KR101161775B1 - Device and method for measurement of hardness and tensile properties - Google Patents

Abstract

The present invention relates to an apparatus and method for measuring hardness and tensile properties.
The hardness and tensile properties measuring device for measuring the hardness of the specimen according to an embodiment of the present invention, the image unit for imaging the image of the indenter and the specimen, the indenter and the image of the specimen by moving the indenter to press-fit the specimen It may include a drive unit, a sensor unit for measuring the indentation displacement and indentation load according to the indentation of the indenter, a calculation unit for calculating the tensile characteristic value or hardness value using at least one of the image, the indentation displacement and the indentation load of the specimen.

Description

DEVICE AND METHOD FOR MEASUREMENT OF HARDNESS AND TENSILE PROPERTIES}

The present invention relates to an apparatus and method capable of simultaneously measuring hardness and tensile properties.

Power plant equipment is exposed to aging due to high temperatures, high pressures, or long periods of operation. Power plants generate large amounts of power, so if power plant equipment fails, it can lead to power outages and have a major impact on power providers and power consumers. Can be. Therefore, the health assessment of the facilities of the power plant is very important.

In order to assess the integrity of power plant installations, the mechanical properties of strength, ductility, toughness, hardness, etc., against the static and dynamic loads of the materials making up the installations can be evaluated.

Conventionally, to measure the hardness, the contactor was visually positioned on the specimen in the field. Therefore, it can be used only at the place where the movement of the indenter can be visually checked.

The present invention relates to an apparatus and method capable of measuring hardness and tensile properties capable of controlling the position of the indenter through an image obtained from a camera lens.

It is an object of the present invention to provide an apparatus and method capable of simultaneously measuring hardness and tensile properties.

According to one aspect of the invention, there is provided an apparatus for measuring hardness and tensile properties.

In the hardness and tensile properties measuring device for measuring the hardness of the specimen according to an embodiment of the present invention, the indenter and the image portion for imaging the specimen, the indenter is moved by using the obtained indenter and the image of the specimen A driving unit for indenting the specimen, a sensor unit for measuring the indentation displacement and the indentation load according to the indentation of the indenter, and a calculation unit for calculating the tensile characteristic value or the hardness value using at least one of the image, the indentation displacement, and the indentation load of the specimen. Can be.

According to another aspect of the present invention, a method for measuring hardness and tensile properties is provided.

Method for measuring the hardness of the specimen using the hardness and tensile properties measuring apparatus according to an embodiment of the present invention is to obtain an image of the specimen and the indenter, fixing the indenter to the indentation position of the specimen, the indenter Indenting, removing the indentation applied to the specimen through the indenter, measuring the indentation displacement and indentation load according to the indentation, acquiring an image of the specimen after indentation, and generating image information through the acquired image The method may include calculating tensile property values and hardness values of the specimen using the image information, the indentation displacement, and the indentation load.

Apparatus and method for measuring hardness and tensile properties according to an embodiment of the present invention have an effect of accurately controlling the position of the indenter through an image obtained from a camera lens.

Apparatus and method for measuring hardness and tensile properties according to an embodiment of the present invention has an effect that the constraint on the measurement location can be reduced because the position of the indenter is controlled through an image obtained from a camera lens.

Apparatus and method for measuring hardness and tensile properties according to an embodiment of the present invention have the effect of simultaneously measuring the hardness and tensile properties of a specimen.

1 is an exemplary view showing a hardness and tensile properties measuring apparatus according to an embodiment of the present invention.
2 is an exemplary view showing a position where the camera lens of the hardness and tensile properties measuring device is incorporated.
Figure 3 is an exemplary view showing a method for controlling the position of the indenter according to an embodiment of the present invention.
4 is an exemplary view illustrating a method of measuring a diagonal length of an indentation mark according to an exemplary embodiment of the present invention.
5 is a flowchart illustrating a method of measuring hardness and tensile properties according to an embodiment of the present invention.
6 is an exemplary view showing a hardness measurement screen according to an embodiment of the present invention.

The present invention may be variously modified and have various embodiments, and specific embodiments will be illustrated in the drawings and described in detail with reference to the accompanying drawings. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to the hardness and tensile properties measuring apparatus and the hardness and tensile properties measuring method according to an embodiment of the present invention.

1 is an exemplary view showing a hardness and tensile properties measuring apparatus according to an embodiment of the present invention.

Referring to FIG. 1, the hardness and tensile property measuring apparatus 100 includes an input unit 110, a controller 120, a driver 130, a sensor unit 140, an image unit 150, a calculator 160, and an output unit. It may include a portion 170.

The input unit 110 receives an indenter command for controlling the indenter 180 for injecting the specimen. The input unit 110 may determine the initial position of the indenter 180. That is, the input unit 110 may input a control signal so that the indenter 180 is located on the specimen to which the indentation is applied.

The input unit 110 may input any signal controlling the hardness and tensile property measuring device as well as the indenter command. For example, the input unit 110 may receive a signal for acquiring an image from a camera lens built in the hardness and tensile characteristic measuring device. The input unit 110 transmits the received indenter command or the image acquisition signal to the controller 120.

The controller 120 receives the indenter command and generates a drive signal according to the indenter command. The controller 120 generates a driving signal for driving the driver 130 that controls the movement of the indenter 180 according to the indenter command. The controller 120 transmits the generated driving signal to the driver 130.

The controller 120 may control the image unit 150 to acquire an image of the specimen or the indenter 180 according to the signal input to the input unit 110. For example, when the controller 120 receives an image acquisition signal from the input unit 110, the controller 120 may generate an image unit driving signal that can be controlled to drive the image unit 150 to acquire an image.

 The driver 130 controls the movement of the indenter 180. The driver 130 receives a drive signal from the controller 120. For example, the driving unit 130 may move the indenter 180 according to the received driving signal to position the indenter 180 to a place where the indentation is applied to the specimen.

In addition, the driving unit 130 may control the indenter 180 to press-fit the specimen under an arbitrary load. The driving unit 130 may include a motor for controlling the movement of the indenter 180. For example, the drive unit 130 may use an AC servomotor that is stable to external loads and overloads, and capable of precise control. By using an AC servo motor, the influence of possible risk factors such as external vibration can be eliminated. The AC servomotor included in the driving unit 130 is not limited thereto, but may be any device capable of moving the indenter 180.

The sensor unit 140 measures the indentation displacement and the indentation load according to the indentation of the indenter 180. The sensor unit 140 includes a displacement sensor and a load sensor.

The displacement sensor measures the indentation displacement, which is the indentation depth, when the indenter 180 indents the specimen. The displacement sensor uses, but is not limited to, a Linear Variable Displacement Transducer (LVDT).

The load sensor measures the indentation load applied by the indenter 180 to the specimen when the indenter 180 removes the indentation applied after the indentation 180 presses the specimen.

The sensor unit 140 measures the indentation displacement and the indentation load by using the displacement sensor and the load sensor as described above, and transmits the same to the calculation unit 160.

The imaging unit 150 acquires an image of the indenter 180 or the specimen. The imaging unit 150 is located at the bottom of the hardness and tensile properties measuring device is located on the indenter 180. The imaging unit 150 is composed of one or more camera lenses. In the embodiment of the present invention, two camera lenses are built in the hardness and tensile property measuring apparatus. Two camera lenses may be mounted as shown in FIG. Referring to Figure 2, it can be seen the position where the camera lens of the hardness and tensile properties measuring apparatus is built. The body of the hardness and tensile property measuring device, that is, the indenter 180 is mounted on the protruding surface.

The imaging unit 150 performs image processing so that the image obtained by acquiring the image of the indenter 180 or the specimen through the camera lens can be visually confirmed through the output unit 170.

The imaging unit 150 transmits the image of the indenter or the specimen processed image to the output unit 170.

The calculator 160 calculates tensile property values and hardness values.

The calculator 160 generates image information by using an image processed through the image unit 150. In this case, the image information includes distance information of the press-in position of the camera lens and the specimen from the image, distance information of the indenter 180 and the specimen, diagonal length information of the indentation mark, and the like.

The calculation unit 160 may be configured to display image information such as distance information of the camera lens and the press-in position of the specimen, distance information of the indenter 180 and the specimen, and diagonal length information of the press-in mark from the image displayed on the output unit 170. It can be calculated in units of pixels. In addition, the calculator 160 may convert the image information calculated in pixel units into an actual length.

The calculation unit 160 calculates the tensile characteristic value and the hardness value of the specimen using the indentation displacement, the indentation load, and the generated image information received from the sensor unit 140.

The calculator 160 may calculate load-displacement curve data using the indentation displacement and the indentation load. The calculation unit 160 may calculate the tensile characteristic value of the specimen using the calculated load-displacement curve data.

The calculator 160 may calculate the hardness value of the specimen using the image information and the indentation load.

Here, the hardness value of the specimen may be calculated by [Equation 1].

Here, Hv is the hardness value of the specimen, P is the indentation load applied to the specimen, d is the diagonal left and right average value of the indentation mark, a is the facing angle of the indenter 180.

Here, the left and right diagonal average values of the indentation marks are expressed as shown in [Equation 2].

은 압입 자국의 좌 대각선,

는 압입 자국의 우 대각선이다.here

Is the left diagonal of the indentation,

Is the right diagonal of the indentation mark.

In addition, when the facing angle of the indenter 180 is 136 ㅀ, the hardness value of the specimen may be expressed as shown in [Equation 3].

The calculation unit 160 is a formula for calculating the tensile characteristic value or the hardness value of the specimen as described above is not limited thereto, but is an embodiment of the present invention.

The calculation unit 160 outputs the tensile property value and the hardness value of the calculated specimen to the output unit 170.

The output unit 170 may output the received image of the specimen and the indenter 180, the tensile characteristic value and the hardness value of the specimen on the screen.

Figure 3 is an exemplary view showing a method for controlling the position of the indenter according to an embodiment of the present invention.

Referring to FIG. 3, the hardness and tensile property measuring apparatus may control the position of the indenter using the acquired image. That is, the position h of the indenter can be controlled by using the indentation position L1 of the camera lens and the specimen and the indentation initial position L of the camera lens through the obtained image.

4 is an exemplary view illustrating a method of measuring a diagonal length of an indentation mark according to an exemplary embodiment of the present invention.

Referring to FIG. 4, an image acquired through two camera lenses of the hardness and tensile property measuring apparatus is used. The hardness and tensile properties measuring device detects the pixels of the area corresponding to the indentation marks from the acquired image. The hardness and tensile property measuring apparatus may calculate the actual diagonal lengths a and b of the indentation marks using L1 and L2, which are the distance between the detected pixel, each camera lens, and the indentation marks.

5 is a flowchart illustrating a method of measuring hardness and tensile properties according to an embodiment of the present invention.

Referring to FIG. 5, in operation S500, the hardness and tensile property measuring apparatus acquires images of the specimen and the indenter. Here, the specimen is one in which polishing such as electrolytic polishing or polishing is performed. The hardness and tensile property measuring device may acquire images of the specimen and the indenter using the built-in camera lens and output them to the screen.

In step S510, the hardness and tensile property measuring device moves the indenter to the indentation position of the specimen. By checking the image obtained in step S500 and output to the screen, the indenter may be located at the indentation position of the specimen. At this time, when the indenter is located at the indentation position of the specimen, the moving distance of the indenter can be calculated. That is, the distance between the initial position of the indenter and the specimen can be calculated.

In operation S520, the hardness and tensile property measuring device presses the specimen using the indenter. That is, the hardness and tensile properties measuring device can be press-fitted by applying a load to the specimen to lower the indenter vertically. The hardness and tensile properties measuring device can press-fit the specimen by a preset value. Here, the set value may be an indentation speed or an indentation displacement.

In operation S530, the hardness and tensile property measuring apparatus may remove the indentation applied to the specimen through the indenter. The hardness and tensile property measuring device can move the indenter by a certain distance by removing the constant load after the indenter is moved by the set value.

Steps S520 and S530 may be repeatedly performed. For example, the hardness measuring device may be set to a maximum indentation depth of 100um, 10 times the number of repetitions. At this time, the hardness and tensile properties measuring apparatus is set to the indentation rate 0.1mm / min, one time moving depth to 10um, it can be repeated 10 times.

In step S540, the hardness and tensile properties measuring device measures the indentation displacement and load. The hardness and tensile property measuring device can measure the indentation depth and the indentation load of the indenter using a displacement sensor and a load sensor. The hardness and tensile property measuring apparatus may measure the indentation depth and the indentation load each time step S520 and step S530 are repeatedly performed.

In operation S550, the hardness and tensile property measuring apparatus acquires an image of the specimen after indentation. After measuring the hardness and tensile properties of the specimen by using the indenter, the image of the specimen having the indentation trace may be obtained.

In operation S560, the hardness and tensile property measuring device generates image information. The hardness and tensile properties measuring device generates the image information through the image of the specimen having the obtained indentation traces. Here, the image information may include at least one of the distance between the camera lens and the press-in position of the specimen, the distance between the press-in and the specimen, and the diagonal length of the press-in mark.

In operation S570, the hardness and tensile property measuring apparatus calculates tensile property values and hardness values of the specimen using image information, indentation displacement, and indentation load.

The hardness and tensile property measuring device can calculate the load-displacement curve data using the indentation displacement and the indentation load. The hardness and tensile properties measuring device can calculate the tensile property value of the specimen using the calculated load-displacement curve data.

In addition, the hardness and tensile properties measuring device may calculate the hardness value of the specimen using the image information and the indentation load.

In operation S580, the apparatus for measuring hardness and tensile properties may output an image obtained after pressing the specimen through the screen, the calculated tensile characteristic value, and a warning value.

6 is an exemplary view showing a hardness measurement screen according to an embodiment of the present invention.

Referring to FIG. 6, the apparatus for measuring hardness and tensile properties may output an image acquired when measuring hardness to a portion of an image display screen. Therefore, the distance between the indenter and the specimen can be confirmed from the image display screen.

In addition, the hardness and tensile property measuring apparatus may output the calculated hardness value and tensile property value to the test information screen portion.

The configuration of the above-described hardness measurement screen can be easily changed by those skilled in the art.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art to which the present invention pertains without departing from the spirit and scope of the present invention as set forth in the claims below It will be appreciated that modifications and variations can be made.

110: input unit 120: control unit
130: driving unit 140: sensor unit
150: video unit 160: calculator
170: output unit 180: indenter

Claims (8)

In the hardness and tensile properties measuring device for measuring the hardness of the specimen,
An imaging unit for imaging the image of the indenter and the specimen;
A driving unit which moves the indenter and presses it into the specimen using the acquired indenter and the image of the specimen;
Sensor unit for measuring the indentation displacement and indentation load according to the indentation of the indenter;
Comprising a calculation unit for calculating a tensile characteristic value or a hardness value using at least one of the image of the specimen, the indentation displacement and the indentation load,
The calculation unit
Hardness and tensile properties measuring apparatus characterized in that for calculating the hardness value using the diagonal average value of the indentation marks calculated from the indentation load and the image of the specimen.
The method of claim 1,
The calculation unit
And the tensile characteristic value is calculated using a load-displacement curve using the measured indentation load and the indentation displacement.
delete The method of claim 1,
The hardness value is

<kgf / mm2>
Hardness and tensile property measuring apparatus characterized by the above-mentioned.
(Where Hv is the hardness value of the specimen, P is the indentation load applied to the specimen, d is the left and right diagonal mean value of the indentation mark, and a is the facing angle of the indenter)
In the method for measuring the hardness of the specimen using a hardness and tensile properties measuring device,
Obtaining images of the specimen and indenter;
Fixing the indenter to the indentation position of the specimen;
Indenting the specimen by the indenter;
Removing the indentation applied to the specimen through the indenter;
Measuring an indentation displacement and an indentation load according to the indentation;
Acquiring an image of a specimen after the indentation; And
Comprising the step of calculating the tensile characteristic value and the hardness value of the specimen using the image, the indentation displacement and the indentation load,
The hardness value is
Hardness and tensile properties measuring method characterized in that it is calculated using the diagonal average value of the indentation marks calculated from the indentation load and the image of the specimen.
The method of claim 5,
The tensile property value is
And the tensile characteristic value is calculated using a load-displacement curve using the measured indentation load and the indentation displacement.
delete The method of claim 5,
The hardness value is

<kgf / mm2>
Hardness and tensile property measurement method characterized in that.
(Where Hv is the hardness value of the specimen, P is the indentation load applied to the specimen, d is the left and right diagonal mean value of the indentation mark, and a is the facing angle of the indenter)

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