Bidirectional loading small punching clamp and small-damage punching creep fatigue test equipment

Abstract

The invention discloses a bidirectional loading small punching clamp and damage small punching creep fatigue test equipment, and belongs to the technical field of small sample small punching creep-fatigue tests.The bidirectional loading small punching clamp is composed of an upper die, a lower die, an upper punching rod, a lower punching rod, a pressing block, a cushion block, a supporting body and a small punching sample; the small-damage punching creep fatigue test equipment is composed of a bidirectional loading small punching clamp, a bidirectional loading system, a bidirectional strain measurement system and a total system. The method has the characteristics of high precision, high stability, high reliability and the like, can be widely applied to creep fatigue performance evaluation of various materials, and provides powerful support for material research and application.

Description

Technical Field

[0001] The invention relates to the technical field of micro-sample small punching creep-fatigue testing, in particular to a bidirectional loading small punching fixture and a damaged small punching creep fatigue testing device. Background Art

[0002] In industries such as nuclear power and petrochemicals, pressure pipes, vessels and other metal parts will gradually deteriorate and become damaged as they age when operating under high temperature, high pressure and irradiation conditions. The physical and mechanical properties of the materials decay accordingly, and this degradation may lead to sudden failures of pipes and vessel equipment, resulting in significant economic losses and potential casualties. Therefore, it is of great practical significance to accurately assess the remaining life of these service materials during the creep process to ensure the safe and stable operation of high-temperature components.

[0003] Currently, it is common practice to use destructive methods to cut samples from equipment in use, such as cutting from a pipe. Then, conventional uniaxial creep tests are used to evaluate the mechanical properties and remaining life of the material. However, this testing method is expensive, causes great damage to the equipment, and sometimes it is even impossible to prepare specimens from small equipment. These limitations have, to a certain extent, hindered the widespread application of this technology on service components.

[0004] The small punching test technology uses tiny specimens and has the dual advantages of "sampling" and "non-destructive". This technology is very suitable for situations where traditional specimens cannot be taken out or sampling is uneconomical, making it possible to non-destructively evaluate the remaining life of in-service high-temperature components. . This test method requires very thin optical discs, similar to those required for transmission electron microscopes (about 8 mm in diameter and 0.5 mm thick), which is of great significance for testing without destroying the integrity of the component. The small punching test technology has been applied to a variety of metal materials and composite materials in the high-temperature field. Although the small punching technology has been widely used in high-temperature service components, its test content is mainly limited to creep testing, and lacks the implementation of creep fatigue testing.

[0005] Traditional small punching specimens can only perform mechanical behaviors such as creep and stretching, but fatigue and creep fatigue behaviors cannot be fully understood. At the same time, many in-service equipment operate in atmospheric environments such as salt spray and hydrogen sulfide. To determine the mechanical properties of materials in atmospheric environments, small punching tests need to be performed in atmospheric environments. Therefore, it is urgent to design a micro-sampling small punching creep fatigue test device for high-temperature service components to solve the problems of traditional large-size specimens in high-temperature creep tests, such as difficulty in specimen preparation, high cost, and destructiveness to in-service components. Summary of the invention

[0006] In order to break through the performance test that can only be obtained by a single test method for small punching, and to achieve the high temperature performance of small punching in an atmosphere environment, the present invention provides a bidirectional loading small punching fixture, which is composed of an upper die, a lower die, an upper punch, a lower punch, a pressure block, a cushion block, a support body and a small punching sample:

[0007] The upper punch is connected by internal threads of the upper die and moves in the through holes of the pressing block, the cushion block and the support body;

[0008] The lower punch is connected by internal threads of the lower die and moves in the through hole of the lower die;

[0009] Upper and lower punches are used for bidirectional loading of small punching specimens.

[0010] Preferably, a vent hole is provided inside the cavity of the lower mold and connected to the gas delivery pipe;

[0011] The gas delivery pipe is connected to the gas cylinder through the gas control valve and the pressure gauge. The gas cylinder is used to store the gas medium required for the atmosphere. The gas control valve and the pressure gauge are used to control the pressure of the atmosphere during the test.

[0012] Preferably, the gas delivery pipe is also connected to the vent hole in the heating furnace, and the heating furnace is used to heat the small punching sample.

[0013] Preferably, the heating furnace is also embedded in the sealed box;

[0014] The sealing box is also embedded with a bidirectional loading small punching fixture.

[0015] The present invention provides a small-damage punching creep fatigue testing device, which is composed of a bidirectional loading small-punching fixture, a bidirectional loading system, a bidirectional strain measurement system and an overall system:

[0016] The overall system is used to control the heating furnace to heat the small punching specimen; it is used to control the bidirectional loading system to implement bidirectional loading on the bidirectional loading small punching fixture, and to collect data on the creep fatigue conditions of the small punching specimen in the bidirectional loading small punching fixture during bidirectional loading through the bidirectional strain measurement system; at the same time, it controls the gas control valve and pressure gauge to adjust the atmosphere pressure during the test.

[0017] Preferably, the bidirectional loading system is composed of an upper rod motor and a lower rod motor, which are used to load the upper punch rod and the lower punch rod respectively according to the control instructions of the overall system to achieve creep fatigue bidirectional testing of small punching specimens.

[0018] Preferably, the bidirectional strain measurement system is composed of an upper extensometer and a lower extensometer; the upper extensometer and the lower extensometer are connected to the upper punch rod and the lower punch rod through bolts to test the displacement of the upper punch rod and the lower punch rod.

[0019] Preferably, the size of the small punching sample is 5 mm in radius and 0.5 mm in thickness; it is arranged in the groove of the support body and fixed by a pad.

[0020] Preferably, the overall system controls the upper rod motor and the lower rod motor to load the upper punch rod and the lower punch rod synchronously or asynchronously.

[0021] Preferably, the bidirectional test method for small punching creep fatigue in an atmosphere environment performed by the device comprises the following steps:

[0022] In the first step, the pre-treated small punching sample is placed between the cushion block and the support body, and the pressing block, the upper die and the lower die are tightened;

[0023] The second step is to control the gas atmosphere of the small punching sample in the sealed box through the gas delivery pipe and gas cylinder;

[0024] The third step is to heat the small punched specimen in a sealed box in a heating furnace to the set test temperature;

[0025] The fourth step is to use the bidirectional loading system to conduct creep, fatigue, and creep fatigue bidirectional loading tests on small punching specimens;

[0026] In the fifth step, the creep fatigue bidirectional strain of the small punching specimen is measured by the upper extensometer and the lower extensometer, and the test data is recorded in the total system.

[0027] The present invention discloses the following technical effects:

[0028] The present invention has the characteristics of high precision, high stability and high reliability, and can be widely used in creep fatigue performance evaluation of various materials, providing strong support for material research and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 is a schematic diagram of the structure of the testing equipment of the present invention;

[0031] Figure 2 : is a schematic diagram of the structure of the bidirectional loading small punching fixture of the present invention, wherein:

[0032] 1 is a gas control valve and a pressure gauge, 2 is a gas cylinder, 3 is a gas delivery pipe, 4 is an upper punch, 5 is an upper die, 6 is a pressure block, 7 is a cushion block, 8 is a specimen, 9 is a support, 10 is a lower die, 11 is a sealing box, 12 is a heating furnace, 13 is a lower punch; 14 is an upper rod motor, 15 is an upper extensometer, 16 is a total system, 17 is a lower extensometer, and 18 is a lower rod motor. DETAILED DESCRIPTION

[0033] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0034] like Figure 1-2 As shown, the present invention provides a small punching test device for realizing creep, fatigue, and creep fatigue bidirectional loading, that is, a damaged small punching creep fatigue test device, which is used to evaluate the high temperature creep performance of materials, and is composed of a bidirectional loading small punching fixture, a bidirectional loading system, a bidirectional strain measurement system and a total system 16;

[0035] A bidirectional loading small punching fixture comprises an upper die 5, a lower die 10, an upper punch rod 4, a lower punch rod 13, a pressing block 6, a cushion block 7, a support body 9, and a small punching sample 8;

[0036] The upper die 5 and the lower die 10 are connected to the testing machine. The upper punch 4 is connected through the internal threads of the upper die 5 and moves in the through holes of the pressure block 6, the cushion block 7 and the support body 9. The lower punch 13 is connected through the internal threads of the lower die 10 and moves in the through holes of the lower die 10. A vent is provided inside the cavity of the lower die 10 and connected to the gas delivery pipe 3; the gas delivery pipe 3 and the gas cylinder 2 are used to store the gas medium required for the atmosphere. The gas control valve and the pressure gauge 1 are used to control the pressure of the atmosphere during the test. The gas delivery pipe 3 is connected to the vent in the heating furnace 12;

[0037] The bidirectional loading system includes an upper punch 4 , a lower punch 13 , an upper punch motor 14 and a lower punch motor 18 .

[0038] The bidirectional strain measurement system includes an upper punch rod 4, a lower punch rod 13, an upper extensometer 15 and a lower extensometer 17. The upper extensometer 15 and the lower extensometer 17 are connected to the upper punch rod 4 and the lower punch rod 13 by bolts and are used to test the displacement of the upper punch rod 4 and the lower punch rod 13.

[0039] The upper punch 4 and the lower punch 13 are used to perform bidirectional loading on the small punching sample 8;

[0040] Under the control of the overall system 16 , the upper punch 4 and the lower punch 13 are loaded respectively by the upper rod motor 14 and the lower rod motor 18 , thereby realizing creep, fatigue, and creep fatigue bidirectional tests on the small punching sample 8 .

[0041] The size of the small punching sample 8 is a radius of 5 mm and a thickness of 0.5 mm. The displacements of the upper punch 4 and the lower punch 13 are measured by an upper extensometer 15 and a lower extensometer 17 connected to the upper punch 4 and the lower punch 13, and are controlled by the overall system 16 to extract, calculate and store the data and strain results of the small punching sample 8.

[0042] The small punched sample 8 contained in the sealed box 11 is heated in the heating furnace 12 under the control of the overall system 16.

[0043] The present invention also provides a testing method for obtaining a small punching creep fatigue bidirectional testing system in an atmosphere environment, which is implemented by the above-mentioned testing device and includes the following specific steps:

[0044] In the first step, the pre-treated small punching sample 5 is placed between the cushion block 7 and the support body 9, and then the pressing block 6, the upper die 5 and the lower die 10 are tightened.

[0045] In the second step, the gas atmosphere of the small punched sample 8 in the sealed box 11 is controlled through the gas delivery pipe 3 and the gas cylinder 2.

[0046] The third step is to heat the small punched sample 8 in the sealed box 11 in a heating furnace 12 to a set test temperature.

[0047] The fourth step is to use the bidirectional loading system to carry out creep, fatigue and creep fatigue bidirectional loading tests on the small punching sample 8.

[0048] In the fifth step, the creep, fatigue and creep fatigue bidirectional strains of the small punching specimen 8 are measured by the upper extensometer 15 and the lower extensometer 17 , and the test data are recorded in the overall system 16 .

[0049] The present invention obtains the strain of the small punching specimen under the atmospheric environment by damaging the small punching creep fatigue testing equipment, which meets the need of comprehensively understanding the creep, fatigue, and creep fatigue bidirectional deformation behaviors of the small punching specimen under the atmospheric environment. It has the characteristics of high precision, high stability and high reliability, and can be widely used in the creep fatigue performance evaluation of various materials, providing strong support for material research and application.

[0050] The present invention is described with reference to flowcharts and / or block diagrams of methods, device systems, and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the process in the flowchart. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0051] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0052] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A bidirectional loading small punching fixture, characterized in that: It is composed of an upper die (5), a lower die (10), an upper punch (4), a lower punch (13), a pressure block (6), a cushion block (7), a support body (9) and a small punching sample (8): The upper punch (4) is connected through the internal thread of the upper die (5) and moves in the through holes of the pressing block (6), the cushion block (7) and the support body (9); The lower punch (13) is connected through the internal thread of the lower die (10) and moves in the through hole of the lower die (10); The upper punch (4) and the lower punch (13) are used to perform bidirectional loading on the small punching sample (8).

2. According to claim 1, a bidirectional loading small punching fixture is characterized in that: The cavity of the lower mold (10) is also provided with a vent hole connected to the gas delivery pipe (3); The gas delivery pipe (3) is connected to the gas cylinder (2) via a gas control valve and a pressure gauge (1); the gas cylinder (2) is used to store the gas medium required for the atmosphere; and the gas control valve and the pressure gauge (1) are used to control the pressure of the atmosphere during the test.

3. According to claim 2, a bidirectional loading small punching fixture is characterized in that: The gas delivery pipe (3) is also connected to a vent hole in a heating furnace (12), and the heating furnace (12) is used to heat the small punching sample (8).

4. According to claim 3, a bidirectional loading small punching fixture is characterized in that: The heating furnace (12) is also embedded in the sealing box (11); The sealing box (11) is also embedded with a bidirectional loading small punching fixture.

5. A small damage punching creep fatigue testing device, characterized in that: The invention is composed of a bidirectional loading small punching fixture, a bidirectional loading system, a bidirectional strain measurement system and an overall system (16) as claimed in any one of claims 1 to 4: The overall system (16) is used to control the heating furnace (12) to heat the small punching sample (8); to control the bidirectional loading system to implement bidirectional loading on the bidirectional loading small punching fixture, and to collect data on the creep fatigue condition of the small punching sample (8) in the bidirectional loading small punching fixture during bidirectional loading through the bidirectional strain measurement system; and to control the gas control valve and the pressure gauge (1) to adjust the atmospheric pressure during the test.

6. The small damage punching creep fatigue testing device according to claim 5, characterized in that: The bidirectional loading system is composed of an upper rod motor (14) and a lower rod motor (18), and is used to load the upper punch rod (4) and the lower punch rod (13) respectively according to the control instructions of the overall system (16), so as to realize the creep fatigue bidirectional test of the small punching sample (8).

7. The small damage punching creep fatigue testing device according to claim 6, characterized in that: The bidirectional strain measurement system is composed of an upper extensometer (15) and a lower extensometer (17); the upper extensometer (15) and the lower extensometer (17) are connected to an upper punch (4) and a lower punch (13) by bolts, and are used to test the displacement of the upper punch (4) and the lower punch (13).

8. The small damage punching creep fatigue testing device according to claim 7, characterized in that: The small punching sample (8) has a size of 5 mm in radius and 0.5 mm in thickness; it is arranged in the groove of the support body (9) and fixed by the cushion block (7).

9. The small damage punching creep fatigue testing device according to claim 8, characterized in that: The overall system (16) controls the upper rod motor (14) and the lower rod motor (18) to load the upper punch rod (4) and the lower punch rod (13) synchronously or asynchronously.

10. A small damage punching creep fatigue testing device according to any one of claims 5 to 9, characterized in that: The bidirectional test method for creep fatigue of small punching holes in an atmosphere environment performed by the device includes the following steps: The first step is to place the pre-treated small punching sample (5) between the cushion block (7) and the support body (9), and then tighten the pressing block (6), the upper die (5) and the lower die (10); The second step is to control the gas atmosphere of the small punched sample (8) in the sealed box (11) through the gas delivery pipe (3) and the gas cylinder (2); The third step is to heat the small punched sample (8) in the sealed box (11) in a heating furnace (12) to a set test temperature; The fourth step is to use a bidirectional loading system to perform creep, fatigue, and creep fatigue bidirectional loading tests on the small punching specimen (8); In the fifth step, the creep fatigue bidirectional strain of the small punching specimen (8) is measured by the upper extensometer (15) and the lower extensometer (17), and the test data is recorded in the overall system (16).

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