZR drive motor feed pitch is extremely fine. The arm 2 is moved up and down by two drive motors. Arm 2
protrudes from the opening 3 of the case 1 in the horizontal direction.

At the tip of this arm 2, as shown in FIG.
As will be described later, a load sensor 4 is attached that can detect changes in load in both the X-axis direction and the X-axis direction.

A diamond cone 5 as a scratching tool is provided to the operating portion of the load sensor 4. Therefore, the load sensor 4 and the diamond cone 5 move up and down together with the arm 2. Below the diamond cone 5,
A sample stage 6 facing the diamond cone 5 is provided, and a sample 7 is fixed on the sample stage 6. Sample 7
For example, a metal base is coated with ceramics. The load sensor 4 is replaceable depending on the hardness of the coating of the sample 7.

The sample stage 6 is supported on an XY stage 9 via a vertical relaxation device 8. This XY stage 9 is automatically moved at a constant speed by a predetermined iF (for example, 5 to 20 (mm)) in the longitudinal direction (X-axis direction) of the sample 7 by an X drive motor. On the other hand, the width direction (Y-axis direction) of the sample 7 is manually moved using the adjustment screw 10. Further, the pushbutton switch 11 can cause an arbitrary amount of displacement in the X-axis direction and in the X-axis direction. The vertical relaxation device 8 includes a cylindrical housing 12, a slider 13 that is slidably fitted into the housing 12 and has a sample stage 6 fixed to its upper part, and applies an upward biasing force to the slider 13. It is composed of a spring 14 for applying and a ring 15 for locking. This locking ring 15 is removable and allows the spring 14 to be replaced. This vertical relaxation device R8 is an example, and the slider 13 may not be provided and damper means other than the spring may be used.

The vertical relaxation device 8 allows a load that changes analogously to be applied to the sample 7 via the diamond cone 5. Unlike this invention, assuming that the sample stage 6 is placed on an extremely hard table, a large load (in steps) is generated at the moment when the diamond cone 5 contacts the sample 7 by the Z drive motor, causing breakage. When this occurs, a problem arises in that the critical load cannot be detected accurately. In order to avoid this problem, it is conceivable to displace the diamond cone 5 downward at an extremely low speed, but this would complicate the configuration and lengthen the measurement time. In this invention, since the vertical relaxation device 8 is provided, when the diamond cone 5 is gradually moved downward by the Z drive motor, a continuously increasing load can be generated.

FIG. 3 shows an example of the load sensor 4. In FIG. 3, 21 indicates a shaft that receives a load Fz in the X-axis direction and a load Fx in the X-axis direction. The shaft 21 is supported by a primary diaphragm 22 and a secondary diaphragm 23, and the tip of the shaft 21 is connected to a Z-axis beam 24 having both ends fixed.
is fixed. These primary diaphragm 22 and secondary diaphragm 23 are disk-shaped. The Z-axis beam 24 is supported by a secondary diaphragm 23 and
A Z-axis sensor 25 is attached to the center of the axial beam 24. Further, a Z-axis stopper 26 is provided opposite the tip of the shaft 21, and the amount of displacement of the shaft 21 in the X-axis direction is regulated. The peripheral portions of the primary diaphragm 22 and the secondary diaphragm 23 are fixed to the mount portion 27 . 28
is the case.

A cylindrical X-axis beam 29 is arranged above the mount section 27, and an X-axis sensor 30 is attached to this X-axis beam 29. Output signals from the two-axis sensor 25 and the X-axis sensor 30 are taken out to the outside via an amplifier and a cord provided on the circuit board.

As mentioned above, the shaft 21 is supported by the primary diaphragm 22 and the secondary diaphragm 23 that are provided in parallel, so it has a degree of freedom in the X-axis direction, but has high rigidity in the X-axis direction. have

Therefore, the load Fx in the X-axis direction is
and is transmitted to the mount part 27 through the secondary diaphragm 23, the X-axis beam 29 is decentered in the X-axis direction by the mount part 27, and the X-axis sensor 30 glued in the X-axis direction generates a detection signal proportional to the load Fx. can get. Here, since the rigidity of the X-axis beam 29 in the Z-axis direction is very large, the output signal of the X-axis sensor 30 is not affected by the load F2.

Further, the load Fz in the Z-axis direction is directly transmitted to the biaxial beam 24 by the shaft 21, and a detection signal proportional to the load Fz is obtained by the Z-axis sensor 25 bonded to the surface of the Z-axis beam 24. In this case, the load Fx does not displace the Z-axis beam 24 in the axial direction due to the characteristics of the primary diaphragm 22 and the secondary diaphragm 23, so the influence of the load Fx does not affect the detection signal of the load Fz.

The two-axis sensor 25 and the X-axis sensor 30 of this load sensor 4
is a small semiconductor sensor that utilizes the piezoresistive effect. The load sensor 4 is smaller, has higher sensitivity, and has wider frequency characteristics than a strain gauge. Therefore, it is possible to accurately detect instantaneous and minute fluctuations in load caused by hard destruction of a thin film surface formed by CVD, PVD, or the like.

In addition, as the load sensor 4, an AE (acoustic
Emissilon) sensors can also be used, but
The effectiveness of the sensor is limited if the AE of the coating surface that occurs at critical loads is equal to the frequency response of the AE sensor. That is, since the frequency of AE on the coating surface under critical load varies depending on the material, adhesion, etc., there is a problem in that AE sensors with various frequency characteristics are required. Wide band A
It is possible to use an E sensor, but this type of A
E-sensors are expensive, large, and typically have low sensitivity and poor S/N.

FIG. 4 shows the overall system configuration of this embodiment,
Reference numeral 31 shown surrounded by a broken line is a mechanism section, 32 is a drive section, 33 and 34 are measurement signal processing sections, and 49 is a computer.

As described above, the mechanism section 31 includes a load sensor 4 and a diamond cone 5 that are moved up and down by two drive motors 35.
, a sample stage 6 on which the sample 7 is placed, a vertical relaxation device 8, and an XY stage 9, and an X drive motor 36 is provided in association with the XY stage 9. The drive unit 32 is provided with an X drive driver 37 that generates a drive signal for the Z drive motor 35 and an X drive driver 38 that generates a drive signal for the X drive motor 36.

A detection signal in the Z-axis direction from the two-axis sensor 25 of the load sensor 4 is supplied to the auto-zero circuit 42 via the sensor amplifier 41 of the measurement signal processing section 33.

This auto-zero circuit 42 is a circuit that cancels the drift of the load sensor 4 and performs electrical zero adjustment. The output signal of the auto-zero circuit 42 is sent to the output terminal 4 as a recording signal.
3 and is also supplied to the absolute value circuit 44. For example, an XY recorder is connected to the output terminal 43. The absolute value circuit 44 converts the detection signal of the load sensor 4 in the Z-axis direction into a positive electrical signal. The output signal of this absolute value circuit 44 is output to the peak hold circuit 45. The signal is supplied to a peak detection circuit 46 and a touch detection circuit 47, respectively.

The peak hold circuit 45 detects and holds the peak value of the output signal of the absolute value circuit 44. The output signal of this peak hold circuit 45 is converted into a digital signal by an A/D converter 48 and supplied to a computer 49. The output signal of the peak detection circuit 46 and the output signal of the touch detection circuit 47 are also supplied to the computer 49 . The computer 49 is, for example, a 16-bit personal computer, which controls the sequence of measurements and displays measurement data such as critical load on a CRT display (not shown). Digital data from the A/D converter 48 is taken into the computer 49 as measurement data. From the output signal of the touch detection circuit 47, it is detected that the tip of the diamond cone 5 has contacted the sample 7, and from the output signal of the peak detection circuit 46, scratch breakage of the sample 7 in two axial directions is detected.

A detection signal in the X-axis direction from the X-axis sensor 3o of the load sensor 4 is supplied to the measurement signal processing section 34.

The measurement signal processing section 34 has the same configuration as the measurement signal processing section 33 described above. That is, the detection signal in the X-axis direction is taken out to the output terminal 53 via the sensor amplifier 51 and the auto-zero circuit 52, and is also supplied to the absolute value circuit 54. The output signal of this absolute value circuit 54 is supplied to a peak hold circuit 55 and a peak detection circuit 56. The output signal of the peak hold circuit 55 converted into a digital signal by the A/D converter 58 and the peak detection circuit 56
The output signal of is supplied to the computer 49.

Scratch breakage of the sample 7 in the X-axis direction is detected from the output signal of the peak detection circuit 56.

In addition to the scratch test in which the sample 7 is moved while changing the load continuously, various tests such as a hardness test in which the sample 7 is fixed or a test for the distribution of adhesion strength of the hard coating are carried out by the program of the computer 49. It is considered possible.

An example of the measurement results obtained from the recording signals from the output terminals 43 and 53 of the measurement signal processing units 33 and 34 mentioned above is shown in FIG. 5. The results are shown when sample 7 was moved in the X-axis direction at a predetermined speed. In Fig. 5, 51z indicates the load change in the X-axis direction, and 51X indicates the load change in the X-axis direction.When the hard coating of sample 7 is destroyed, the load drops instantaneously, as shown at 52. do. This instantaneous drop in load is detected by the peak detection circuit 56, and the peak hold circuit 4
The critical load is determined from the output signal of 5.

〔Effect of the invention〕

In this invention, the load sensor and the measurement tool are moved up and down together, and the sample stage is provided with a vertical relaxation device. Therefore, unlike conventional configurations, there is no need to use multiple types of weights, a continuously changing load can be applied to the sample, and the critical load can be accurately detected in a single measurement. It also enables program control of the measurement sequence. Furthermore, since the pressure section for applying a load to the sample and the sensor are integrated, the device can be made smaller and easier to handle.

In addition, since this invention detects load changes not only in the X-axis direction but also in the X-axis direction, the detection sensitivity can be increased, the response can be made faster, and even if the coating is thin, the coating will not be destroyed. Critical loads can be detected reliably. Furthermore, when measuring the critical load from the load change in the X-axis direction, it was necessary to supply the output signal of the sensor to a differentiating circuit to emphasize the change. However, it is troublesome to set the constants of the differential circuit depending on the thickness of the coating of the sample. According to this invention, a differentiation circuit can be made unnecessary.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the external appearance of a mechanism section in an embodiment of the present invention, FIG. 2 is a more detailed perspective view of the mechanism section in this embodiment, and FIG. 3 is a sectional view of an example of a load sensor. FIG. 4 is a block diagram of the entire system of this embodiment, and FIG.
The figure is a graph showing an example of measurement data obtained by this example. Explanation of main symbols in the drawings 2: Arm, 4: Load sensor, 5: Diamond cone, 7: Sample, 6: Sample stage, 8: Vertical relaxation device, 9: XY stage. Agent Patent Attorney Masato Sugiura Figure 5 Figure 2

Claims (1)

[Claims] A moving body capable of vertical displacement by a drive source such as a motor, a load sensor attached to the moving body and capable of detecting loads in two directions, the vertical direction and the horizontal direction, and the load sensor a measurement tool provided, a sample stage provided opposite the measurement tool and movable at least in the horizontal direction in a horizontal plane, and a force applied in a vertical direction to the sample stage. and the vertical direction and the horizontal direction of the load sensor when the measuring tool is brought into contact with the sample placed on the sample stage and the movable body is gradually displaced. 1. A coating adhesion testing device comprising: a signal processing section that processes each detection signal.