JP2017111024A - Test piece, test device, measurement device, analysis device, analysis method, and analysis program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable continuous or discontinuous measurement of material properties at low cost.SOLUTION: A test piece comprises a fixing section 3A provided on each end of a rectangular plate-like substrate 4 in a longitudinal direction and designed to be fixed to a tester, and a measurement section 3B provided in a middle part of the substrate 4 in the longitudinal direction and formed into a point-symmetrical shape that is symmetrical about a point of symmetry 5 that coincides with center points of the substrate 4 in the longitudinal and width directions. The measurement section 3B has two holes 7, each being formed through the substrate 4 such that a center point 7c thereof lies on a circle 6 centered around the point of symmetry 5, and two slits 8 that cut through the substrate 4 from both ends 4e thereof in the width direction to reach respective holes 7.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a test piece, a test apparatus, and a material characteristic value measurement method for acquiring a material characteristic value, and an analysis apparatus, an analysis method, and an analysis program using the acquired material characteristic value.

  Conventionally, at the design and development stage of an industrial product, the product is modeled and the strength, stress distribution, deformation mode, and the like are simulated by CAE analysis, thereby improving the efficiency of design examination. In CAE analysis, a finite element method (FEM) or the like is generally used, and a product model created based on CAD data is divided into a plurality of meshes, and material characteristics and various conditions (loads) are applied to each mesh. Conditions, constraint conditions, etc.) are given as input values. In addition, as a prediction system for simulating breakage when a part is deformed by an external force or forced deformation by using the finite element method, there is a system described in Patent Document 1, for example.

JP 2014-199529 A

  By the way, GISSMO (Generalized Incremental Stress-State Dependent Damage Model) is known as one of the methods (models) for solving the material damage (damage, destruction) problem. That is, this is a technique for expressing breakage by setting a breakage strain for each triaxial degree of stress representing the direction and state of the stress. Stress triaxiality is a parameter defined by the ratio of hydrostatic stress to Mises stress. It is 0 for shear, 1/3 for uniaxial tension, and 2/3 for biaxial tension. According to this model, it is possible to take into account the change in breakage strain due to the stress state.

  However, in order to use this model, it is necessary to obtain in advance the relationship between the stress triaxiality and the breakage strain. Therefore, it is necessary to prepare a test apparatus (tester and test piece) that can measure the fracture strain in each stress state. However, since the test apparatuses for measuring the breaking strains of shear, uniaxial tension, and biaxial tension are different from each other, there is a problem that the cost of the test becomes high.

  Moreover, even if the breakage strain in each stress state can be measured by a separate test apparatus, the data (breakage strain) obtained thereby is only a value in each stress state. Therefore, in an intermediate state between the stress states (for example, a state in which both shearing and uniaxial tension are applied), an accurate value of failure strain cannot be used. When an object actually deforms, it is considered that various stresses are acting on the object. For this reason, if the stress state can be changed continuously or intermittently following the shape change of the object and the damage strain corresponding to this stress state can be used, the stress distribution, deformation mode, etc. can be simulated with high accuracy. It becomes possible. In addition, if material characteristic values (for example, elongation, deformation after fracture, drawing, etc.) other than breakage strains can be obtained for each triaxial stress, a simulation using these values can also be performed.

  This case has been devised in view of such problems, and a test piece, a test apparatus, a measurement method, and an analysis apparatus, which can measure and acquire continuous or intermittent material property values at low cost, An object is to provide an analysis method and an analysis program. The present invention is not limited to this purpose, and is a function and effect derived from each configuration shown in the embodiment for carrying out the invention described later, and has another function and effect that cannot be obtained by conventional techniques. is there.

  (1) The test pieces disclosed herein are provided at both ends in the longitudinal direction of a rectangular flat base material, and are provided at a fixing portion fixed to a testing machine, and at a middle portion in the longitudinal direction of the base material. And a measurement part formed in a point-symmetric shape with respect to both center points in the longitudinal direction and the width direction of the material, and the measurement part is drilled in the base material and centered on the symmetry point Having two holes in which each center point is arranged on the circumference, and slits notched from both edges in the width direction of the base material and reaching each of the two holes. It is a feature.

(2) The slit may be disposed within a range sandwiched between two perpendiculars extending from each of both edge ends in the longitudinal direction of the hole to the edge in the width direction of the base material. preferable.
(3) It is preferable that the said slit is extended in the orthogonal direction with respect to the edge part of the width direction of the said base material.

(4) A test apparatus disclosed herein includes a uniaxial tensile tester or a high-speed tensile tester as the tester, and the plurality of test pieces according to any one of (1) to (3) above. The plurality of test pieces are characterized in that the positions of the two holes are different from each other.
(5) The measurement method disclosed herein uses the test apparatus described in (4) above, and performs the tensile test by fixing the fixing portion of each test piece to the test machine. The characteristic value of the symmetrical point in the piece is measured.

  (6) The analysis device disclosed herein has a stress distribution or a deformation mode when a load is applied to an object made of the same material as the test piece according to any one of (1) to (3). An analysis apparatus for simulating by CAE analysis, using at least input values including shape data and material property data of the object, a CPU for executing the CAE analysis, and outputting an analysis result of the CAE analysis by the CPU And the material property data includes the property value measured by the measurement method described in (5) above.

  (7) The analysis method disclosed here uses, as input values, at least shape data and material property data of an object made of the same material as the test piece according to any one of (1) to (3) above. An analysis method for causing a computer to execute a process of simulating a stress distribution or a deformation mode when a load is applied to the object by CAE analysis, a model creation step for creating an analysis model of the CAE analysis, and the CAE analysis A condition setting step for setting the conditions of the above, and an analysis step for executing the CAE analysis using the analysis model and the conditions. The material property data includes the measurement according to (5) above The characteristic value measured by the method is included.

  (8) The analysis program disclosed here uses, as input values, at least shape data and material property data of an object made of the same material as the test piece according to any one of (1) to (3) above. An analysis program for causing a computer to execute processing for simulating stress distribution or deformation mode when a load is applied to the object by CAE analysis, a model creation step for creating an analysis model of the CAE analysis, and the CAE analysis A condition setting step for setting the conditions of the above, and an analysis step for executing the CAE analysis using the analysis model and the conditions. The material property data includes the measurement according to (5) above The characteristic value measured by the method is included.

  Continuous and intermittent material property values can be measured and acquired at low cost.

1 is a schematic perspective view showing a test apparatus according to an embodiment. It is a front view of the test piece used for the test apparatus of FIG. It is the figure which expanded the measurement part of the test piece of FIG. (A)-(f) is a figure which shows the change of the stress triaxiality when performing the CAE analysis by changing the shape of a test piece intermittently. It is the figure which expanded the measurement part of the test piece, (a) is a shear, (b) is uniaxial tension, (c) shows the shape corresponding to the stress state of biaxial tension. It is an example of a graph when the damage strain with respect to the stress triaxiality is measured. It is a flowchart which illustrates the procedure of the measuring method which concerns on embodiment. It is a block diagram which shows the analyzer which concerns on embodiment. It is a flowchart which illustrates the procedure of the analysis method which concerns on embodiment.

  With reference to the drawings, a test piece, a test apparatus, a measurement method using the test apparatus, and an analysis apparatus, an analysis method, and an analysis program using the measurement result will be described. Each embodiment shown below is only an example, and there is no intention of excluding various modifications and application of technology that are not clearly shown in each of the following embodiments. Each configuration of the present embodiment can be implemented with various modifications without departing from the spirit thereof. Further, they can be selected as necessary, or can be appropriately combined.

  The test apparatus according to the present embodiment performs a tensile test on each of a plurality of test pieces that are formed of a predetermined material and whose shape is changed. Data obtained by this test apparatus is used as an input value for simulating stress distribution and deformation mode when an external force is applied to a part molded with the material, for example, in the subsequent CAE analysis. That is, the test by this test apparatus is a pre-process that is performed prior to the CAE analysis that is the main process, and is performed to improve the accuracy of the CAE analysis.

[1. Test equipment]
FIG. 1 is a schematic perspective view of a test apparatus 1 according to the present embodiment. The test apparatus 1 includes a uniaxial tensile tester (hereinafter referred to as “tester 2”) and a test piece 3. The testing machine 2 has a load cell 2B fixed to the head portion 2A, and an upper chuck 2C connected to the load meter 2B. A lower chuck 2E is fixed to the pedestal 2D of the testing machine 2. The upper and lower ends of the test piece 3 are sandwiched between upper and lower chucks 2C and 2E. The head portion 2A moves up and down with respect to the frame body 2F, for example, by a motor (not shown). Thereby, the test piece 3 is extended at a constant speed. The elongation of the test piece 3 is detected by, for example, a displacement meter 2G directly attached to the test piece 3, and transmitted to the computer 2H.

  In this test apparatus 1, a plurality of test pieces 3 are prepared in advance, and each test piece 3 is set in the testing machine 2 to perform a tensile test. The plurality of test pieces 3 are formed so that their shapes are different from each other and the shapes change intermittently. Each of the plurality of test pieces 3 has a shape in which the stress triaxiality at the center point (load center) where the longitudinal center line and the width center line intersect changes intermittently. Here, the stress triaxiality is a value representing the direction and state of the stress, and is defined by the ratio of the hydrostatic stress to the Mises stress.

  The test apparatus 1 according to the present embodiment uses such a plurality of test pieces 3, so that the material characteristic values (load, elongation) when a uniaxial (uniaxial) tensile force acts while using the test machine 2 are used. , Deformation after rupture, squeezing, breakage strain, etc.), as well as material characteristic values when shearing force, biaxial tensile force, or force in which these are mixed are applied. In addition, if it replaces with the testing machine 2 and a high-speed tensile testing machine is used, the material characteristic (dynamic damage) when the test piece 3 will be stretched vigorously can be acquired. Hereinafter, the shape of the test piece 3 will be specifically described.

[2. Test pieces]
FIG. 2 is a front view illustrating one of the plurality of test pieces 3. As shown in FIG. 2, the test piece 3 of the present embodiment includes a fixed portion 3 </ b> A provided at both longitudinal ends of a rectangular flat substrate 4 and a measuring portion 3 </ b> B provided at a middle portion in the longitudinal direction. Prepare. The base material 4 is a rectangular flat plate having a uniform cross-sectional shape orthogonal to the longitudinal direction, and the material thereof has material characteristics to be acquired.

The two fixing portions 3 </ b> A are portions that are fixed to the upper and lower chucks 2 </ b> C and 2 </ b> E of the testing machine 2. On the other hand, the measurement part 3B is located between the two fixing parts 3A, and is a part that is deformed during the test and its elongation is measured. Measuring portion 3B is formed in point symmetry shape the center point 5 and the center line C _L of the widthwise center line C _W and the longitudinal direction of the substrate 4 intersects a point of symmetry. Hereinafter, both the center points 5 in the longitudinal direction and the width direction of the substrate 4 are referred to as “symmetry points 5”.

  The measurement unit 3 </ b> B includes two hole portions 7 formed in the base material 4 and slits 8 formed by cutting out from both edge portions 4 e on both sides in the width direction of the base material 4. As shown in FIG. 3, the hole 7 is arranged on a circumference 6 having a center radius 7 c with a predetermined radius centered on the symmetry point 5. Since the two hole portions 7 are arranged point-symmetrically with respect to the symmetry point 5, the straight line connecting both the center points 7 c and 7 c of the hole portion 7 passes through the symmetry point 5. The hole diameter φD of the hole portion 7 is set to a dimension smaller than the diameter of the circumference 6.

  The slit 8 is formed so as to penetrate the base material 4 in the thickness direction, and is provided continuously from the edge 4 e of the base material 4 to the hole 7 and continuing to the hole 7. When the measuring unit 3B is stretched by the testing machine 2, a portion where the hole 7 and the slit 8 are not formed is stretched. That is, as indicated by the dashed arrow in FIG. 2, the tensile force acts on the route F that avoids the hole 7 and the slit 8 and extends in the measurement unit 3B. Thereby, the symmetrical point 5 located in the center between the two hole parts 7 and 7 becomes a load center.

  The test piece 3 of this embodiment controls the stress triaxiality at the load center (symmetry point 5) by adjusting the position of the hole 7 (position of the center point 7c). When the test piece 3 is actually processed, the hole diameter φD of the hole 7, the minimum distance W1 between the two holes 7 and 7, and the maximum distance W2 from the edge 4e to the hole 7 are set. Managed. In addition, the slit 8 is for making the route F through which the tensile force passes, and if it is extended from each of the two hole parts 7 to the near one of the two edge parts 4e located on both sides. Well, the position in the longitudinal direction of the test piece 3 and the width dimension L2 are not particularly limited. However, in consideration of workability, the slit 8 is formed from the edge 7b, 7b in the longitudinal direction of the base material 4 in the hole 7 from each edge of the base material 4 as shown by a two-dot chain line in FIG. It is preferable to arrange within a range R sandwiched between two perpendiculars extending to the portion 4e. In the test piece 3 shown in FIGS. 2 and 3, the slits 8 are extended from the edge 7 b of each hole 7 on the fixing part 3 </ b> A side in the direction orthogonal to the edge 4 e of the base material 4.

The plurality of test pieces 3 are provided so that the positions of the hole portions 7 are different from each other. Specifically, a plurality of test strips 3, the center point 7c of the hole 7 is provided so as to be located within a range of 90 degrees from the widthwise center line C _W to the longitudinal center line C _L . That is, the test piece 3 in which the two hole portions 7 are both located on the width direction center line C _W and the test piece 3 in which the two hole portions 7 are both located on the longitudinal direction center line C _L are formed. At the same time, a plurality of test pieces 3 are formed in which the two hole portions 7 are shifted by a predetermined angle with respect to the center line _{CW in the} width direction. In addition, by reducing the interval of the predetermined angle in the plurality of test pieces 3, the number of data that can be acquired by the test increases, and it becomes possible to acquire data that is more continuous. Therefore, the predetermined angle is preferably set in consideration of the number of data to be acquired, the test cost, and the like.

4A to 4F are enlarged views of the measurement portion 3B of the test piece 3 in which the two hole portions 7 are sequentially rotated. The pattern in the figure shows the distribution of the stress triaxiality σ _TR obtained by performing the CAE analysis on each test piece 3. The stress triaxiality σ _{TR at} the symmetry point 5 is 0 in the test piece 3 in FIG. 4A, 1/3 in the test piece 3 in FIG. 4C, and in the test piece 3 in FIG. It can be read that it becomes 2/3. Also, the stress triaxiality σ _{TR at} the symmetry point 5 of the test piece 3 in FIG. 4B is a value larger than 0 and smaller than 1/3, and each test piece in FIGS. It can be read that the stress triaxiality σ _{TR at} the symmetry point 5 of 3 is a value larger than 1/3 and smaller than 2/3. That is, as shown in FIGS. 4A to 4F, the stress triaxiality σ _TR is intermittently changed from 0 to 2/3 by intermittently changing the two holes 7 along the circumference 6. Can be changed.

According to this result, when it is desired to obtain the material characteristic value when the shearing force is applied, the test piece 3 having the shape having the hole 7 shown in FIG. That is, as shown in FIG. 5A, the two holes 7 may be arranged side by side on the width direction center line C _W and the slits 8 connected to the holes 7 may be formed. The position and width dimension L2 of the slit 8 may be those shown in FIG. 4A or may be those shown in FIG.

Similarly, when it is desired to obtain the material characteristic value when each of the uniaxial tensile force and the biaxial tensile force is applied, the test piece having the shape of the hole 7 shown in FIGS. 3 may be created. That is, in the case of uniaxial tension, as shown in FIG. 5 (b), the holes 7 are arranged at positions shifted by 45 degrees with respect to the center line C _{W in the} width direction, and slits connected to the holes 7. 8 may be formed. In the case of biaxial tension, as shown in FIG. 5 (c), together with arranging a hole 7 at a position on the longitudinal center line C _L, by forming the slits 8 which leads to the holes 7 Good.

  In addition, when it is desired to obtain a material characteristic value when a stress obtained by mixing a shearing force and a uniaxial tensile force is applied, the position of the hole 7 shown in FIG. 5A and the hole shown in FIG. What is necessary is just to form the test piece 3 [For example, the test piece 3 as shown in FIG.4 (b)] of the shape which has arrange | positioned the hole 7 in the middle with the position of the part 7. FIG. Similarly, when it is desired to obtain a material characteristic value when a stress in which a uniaxial tensile force and a biaxial tensile force are mixed is applied, the position of the hole 7 shown in FIG. 5B and FIG. What is necessary is just to form the test piece 3 [For example, the test piece 3 as shown to FIG.4 (d), (e)] of the shape which has arrange | positioned the hole 7 in the middle of the position of the hole 7 shown in FIG.

[3. Measuring method]
The procedure of the measurement method using the test apparatus 1 described above is illustrated in FIG. First, a plurality of test pieces 3 having different shapes as described above are prepared by molding with a material having a material characteristic value desired to be acquired (step S1). Next, a tensile test is performed by fixing the fixing portion 3 </ b> A of each test piece 3 to the testing machine 2. This is repeated for the number of test pieces 3 (step S2). Thereby, the material characteristic values (load, elongation, deformation after fracture, drawing, breakage strain, etc.) at the symmetry point 5 of all the test pieces 3 are measured.

Based on these measurement results, for example, a continuous graph showing the failure strain ε _FA with respect to the stress triaxiality σ _TR as shown in FIG. 6 is created and stored in the memory or storage medium of the computer 2H. (Step S3). Incidentally, the strain breakage resulting in actual testing epsilon _FA is an intermittent value, it is possible to create a continuous graph by interpolating the discrete points (values of breakage strain epsilon _FA). The results and graphs (hereinafter referred to as “material property data”) are used in the CAE analysis described below.
In addition, the above-described plurality of test pieces 3 are molded, and each test piece 3 is fixed to a high-speed tensile tester and a tensile test is performed, whereby dynamic breakage is measured as a characteristic value at the symmetry point 5 of the test piece 3. Similarly, if it is stored as material property data, it can be used for CAE analysis of a collision test.

[4. Analysis device, analysis method]
The analysis apparatus and analysis method according to the present embodiment are an apparatus and method for simulating a stress distribution and a deformation mode when a load (stress) is applied to an object using CAE analysis software. In the analysis apparatus and the analysis method, material characteristic data of an object to be simulated is acquired in advance by the measurement method described above, and the material characteristic data is used as one of input values.

  The analysis apparatus according to the present embodiment is realized by a general-purpose computer that can execute a computer program 17 (analysis program) for CAE analysis. FIG. 8 is a schematic configuration diagram in the case where an analysis apparatus is configured using the computer 10. The computer 10 (analyzer) includes a CPU 11 (Central Processing Unit), a memory 12 [Read Only Memory (ROM), Random Access Memory (RAM), etc.], an external storage device 13 [Hard Disk Drive (HDD), Solid State Drive ( SSD, optical drive, etc.], input device 14 (keyboard, mouse, etc.), output device 15 (display, printer device, etc.) and communication device 16 (wireless or wired transmission / reception device). These are connected to be communicable with each other via a bus 18 (control bus, data bus, etc.) provided in the computer 10. The computer program 17 is installed in the external storage device 13.

  The computer program 17 may be recorded in a recording medium 19 that can be read by an optical drive, a flash memory, a reader / writer, or the like. Alternatively, the computer program 17 may be recorded in an online storage on a network to which the computer 10 can be connected. In any case, it can be executed by downloading the computer program 17 to the HDD, SSD or the like of the computer 10 or by reading it into the CPU 11 or the memory 12.

  The CPU 11 of this embodiment reads a program installed in the external storage device 13 on the memory 12 and executes it, and outputs a calculation result to the output device 15. Examples of the analysis model include vehicle parts (objects constituting the vehicle) such as a body, a bumper, and a pillar. The shape of the analysis model is set, for example, by diverting data created by general-purpose three-dimensional CAD (Computer Aided Design) software to the computer program 17 or by input from the input device 14. Further, data (input value) necessary for the analysis is set based on an input from the input device 14 or as a value given in advance. In the present embodiment, at least shape data (for example, CAD data) of an object to be analyzed and material characteristic data are included in the input value of the CAE analysis.

  The functions of the computer program 17 for CAE analysis are schematically shown in FIG. The computer program 17 includes a model creation unit 17a, a condition setting unit 17b, and an analysis unit 17c. Each of these elements may be realized by an electronic circuit (hardware), or a part of these functions may be provided as hardware and the other part may be software.

  The model creation unit 17a creates a model to be analyzed. In the present embodiment, a case where a deformation mode of a bumper at the time of a vehicle collision is analyzed will be described as an example. In this case, the model creation unit 17a creates an analysis model by modeling the bumper shape and dividing it into a plurality of meshes.

  The condition setting unit 17b sets conditions used for analysis. In this case, the load condition (the magnitude and direction of the load) at the time of the collision is set, and the constraint condition of the bumper is set. Moreover, the material characteristic data acquired by the measuring method mentioned above is used for the material characteristic value corresponding to the material of the bumper. That is, before the CAE analysis which is the main processing, a plurality of test pieces 3 are formed of the same material as the material of the object to be analyzed (in this case, the bumper), and the test is performed by the test apparatus 1 described above. Every time, material characteristic data (material characteristic value) is acquired.

In the measurement method using the test apparatus 1 described above, the stress triaxiality σ _TR can be intermittently changed and the test can be performed to obtain the material characteristic value as a continuous value. It is possible to provide the material characteristic value for the (form) as an input value for the CAE analysis. For this reason, the analysis accuracy of CAE analysis is improved. Moreover, in the measurement method described above, since dynamic damage data can be acquired, the analysis accuracy in the collision simulation is also improved.
The analysis unit 17 c performs CAE analysis using the analysis model created by the model creation unit 17 a and the conditions set by the condition setting unit 17 b and outputs the analysis result to the output device 15.

  FIG. 9 shows a procedure (analysis method) when the computer 10 executes the computer program 17. In step T1, data (input value) of an object serving as an analysis model is prepared or input from the external storage device 13, the input device 14, or the like. This data includes at least shape data and material property data (preparation step). In step T2, the model creation unit 17a creates an analysis model for CAE analysis (model creation process).

  In subsequent step T3, the above-described conditions are set by the condition setting unit 17b (condition setting step). Then, CAE analysis is executed by the CPU 11 using the input values and analysis conditions set in steps T1 and T3 and the analysis model created in step T2 (step T4, analysis process), and an analysis result is output. (Step T5, output process).

[5. Action, effect]
(1) In the test piece 3 described above, by arranging the two holes 7 so as to be point-symmetric on the circumference 6 around the symmetry point 5 of the base material 4, the stress triaxial at the symmetry point 5. The degree σ _TR can be changed. For example, if the two holes 7 are arranged on the center line _{CW in the} width direction (aligned in a straight line in the longitudinal direction), the stress triaxiality σ _TR at the symmetry point 5 can be made zero. Also, placing the two holes 7 on the longitudinal center line C _L and (arranged in a straight line in the width direction), the stress 3 Jikudo sigma _TR in symmetry points 5 can be 2/3.

That is, if the test piece 3 described above, for example, shear breakage strain epsilon _FA (rupture properties) or biaxial tensile failure strain epsilon _FA of or strain failure of deformation mode between the shear and uniaxial tension epsilon Various fracture strains such as _FA can be measured using the uniaxial tensile tester 2. In other words, the test piece 3 can measure the material characteristic values such as the failure strain ε _FA as an intermittent value by the uniaxial tensile tester 2, thereby simplifying the measurement and reducing the test cost. Can be reduced. Furthermore, a continuous material characteristic value can also be acquired by complementing the value obtained by the measurement.

Moreover, since the test piece 3 only needs to perform the simple process of processing the hole 7 and the slit 8 on the rectangular flat base 4, the processing cost can be reduced. Furthermore, in the case of this test piece 3, since the influence of heat at the time of processing the hole 7 and the slit 8 is difficult to be exerted on the symmetry point 5, and there is no processing in the thickness direction, an accurate material characteristic value is measured. can do.
Moreover, if it is this test piece 3, since it can install in a high-speed tension test apparatus, the collision data when a biaxial tensile force, a shear force, etc. act can be acquired. That is, with this test piece 3, data that can be used in various collision modes (collision tests) can be acquired.

(2) In the above-described test piece 3, the range R in which the slit 8 is sandwiched between two perpendiculars extending from both edge ends 7 b and 7 b in the longitudinal direction of the hole portion 7 to the edge portion 4 e of the substrate 4. Therefore, the route F through which the tensile force passes can be created while simplifying the shape of the test piece 3.
(3) Furthermore, since the test piece 3 described above has the slit 8 extending in a direction orthogonal to the edge 4 e of the base material 4, the slit processing can be easily performed.

(4) The above-described test apparatus 1 includes a test machine 2 and a plurality of test pieces 3 having different shapes. According to such a test apparatus 1, continuous or intermittent data of material characteristic values such as the failure strain ε _FA is acquired using the test piece 3 in which the stress triaxiality σ _TR is intermittently changed. be able to. In addition, the uniaxial tensile testing machine 2 can hold down test cost low compared with the apparatus which measures the failure strain of a shear, and the apparatus which measures the failure strain of a biaxial tension. Therefore, according to this test apparatus 1, compared with the case where the test apparatus only for shearing and biaxial tension is used, it can also contribute to reduction of test cost. Furthermore, if a high-speed tensile tester is used as the tester 2, collision data (dynamic breakage) can be acquired.

(5) In the measurement method described above, since such a test apparatus 1 is used, continuous or intermittent data of material property values can be acquired at low cost.
(6) Moreover, in the analysis apparatus, analysis method, and analysis program mentioned above, since the material characteristic data acquired by the measurement method mentioned above is used as an input value of CAE analysis, analysis accuracy can be improved.

[6. Modified example]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.
Test piece 3 described above, the center point 7c of the hole portion 7, but is provided so as to be located within a range of 90 degrees to the longitudinal center line C _L of the widthwise center line C _W, center The point 7c may be provided beyond this range. Moreover, the slit 8 may be provided in parts other than the range R, and may be extended in a direction that is not orthogonal to the edge 4e.
In addition, the usage method of the data (material characteristic value) measured using the test piece 3 mentioned above is not specifically limited, You may use it besides the analysis mentioned above.

DESCRIPTION OF SYMBOLS 1 Test apparatus 2 Test machine 3 Test piece 3A Fixed part 3B Measuring part 4 Base material 4e Edge of width direction 5 Symmetry point (center point)
6 circumference 7 hole 7b edge in longitudinal direction 7c center point 8 slit 10 analyzer 11 CPU
15 output device 17 computer program (analysis program)
σ _TR stress triaxiality ε _FA failure strain
C _W width direction center line
C _L Longitudinal center line
R range

Claims (8)

A fixed portion that is provided at both ends in the longitudinal direction of a rectangular flat plate-like base material and fixed to a testing machine;
A measuring unit provided in a middle portion in the longitudinal direction of the base material, and formed in a point-symmetric shape with respect to both center points in the longitudinal direction and the width direction of the base material,
The measurement part is formed from each of two hole parts that are drilled in the base material and each center point is arranged on a circumference centered on the symmetry point, and both edges in the width direction of the base material. And a slit that is cut out to reach each of the two holes. The slit is arranged in a range sandwiched between two perpendiculars extending from each of both edge ends in the longitudinal direction of the hole portion to an edge portion in the width direction of the base material. The test piece according to claim 1. The test piece according to claim 1, wherein the slit extends in a direction orthogonal to an edge portion in the width direction of the base material. A uniaxial tensile tester or a high-speed tensile tester as the tester;
A plurality of the test pieces according to any one of claims 1 to 3,
The test apparatus according to claim 1, wherein the plurality of test pieces have different positions of the two holes. Using the test apparatus according to claim 4, measuring the characteristic value of the symmetry point in the test piece by fixing the fixing portion of each test piece to the testing machine and performing a tensile test. A characteristic measuring method. An analyzer for simulating stress distribution or deformation mode by a CAE analysis when a load is applied to an object made of the same material as the test piece according to any one of claims 1 to 3,
A CPU that executes the CAE analysis using input values including at least the shape data and material property data of the object;
An output device that outputs an analysis result of the CAE analysis by the CPU;
The analysis device according to claim 5, wherein the material property data includes the property value measured by the measurement method according to claim 5. The stress distribution or deformation mode when a load is applied to the object, using at least shape data and material property data of the object made of the same material as the test piece according to any one of claims 1 to 3 as input values. An analysis method for causing a computer to execute a process to be simulated by CAE analysis,
A model creation step of creating an analysis model of the CAE analysis;
A condition setting step for setting conditions for the CAE analysis;
An analysis step of performing the CAE analysis using the analysis model and the conditions,
The analysis method according to claim 5, wherein the material property data includes the property value measured by the measurement method according to claim 5. The stress distribution or deformation mode when a load is applied to the object, using at least shape data and material property data of the object made of the same material as the test piece according to any one of claims 1 to 3 as input values. An analysis program for causing a computer to execute processing simulated by CAE analysis,
A model creation step of creating an analysis model of the CAE analysis;
A condition setting step for setting conditions for the CAE analysis;
An analysis step of performing the CAE analysis using the analysis model and the conditions,
6. The analysis program according to claim 5, wherein the material property data includes the property value measured by the measurement method according to claim 5.

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