JPH0633053U - Mounting device for tensile test of specimen - Google Patents

Abstract

(57) [Summary] [Purpose] To allow a load to be applied uniformly without causing bending or twisting of the sample piece. [Structure] A hole 6 is formed in a fixture 2 fixed to both ends of a sample piece 1. The latch provided on the side of the tensile tester is composed of protrusions 7 and 8 having a smaller diameter than that inserted into the hole 6 in order to latch the fixture 2.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a mounting device for a tensile test of a thin sample piece such as a film.

[0002]

[Prior art]

 Conventionally, when measuring the elastic coefficient of a coating film (for example, a magnetic layer) on a base film of a magnetic recording medium or the like, a load-displacement characteristic (stress -The strain coefficient) is measured to obtain the elastic coefficient, and the elastic coefficient of the coating film is calculated by calculation from the elastic coefficient of the base film alone and the elastic coefficient of the base film with the coating film.

Here, in the case of measuring the load-displacement characteristic of a base film alone or a base film with a coating film, conventionally, both ends of a sample piece are directly attached and fixed to a test apparatus body by a chucking method or a screwing method. Was.

[0004]

[Problems to be solved by the device]

 However, in the past, there was a problem that the sample piece was bent or twisted to the extent that the sample piece was always attached, and the load was not applied uniformly. In particular, when measuring the elastic modulus of the coating film for the final purpose, it is necessary to accurately apply a small load to the sample piece and to accurately measure the displacement of about 10 μm at that time. Due to slight bending or twisting caused by bending of the sample piece, the load is not evenly applied to the sample piece, which causes measurement error.

In view of such circumstances, an object of the present invention is to provide a mounting device for a tensile test of a sample piece, which can apply a load uniformly without causing bending or twisting of the sample piece. .

[0006]

[Means for Solving the Problems] Therefore, according to the present invention, there are provided a fixture that is fixed to both ends of a sample piece, and a latch that is provided on the side of the tensile test device and that latches each fixture. From this, an attachment device for tensile test of sample pieces is constructed. Then, a hole is formed in one of the fixing tool and the hooking tool, and a protrusion having a smaller diameter than that inserted into the hole is formed in the other and the hole and the protrusion make The structure is such that the fixture is hooked on the hook.

[0007]

[Action]

 In the above structure, the fixture with holes is fixed to the sample piece, and the fixture with protrusions on the tensile tester side is used, or the fixture with protrusions is fixed to the sample piece and pulled. Hook the hook with a hole on the test equipment side, and the hole and the protrusion with a diameter smaller than this will lock the fixture with the hook, so there will be a gap between the hole and a protrusion with a diameter smaller than this. It can be moved freely with, and even if bending occurs during mounting, it will move so that a uniform load is applied to the sample piece during the tensile test.

[0008]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. Referring to FIG. 1, a fixture 2 fixed to both ends of a sample piece 1 comprises a fixture body 3 and a holding plate 5 fixed to the fixture body 3 with a screw 4, and the sample piece is interposed between them. The end of 1 is clamped. A hole 6 is formed in the fixture body 3.

The latch provided on the tensile tester side is composed of protrusions 7 and 8 having a smaller diameter than that inserted into the hole 6 in order to latch the fixture 2. That is, the structure is such that the fixing tool 2 is hooked by the hole 6 and the projections 7 and 8 having a smaller diameter. Here, as shown in Fig. 2 (a), when the sample piece 1 is obliquely set in the tensile tester, the fixture 2 is rotated by applying a vertical load as shown in (b). The load is evenly applied to the sample piece 1.

Further, as shown in FIG. 3 (a), even when the attachment of the sample piece 1 to the fixture 2 is bent, the fixture 2 is rotated as shown in FIG. The load will be evenly applied. Next, an example including a tensile test device will be described. Referring to FIG. 4, in the sample piece 1, the fixture 2 on the upper end side is hooked on the hook (projection) 7 provided on the fixed body 11 and hung down.

Further, the fixture 2 on the lower end side of the sample piece 1 is hooked on a hook (projection) 8 provided at one end of the balance 12. The balance 12 is provided on a fulcrum 13 such as a knife edge, and one end thereof is connected to the lower end side of the sample piece 1 as described above. It is possible to suspend weights at both ends of the balance 12, and at the time of measurement, the weight 14 is suspended at one end (connection side with the sample piece 1) (see FIG. 5). Further, a reflecting mirror 15 is erected on the fulcrum of the balance 12 so as to rotate integrally with the balance 12. With this structure, the balance 12 is always erected in the same stress-free state without receiving a load during measurement.

The laser light irradiating device 16 irradiates the laser light toward the reflecting mirror 15 from a fixed position. Further, a reflection light detection device 17 which is capable of scanning in the vertical direction and detects the position of the reflection light from the reflection mirror 15 is provided (see FIG. 5). If the horizontal distance L ₁ from the fulcrum 13 of the balance 12 to the sample piece 1 is, for example, 0.05 m, the horizontal distance L ₂ from the fulcrum 13 of the balance 12 to the laser light irradiation device 16 and the reflected light detection device 17 is, for example, 10m Further, in the state where the weight 14 is not attached, it is assumed that the laser light irradiated in the horizontal direction enters the reflecting mirror 15 at a right angle and is reflected at a right angle, and the incident light and the reflected light are on the same path.

When measuring the load-displacement characteristic, one end of the balance 12 is connected to the lower end side of the sample piece 1 and then a known weight 14 is applied to one end of the balance 12 to apply a load to the sample piece 1. It As a result, the sample piece 1 is stretched, and the balance 12 is rotated by an angle θ by an amount commensurate with the displacement λ, and accordingly, the reflecting mirror 15 is also rotated by an angle θ.

Then, the reflected light from the reflecting mirror 15 is rotated by an angle 2θ with respect to the incident light, and its position is detected by the reflected light detection device 17, so that the angle θ can be calculated. In this case, the reflected light detection device 17 is moved up and down to find the angle at the position where the amount of received light is maximum. Therefore, the displacement λ of the sample piece 1 can be obtained as λ = L ₁ tan θ.

When the load P-displacement λ characteristic is measured, the stress σ = P / A is obtained from the original cross-sectional area A of the sample piece 1, and the strain ε = λ / L is obtained from the original length L of the sample piece 1. Thus, the stress σ-strain ε characteristic is obtained, and the elastic coefficient E = σ / ε of the sample piece 1 can be obtained from these. When obtaining the elastic modulus of the coating film on the base film, first, using the base film alone and the coated base film as sample pieces, the respective elastic coefficients are determined by the above method.

Here, referring to FIG. 6, where T _{B is} the thickness of the base film, T _{C is} the thickness of the coating film, E _{B is} the elastic coefficient of the base film, and E _C is the elastic coefficient of the coating film. The elastic coefficient E _T of the base film with a coating film can be expressed by the following equation (1). E _T = (T _B E _B + T _C E _C ) / (T _B + T _C ) (1) By solving this formula (1) for E _C , the following formula (2) is obtained.

[0017] E _C = _{[(T B + T C) E} T -T B E B ] / T _C ··· (2) Therefore, the elastic coefficient of the base modulus of the film alone E _B and the film-coated base film By obtaining E _T , the elastic modulus E _C of the coating film can be calculated from these, the thickness T _B of the base film, and the thickness T _{C of} the coating film from the equation (2). In the above embodiment, the hole 6 is formed on the side of the fixture 2 and the hooks are formed on the protrusions 7 and 8. However, conversely, the protrusions are formed on the side of the fixture and the hooks are formed. You may make it form a hole in the side.

[0018]

[Effect of device]

 As described above, according to the present invention, a uniform load is applied to the sample piece, and the measurement accuracy is improved. Moreover, since it is not necessary to worry about the bending force applied to the sample piece at the time of mounting, the measurement can be performed with one mounting and the handling becomes easy.

[Brief description of drawings]

FIG. 1 is a front view and a side view of a fixture and the like showing an embodiment of the present invention.

FIG. 2 is a diagram showing a first example of movement.

FIG. 3 is a diagram showing a second example of movement.

FIG. 4 is a schematic view showing a state of the tensile test device before measurement.

FIG. 5 is a schematic view showing a state during measurement of the tensile test device.

FIG. 6 is a sectional view of a base film with a coating film.

[Explanation of symbols]

 1 sample piece 2 fixing tool 3 fixing tool body 4 screw 5 clamping plate 6 hole 7, 8 latch (projection) 11 fixed body 12 balance 13 fulcrum 14 weight 15 reflector 16 laser light irradiation device 17 reflected light detection device

Claims (1)

[Scope of utility model registration request] 1. An attachment device for a tensile test of a sample piece, comprising a fixing tool which is fixed to both ends of the sample piece, and a hooking tool which is provided on the side of the tensile test apparatus and hooks each fixing tool. A hole is formed in one of the fixing tool and the hooking tool, and a protrusion having a smaller diameter than that inserted into the hole is formed in the other, and the fixing is performed by the hole and the protrusion. An attachment device for a tensile test of a sample piece, characterized in that a tool is hooked on the hooking tool.