WO2018155790A1

WO2018155790A1 - Test piece for testing shear of metal material and shear testing device for test piece

Info

Publication number: WO2018155790A1
Application number: PCT/KR2017/013369
Authority: WO
Inventors: 이제명; 김명성; 김슬기; 김정현
Original assignee: 부산대학교 산학협력단
Priority date: 2017-02-23
Filing date: 2017-11-22
Publication date: 2018-08-30
Also published as: KR101866408B1

Abstract

The present invention relates to a test piece for testing the shear of a metal material and a shear testing device for the test piece, the test piece being capable of performing a test according to a pure shear load condition, a tensile-shear load condition, and a tensile load condition by enabling a change in a mounting angle on a jig of the shear testing device. According to the present invention, the test piece for testing the shear of the metal material comprises: a first fixing part having a deformable part having a plurality of openings penetratively formed at both sides of the center portion thereof, such that shear force or tensile force is applied between the openings, and having two separation holes cut while extending from each opening to the edge thereof, such that the first fixing part is coupled to a first jig of the shear testing device with respect to the separation hole; and a second fixing part coupled to a second jig of the shear testing device. According to the present invention, the shear testing device for testing the shear of the test piece comprises: the first jig to which the first fixing part of the test piece is separably coupled; a second jig disposed at the opposite side of the first jig, and to which the second fixing part of the test piece is separably coupled; and a tensile deformation applying means for pulling the first jig and the second jig in a direction away from each other.

Description

Shear test specimen of metal material and shear test apparatus of the specimen

The present invention relates to a shear test apparatus of a metal material, and more particularly, it is possible to change the angle to be mounted on the jig of the shear test apparatus, the shear shear (Pure shear) load conditions, tension-shear load (Tensile-shear) load The present invention relates to a test specimen for shear test of a metallic material and a shear test apparatus for the test specimen to enable the test according to the conditions and the tensile load conditions.

In general, the material tensile test of the metal material is performed to analyze the mechanical behavior and failure characteristics, it is possible to obtain the elastic modulus, yield strength, tensile strength and elongation. Many industries perform material tension tests and design various machines and structures based on the data obtained from these tests.

The easiest way to define the local failure of a structure is to use the strain at break obtained through uniaxial tensile testing. However, the material's failure strain is different depending on the stress triaxiality and the rod angle of the material. Therefore, in order to evaluate the structural health, failures due to various stress triaxial ratios and rod angles are considered. Design is a must.

To date, material unit tests have been proposed for various load characteristics and test equipment has been proposed and developed. However, no equipment has been developed to test failures due to various stress triaxial ratios and load angles. It is not true.

The present invention is to solve the above problems, the object of the present invention is to enable the change of the angle mounted on the jig of the shear test apparatus, the shear shear (Pure shear) load conditions, Tensile-shear The present invention provides a test specimen for shear test of a metallic material and a shear test apparatus for the test specimen so that tests according to load conditions and tensile load conditions can be performed.

Shear test specimens of the metal material according to the present invention for achieving the above object, a plurality of openings are formed on both sides of the central portion to form a deformation portion is applied to the shear force or tensile force between the openings, respectively The first fixing part coupled to the first jig of the shear test apparatus and the second jig of the shear test apparatus are provided with two separation holes which are cut while extending from the opening to the edge. It is characterized by consisting of two fixed parts.

Shear test apparatus according to the present invention for shearing the test body, the first jig to which the first fixing part of the test body is detachably coupled; A second jig disposed opposite the first jig and detachably coupled to a second fixing part of the test body; And tensile strain imparting means for pulling the first jig and the second jig in a direction away from each other.

According to the present invention, the angle of the test body can be mounted on the first jig and the second jig of the shear test apparatus by varying the angle, and the orientation of the deformation part of the test body is changed according to the angle at which the test body is mounted on the shear test apparatus. The load conditions vary. Therefore, the shear test can be performed by applying shear and / or tensile force under various load conditions.

1 is a front view showing a test specimen for a shear test of a metal material according to an embodiment of the present invention.

2 is a perspective view showing a shear test apparatus according to an embodiment of the present invention.

3 is a front view of the shear test apparatus shown in FIG.

4 is a side view of the shear test apparatus shown in FIG.

5 is a sectional view showing the principal parts of a modification of the shear test apparatus shown in FIG. 2.

Figure 6 is a view showing a variety of shear test examples by the shear test apparatus shown in FIG.

Figure 7 is an exploded perspective view showing a jig of the shear test apparatus according to another embodiment of the present invention.

Hereinafter, a test specimen for a shear test of a metal material and a shear test apparatus of the test specimen according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Figure 1 shows a test specimen for a shear test of a metal material according to an embodiment of the present invention, the test specimen 10 of this embodiment is made of a disk shape having a constant thickness, the upper and lower portions of the first jig of the shear test apparatus, respectively ( 100 is detachably coupled to the second jig 200 (see FIG. 2) and the second jig 200 (see FIG. 2). The thickness of the test body 10 may be variously applied according to the type and design conditions of the material to be tested.

More specifically, the test body 10 of the present invention is formed so that the two openings 11 are penetrated at both sides of the central portion, the deformation portion 12 is applied between the opening 11, the shear force or tensile force is formed And two separation holes 13 cut from each opening 11 to the edge and coupled to the first jig 100 of the shear test apparatus based on the separation holes 13. It consists of a first fixing part 14 and a second fixing part 15 coupled to the second jig 200 of the shear test apparatus.

The first fixing part 14 and the second fixing part 15 are each made of a semi-circular flat plate and have a symmetrical shape with each other. In addition, each of the first fixing part 14 and the second fixing part 15 is provided with a plurality of coupling holes 16 coupled to the first jig and the second jig, respectively, at regular intervals along the circumferential direction. Here, the coupling holes 16 of the first fixing part 14 and the second fixing part 15 are preferably arranged at 10 ° intervals along the circumferential direction.

The opening 11 is formed in an approximately elliptical shape on both sides of the deformation part 12 formed in the center of the test body 10, the shape may be variously modified. In this embodiment the opening 11 also has a symmetrical shape with respect to the center point of the deformation 12.

The two separation holes 13 extend in a straight line in a radial direction at one corner portion of each opening 11 to have an incision groove shape that is opened outward at the outer periphery of the test body 10, that is, the edge portion. Thus, the test body 10 of the present invention is divided into the first fixing part 14 and the second fixing part 15 on the basis of the two separation holes 13, the first fixing part 14 and the second The fixing part 15 is connected to each other only by the center deformation part 12 so that a load is concentrated only on the deformation part 12 when a tensile force is applied to the first fixing part 14 and the second fixing part 15.

The separation hole 13 is preferably formed in the same line as the center of the deformation portion 12. This is because the first fixing part 14 and the second fixing part 15 partitioned by the separation hole 13 have a symmetrical shape with respect to the deformation part 12 on both sides of the deformation part 12. This is to cause the stress to be generated uniformly.

Test body 10 made of such a configuration is coupled to the first jig 100 and the second jig 200 of the shear test apparatus at different angles, thereby the aspect of the load applied to the deformation part 12 By varying, we can obtain the breakage condition equation for various stress triaxiality ratio and rod angle. This will be discussed in more detail in the description of the shear tester below.

Next, a shear test apparatus for testing the test body 10 of the present invention having the structure as described above and a shear test method using the same will be described.

2 to 4, the shear test apparatus of the present invention includes a first jig 100 to which the first fixing part 14 of the test body 10 is detachably coupled, and the first jig 100. The second jig 200 and the first jig 100 and the second jig 200 which are disposed opposite to each other and the second fixing part 15 of the test piece 10 is detachably coupled to each other are separated from each other. Tensile strain imparting means (not shown).

The first jig 100 and the second jig 200 are connected to a device capable of applying a load in a universal testing machine (UTM), that is, a tensile strain applying means to exert a tensile force on the test body 10. It is configured to be able to combine by changing the angle of the test body (10).

In this embodiment, the first jig 100 is connected to the first clamping block 110 of two pairs and the first clamping block 110 are coupled to the first fixing portion 14, respectively. The first holder block 120 and the first connection block 130 for connecting the first holder block 120 with the tensile strain applying means.

The second jig 200 is a second clamping block 210 of two sets coupled to the second fixing part 15 and a second holder for interconnecting the two second clamping block 210 Block 220, and the second connecting block 230 for connecting the second holder block 220 with the tensile strain imparting means.

The first clamping block 110 formed of two sets is slidably installed in the first holder block 120 in the width direction so that the first fixing part 14 of the test body 10 is interposed between the first clamping blocks 110. The first clamping block 110 may be fixed to the both sides of the first fixing part 14 in a state where it is disposed. In addition, the two clamping blocks 210 formed of two sets are also slidably installed in the second holder block 220 in the width direction so that the second fixing part 15 of the test body 10 is between the second clamping blocks 210. ) May be fixed to the second clamping block 210 in close contact with both surfaces of the second fixing part 15.

In order to allow the first clamping block 110 and the second clamping block 210 to be slidable with respect to the first connection block 130 and the second connection block 230, respectively, A guide groove 225 having a trapezoidal shape is formed in each of the lower surface and the upper surface of the second connection block 230, and in the upper surface of the first clamping block 110 and the lower surface of the second clamping block 210. The guide protrusion 215 may be formed to correspond to the guide groove 225 and move along the inside of the guide groove 225 to protrude.

The first clamping block 110 and the second clamping block 210 have a plurality of

fastening holes

111 and 211 corresponding to the coupling holes 16 of the first fixing part 14 and the second fixing part 15. ) Is formed. The

fastening holes

111 and 211 are arranged at the same interval as the spacing of the coupling holes 16 (10 ° intervals in this embodiment). Therefore, a part of the plurality of coupling holes 16 formed in the first fixing part 14 and the second fixing part 15 and the bolts of the first clamping block 110 and the second clamping block 210. When the

bolts

112 and 212 are fastened through the

bolt fastening holes

111 and 211 and the coupling hole 16 in the state where the

fastening holes

111 and 211 are matched, the first fixing part 14 and the second fixing part ( 15 is fixedly coupled to the first clamping block 110 and the second clamping block 210, respectively.

The

bolts

112 and 212 when the first clamping block 110 and the second clamping block 210 apply a tensile force while fixing the first fixing portion 14 and the second fixing portion 15 of the test body 10. In order to prevent damage such as tearing of the edge of the coupling hole 16 of the test body 10 due to stress concentration, the first clamping block 110 and the second clamping block 210 are fixed to the first fixing part 14. And in order to further increase the coupling force between the second fixing portion 15, as shown in Figure 5 the first clamping block 110 and the second clamping block 210 on the inner surface of the first height The surface of the government 14 and the surface of the second fixing part 15 may be formed in the irregularities of the grid form 300 in close contact.

Although the first jig 100 and the second jig 200 may perform a shear test test by fixing the test body 10 in a normal temperature state, the first jig in order to evaluate the influence of temperature in a cryogenic state The 100 and the second jig 200 may be installed in a cryogenic chamber (not shown) into which liquid nitrogen is injected.

Referring to the method of performing a shear test using the shear test apparatus of the present invention configured as described above are as follows.

FIG. 6A illustrates a state in which a shear test is performed under a pure shear load condition, and the deformation part 12 of the test body 10 is in a horizontally laid state. The first fixing part 14 is coupled to the first clamping block 110 of the first jig 100, and the second fixing part 15 of the test body 10 is the second clamping block of the second jig 200. After coupling to the (210), by applying a load in a direction away from each other (upper direction and lower direction on the drawing) to the first jig 100 and the second jig 200 by means of tensile strain (deformation part of the test body 10 ( 12), the shear load is applied in the width direction, so the strain-based failure condition can be obtained under the pure shear load condition.

6B shows a state in which a shear test is performed under a tension-shear load condition, in which the deformed portion 12 of the test body 10 is laid obliquely at an angle of about 45 °. The first fixing part 14 of the test body 10 is coupled to the first clamping block 110 of the first jig 100 so as to be in a true state, and the second fixing part 15 of the test body 10 is connected to the second fixing part 15. After coupling to the second clamping block 210 of the jig 200, and then applying a tensile load in the vertical direction to the first jig 100 and the second jig 200 by the tension deformation means, the deformation part of the test body 10 Tensile and shear loads are simultaneously applied to (12) in the longitudinal and width directions, and a strain-based failure condition equation can be obtained under these load conditions.

FIG. 6C shows a state in which a shear test is performed under a tensile load condition, and the first height of the test body 10 is arranged such that the deformation part 12 of the test body 10 is disposed in the vertical direction of the top and bottom. Couple the government 14 to the first clamping block 110 of the first jig 100, the second fixing part 15 of the test body 10 to the second clamping block 210 of the second jig 200 When the tensile load is applied to the first jig 100 and the second jig 200 in the vertical direction by the tensile strain imparting means, the tensile load is applied to the deformation part 12 of the test body 10 in the longitudinal direction. Under these load conditions, the strain-based failure condition equation can be obtained.

As described above, according to the present invention, the angle of the test body 10 may be mounted on the first jig 100 and the second jig 200 of the shear test apparatus by changing the angle, and the test body 10 may be mounted on the shear test apparatus. Depending on the mounting angle, the orientation of the deformation part 12 of the test body 10 is changed, so that the load condition is changed. Therefore, the shear test can be performed by applying shear and / or tensile force under various load conditions.

In other words, according to the present invention, since the test body 10 of the metallic material has a specific shape as described above, the direction of the deformation part 12 is changed according to the angle at which the test body 10 is coupled to the jig of the shear test apparatus. The test can be carried out under different load conditions.

Meanwhile, in the above-described embodiment, the first clamping block 110 and the first holder block 120 constituting the first jig 100 are separated from each other, and the second jig 200 is similarly configured as the second clamping block. 210 and the second holder block 220 is configured to be separated.

However, as shown in another embodiment in FIG. 7, one clamping block 110a is integrally formed under one side of the first holder block 120, and the other clamping block 110b is formed in the first holder block. The two

clamping blocks

110a and 110b may be coupled to each other by a bolt 112 for fixing the test body 10 by being separated from the 120.

Since the second jig 200 may also be configured in the same structure, a detailed description thereof will be omitted.

In the above description, the technical idea of the present invention has been described with the accompanying drawings. However, the present invention has been described by way of example and is not intended to limit the present invention. In addition, it is apparent that any person having ordinary knowledge in the technical field to which the present invention belongs may make various modifications and imitations without departing from the scope of the technical idea of the present invention.

The present invention can be applied to test specimens and shear test apparatus for shear test of metal materials used in various industries.

Claims

A plurality of openings 11 are formed to penetrate at both sides of the central portion, and a deformation portion 12 is formed between the openings 11 to which shear or tensile force is applied, and from each opening 11 to the edge. It is provided with two separation holes 13 which are cut and extended, and the first fixing part 14 coupled to the first jig of the shear test apparatus and the second jig of the shear test apparatus based on the separation holes 13. Shear test specimen of a metal material, characterized in that consisting of the second fixing part (15) to be coupled.
According to claim 1, wherein the first fixing part (14) and the second fixing part (15) are made of a semi-circular plate, respectively, characterized in that the shear test specimen of the metal material, characterized in that the disk shape as a whole.
According to claim 1, wherein each of the first fixing part 14 and the second fixing part 15, a plurality of coupling holes 16 coupled to the first jig and the second jig, respectively, spaced along the circumferential direction Shear test specimen of metal material, characterized in that formed and placed.
The test piece for a shear test of a metal material according to claim 1, wherein the opening part (11) is oval.
The test piece for a shear test of a metal material according to claim 4, wherein the opening part (11) has a symmetrical shape with respect to the center point of the deformation part (12).
The test piece for a shear test of a metal material according to claim 1, wherein the two separation holes (13) are formed in the same line as the center of the deformation part (12).
An apparatus for shearing a test body according to any one of claims 1 to 6,

A first jig 100 to which the first fixing part 14 of the test piece is detachably coupled;

A second jig 200 disposed opposite to the first jig 100 and having a second fixing part 15 of the test body detachably coupled thereto;

Tensile strain applying means for pulling the first jig 100 and the second jig 200 away from each other;

Shear test apparatus of a metal material test body comprising a.
The method according to claim 7, wherein the plurality of coupling holes 16 are formed in the first fixing part 14 and the second fixing part 15 at intervals along the circumferential direction. At least one bolt fastening hole (111, 211) corresponding to the coupling hole 16 is formed in the jig 200, a part of the coupling hole 16 and the bolt fastening holes (111, 211) As the bolts 112 and 212 are fastened through the bolt fastening holes 111 and 211 and the coupling hole 16 in the matched state, the first fixing part 14 and the second fixing part 15 are connected to the first jig 100. And a second test jig of the metal material test piece, characterized in that coupled to the jig (200).
9. The shear test apparatus of claim 8, wherein the plurality of bolt fastening holes (111, 211) of the first jig (100) and the second jig (200) are arranged in an arc shape.
According to claim 8, The first jig 100, The first clamping block 110 is formed of two sets of bolt fastening holes (111, 211) is coupled to the first fixing portion 14 And a first holder block 120 connecting the two first clamping blocks 110 to each other, and a first connection block 130 connecting the first holder block 120 to the tensile strain applying means. ,

The second jig 200, the second clamping block 210 is formed of two sets of bolt fastening holes (111, 211) are coupled to the second fixing part 15 and the two second A metal comprising a second holder block 220 for connecting the two clamping block 210 and a second connection block 230 for connecting the second holder block 220 with the tensile strain imparting means. Shear test device of material test body.
The lattice of claim 10, wherein the grating is in close contact with the surface of the first fixing part 14 and the surface of the second fixing part 15 on the inner surfaces of the first clamping block 110 and the second clamping block 210. Shear test apparatus of the metal material test body, characterized in that the irregularities of the form 300 is formed.
According to claim 7, wherein the first jig (100) and the second jig (200) is a shear test specimen for a metal material, characterized in that it is installed in the cryogenic chamber in which the liquid nitrogen is injected.