Sampling structure of soft material biaxial tensile sample

Abstract

The utility model relates to a sampling structure of a soft material biaxial tensile sample, which comprises a base and a sampling knife vertically connected to the base, the sampling knife is of an open cavity structure, a blade is formed at the edge of the opening of the cavity structure, a hole pressing needle is arranged in the cavity structure of the sampling knife, the needle tip of the hole pressing needle faces the opening of the cavity structure, and the sampling knife is provided with a sampling hole. And the needle tail of the hole pressing needle is inserted and positioned with the surface of the base. According to the utility model, the tensile sample can be simply and efficiently obtained, the repeatability of a biaxial tensile test is improved, the efficiency of testers is improved, and the time cost is effectively saved.

Description

TECHNICAL FIELD

[0001] The utility model relates to sampling structure technical field, concretely relates to a sampling structure of soft material biaxial tensile test piece. BACKGROUND

[0002] The traditional soft material tensile test piece production method is cut by scissors or cutting props, but the method has certain requirements for the production personnel, and the test piece obtained by the method has low repeatability, and the accuracy and repeatability of the experiment cannot be satisfied.

[0003] The prior art sampling die has the following disadvantages: single function, fixed size, lack of knife seat to relieve blade impact, inconvenient to use. Although there is a uniaxial tensile sampling device, it can only be uniaxially stretched, and cannot meet the demand of biaxial tensile sampling. UTILITY MODEL CONTENT

[0004] In view of the deficiencies of the prior art, the utility model provides a sampling structure of soft material biaxial tensile test piece, which can obtain the tensile test piece simply and efficiently, improve the repeatability of the test, improve the efficiency of the tester, and save time cost.

[0005] The utility model is realized through the following technical schemes:

[0006] A sampling structure of soft material biaxial tensile test piece is provided, which comprises a base and a sampling knife connected vertically on the base, the sampling knife is a cavity structure with an open mouth, and a blade edge is formed on the open edge of the cavity structure, a pressure hole needle is arranged in the cavity structure of the sampling knife, the needle tip of the pressure hole needle faces the opening of the cavity structure, and the needle tail of the pressure hole needle is inserted and positioned with the surface of the base.

[0007] Further, the base is a ductile base.

[0008] The ductile base can be a plexiglass base or a wooden base, which can effectively relieve the impact of the sampling knife caused by the knocking of the heavy object, and avoid damage to the sampling test piece.

[0009] Further, the surface of the base is provided with a plug hole for inserting and fixing the pressure hole needle in the area opposite to the pressure hole needle.

[0010] The pressure hole needle is inserted into the surface of the base through the reserved plug hole, so that not only the stability of the pressure hole needle is maintained, but also the obtained test piece is not damaged at the needle hole.

[0011] Further, the height of the needle tip of the pressure hole needle is higher than the height of the blade edge.

[0012] The height of the hole-punching needle tip is slightly higher than the height of the blade, so as to facilitate hole-punching without damaging the table top.

[0013] Further, the sampling cutter is in a cross shape, integrally formed by two fixed parts perpendicularly intersecting each other, each fixed part comprising a tensile zone in a rectangular cross section and a clamping zone in a rectangular cross section symmetrically connected at both ends of the tensile zone, the rectangular cross section of the tensile zone having a length of b2 and a width of a2, the rectangular cross section of the clamping zone having a length of a1 and a width of b1, and The clamping zone and the tensile zone are connected by an arc segment.

[0014] The length of the clamping zone should be greater than that of the tensile zone, so as to prevent the tested sample from being damaged due to clamping of the testing machine before the test area, and therefore the length of the clamping zone should be greater; if the clamping zone is too much greater than the tensile zone, eccentricity during stretching may occur due to misalignment, which affects the experimental results, and therefore it is recommended that the reasonable value here be 2-10.

[0015] Further, the four corners of the tensile zone of the two fixed parts at the intersecting connection are connected by the same arc segment as that between the clamping zone and the tensile zone.

[0016] Further, the hole-punching needles are arranged at four ends of the cross-shaped cavity structure of the sampling cutter, and four hole-punching needles arranged in a straight line and parallel to the length direction of the tensile zone are perpendicularly inserted into each end.

[0017] Further, the arc segment is a circular arc segment, and the radius of the circular arc segment is (a1+a2) / 2.

[0018] If a straight angle is directly used instead of a circular arc for transition, stress concentration will occur at the corner, the test piece will be damaged, and the clamping zone cannot uniformly transmit force to the tensile zone, and therefore it is recommended that a circular arc with a radius of (a1+a2) / 2 be used for transition.

[0019] Further, the arc segment is an elliptical arc segment, and the major axis of the elliptical arc segment is a1 / 2 and the minor axis is a2.

[0020] The elliptical arc segment is a further optimization of the circular arc transition, and if a circular arc is used, the clamping zone or the tensile zone cannot be smoothly transitioned to the circular arc region, and therefore it is recommended that an elliptical transition be used, which can effectively prevent the non-uniformity of the tensile force transmitted from the clamping zone to the test area during stretching.

[0021] Further, the sampling cutter is in a quadrilateral shape, formed by four fixed plates perpendicularly connected in sequence.

[0022] The quadrilateral sampling cutter can directly cut the required biaxial tensile test sample, which is convenient for subsequent biaxial tensile test.

[0023] Further, the hole pressing needles are arranged in a ring shape at the center of the quadrilateral cavity structure of the sampling cutter, four groups of the hole pressing needles are arranged in a one-dimensional center symmetric distribution on the four sides of the quadrilateral cavity structure and keep a certain distance from the fixed plate, and the sample in the inner region of the ring-shaped arranged hole pressing needles is used for a test section.

[0024] The utility model discloses the beneficial effects of:

[0025] The utility model discloses two kinds of sampling structures for making biaxial tensile test piece of soft material (super-elastic material, composite material and biological soft tissue etc.), which can obtain more beautiful and complete biaxial tensile test test piece than traditional method without damaging the sample.

[0026] The sampling structure can shorten the preparation of the uniaxial tensile test, and the qualified rate of the sample is close to 100%, which can greatly improve the efficiency of the experimental tester, thereby improving the production and research efficiency of the enterprise and saving the cost. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is the bottom view of the utility model embodiment 1.

[0028] Figure 2 It is the front view of the utility model embodiment 1.

[0029] Figure 3 It is the perspective view of the utility model embodiment 1.

[0030] Figure 4 It is the bottom view of the utility model embodiment 2.

[0031] Figure 5 It is the front view of the utility model embodiment 2.

[0032] Figure 6 It is the perspective view of the utility model embodiment 2.

[0033] The drawings show:

[0034] 1, base, 2, sampling cutter, 3, stretching area, 4, clamping area, 5, fixed part, 6, hole pressing needle, 7, blade, 8, fixed plate, 9, arc segment. DETAILED DESCRIPTION

[0035] To clearly illustrate the technical features of the scheme, the following through specific implementation, the scheme is described.

[0036] Embodiment 1:

[0037] As Figures 1 to 3As shown in the figure, a sampling structure of a soft material biaxial tensile specimen includes a base 1 and a sampling knife 2 vertically connected to the base 1. The base 1 is a flexible base. In this embodiment, the flexible base is selected as a plexiglass base.

[0038] The sampling knife 2 is an open cavity structure, and a blade edge 7 is formed at the open edge of the cavity structure. The sampling knife 2 is provided with a pressure hole needle 6 in the cavity structure, the needle tip of the pressure hole needle 6 faces the opening of the cavity structure, and the surface of the base 1 opposite to the pressure hole needle 6 is provided with a plug hole for inserting and fixing the pressure hole needle 6, and the needle tail of the pressure hole needle 6 is inserted and positioned with the surface of the base 1.

[0039] In order to avoid damaging the desktop, the height of the needle tip of the pressure hole needle 6 is slightly higher than the height of the blade edge 7.

[0040] In this embodiment, the sampling knife 2 is cross-shaped and integrally formed by two fixed parts 5 vertically intersecting each other. Each fixed part 5 includes a tensile area 3 with a rectangular cross section and a clamping area 4 symmetrically connected to both ends of the tensile area 3 and also with a rectangular cross section, as shown in the figure. Figure 1 As shown in the figure, the length of the rectangular cross section of the tensile area 3 is b2, and the width is a2. The length of the rectangular cross section of the clamping area 4 is a1, and the width is b1, and In this embodiment, the width of the two ends is 5 times the width of the middle, and the length of the middle is 5 times the length of the two ends. The clamping area 3 and the tensile area 4 are transitionally connected by an arc segment 9.

[0041] The pressure hole needle 6 is arranged at four ends of the cross-shaped cavity structure of the sampling knife 2, and four pressure hole needles 6 arranged in a straight line and parallel to the length direction of the tensile area 3 are vertically inserted into each end. The four ends are provided with the pressure hole needle 6, which is convenient for clamping the specimen in the subsequent biaxial tensile test. The tensile areas 3 of the two fixed parts 5 are transitionally connected at the four corners of the intersection connection by the same arc segment 9 between the clamping area 4 and the tensile area 3.

[0042] As an embodiment of this embodiment, the arc segment 9 is a circular arc segment, and the radius of the circular arc segment is (a1+a2) / 2.

[0043] As another embodiment of this embodiment, the arc segment 9 is an elliptical arc segment, and the major axis of the elliptical arc segment is a1 / 2 and the minor axis is a2.

[0044] The working process of the sampling structure of this embodiment is as follows:

[0045] Lay the soft material sample to be tested on the test table or operation table, select a suitable test area on the soft material sample to be tested, place the sampling knife 2 of the sampling structure on the test area, and make the center area of the sampling knife 2 located directly above the sample material test area, at the same time, the pressing hole needles 6 in the four end portions of the sampling knife 2 are inserted into the sample material and clamp the sample material, then knock several times on the base 1 with a weight, cut the sample material by using the blade 7 of the sampling knife 2, and cut out a sample matching the cavity structure shape of the sampling knife 2, so as to obtain the required biaxial tensile test piece.

[0046] Embodiment 2:

[0047] As Figure 4 As Figure 6 As shown in the drawings, a sampling structure of a soft material biaxial tensile test sample includes a base 1 and a sampling knife 2 vertically connected to the base 1, and the base 1 is a flexible base. In this embodiment, the flexible base is a wooden base. The shape of the base 1 is not limited and can be one of a rectangle, a triangle and a circle.

[0048] The sampling knife 2 is an open cavity structure, and a blade 7 is formed on the open edge of the cavity structure. In this embodiment, the sampling knife 2 is a quadrilateral formed by four fixed plates 8 connected vertically in sequence. The blade 7 is arranged on the open edge of the four fixed plates 8, and the blade 7 and the pressing hole needles 6 are made of metal or ceramic materials which can form sharp blades.

[0049] The pressing hole needles 6 are arranged in a ring shape in the center of the quadrangular cavity structure of the sampling knife 2. There are four groups of the pressing hole needles 6, which are arranged in a one-dimensional central symmetric manner on the four sides of the quadrangular cavity structure and are spaced apart from the fixed plates 8. There are 16 pressing hole needles 6 arranged in a ring shape, and there are 4 pressing hole needles 6 in each group. The inner region of the pressing hole needles 6 arranged in a ring shape is used for a test section. The needle tip of the pressing hole needle 6 faces the opening of the cavity structure, and the surface of the base 1 opposite to the pressing hole needle 6 is provided with a plug hole for inserting and fixing the pressing hole needle 6. The needle tail of the pressing hole needle 6 is inserted and positioned on the surface of the base 1 to avoid affecting the obtained test piece at the needle hole. After insertion, the pressing hole needle 6 can be fixed by welding technology.

[0050] In order to avoid damaging the desktop, the height of the needle tip of the pressing hole needle 6 is slightly higher than the height of the blade 7.

[0051] The specific size of the pressing hole needle 6 and the distance between the pressing hole needle 6 and the inner wall of the blade are selected according to the specific requirements of the experiment. In the utility model, the ratio of the height of the blade tip to the overall height of the blade 7 can be changed according to the experimental requirements when obtaining the tensile test piece.

[0052] For different sizes of the sample to be tested, different sizes of the sampling structure need to be made according to requirements. In order not to lose generality, the utility model claims to protect all sizes of the sampling structure of the same type.

[0053] The working process of the sampling structure of the embodiment is as follows:

[0054] The soft material sample to be tested is laid on a test table or an operation table, a suitable test area is selected on the soft material sample to be tested, the sampling knife 2 of the sampling structure is placed on the test area, and the center area of the sampling knife 2 is located directly above the sample material test area, at the same time, the annularly arranged pressing hole needles 6 in the cavity structure of the sampling knife 2 are inserted into the sample material and clamp the sample material, the inner area of the annularly arranged pressing hole needles 6 is the test section of the sample, which is not damaged by the pressing hole needles 6, the sample material is cut by the blade 7 of the sampling knife 2 by knocking several times on the base 1 with a weight, and a sample matching the shape of the cavity structure of the sampling knife 2 is cut, so that the required biaxial tensile test piece is obtained, and the sample in the inner area of the annularly arranged pressing hole needles 6 is used as the test section for biaxial tensile test.

[0055] Of course, the above description is not limited to the above examples, and the technical features not described in the utility model can be realized by or using the prior art, which will not be described here; the above embodiments and drawings are only used to illustrate the technical scheme of the utility model and are not a limitation on the utility model, the utility model is described in detail with reference to the preferred embodiments, and those skilled in the art should understand that the changes, modifications, additions or replacements made by those skilled in the art within the essential scope of the utility model do not deviate from the purpose of the utility model, and should also belong to the protection scope of the claims of the utility model.

Claims

1. A sampling structure for biaxial tensile testing of soft material samples, comprising a base and a sampling knife connected perpendicularly to the base, characterized in that: The sampling knife is an open cavity structure, and a blade is formed at the open edge of the cavity structure. The sampling knife is provided with a pressure hole needle in the cavity structure. The needle tip of the pressure hole needle faces the opening of the cavity structure, and the needle tail of the pressure hole needle is inserted and positioned with the base surface.

2. The sampling structure of a soft material biaxially-stretched specimen according to claim 1, characterized in that: The area of the base surface opposite to the pressure hole needle is provided with a pre-formed insertion hole for inserting and fixing the pressure hole needle.

3. The sampling structure of a soft material biaxially-stretched specimen according to claim 1, characterized in that: The height of the needle tip of the pressure hole needle is higher than the height of the blade.

4. The sampling structure of a soft material biaxially-stretched specimen according to claim 1, characterized in that: The sampling knife is cross-shaped, integrally formed by two fixed parts perpendicularly intersecting each other, each fixed part comprises a tensile area with a rectangular cross section and clamping areas with a rectangular cross section symmetrically connected at both ends of the tensile area, the rectangular cross section of the tensile area has a length of b2 and a width of a2, the rectangular cross section of the clamping area has a length of a1 and a width of b1, and The clamping area and the tensile area are connected through an arc segment.

5. The sampling structure of a soft material biaxially-stretched specimen according to claim 4, characterized in that: The four corners of the intersection connection of the stretching area of the two fixing parts are connected by the same arc segment between the clamping area and the stretching area.

6. The sampling structure of a soft material biaxially-stretched specimen according to claim 4, characterized in that: The pressure hole needles are arranged at the four ends of the cross-shaped cavity structure of the sampling knife, and four pressure hole needles arranged in a straight line and parallel to the length direction of the stretching area are vertically inserted at each end.

7. The sampling structure of a soft material biaxially-stretched specimen according to claim 4 or 5, characterized in that: The arc segment is a circular arc segment, and the radius of the circular arc segment is (a1+a2) / 2.

8. The sampling structure of a soft material biaxially-stretched specimen according to claim 4 or 5, characterized in that: The arc segment is an elliptical arc segment, and the major axis of the elliptical arc segment is a1 / 2 and the minor axis is a2.

9. The sampling structure of a soft material biaxially-stretched specimen according to claim 1, characterized in that: The sampling knife is a quadrilateral formed by four fixing plates connected vertically in sequence.

10. The sampling structure of a biaxially stretched specimen of a soft material according to claim 9, characterized in that: The pressure hole needles are arranged in a ring at the center of the quadrilateral cavity structure of the sampling knife. There are four groups of pressure hole needles, which are distributed in a straight line and symmetrically at the four sides of the quadrilateral cavity structure and keep a certain distance from the fixing plates. The sample in the internal area of the ring-shaped pressure hole needle is used for the test section.

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