A high-speed rotating disc sample material mechanical properties testing device and test method

Abstract

The present invention discloses a high-speed rotating disc sample material mechanical property testing device and test method, which utilizes the high-speed rotating disc sample to produce radial displacement of material particles under the action of the rotating inertial force. The magnitude of the radial displacement is related to the geometric shape and size of the turntable, the rotation speed and the turntable material. Based on this principle, a material mechanical property test method is formed and a test device is constructed. The device can accurately measure the entire deformation process of the disc sample from initial deformation to near tensile instability. Based on the experimental method, the present invention also provides a method for obtaining the material stress-strain relationship, by using a computer-simulated U R ‑nSimulation relationship curve and experimentally measured U * R ‑n test relationship curves, and modify the stress-strain relationship mathematical model and initial parameters according to the comparison results, so that U R ‑nThe simulated relationship curve is getting closer to U * R ‑n test relationship curve until a quasi-real stress-strain relationship is obtained.

Description

Technical Field

[0001] The invention relates to the technical field of material mechanical property testing, and in particular to a high-speed rotating disc sample material mechanical property testing device and a testing method. Background Art

[0002] With the rapid development of computer technology, numerical simulation methods are widely used in the analysis, design and research of engineering structures. The credibility of numerical simulation results depends on the accuracy of structural geometric modeling, constraints and loads, and material performance parameters. As far as material mechanical performance parameters are concerned, the traditional reliance on individual parameters (such as elastic modulus, yield strength, tensile strength, etc.) can no longer meet the needs of numerical simulation for material performance characterization. There is an urgent need for a larger strain range and more accurate material mechanical stress-strain relationship.

[0003] The existing material mechanical properties test methods mainly include uniaxial tension, cross-shaped specimen biaxial tension, small punching, hydraulic bulging test, etc. At present, the most commonly used uniaxial tension test method is that the tensile specimen is usually made by machining, and the cross-section of the specimen can be circular, rectangular, polygonal, annular, etc. (ISO 6892-1:2019Metallic materials-Tensiletesting-Part1:Method of test at room temperature; GB / T 228.1-2021Metallic materials tensile testing Part 1: Room temperature test method). The advantages of the uniaxial tension test method are simple specimens and traditional methods. The main disadvantages are: 1) The measured stress and strain are average values ​​in a certain sense (extensometer gauge range or chuck distance range); 2) The overall state is in a uniaxial stress state, and it is difficult to accurately predict the mechanical behavior of the biaxial stress state; 3) It is easy to enter the local deformation stage earlier, and the ultimate strain value is small (usually less than half of the biaxial tension test), and the stress-strain relationship of the material in a large strain range cannot be obtained.

[0004] The "cross" specimen biaxial tensile test is suitable for plates (GB / T 36024-2018 Metallic materials-Sheet and strip-Biaxial tensile testing method using a cruciform test piece; ISO 16842:2021Metallic materials-Sheet and strip-Biaxial tensile testing method using a cruciform test piece). The specimen is concise and intuitive and can directly reflect the biaxial stress state. In order to transfer the rupture from the branch to the center and obtain a highly uniform deformation field in the central working area of ​​the specimen, various optimization attempts are made on the structural form of the "cross" specimen, mainly including the optimized structure of the root fillet, central thinning, branch grating and their combination. The stress obtained from the working area by this test method is much lower than the ultimate tensile strength, and the maximum strain obtained in the measuring area is only 1 / 4 of the strain limit (L.Nasdala, AHHusni.Determination of yield surfaces in accordance with ISO 16842using an optimized cruciform testspecimen.Experimental Mechanics,2020,(60):815-832)

[0005] The small punch test usually refers to the small punch bending test (Manahan M P. The development of aminiaturized disk bend test for the determination of post-irradiation mechanical behavior. Dissertation. Massachusetts Institute of Technology, Boston, 1982; GB / T 29459.2-2012 Small punch test method for metal materials in service pressure equipment Part 2: Test method for tensile properties at room temperature). The advantages of the small punch test method are: 1) small sample size (generally 3 to 10 mm); 2) on-site in-service sampling. In the study of establishing material stress-strain relationship, the accuracy and repeatability of the experimental results are still far behind the traditional test methods, and the data correlation processing is far from perfect. Due to the small size of the sample, the eccentricity of the punch will significantly increase the stiffness of the sample and reduce the accuracy of the experiment.

[0006] The periphery of the hydraulic bulge test specimen is fixed and clamped, and static pressure is applied laterally. As the load increases, the bulge deformation increases, thereby obtaining the mechanical properties of the material (ISO 16808:2022Metallic materials-Sheet and strip-Determination of biaxial stress-strain curve by means of bulge test with optical measuring systems). The advantages of this test method are: 1) The specimen preparation is very simple; 2) The test results are highly repeatable; 3) The increase in curvature at the local deformation site inhibits the further increase in the stress level, so that the local large deformation is transferred in time, so that the specimen obtains sufficient deformation; 4) The bulge test can consider the mechanical behavior of the biaxial stress state. The complexity of the bulging test lies in: 1) the bulging curvature of the specimen varies with different longitudinal positions and changes continuously with deformation; 2) there is no uniform stress-strain field, and there is a large stress-strain gradient; 3) the wall thickness is non-uniformly thinned; 4) it is very difficult to accurately measure the geometry and deformation under pressure, and safety reasons make it almost impossible to measure when close to the deformation limit; 5) after unloading the pressure, elastic recovery will cause a decrease in measurement accuracy; 6) the size of the elastic recovery is different at different deformation stages; 7) it is difficult to measure the inner surface contour.

[0007] In summary, the existing material mechanical properties test methods have the following problems: complex testing, low measurement accuracy, and inability to obtain the stress-strain relationship of the material over a large strain range. Summary of the invention

[0008] In order to solve the technical problems of existing material mechanical property testing methods, such as complex testing, low measurement accuracy, and inability to obtain the stress-strain relationship of materials in a large strain range, the present invention provides a high-speed rotating disc specimen material mechanical property testing device and a testing method.

[0009] The technical solution adopted by the present invention is:

[0010] A high-speed rotating disc sample material mechanical property testing device, comprising a test bench base, a variable frequency speed regulating motor installed on the test bench base, a test shell main housing and a test shell side housing, a power input shaft rotatably installed in the test shell main housing through a single high-speed bearing at one end, an outer end support shaft rotatably installed in the test shell side housing through two high-speed bearings at one end, a disc sample coaxially fixedly connected to the power input shaft and the other end of the outer end support shaft through a central area, a speed increaser connected to the variable frequency speed regulating motor at the input end and the power input shaft at the output end, a displacement sensor installed on the test shell main housing for measuring the radial displacement of the outer circumference of the disc sample, a speed sensor installed on the test shell main housing for measuring the speed of the disc sample, a data acquisition system connected to the displacement sensor and the speed sensor, and a computer connected to the data acquisition system;

[0011] The data acquisition system synchronously collects the analog signals generated by the displacement sensor and the speed sensor respectively, and converts them into digital signals and transmits them to the computer. The acquisition control and data storage are implemented through the software in the computer.

[0012] Furthermore, the disc specimen is an axisymmetric structure, and its disc surface is divided into a centrifugal zone, a centrifugal transition zone, a main deformation zone, a central transition zone and a central zone from the outer circumference to the center of the circle; the central zone is mainly used for the suspended support of the disc specimen, the main deformation zone is mainly used to generate radial deformation, the centrifugal zone is mainly used to generate centrifugal force, the centrifugal transition zone is mainly used to connect the centrifugal zone and the main deformation zone, and the central transition zone is mainly used to connect the main deformation zone and the central zone.

[0013] Furthermore, the main deformation zone is in the shape of a circular ring with uniform thickness, which is the thinnest and has the largest area; the centrifugal zone is in the shape of a circular ring with uniform thickness, which is greater than the thickness of the main deformation zone and is of the same order of magnitude as the effective thickness of the central zone; the outer circle thickness of the centrifugal transition zone is equal to the thickness of the centrifugal zone, and the inner circle thickness is equal to the thickness of the main deformation zone; the outer circle thickness of the central transition zone is equal to the thickness of the main deformation zone, and the inner circle thickness is equal to the effective thickness of the central zone, and the effective thickness is the minimum thickness of the central zone after deducting the axial length of the connecting section.

[0014] Furthermore, the area of ​​the main deformation zone is 50% to 65% of the positive projection area of ​​the disk specimen, the ratio of the area of ​​the main deformation zone to the area of ​​the centrifugal zone is (2.4 to 2.9):1, and the ratio of the thickness of the main deformation zone to the thickness of the centrifugal zone is 1:(14 to 25).

[0015] Furthermore, a rotating shaft outer end cover is provided on the outer side of the test shield side box body, and a power rotating shaft end cover is provided on the outer side of the test shield main box body.

[0016] Furthermore, the disc sample is detachably connected to the power input shaft and the outer end support shaft.

[0017] The test method of any of the above-mentioned high-speed rotating disk specimen material mechanical properties testing devices comprises the following steps:

[0018] 7.1. By controlling the variable frequency speed regulating motor, the speed of the disc sample is slowly increased from zero to the set value. As the speed continues to increase, the radial displacement of the disc sample increases accordingly, and the radial displacement reaches the maximum at the outer circumference of the disc sample. In this process, the displacement sensor measures the radial displacement of the outer circumference of the disc sample, and the speed sensor measures the speed of the disc sample.

[0019] 7.2. The data acquisition system synchronously collects the analog signals generated by the displacement sensor and the speed sensor, converts them into digital signals and transmits them to the computer. The acquisition control and data storage are implemented through the software in the computer.

[0020] The method for obtaining the material stress-strain relationship based on the above test method comprises the following steps:

[0021] 8.1. Analyze and evaluate the critical speed of the single rotor shaft system consisting of the disc specimen, the power input shaft and the outer end support shaft, and formulate a speed increase plan;

[0022] 8.2. Prepare the disc sample and make precise measurements of its geometric dimensions;

[0023] 8.3. Assemble the prepared disk sample on the test bench and make a preliminary measurement of the relationship between radial displacement and rotation speed to obtain the radial displacement-rotation speed curve, i.e., U * R -n experimental relationship curve;

[0024] 8.4. Select the stress-strain relationship mathematical model and initial parameters based on the obtained radial displacement-speed curve characteristics;

[0025] 8.5. Model the disk specimen with its real geometric parameters and perform finite element analysis on it to obtain the simulation result of the relationship between the radial displacement and the rotation speed of the outer circumference of the specimen, i.e., U R -n simulated relationship curve;

[0026] 8.6. Change U R -n simulation relationship curve and U * R -n test relationship curves to see whether they meet the comparison criteria. If they exceed the tolerance ε, the stress-strain relationship mathematical model and initial parameters are modified according to the comparison results, and the finite element analysis of the disc specimen is re-performed to make U R -n simulation relationship curve is constantly approaching U * R-n test relationship curve until the comparison criterion is met, at which point the stress-strain relationship is the quasi-real stress-strain relationship;

[0027] Among them, U R represents the simulated radial displacement value at the outer circumference of the specimen, n represents the rotation speed of the specimen, U * R Represents the measured value of radial displacement at the outer circumference of the specimen, and ε is the set tolerance.

[0028] Beneficial effects of the present invention:

[0029] (1) In the present invention, when the disc sample rotates at high speed, under the action of the rotational inertia force, the material particles produce radial displacement, the diameter of the disc becomes larger, and the thickness becomes thinner. The size of the radial displacement of the disc is related to the geometric shape and size of the disc, the rotation speed and the material of the disc. Based on this principle, a material mechanical property test method is formed and a test device is constructed, so that the maximum radial displacement position of the disc sample is always stable at the outer periphery of the disc sample from the initial deformation to the plastic deformation, which is convenient for accurate positioning of the measurement and easy to realize the measurement of the entire process from the initial deformation to the deformation close to tensile instability, thereby making the measurement strain range close to the full range and the measurement result more accurate.

[0030] (2) The disc specimen of the present invention is an axisymmetric structure and is easy to manufacture. During the test at room temperature, only the radial displacement and rotation speed need to be measured, and no complicated measuring clamping device is required, thereby greatly simplifying the structure of the test device.

[0031] (3) The disc specimen of the present invention is provided with a main deformation zone and a centrifugal zone to ensure that within a certain rotation speed limit (such as 40,000 r / min), a sufficiently large deformation is generated, and stress-strain relationship measurement close to the full strain range can be achieved.

[0032] (4) The present invention uses the geometric measurement data of the disk sample for modeling, so that the numerical simulation results are closer to the experimental results. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural schematic diagram of a high-speed rotating disc sample material mechanical property testing device of the present invention.

[0034] Figure 2 It is a schematic structural diagram of the disc sample of the present invention.

[0035] Figure 3 It is a flowchart of the method for obtaining the material stress-strain relationship of the present invention.

[0036] In the figure: 1. variable frequency speed regulating motor, 2. test bench base, 3. speed increaser, 4. power shaft end cover, 5. power input shaft, 6. disc specimen, 6-1. centrifugal zone, 6-2. centrifugal transition zone, 6-3. main deformation zone, 6-4. central transition zone, 6-5. central zone, 7. test shell side box, 8. high speed bearing, 9. outer end supporting shaft, 10. shaft outer end cover, 11. test shell main box, 12. displacement sensor, 13. speed sensor, 14. data acquisition system, 15. computer. DETAILED DESCRIPTION

[0037] The present invention is further described below in conjunction with specific examples to facilitate understanding of the present invention, but the present invention is not limited thereto.

[0038] Example 1

[0039] See also Figure 1 and Figure 2 The present embodiment provides a high-speed rotating disc sample material mechanical property testing device, including a variable frequency speed regulating motor 1, a test bench base 2, a speed increaser 3, a power shaft end cover 4, a power input shaft 5, a disc sample 6, a test casing side box 7, a high-speed bearing 8, an outer end supporting shaft 9, a shaft outer end cover 10, a test casing main box 11, a displacement sensor 12, a speed sensor 13, a data acquisition system 14, and a computer 15.

[0040] The central area 6-5 of the disc sample 6 is connected to the power input shaft 5 and the outer end support shaft 9 respectively to form a single rotor shaft system. The power input shaft 5 is matched with a single high-speed bearing 8 through its journal, and is placed in the main box body 11 of the test shell, which is an outrigger beam structure. The outer end support shaft 9 is matched with two high-speed bearings 8 through its journal, and is placed in the side box body 7 of the test shell, which is a cantilever beam structure. The connection structure of the power input shaft 5, the outer end support shaft 9 and the central area 6-5 of the disc sample 6 is designed as a quick detachable connection method, such as providing a tongue-and-groove connection or a hole pin connection adapted to the power input shaft 5 and the outer end support shaft 9 at both ends of the central area 6-5 of the disc sample 6.

[0041] The disc sample 6 is an axisymmetric structure, and its disc surface is divided into a centrifugal zone 6-1, a centrifugal transition zone 6-2, a main deformation zone 6-3, a central transition zone 6-4 and a central zone 6-5 from the outer circumference to the center of the circle. The central zone 6-5 is formed by the center of the disc body protruding to both sides, and its thickness after deducting the connection section is of the same order of magnitude as the thickness of the centrifugal zone 6-1. The centrifugal zone 6-1 is in the form of a circular ring with equal thickness, and its area is 16% to 22% of the positive projection area of ​​the disc sample 6, and the ratio of its thickness to the thickness of the main deformation zone 6-3 is (14 to 25): 1; the main deformation zone 6-3 is in the form of a circular ring with equal thickness, and its area is 50% to 65% of the positive projection area of ​​the disc sample 6. The centrifugal transition zone 6-2 is in the shape of a ring whose thickness continuously changes along the radial direction, and its outer circle thickness is equal to the thickness of the centrifugal zone 6-1, and its inner circle thickness is equal to the thickness of the main deformation zone 6-3; the central transition zone 6-4 is in the shape of a ring whose thickness continuously changes along the radial direction, and its outer circle thickness is equal to the thickness of the main deformation zone 6-3, and its inner circle thickness is equal to the effective thickness of the central zone 6-5, which is the minimum thickness of the central zone 6-5 after deducting the axial length of the connecting section.

[0042] The main deformation zone 6-3 has the largest area and the thinnest thickness, and is mainly used to generate radial deformation. The centrifugal zone 6-1 is mainly used to generate centrifugal force. The centrifugal transition zone 6-2 is mainly used to transitionally connect the centrifugal zone 6-1 and the main deformation zone 6-3. The central transition zone 6-4 is mainly used to connect the main deformation zone 6-3 and the central zone 6-5. The centrifugal transition zone 6-2 and the central transition zone 6-4 are set to prevent the main deformation zone 6-3 from tearing before reaching the maximum strain during the test.

[0043] The displacement sensor 12 is non-contact type, and a total of three are used in combination, which are respectively placed on the top, front and rear of the test shell main box 11 to measure the linear displacement of the outer circumference of the disc sample 6. The ranges of the three displacement sensors are continuous and overlap to a certain extent. After debugging and calibration before measurement, the total measurement range is from 3μm to 10mm. The speed sensor 13 is placed on the side panel of the test shell main box 11. The rotation drive of the disc sample 6 comes from the variable frequency speed regulating motor 1 and the speed increaser 3 directly connected to it. The entire test device is placed on the test bench base 2.

[0044] The working principle of the present invention is: when the disc sample 6 rotates at high speed, under the action of inertial force, the material particles produce radial displacement, the diameter of the disc becomes larger, and the thickness becomes thinner; the size of the radial displacement is related to the geometric shape and size of the disc, the rotation speed and the material of the turntable. During the deformation process of the sample, the geometric relationship (shape and geometric size), physical relationship (material stress-strain), and static equilibrium relationship (constraint and rotational inertial force load) must be satisfied. Based on this principle, a material mechanical property test method is formed and a test device is constructed.

[0045] Example 2

[0046] This embodiment provides a test method for the high-speed rotating disk sample material mechanical property test device as described in Embodiment 1, comprising the following steps:

[0047] 2.1. During the test, the speed of the disc sample 6 is slowly increased from zero to a set value by controlling the variable frequency speed regulating motor 1. As the speed continues to increase, the radial displacement of the disc sample 6 increases accordingly, and the radial displacement reaches the maximum at the outer circumference of the disc sample 6. During this process, the displacement sensor 12 measures the radial displacement of the outer circumference of the disc sample 6, and the speed sensor 13 measures the speed of the disc sample 6.

[0048] 2.2. The data acquisition system 14 synchronously acquires analog signals generated by the displacement sensor 12 and the rotation speed sensor 13, respectively, and converts them into digital signals and transmits them to the computer 15. The acquisition control and data storage are implemented through the software in the computer 15.

[0049] Example 3

[0050] See also Figure 3 This embodiment provides a method for obtaining a material stress-strain relationship based on the test method described in Embodiment 2, comprising the following steps:

[0051] 21. Perform critical speed analysis and evaluation on the single rotor rotating shaft system consisting of the disc sample (6), the power input shaft (5) and the outer end support shaft (9), and formulate a speed increase plan;

[0052] 22. Prepare a disk sample (6), and perform precise measurement of the geometric dimensions of the disk sample (6);

[0053] 23. Assemble the prepared disk sample (6) on the test bench and perform a preliminary measurement of the relationship between radial displacement and rotation speed to obtain the radial displacement-rotation speed curve, i.e., U * R -n experimental relationship curve;

[0054] 24. Select the stress-strain relationship mathematical model and initial parameters based on the obtained radial displacement-speed curve characteristics;

[0055] 26. The real geometric parameters of the disk sample (6) are used to model the disk sample (6), and a finite element analysis is performed on the disk sample (6) to obtain the simulation result of the relationship between the radial displacement of the outer circumference of the sample and the rotation speed, that is, U R -n simulated relationship curve;

[0056] 28. Will U R -n simulation relationship curve 26 and U * R-n test relationship curve 27 is compared to see whether it meets the comparison criteria. If it exceeds the tolerance ε, the stress-strain relationship mathematical model and initial parameters 25 are modified according to the comparison results, and the finite element analysis of the disk sample (6) is re-performed so that U R -n simulation relationship curve is constantly approaching U * R -n test relationship curve until the comparison criterion is met, at which point the stress-strain relationship is the quasi-real stress-strain relationship29;

[0057] Among them, U R represents the simulated radial displacement value at the outer circumference of the specimen, n represents the rotation speed of the specimen, U * R Represents the measured value of radial displacement at the outer circumference of the specimen, and ε is the set tolerance.

[0058] The present invention utilizes the principle that the disc specimen jointly follows the deformation geometric relationship, material constitutive relationship and static equilibrium relationship during the rotational deformation process, combines the finite element analysis method, and adopts the characteristic parameter of the disc specimen's outer circumference radial displacement which is easy to measure. By comparing the test value with the simulation value, the real material stress-strain relationship is gradually approached to obtain a quasi-real material stress-strain relationship.

[0059] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications are also within the protection scope of the present invention.

Claims

1. A high-speed rotating disc sample material mechanical properties testing device, characterized in that: The invention comprises a test bench base (2), a variable frequency speed regulating motor (1) mounted on the test bench base (2), a test shell main housing (11) and a test shell side housing (7), a power input shaft (5) rotatably mounted in the test shell main housing (11) at one end through a single high-speed bearing (8), an outer end support shaft (9) rotatably mounted in the test shell side housing (7) at one end through two high-speed bearings (8), and a disc test shaft (6-5) coaxially fixedly connected to the other ends of the power input shaft (5) and the outer end support shaft (9) through a central area (6-5). A sample (6), a speed increaser (3) whose input end is connected to a variable frequency speed regulating motor (1) and whose output end is connected to a power input shaft (5), a displacement sensor (12) mounted on a test casing main body (11) for measuring the radial displacement of the outer circumference of the disc sample (6), a speed sensor (13) mounted on the test casing main body (11) for measuring the speed of the disc sample (6), a data acquisition system (14) connected to the displacement sensor (12) and the speed sensor (13), and a computer (15) connected to the data acquisition system (14); The data acquisition system (14) synchronously acquires analog signals generated by the displacement sensor (12) and the rotation speed sensor (13), respectively, and converts them into digital signals and transmits them to the computer (15). The acquisition control and data storage are implemented through the software in the computer (15).

2. A high-speed rotating disc sample material mechanical properties testing device according to claim 1, characterized in that: The disc specimen (6) is an axisymmetric structure, and its disc surface is divided into a centrifugal zone (6-1), a centrifugal transition zone (6-2), a main deformation zone (6-3), a central transition zone (6-4) and a central zone (6-5) in sequence from the outer circumference to the center of the circle; the central zone (6-5) is mainly used for the suspended support of the disc specimen (6), the main deformation zone (6-3) is mainly used for generating radial deformation, the centrifugal zone (6-1) is mainly used for generating centrifugal force, the centrifugal transition zone (6-2) is mainly used for connecting the centrifugal zone (6-1) and the main deformation zone (6-3), and the central transition zone (6-4) is mainly used for connecting the main deformation zone (6-3) and the central zone (6-5).

3. A high-speed rotating disc sample material mechanical properties testing device according to claim 2, characterized in that: The main deformation zone (6-3) is in the shape of a circular ring with uniform thickness, and its thickness is the thinnest and its area is the largest; the centrifugal zone (6-1) is in the shape of a circular ring with uniform thickness, and its thickness is greater than that of the main deformation zone (6-3) and is of the same order of magnitude as the effective thickness of the central zone (6-5); the outer circle thickness of the centrifugal transition zone (6-2) is equal to the thickness of the centrifugal zone (6-1), and the inner circle thickness is equal to the thickness of the main deformation zone (6-3); the outer circle thickness of the central transition zone (6-4) is equal to the thickness of the main deformation zone (6-3), and the inner circle thickness is equal to the effective thickness of the central zone (6-5), and the effective thickness is the minimum thickness of the central zone (6-5) after deducting the axial length of the connecting section.

4. A high-speed rotating disc sample material mechanical properties testing device according to claim 3, characterized in that: The area of ​​the main deformation zone (6-3) is 50% to 65% of the positive projection area of ​​the disc sample (6), the ratio of the area of ​​the main deformation zone (6-3) to the area of ​​the centrifugal zone (6-1) is (2.4 to 2.9):1, and the ratio of the thickness of the main deformation zone (6-3) to the thickness of the centrifugal zone (6-1) is 1:(14 to 25).

5. The high-speed rotating disc sample material mechanical properties testing device according to claim 1, characterized in that: A rotating shaft outer end cover (10) is provided on the outer side of the test shield side box body (7), and a power rotating shaft end cover (4) is provided on the outer side of the test shield main box body (11).

6. The high-speed rotating disk sample material mechanical properties testing device according to claim 1, characterized in that: The disc sample (6) is detachably connected to the power input shaft (5) and the outer end supporting rotating shaft (9).

7. The test method of the high-speed rotating disk sample material mechanical property testing device according to any one of claims 1 to 6, characterized in that: The following steps are involved: 7.

1. By controlling the variable frequency speed regulating motor (1), the rotation speed of the disc sample (6) is slowly increased from zero to a set value. As the rotation speed continues to increase, the radial displacement of the disc sample (6) increases accordingly, and the radial displacement reaches a maximum at the outer circumference of the disc sample (6). In this process, the displacement sensor (12) measures the radial displacement of the outer circumference of the disc sample (6), and the rotation speed sensor (13) measures the rotation speed of the disc sample (6). 7.

2. The data acquisition system (14) synchronously acquires analog signals generated by the displacement sensor (12) and the rotation speed sensor (13), converts them into digital signals and transmits them to the computer (15). The acquisition control and data storage are implemented through the software in the computer (15).

8. A method for obtaining a material stress-strain relationship based on the test method of claim 7, characterized in that: The following steps are involved: 8.

1. Perform critical speed analysis and evaluation on the single rotor shaft system consisting of the disc sample (6), the power input shaft (5) and the outer end support shaft (9), and formulate a speed increase plan; 8.

2. preparing a disk sample (6) and performing precise measurement of the geometric dimensions of the disk sample (6); 8.

3. Assemble the prepared disk sample (6) on the test bench and make a preliminary measurement of the relationship between radial displacement and rotation speed to obtain the radial displacement-rotation speed curve, namely U * R -n experimental relationship curve; 8.

4. Select the stress-strain relationship mathematical model and initial parameters based on the obtained radial displacement-speed curve characteristics; 8.

5. Model the disk specimen (6) with its real geometric parameters and perform finite element analysis on the disk specimen (6) to obtain the simulation result of the relationship between the radial displacement of the outer circumference of the specimen and the rotation speed, i.e., U R -n simulated relationship curve; 8.

6. Change U R -n simulation relationship curve and U * R -n test relationship curves to see whether they meet the comparison criteria. If they exceed the tolerance ε, the stress-strain relationship mathematical model and initial parameters are modified according to the comparison results, and the finite element analysis of the disk specimen (6) is re-performed so that U R -n simulation relationship curve is constantly approaching U * R -n test relationship curve until the comparison criterion is met, at which point the stress-strain relationship is the quasi-real stress-strain relationship; Among them, U R represents the simulated radial displacement value at the outer circumference of the specimen, n represents the rotation speed of the specimen, U * R Represents the measured value of radial displacement at the outer circumference of the specimen, and ε is the set tolerance.

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