KR101682692B1

KR101682692B1 - Cracklength measuring device and method

Info

Publication number: KR101682692B1
Application number: KR1020150064716A
Authority: KR
Inventors: 남승훈; 전상구; 류권상; 권오헌
Original assignee: 한국표준과학연구원
Priority date: 2015-05-08
Filing date: 2015-05-08
Publication date: 2016-12-07
Also published as: KR20160131725A

Abstract

The present invention relates to a test apparatus for applying heat and load to a test piece; A crack measuring unit for measuring a crack occurring in the test piece; And a controller for controlling the heat and the load applied to the test piece, and a crack measuring method using the same. Accordingly, cracks and crack propagation due to external loads applied to the material in the external environment where the material is exposed to high temperature can be confirmed.

Description

TECHNICAL FIELD [0001] The present invention relates to a crack measuring apparatus,

The present invention relates to a crack measuring apparatus and a crack measuring method. And more particularly, to a crack measuring apparatus and a crack measuring method capable of confirming cracks and crack growth of a material exposed to an external high temperature.

In general, in order to measure the crack length of the test specimen measured in the existing fracture toughness and fatigue crack growth test, an optical microscope having a deep depth is installed on the surface of the specimen, and the length of the microscope is measured .

A related invention is a microscope-mounted tabletop bending tester of Korean Registered Patent No. 10-1292006 (Mar. 31, 2013).

The microscope-mounted tabletop bending tester is characterized in that the load applied to the specimen is measured and the crack of the specimen is measured through a microscope.

However, the microscope-mounted bench-top bend tester has difficulty in confirming the progress direction of real-time cracks by measuring the cracks of the specimen only with a microscope.

In addition, there is a problem that it is difficult to obtain an accurate crack length value because the probability of error increases due to the degree of parallelism of the microscope moving direction with respect to the specimen and the individual difference of the microscope operator.

In particular, there is a difficulty in identifying cracks and crack growth directions occurring in the material in an environment where the material is exposed to external high temperatures.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a crack measuring apparatus and a crack detecting apparatus capable of confirming cracks and crack growth of a material due to an external load applied to a material in an external environment, And to provide a measurement method.

More specifically, the present invention provides a crack measuring apparatus and a crack measuring method capable of recognizing cracks, crack length, and crack propagation that may occur in a material due to an external load when one side of the material is exposed to a high temperature.

It is also an object of the present invention to provide a crack measuring apparatus and a crack measuring method capable of measuring an internal crack and crack propagation between materials having a laminated structure by using an optical measuring method.

According to a preferred embodiment of the present invention, the above object is achieved by a test apparatus for testing a test piece for applying heat and load to the test piece; A crack measuring unit for measuring a crack occurring in the test piece; And a control unit for adjusting the heat and the load applied to the test piece.

The test unit may include: a housing having a housing space and a heat transfer hole; A high temperature part installed in the accommodation space for radiating heat to the heat transfer hole; And a load applying unit for applying a load to the test piece, and the test piece may be disposed adjacent to the heat transfer hole.

Here, the high temperature section may include a lamp; And a high temperature furnace.

A coating layer may be formed inside the high-temperature furnace.

The apparatus may further include a cooling device for cooling the outside of the high-temperature furnace.

The housing may include a body having an opening formed in the receiving space and at one side thereof; And a cover formed to cover the opening and having the heat transfer hole, and the cover may further include a support member for supporting one side of the test piece.

The apparatus may further include a temperature sensor for measuring a temperature of the heat transfer hole.

The apparatus may further include a jig provided between the test piece and the load applying unit to present the directionality of the load.

Here, the fixture may be formed of inconel material.

The crack measuring unit may include at least one of a microscope and a camera.

Here, the crack measuring unit may further include a microscope, a body of the crack measuring unit provided with the camera, and a moving unit for moving the body of the crack measuring unit.

The moving unit includes: a vertical moving unit for vertically moving the crack measuring unit main body; And a left and right moving unit for moving the main body of the crack measuring unit left and right.

The crack measuring unit may further include a meter for displaying a moving distance of the microscope moved by the moving unit.

Meanwhile, the test portion may further include a heat prevention portion.

Here, the heat prevention portion may include a coupling portion movably installed in the load applying portion; And a heat prevention plate provided on one side of the coupling portion.

The control unit may further include a display unit for displaying an image photographed by the crack measuring unit.

Meanwhile, the test piece may have a structure in which at least two materials are laminated.

According to a preferred embodiment of the present invention, the above object is achieved by a method for manufacturing a crack, comprising the steps of: Applying heat at a predetermined temperature to one side of the test piece using the crack measuring apparatus; Applying a predetermined load to the test piece; And a step of confirming cracks occurring in the test piece, wherein the crack measuring device comprises: a test part for applying heat and load to the test piece; A crack measuring unit for checking a crack generated in the test piece by a load by the test unit; And a controller for controlling the heat and the load applied to the test piece.

The method may further include measuring a propagation length of the crack using the crack measuring unit.

Here, the crack measuring unit may include a microscope; A moving unit for moving the microscope; And a meter for indicating the moving distance of the microscope.

According to a preferred embodiment of the present invention, the above object is achieved by a method for manufacturing a crack, comprising the steps of: Applying heat at a predetermined temperature to one side of the test piece using the crack measuring apparatus; Applying a predetermined load to the test piece; And a step of storing an image of a crack progression process, wherein the crack measurement device comprises: a test part for applying heat and load to the test piece; A camera for storing an image of a crack progression occurring in the test piece due to a load by the test unit; And a control unit for adjusting the heat and the load applied to the test piece.

Here, the test piece may have a structure in which at least two materials are laminated.

The crack measuring apparatus and the crack measuring method according to an embodiment of the present invention having the above-described structure can detect cracks, crack lengths and crack propagation that may occur in the material due to external load when one side of the material is exposed to high temperature can do.

Also, in order to form a high temperature environment in the test material, it is possible to measure cracks and crack progression of the material exposed to high temperature at room temperature without conducting the experiment in the high temperature furnace.

1 is a view showing a crack measuring apparatus according to a preferred embodiment of the present invention,
FIG. 2 is a view showing a testing unit of a crack measuring apparatus according to a preferred embodiment of the present invention,
3 is a sectional view showing the line AA in Fig. 2,
4 is a view showing a test piece installed in a test section of a crack measuring apparatus according to a preferred embodiment of the present invention,
5 is a view showing a support member of a crack measuring apparatus according to a preferred embodiment of the present invention,
FIG. 6 is a view showing a heat prevention part of a crack measuring apparatus according to a preferred embodiment of the present invention,
7 is a view showing a test piece to which heat and load are applied by a crack measuring apparatus according to a preferred embodiment of the present invention,
8 and 9 are views showing a crack measuring unit of a crack measuring apparatus according to a preferred embodiment of the present invention,
10 is a view showing a specimen taken by a camera of a crack measuring apparatus according to a preferred embodiment of the present invention,
11 is a view showing a left and right meter of a crack measuring apparatus according to a preferred embodiment of the present invention,
12 and 13 are views showing a crack measurement method according to a preferred embodiment of the present invention.

The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated and described in the drawings. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terms including ordinal, such as second, first, etc., may be used to describe various elements, but the elements are not limited to these terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the second component may be referred to as a first component, and similarly, the first component may also be referred to as a second component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

In the description of the embodiments, when an element is described as being formed "on or under" another element, the upper or lower (lower) (on or under) all include that the two components are in direct contact with each other or that one or more other components are indirectly formed between the two components. Also, when expressed as 'on or under', it may include not only an upward direction but also a downward direction based on one component.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings, wherein like or corresponding elements are denoted by the same reference numerals, and redundant description thereof will be omitted.

The crack measuring apparatus 1 according to the preferred embodiment of the present invention can confirm cracks and crack growth directions due to an external load applied to a material in an external environment where the material is exposed to an external high temperature.

More specifically, the crack measuring apparatus 1 can measure the internal cracks and crack progression of the test piece 2 by applying heat and load to the test piece 2 formed using the material, and using the optical measurement method.

Here, the test piece 2 may be formed to have a laminated structure using at least two materials. Accordingly, it is possible to measure or study cracks and crack progression occurring between the materials by heat and load in the test piece (2) having a laminated structure formed by using at least two materials.

1 to 11, a crack measuring apparatus 1 according to a preferred embodiment of the present invention may include a test unit 100, a crack measuring unit 200, and a controller 300.

The test part 100 can apply heat and load to the test piece 2.

2 to 7, the test part 100 includes a housing 110 on which a test piece 2 is installed, a high temperature part 120 for applying heat to the test piece 2, A load applying unit 130, a jig 140, and a heat prevention unit 150. [

The housing 110 may include a body 111, a cover 112, a receiving space 113, and a heat transfer hole 114, as shown in FIGS. In addition, the housing 110 allows the heat generated through the high temperature portion 120 to be concentrated on the test piece 2 through the heat transfer holes 114. Accordingly, the external device such as the control unit 300 can be prevented from being damaged by the housing 110. [

As shown in FIGS. 2 and 3, the main body 111 may be formed in a cylindrical shape having an opening formed at one side thereof. Accordingly, a receiving space 113 may be provided in the main body 111. [ Here, the main body 111 is formed in a cylindrical shape, but is not limited thereto. The main body 111 may be formed in various shapes such as a triangular barrel and a rectangular barrel having a receiving space 113 and the opening therein to be.

The cover 112 may be installed in the main body 111 to cover the opening. A heat transfer hole 114 may be formed in the cover 112.

Further, the cover 112 may further include a support member 115 for supporting one side of the test piece 2, as shown in Figs. 3 and 4. Fig. Here, the support member 115 may be formed of inconel which is a heat-resistant material. As a result, the support member 115 can be prevented from being deformed by heat, thereby improving the reliability of experimental data.

5, the support member 115 allows the test piece 2 to be disposed adjacent to the heat transfer hole 114 to minimize the influence of heat transmitted through contact with the cover 112, So that a load can be exerted only on the test piece 2 by the bushing 130 so that the bending test of the test piece 2 is possible.

The accommodation space 113 may be formed by a combination of the main body 111 and the cover 112. 2 and 3, the high temperature part 120 may be installed in the accommodation space 113. [

The high temperature part 120 may be installed in the internal space 113 of the housing 110 to generate heat to apply heat to the test piece 2 through the heat transfer hole 114.

The high temperature part 120 can apply a predetermined heat to the test piece 2 by the electric signal of the control part 300.

The high temperature section 120 may include a lamp 121 and a high temperature furnace 122 for generating heat. Here, the lamp 121 may be a halogen lamp, or a heater that generates heat in place of the lamp 121 may be used.

The high temperature furnace 122 can prevent heat loss of the heat generated through the lamp 121 and apply heat to the test piece 2 through heat reflection. Here, as the high-temperature furnace 122, a crucible or the like which is a heat resistant container can be used.

A coating layer 124 using Au or the like may be formed inside the high temperature furnace 122. That is, the coating layer 124 can improve heat loss prevention efficiency and heat reflection efficiency of the heat generated through the lamp 121.

On the other hand, a cooling channel 123 may be further formed on the outside of the high temperature furnace 122. The test section 100 may further include a cooling device (not shown) for moving the cooling water through the cooling channel 123. Accordingly, the high temperature furnace 122 can be cooled by the cooling water moving through the cooling channel 123. [

Since the outside of the high temperature furnace 122 can be cooled by the cooling water, an external device such as the control unit 300 can be prevented from being thermally damaged by the high temperature generated by the lamp 121. Further, the external device such as the control unit 300 can further minimize the influence of heat by the housing 110. [

That is, the crack measuring apparatus 1 can be operated without performing an experiment in a high-temperature furnace to form a high-temperature environment in the material by the housing 110, the high-temperature furnace 122 and the cooling water having the heat- Can measure cracks and crack propagation directions of material exposed to high temperature at room temperature.

The load applying section 130 can apply a load to the test piece 2. Here, the load applying unit 130 may apply a preset load to the test piece 2 by the electrical signal of the controller 300. [

2 and 3, the load applying unit 130 may be installed on the upper portion of the test piece 2 and may be formed by using a load applying member 131 provided at one end of the load applying unit 130 A load can be applied to the test piece (2). For example, the load applying member 131 can be raised and lowered by a lifting device 132 using a motor, gear, or the like.

On the other hand, the jig 140 is installed on the upper portion of the test piece 2 and is pressed by the load applying member 131, so that the load can be applied to the test piece 2. [

The jig 140 may include a jig body 141 and a jig member 142. Here, the jig body 141 and the jig member 142 may be formed of heat-resistant inconel material. As a result, the jig member 142 can be prevented from being deformed by heat, thereby improving the reliability of the experimental data.

The jig 140 can apply a load applied by the load applying unit 130 to the test piece 2. The jig 140 can provide the directionality of the load to the test piece 2 using the jig member 142.

For example, as shown in FIG. 4, the four-point bending test may be performed using two jig members 142 and support members 114, but the present invention is not limited thereto. Point bending test or the like may be performed depending on the number and shape of the jig members 142.

That is, the crack measuring apparatus 1 can use the jig 140 to apply various loads to the test piece 2 according to the test purpose.

Although the crack measuring apparatus 1 uses the jig 140 as an example, the present invention is not limited thereto. The load may be applied to the test piece 2 using only the load applying member 131 to be.

Referring to FIGS. 2, 6 and 7, the heat prevention part 150 may prevent heat leaking through the heat transfer hole 114 from affecting other devices such as the control part 300.

The heat prevention part 150 may be movably installed in the load applying part 130 and may include a heat prevention plate 151 and a coupling part 152.

The heat prevention plate 151 prevents heat leaking through the heat transfer hole 114 from affecting other devices such as the control unit 300 and the coupling unit 152 prevents the heat prevention plate 151 from being heated by the load applying unit 151. [ (Not shown).

Here, the engaging portion 152 may include a first engaging portion 152a and a second engaging portion 152b on which the heat prevention plate 151 is installed, and the first engaging portion 152a and the second engaging portion 152b (152b) may be installed in the load applying unit (130) through a fastening member such as a bolt or a nut. Since the engaging portion 152 can be installed in the load applying portion 130 through the fastening member, the user can adjust the mounting position.

Meanwhile, the test unit 100 may further include a temperature sensor 160.

The temperature sensor 160 can measure the temperature of the heat transfer hole 114. The temperature sensor 160 may transmit an electrical signal including the measured temperature information to the controller 300. [ Accordingly, the control unit 300 can control the heat applied to the test piece 2 by controlling the high temperature unit 120. Here, the temperature sensor 160 may be installed on one side of the inner surface of the cover 112 on which the heat transfer hole 114 is formed.

In the present invention, the temperature sensor 160 senses the heat radiated through the heat-conducting holes 114, but the present invention is not limited thereto. The heat- It is of course possible to directly measure the temperature of the sample 2. More specifically, the temperature sensor 160 may be installed to measure the temperature of one region of the test piece 2 heated by the heat transmitted through the heat transfer hole 114.

The crack measuring unit 200 can measure cracks, crack propagation directions, and crack propagation processes in the test piece 2 to which heat and load are applied, by using an optical measurement method.

7 to 9, the crack measuring unit 200 includes a microscope 210, a camera 220, a crack measuring unit main body 230 provided with a microscope 210 and a camera 220, (240), a moving part (250), a vertical moving lever (260), a horizontal moving lever (270), and a meter. Here, the meter may include a vertical meter 280 and a left and right meter 290.

The crack measuring unit 200 of the crack measuring apparatus 1 is an example of a crack measuring unit main body 230 provided with a microscope 210 and a camera 220. However, It is needless to say that only one of the cameras 220 may be installed.

The microscope 210 may include an eyepiece lens 211 through which the user can confirm in real time the cracks generated in the test piece 2, the direction of the crack progression, and the crack progression process.

The eyepiece 211 may be formed with a scale, a cross-cross line or the like, and the scale or cross-cross line may be used to measure the position and crack length of the crack formed in the test piece 2.

The camera 220 can acquire an image of the crack propagation process formed on the test piece 2. That is, the camera 220 acquires a crack image formed on the test piece 2 or an image of the crack propagation process, so that the user can visually confirm the crack or crack propagation process formed on the test piece 2.

Here, the camera 220 may be a charge-coupled device camera (CCD camera).

Therefore, as shown in FIG. 10, the crack measuring apparatus 1 can acquire a crack image of the test piece 2 by using the camera 220. FIG.

The focus control lever 240 may control the movement of the crack measurement unit main body 230 to adjust the focus of the microscope 210 and the camera 220. [

The moving unit 250 can move the crack measuring unit main body 230 up, down, left, and right. The microscope 210 and the camera 220 of the crack measuring apparatus 1 are moved together but the present invention is not limited thereto and the microscope 210 and the camera 220 can be moved Of course.

Referring to FIGS. 8 and 9, the moving unit 250 may include a vertical moving unit 251 and a left and right moving unit 252.

The upper and lower moving levers 260 can adjust the upward and downward movement distance of the crack measuring unit main body 230. The upper and lower moving levers 260 can move the upper and lower crack measuring unit main bodies 230 up and down. The up-and-down meter 280 displays a vertical movement distance of the crack measuring unit main body 230.

The left and right moving parts 252 can move the crack measuring part main body 230 left and right and the left and right moving levers 270 can adjust the left and right moving distance of the crack measuring part main body 230. The right and left moving distance of the crack measuring unit main body 230 is displayed on the left and right meters 290.

Therefore, when a bending load is applied to the test piece 2 and cracks are generated in the test piece 2, the center of the cross line shown on the eyepiece 211 of the microscope 210 is aligned with one side of the crack, 260 or the left / right moving lever 270 to move the center of the cross line to a position where the crack is to be detected. As shown in FIG. 11, the length of the crack can be measured by using the vertical meter 280 or the left and right meter 290.

The control unit 300 controls the high temperature unit 120 and the load application unit 130 to apply predetermined heat and load to the test piece 2. The control unit 300 may control the high temperature unit 120 based on the temperature information transmitted through the temperature sensor 160. [

Meanwhile, the controller 300 may include a display unit 310 for displaying image information photographed by the crack measuring unit 200. The user can recognize the process of cracks and cracks through the display unit 310.

Hereinafter, a crack measuring method (S1) using the crack measuring apparatus 1 according to a preferred embodiment of the present invention will be described. In the description of the crack measuring method (S1), description of the same components mentioned in the crack measuring apparatus (1) will be omitted.

Referring to FIG. 12, a crack measuring method (S1) includes a step of installing a test piece on a crack measuring apparatus (S10), a step of applying heat to a predetermined temperature on one side of the test piece using the crack measuring apparatus (S30) of applying a predetermined load to the test specimen, a step (S40) of detecting a crack occurring in the specimen, and a step (S50) of measuring a progress length of the crack.

In the step (S10) of installing the test piece on the crack measuring apparatus, the test piece (2) can be installed in the crack measuring apparatus (1). Here, the test piece 2 may be formed to have a laminated structure using at least two materials.

In the step S20 of applying heat at a predetermined temperature to one side of the test piece using the crack measuring apparatus, heat can be applied to the test piece 2 using the high temperature portion 120. [ Also, it can be confirmed that heat is applied to the test piece 2 through the temperature sensor 160 at a predetermined temperature.

In the step S30 of applying a predetermined load to the test piece, a predetermined load may be applied to the test piece 2 by using the load applying unit 130. [

In step S40, cracks occurring in the test piece 2 can be confirmed through the microscope 210 of the crack measuring unit 200 by the load.

When a bending load is applied to the test piece 2 and cracks are generated in the test piece 2 in step S50 of measuring the advance length of the crack, The center of the cross line is aligned and the center of the cross line is moved to a position to detect the crack by using the up / down movement lever 260 or the left / right movement lever 270. Then, the advance length of the crack can be measured using the meter.

Hereinafter, a crack measuring method (S2) using the crack measuring apparatus 1 according to a preferred embodiment of the present invention will be described. However, in explaining the crack measuring method (S2), the description of the same constituting steps mentioned in the crack measuring method (S1) will be omitted.

Referring to FIG. 13, the crack measuring method (S2) includes installing a test piece on a crack measuring apparatus (S10), applying heat to a predetermined temperature on one side of the test piece using the crack measuring apparatus A step S30 of applying a predetermined load to the test piece, and a step S60 of storing an image of the progress of cracking.

In the step S60 of storing the progress of the crack, the image of the crack propagation process formed on the test piece 2 by the load can be obtained. The acquired image may be stored in a storage medium or the like. The camera 220 may be used in acquiring the image.

The crack measuring apparatuses 1 and the crack measuring methods S1 and S2 may include a housing 110 having a heat transfer hole 114 and a test piece exposed to a high temperature at a room temperature using the high temperature furnace 122 2) and the direction of crack propagation can be measured.

In addition, the microscope 210 can be used to check the length of cracks and crack propagation in real time.

Further, the camera 220 can be used to confirm cracks and progress of cracks.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the appended claims. It will be understood that the present invention can be changed. It is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

1: Crack measuring device 2: Test piece
100: Test section 110: Housing
120: high temperature part 130: load applying part
140: jig 150: heat branch
160: Temperature sensor 200: Crack measuring part
210: Microscope 220: Camera
230: Crack measuring unit main body 240: Focusing lever
250: moving part 260: up and down moving lever
270: left / right movement lever 280: vertical meter
290: left and right meter 300:
310:

Claims

A test section for applying heat and load to the test piece;
A crack measuring unit for measuring a crack occurring in the test piece; And
And a controller for controlling the heat and the load applied to the test piece,
The testing unit includes:
A cylindrical housing having a housing space formed therein and a heat transfer hole formed at one side thereof;
A high temperature part installed in the accommodation space, the high temperature part being disposed below the heat transfer hole; And
And a load applying unit for applying a load to the test piece,
The test piece is disposed adjacent to an upper portion of the heat transfer hole,
And the heat radiated from the high temperature part is applied to the test piece through the heat transfer hole.

delete

The method according to claim 1,
The high-
A lamp for generating heat and applying heat to the test piece; And
Heat-resistant high-temperature furnace,
Wherein the lamp is disposed inside the high temperature furnace to prevent heat loss of heat generated through the lamp.

The method of claim 3,
Wherein a coating layer is formed inside the high-temperature furnace.

The method of claim 3,
And a cooling flow passage through which the cooling water moves is further formed on the outside of the high temperature furnace.

The method according to claim 1,
The housing includes:
A main body having an accommodating space therein and an opening formed at one side thereof; And
And a cover provided with the heat transfer hole and covering the opening,
Wherein the cover further comprises a support member for supporting one side of the test piece.

The method according to claim 1,
And a temperature sensor for measuring the temperature of the heat transfer hole.

The method according to claim 1,
And a jig provided between the test piece and the load applying part to present the directionality of the load applied to the test piece through the load applying part.

9. The method of claim 8,
Wherein the fixture is formed of an inconel material.

The method according to claim 1,
Wherein the crack measuring unit includes at least one of a microscope and a camera.

11. The method of claim 10,
Wherein the crack measuring unit further comprises a main body of the crack measuring unit provided with the microscope and the camera, and a moving unit moving the main body of the crack measuring unit.

12. The method of claim 11,
The moving unit
A vertically moving part for vertically moving the crack measuring part main body; And
And a left and right moving unit for moving the main body of the crack measuring unit to the left and right.

13. The method of claim 12,
Wherein the crack measuring unit further comprises a meter for displaying a moving distance of the microscope moved by the moving unit.

The method according to claim 1,
Wherein the test portion further includes a heat prevention portion.

15. The method of claim 14,
Wherein the heat prevention part includes: a coupling part movably installed in the load applying part; And
And a heat prevention plate provided on one side of the coupling portion.

The method according to claim 1,
Wherein the controller further comprises a display unit for displaying an image photographed by the crack measuring unit.

The method according to claim 1,
Wherein the test piece has a structure in which at least two materials are laminated.

Installing a test piece on a crack measuring apparatus;
Applying heat at a predetermined temperature to one side of the test piece using the crack measuring apparatus;
Applying a predetermined load to the test piece; And
And confirming cracks occurring in the test piece,
The crack measuring apparatus includes:
A test section for applying heat and load to the test piece;
A crack measuring unit for checking a crack generated in the test piece by a load by the test unit; And
And a controller for adjusting the heat and the load applied to the test piece,
The crack measuring apparatus includes:
A test portion for applying heat and load to the test piece;
A crack measuring unit for measuring a crack occurring in the test piece; And
And a controller for controlling the heat and the load applied to the test piece,
The testing unit includes:
A cylindrical housing having a housing space formed therein and a heat transfer hole formed at one side thereof;
A high temperature part installed in the accommodation space, the high temperature part being disposed below the heat transfer hole; And
And a load applying unit for applying a load to the test piece,
The test piece is disposed adjacent to an upper portion of the heat transfer hole,
And heat radiated from the high temperature part is applied to the test piece through the heat transfer hole.

19. The method of claim 18,
And measuring a propagation length of the crack using the crack measuring unit.

20. The method of claim 19,
Wherein the crack measuring unit comprises:
microscope;
A moving unit for moving the microscope; And
And a meter for indicating a moving distance of the microscope.

Installing a test piece on a crack measuring apparatus;
Applying heat at a predetermined temperature to one side of the test piece using the crack measuring apparatus;
Applying a predetermined load to the test piece; And
And storing the image of the crack progression image,
The crack measuring apparatus includes:
A test portion for applying heat and load to the test piece;
A crack measuring unit for measuring a crack occurring in the test piece; And
And a controller for controlling the heat and the load applied to the test piece,
The testing unit includes:
A cylindrical housing having a housing space formed therein and a heat transfer hole formed at one side thereof;
A high temperature part installed in the accommodation space, the high temperature part being disposed below the heat transfer hole; And
And a load applying unit for applying a load to the test piece,
The test piece is disposed adjacent to an upper portion of the heat transfer hole,
And heat radiated from the high temperature part is applied to the test piece through the heat transfer hole.

22. The method according to any one of claims 18 to 21,
Wherein the test piece has a structure in which at least two materials are laminated.