JPH02152152A - Material testing machine with scanning electron microscope - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Industrial Field of Application The present invention relates to a material testing machine equipped with a scanning electron microscope, and particularly to a material testing machine equipped with a scanning electron microscope, and in particular, it is capable of testing specimens by synchronizing repeated loads and aligning the load axis with the horizontal or vertical axis of the display screen. This is an image of the state of

B. Conventional technology For example, a test piece is captured by a scanning electron microscope while performing a fatigue test using a servo actuator, and a display device (for example, a CRT) is scanned synchronously with the scanning electron microscope.
A fatigue testing machine with a scanning electron microscope that displays an enlarged image is known. Generally, the image of the test piece is displayed by aligning the load axis with the horizontal axis of the display screen, but in this type of equipment, the test piece is placed within the field of view of the scanning electron microscope due to the repeated loads acting on the test piece. vibrates, and the image on a display device such as a CRT vibrates in the horizontal axis direction on both sides, which is the load axis direction.

Therefore, attempts have been made to apply a load pattern corresponding to the repeated load applied to the test piece to the deflection coil of a scanning electron microscope to prevent vibrations in the displayed image.

Problems to be solved by the C0 invention On the other hand, depending on the matching between the scanning electron microscope and the material testing machine, it is necessary to adjust the focal length of the objective lens of the scanning electron microscope. When the collision position of the electron beam changes and the horizontal axis of the CRT display screen and the load axis of the test piece do not necessarily match, and the above-mentioned load pattern is not applied to the deflection coil, as shown in Fig. 5 (a).
The image vibrates like an arrow with a predetermined inclination to the horizontal axis of the screen. As mentioned above, when a signal corresponding to the load pattern is applied to the deflection coil, the vibration in the horizontal direction (load axis direction) stops, but the vibration in the vertical direction does not stop, and the image is shown by the arrow in Figure 5 (b). It vibrates like.

Therefore, conventionally, vertical image vibration has been prevented by rotating the deflection coil itself by a predetermined angle, but the adjustment work is complicated, and electrical compensation is desired.

The technical problem of the present invention is to prevent vertical or horizontal vibration of an image on a display screen without mechanically rotating a deflection coil.

Means for Solving Problem D6 The present invention includes an actuator that loads a test piece, a servo device that controls the actuator to load the test piece in a predetermined load pattern, and a
A scanning electron microscope that obtains a detection output by two-dimensionally scanning the axis and the Y-axis perpendicular to this, and a scanning electron microscope that scans the detection output in synchronization with the scanning of this scanning electron microscope and displays a load axis on the horizontal or vertical axis of the screen. The present invention is applied to a material testing machine equipped with a scanning electron microscope, which is equipped with a display device that displays an enlarged image by aligning the images.

The above technical problem is solved by the following configuration.

A θ setting means for setting an arbitrary angle θ with respect to the horizontal or vertical axis of the display screen, a cosine calculation means for calculating the cosine cos O of the angle θ, a sine calculation means for calculating the sine sin θ of 0, and repetition according to the load pattern. Load amplitude Δa
amplitude signal output means for outputting an amplitude signal representing Δa;
and cos θ, and Δa and s
and a second multiplication means for calculating a product with inθ.

The electron beam is then deflected in the X-axis direction by the product of Δa and cos O, and scanned while being deflected in the Y-axis direction by the product of Δa and sin θ.

E1 effect When the electron beam is not deflected as in the present invention, as the impact position of the electron beam on the test piece changes due to repeated loading and adjustment of the focal length, a change occurs on the display screen as shown in FIG. 5(a). The image vibrates at a certain angle θ with respect to the horizontal direction on both sides. Therefore, in the present invention, the component in the horizontal axis direction of the vibrating image is made to disappear by deflecting the electron beam in the X-axis direction by the product of Δa and cos θ. In addition, the component in the vertical axis direction is the product of Δa and sinθ, which moves the electron beam to Y
Deflect it in the axial direction and make it disappear. Therefore, by performing two-dimensional scanning of the electron beam and deflection in the X and Y axis directions described above, an enlarged image of the test piece is projected on both display surfaces with the scanning center stationary at the origin of one surface.

F. Example One embodiment will be described with reference to FIGS. 1 to 4.

In FIG. 1 showing the overall configuration, 10 is a scanning electron microscope, which has an electron gun 11, a scanning deflection coil 12, a synchronous observation deflection coil 15, a detection section 13°, a specimen chamber 14, and a sample chamber 14. A test piece TP gripped by grippers 21 and 22 is inserted into.

The enlarged image of the test piece TP captured by the scanning electron microscope 10 is visualized on a display device, for example, a CRT 51. That is, the scanning of the scanning deflection coil 12 and the CRT 51 is synchronized by the synchronous scanning circuit 52.
2, the electron beam is used to move the specimen TP over the X and Y axes (Fig. 2).
The change in the intensity of secondary electrons or reflected electrons emitted from the surface of the test piece TP and detected by the detection unit 13 is detected by C in synchronization with the electron beam of the scanning electron microscope 1o.
The image is scanned on the RT 51 and an enlarged image is displayed.

As shown in FIG. 2, the synchronous observation deflection coil 15 includes X-axis lateral coils 15
Y1, 15Y2, and X-axis side coils 15X□, 1
5X2 deflects the electron beam in the X-axis direction, which is the load axis direction,
The Y-axis direction deflection coils 15Y and 15Y2 deflect the electron beam in the Y-axis direction perpendicular to the direction of the load axis. The control will be described later.

One gripper 21 of the fatigue testing machine is fixed, the other gripper 22 is connected to a load rod 23. It is connected to a servo actuator 25 via a load cell 24, and a test piece TP is loaded via this gripper 22. Servo actuator 2
5 is supplied with pressure oil from a hydraulic source 27.

The operating panel 31 is an operating section for inputting a load average value Mean and a load amplitude Δa' as shown in FIG. 3 in order to set a load pattern for applying repeated loads.

It has a scanning speed selection section that selects between slow scan and rapid scan, and an input section that inputs a manual deflection signal that manually controls the synchronous observation deflection coil 15, and signals from each section are input to the controller 32. . controller 3
2 is an oscillation circuit 33 that transmits signals representing the weight average value and load amplitude.
The oscillation circuit 33 supplies the summing point 34 with a control setting signal corresponding to the load pattern of the repetitive load. This addition point 34 is connected to the load cell 24 to the load amplifier 2.
A load feedback signal is also supplied via 6, and a deviation signal of both human force signals is supplied via an amplifier 35 to a servo actuator 25, which loads the test specimen TP with a set load pattern.

The synchronous observation circuit 60 allows the images to be aligned with the horizontal axis of the CRT screen on both sides of the CRT 51 as shown in FIG. This prevents the test piece from vibrating at an angle O with respect to the direction, and projects the scanning center of the test piece stationary at the origin ○ on the CRT screen. The synchronous observation circuit 60 receives an average value signal and a manual setting signal from the controller 32, and also receives a detected load signal from the load amplifier 26.

Details of such a synchronous observation circuit 60 are shown in FIG.

The θ setting device 61 sets the angle O that the vibration direction of the enlarged image that vibrates due to repeated loads makes with the X axis, and stores the angle θ that is predetermined according to the focal length of the objective lens to be adjusted. . The subtracter 62 subtracts the average value signal, which is the output of the controller 32, from the repetitive load detection signal, which is the output of the load amplifier 26, to form a signal Δa' containing only the vibration component from the repetitive load component. Gain setting device 6
3 is this Δa' multiplied by a predetermined gain g, Δa (=
Δa'Xg) is calculated. Here, this gain is determined according to the rigidity of the test piece, etc., and is determined so that the amount of strain can be displayed on the display screen. On the other hand, the cosine function generator 64 and the sine function generator 65 calculate the cosine cos θ and sine sin θ of the angle signal θ output from the setting device 61. Multipliers 66 and 67 add Δ to cosO and 5jnO.
By multiplying each by a, Δa-cosO and Δa-sin θ are calculated. For the switches 68 and 69, the a contact is closed in the case of automatic setting, and the b contact is closed in the case of manual setting. In the case of automatic setting, Δa-cosO is the X-axis deflection coil 15X.

15X2 and Δa-sin θ are input to the Y-axis deflection coils 15Y and 15Y2, respectively. In the case of manual setting, the X-axis deflection signal is input from the operation panel 31.

A Y-axis deflection signal is input to each coil 15X□ to 15Y2.

That is, this synchronized wt festival circuit 60 always deflects the electron beam by Δa'cosθ in the X-axis direction for an image vibrating at an angle O9 amplitude Δa with respect to the X-axis as shown in FIG. The electron beam is always deflected by Δa·sin O in the axial direction.

On the other hand, the controller 32 supplies a scanning speed setting signal to the synchronous scanning circuit 52, and controls the scanning electron microscope 10 and the CRT.
51, the scanning speed of the electron beam is set. For example, the scanning speed is set in the range of 1/60 seconds to several hundred seconds for each side, and
When displaying a normal image on a CRT 51, it is set to 1/60 seconds, and when shooting an image displayed on a CRT 51 with a camera, the setting is set to 1/60 seconds, which is sufficient for sufficient exposure depending on the brightness of the image, for example, 100 seconds. Set to seconds.

Next, the operation of the control device configured as described above will be explained.

It is assumed that the automatic setting is selected and the switches 68 and 69 are switched to a contact.

It is assumed that a repeated fatigue test is performed using the servo actuator 25 in a load pattern with a load average value Mean and a load amplitude Δa' shown in FIG. Therefore, the controller 32 sends a signal representing the weight average value Mean and a signal representing the load amplitude Δa' to the oscillation circuit 33, and the oscillation circuit 33 supplies the waveform signal shown in FIG. 3 to the summing point 34. At this time, the controller 32 instructs the synchronous scanning circuit 52 to perform rapid scanning using the scanning speed setting signal, and the synchronous scanning circuit 52 controls the scanning electron microscope 10 and the CRT 51 so that one screen is scanned at 1/60 second. .

The load acting on the test piece is detected by the load cell 24, amplified by the load amplifier 26, and fed back to the summing point 34. At this addition point 34, a deviation between the waveform signal of the load pattern and the load signal is calculated, and a signal corresponding to the deviation is input to the servo actuator 25 via the amplifier 35. As a result, the servo actuator 25 is driven, and a load is repeatedly applied to the test piece.

At this time, the detection signal of the load amplifier 26 is input to the subtracter 62 of the synchronous observation circuit 60, where the average value Mean is subtracted from the detection signal to calculate a signal Δa' representing the amplitude. Then, the gain setter 63 calculates Δa, and the multipliers 66 and 67 output Δa′cosθ and Δa−si
nθ is calculated, and the X-axis direction coil 15X,
15X2 and Y-axis side coils 15Yi and 15Y2. As a result, the electron beam is always deflected in the x and y axis directions so as to collide with the origin 0 of the observation area of the test piece shown in FIG. This electron beam is also deflected by the scanning deflection coil 12 so as to two-dimensionally scan the specimen, so that C
The still enlarged image of the WA observation area is displayed on the RT screen.

The case where the load axis coincides with the horizontal direction of the display screen has been described above, but depending on the case, the load axis may also coincide with the vertical direction. Further, although the amplitude was obtained by subtracting the input average value from the actual load, the amplitude may be obtained by calculation from the actual load, or the amplitude input from the operation unit may be directly used.

G1 Effects of the Invention Since the present invention is configured as described above, the enlarged image of the test specimen on the display screen can be kept stationary without vibration in any direction by electrical control without mechanically rotating the deflection coil. Images can be formed.

[Brief explanation of the drawing]

Figures 1 to 4 show one embodiment of the present invention.
The figure is a block diagram showing the overall configuration, and Figure 2 is synchronization 1.
FIG. 3 is a graph illustrating a load pattern, and FIG. 4 is a block diagram showing details of a synchronous observation circuit. FIG. 5 is a diagram explaining the conventional problems. 10: Scanning electron microscope 12: Scanning deflection coil 13: Detection section 14: Sample chamber 15. 15X1, 15X2: X-axis direction coil 15Y,
15Y2: Y-axis direction coil 21. 22: Grip tool 24: Load cell 25: Servo actuator 26: Load amplifier 31: Operation panel 32: Controller 1-Roller 33: Oscillation circuit 51: CRT
52: Synchronous scanning circuit 60: Synchronous observation circuit
61: θ setter 62: Subtractor 63 Gain setter 64: Cosine function generator 65: Sine function generator 6
6.67: Multiplier patent applicant: Shimadzu Corporation Patent attorney Fuyuki Nagai Figure 2 Figure 5 Figure 3 Figure 4

Claims (1)

[Claims] an actuator that loads a test piece; a servo device that controls the actuator to load the test piece in a predetermined load pattern; A scanning electron microscope that scans to obtain a detection output, and displays an enlarged image by scanning the detection output in synchronization with the electron beam scanning of the scanning electron microscope and aligning the load axis with the horizontal or vertical axis of the screen. A material testing machine with a scanning electron microscope, comprising: a display device configured to perform a scanning electron microscope; a calculation means, and the θ
sine means for calculating the sine sin θ of the load pattern, amplitude signal output means for outputting an amplitude signal representing the amplitude Δa of the repetitive load due to the load pattern, first multiplication means for calculating the product of the Δa and cos θ, and the Δa and a second multiplication means for calculating the product of Δa and cos θ.
A materials testing machine with a scanning electron microscope, characterized in that scanning is performed by deflecting the electron beam in the X-axis direction by the product of θ, and deflecting the electron beam in the Y-axis direction by the product of Δa and sin θ. .