A medium strain rate high temperature tensile test device and method

Abstract

The present application belongs to the technical field of engineering materials, structural deformation and mechanical experiments, and particularly relates to a medium strain rate high temperature tensile test device and method. The medium strain rate high temperature tensile test device of the present application can meet the tensile test requirements of materials in a medium strain rate range under a high temperature environment. The upper pull head of the test piece is designed as an arc-shaped flange structure, and is connected to the loading beam using a pin. In this way, the upper pull head of the test piece with an arc-shaped flange is always in a vertical posture under the action of gravity, ensuring the coaxiality of the test piece when it is connected to the upper pull head of the test piece and the lower pull rod of the test piece. Two sets of high temperature heating modules are designed, with the maximum heating temperatures of 800°C and 1400°C respectively. The support frame of the high temperature heating module is designed as an upper and lower adjustable height bracket, which can meet the heating requirements of different test pieces and different fixtures during the test process, thereby improving the operability of the experimental process.

Description

Technical Field

[0001] The present application belongs to the technical field of engineering materials, structural deformation and mechanical experiments, and particularly relates to a medium strain rate and high temperature tensile test device and method. Background Art

[0002] The actual operating environment of aircraft engines is extremely harsh. The turbine inlet temperature of current advanced aircraft engines can reach over 1000°C. To ensure the normal operation and safety of aircraft engines in high-temperature environments, it is first necessary to obtain the dynamic mechanical properties of engine thermal structural materials in high-temperature environments and analyze the dynamic mechanical behavior and failure mechanisms of high-temperature thermal structural materials in high-temperature service environments.

[0003] At present, the research on the dynamic mechanical properties of materials in high-temperature environments mainly focuses on the quasi-static and high strain rate ranges, while there is less research on the dynamic mechanical properties of materials under low and medium strain rates. The material constitutive model obtained in this way is not complete and accurate, and cannot cover the dynamic mechanical properties of materials in the full range from quasi-static to high strain rates under high-temperature environments.

[0004] Therefore, it is necessary to develop a new medium-strain rate and high-temperature tensile test device and method to solve the defects of the existing technology, which plays a vital role in improving the integrity and rationality of the material constitutive model. Summary of the Invention

[0005] The purpose of this application is to provide a medium strain rate and high temperature tensile test device and method to solve at least one problem existing in the prior art.

[0006] The technical solution of this application is:

[0007] A first aspect of the present application provides a medium strain rate and high temperature tensile test apparatus, comprising:

[0008] The loading module includes a loading beam, a force sensor testing machine table and a hydraulic control unit, wherein:

[0009] The loading beam is connected to the hydraulic control unit of the tensile testing machine;

[0010] The force sensor is fixedly mounted on the testing machine table, and the force sensor is located directly below the loading beam;

[0011] The test piece holding module includes a test piece upper pull head, a bolt matching the upper pull head and the test piece, a test piece, a lower pull rod and the test piece matching bolts, a test piece lower pull rod and a shoulder clamp, wherein:

[0012] The upper end of the upper pull head of the test piece is connected to the loading beam through a pin, and the lower end is connected to the upper end of the test piece through the upper pull head and the test piece matching bolts;

[0013] The lower end of the lower tie rod of the test piece is connected to the force sensor through the shoulder fixture, and the upper end is connected to the lower end of the test piece through the lower tie rod and the test piece matching bolts;

[0014] The high-temperature heating module includes a split-type high-temperature furnace shell, a heating element, an adjustable-height furnace support, and a thermocouple.

[0015] The height-adjustable furnace body bracket is provided with a bracket mounting hole, which is fixedly mounted on the test machine table by fasteners;

[0016] The split high-temperature furnace shell is placed on the height-adjustable furnace body support, and a furnace body opening is formed on the split high-temperature furnace shell extending vertically therethrough, and the test piece is placed in a furnace chamber inside the split high-temperature furnace shell through the furnace body opening;

[0017] The heating element is arranged in the furnace and is used to heat the test piece;

[0018] The thermocouple is installed on the shell of the split-type high-temperature furnace.

[0019] In at least one embodiment of the present application, a curved flange is provided at the lower end of the slider on the test piece, and the slider on the test piece can be kept vertical under the action of gravity of the curved flange.

[0020] In at least one embodiment of the present application, the test piece has a gauge section and clamping sections at both ends of the gauge section. By designing the length of the gauge section of the test piece, the clamping section of the test piece is not in the furnace of the split-type high-temperature furnace shell.

[0021] In at least one embodiment of the present application, the shell of the split-type high-temperature furnace is made of 304 stainless steel, and the inner wall surface of the shell of the split-type high-temperature furnace is paved with a polycrystalline mullite fiber layer integrally formed by vacuum casting.

[0022] In at least one embodiment of the present application, the split-type high-temperature furnace shell includes two furnace body split parts, and the two furnace body split parts are connected by a buckle.

[0023] In at least one embodiment of the present application, an observation port is provided in the middle of the shell of the split-type high-temperature furnace, and a quartz glass observation window is installed at the observation port.

[0024] In at least one embodiment of the present application,

[0025] When the experimental high-temperature heating requirement is in the range of 0°C to 1400°C, the heating element adopts a silicon carbon rod and the thermocouple adopts a B-type thermocouple.

[0026] When the experimental high-temperature heating requirement is in the range of 0°C to 800°C, the heating element adopts an alloy wire made of 0Cr27Al7Mo2, and the thermocouple adopts an S-type thermocouple.

[0027] In at least one embodiment of the present application, a water cooling channel is provided on the shoulder clamp, and the water cooling channel is connected to the water inlet and return module.

[0028] In at least one embodiment of the present application, a radiation heat shield is installed on the shoulder fixture.

[0029] A second aspect of the present application provides a medium strain rate and high temperature tensile test method, based on the medium strain rate and high temperature tensile test apparatus described above, comprising:

[0030] Complete the loading module construction;

[0031] Select the heating element and thermocouple according to the high-temperature heating requirements of the experiment, and complete the construction of the high-temperature heating module;

[0032] The test piece support module is built, including:

[0033] Connect the shoulder fixture to the force sensor, and connect the lower pull rod of the test piece to the shoulder fixture;

[0034] Pass the test piece through the furnace opening and connect the test piece to the lower tie rod of the test piece through the matching bolts of the lower tie rod and the test piece;

[0035] Connect the upper pull head of the test piece to the loading beam through a pin;

[0036] After adjusting the height of the loading beam, connect the upper pull head of the test piece to the test piece through the matching bolts of the upper pull head and the test piece;

[0037] Temperature loading is performed through a high-temperature heating module, and load loading is performed through a hydraulic control unit of the tensile testing machine.

[0038] The invention has at least the following beneficial technical effects:

[0039] The medium strain rate and high temperature tensile test apparatus of the present application can realize high temperature tensile test research of different materials in the medium strain rate range, which is used to calibrate the material constitutive model, thereby improving the integrity and rationality of the material constitutive model. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 Schematic diagram of a medium strain rate and high temperature tensile test apparatus according to one embodiment of the present application;

[0041] Figure 2 This is a schematic diagram of a high-temperature heating module according to one embodiment of the present application;

[0042] Figure 3 It is a schematic diagram of a test piece according to one embodiment of the present application.

[0043] in:

[0044] 11-Loading beam; 12-Force sensor; 13-Testing machine table; 14-Hydraulic control unit; 21-Upper pull head of test piece; 22-Matching bolts between upper pull head and test piece; 23-Test piece; 24-Matching bolts between lower pull rod and test piece; 25-Lower pull rod of test piece; 26-Shoulder clamp; 31-Observation port; 32-Split high-temperature furnace shell; 33-Furnace chamber; 34-Heating element; 35-Adjustable height furnace bracket; 36-Water inlet and return module; 37-Radiation insulation board; 38-Thermocouple; 39-Bracket mounting hole; 310-Furnace opening; 311-Furnace split part; 312-Quartz glass observation window. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below in conjunction with the drawings in the embodiments of this application. In the drawings, the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The described embodiments are part of the embodiments of this application, not all of the embodiments. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain this application, and should not be understood as limitations on this application. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. The embodiments of this application are described in detail below in conjunction with the drawings.

[0046] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be understood as limiting the scope of protection of this application.

[0047] The following is combined with Figures 1 to 3 This application is described in further detail.

[0048] A first aspect of the present application provides a medium strain rate and high temperature tensile test device, comprising: a loading module, a test piece holding module, and a high temperature heating module.

[0049] Specifically, such as Figure 1 As shown, the loading module includes a loading beam 11, a force sensor 12, a test machine table 13 and a hydraulic control unit 14, wherein the loading beam 11 is connected to the hydraulic control unit 14 of the tensile testing machine, and can load the test piece 23 under the control of the hydraulic control unit 14. The loading beam 11 can be configured with multiple limiting structures so that the loading beam 11 can only be loaded in the vertical direction; the force sensor 12 is fixedly installed on the test machine table 13, and the force sensor 12 is located directly below the loading beam 11.

[0050] The test piece holding module includes a test piece upper pull head 21, a bolt 22 for matching the upper pull head and the test piece, a test piece 23, a lower pull rod 24 for matching the test piece, a test piece lower pull rod 25 and a shoulder clamp 26, wherein the upper end of the test piece upper pull head 21 is connected to the loading beam 11 through a pin, and the lower end is connected to the upper end of the test piece 23 through the bolt 22 for matching the upper pull head and the test piece; the lower end of the test piece lower pull rod 25 is connected to the force sensor 12 through the shoulder clamp 26, and the upper end is connected to the lower end of the test piece 23 through the bolt 24 for matching the lower pull rod and the test piece.

[0051] In a preferred embodiment of the present application, a curved flange is provided at the lower end of the test piece upper pull head 21. The curved flange maintains the test piece upper pull head 21 in an upright position due to gravity. This specially designed curved flange ensures that the test piece upper pull head 21 remains upright under the action of gravity, thereby ensuring the coaxiality of the test piece 23 when installed with the test piece upper pull head 21 and the test piece lower pull rod 25, thereby improving the accuracy of the test.

[0052] In a preferred embodiment of the present application, Figure 3 As shown, the gauge section of the test piece 23 is designed to be longer. This design ensures that the clamping section of the test piece 23 is not in the furnace 33 of the split high-temperature furnace shell 32, ensuring that the temperature of the clamping end is not too high, thereby improving the accuracy of the experimental results.

[0053] The high-temperature heating module includes a split-type high-temperature furnace shell 32, a heating element 34, an adjustable-height furnace body bracket 35, and a thermocouple 38, wherein the adjustable-height furnace body bracket 35 is provided with a bracket mounting hole 39, which is fixedly mounted on the test machine table 13 by fasteners; the split-type high-temperature furnace shell 32 is placed on the adjustable-height furnace body bracket 35, and the split-type high-temperature furnace shell 32 is provided with a furnace body opening 310 that passes through the top and bottom, and the test piece 23 is set in the furnace chamber 33 inside the split-type high-temperature furnace shell 32 through the furnace body opening 310; the heating element 34 is set in the furnace chamber 33 for heating the test piece 23; the thermocouple 38 is installed on the split-type high-temperature furnace shell 32.

[0054] In a preferred embodiment of the present application, the split high-temperature furnace shell 32 is made of 304 stainless steel, and the inner wall surface of the split high-temperature furnace shell 32 is paved with a vacuum-cast integrally formed polycrystalline mullite fiber layer.

[0055] In a preferred embodiment of the present application, the split-type high-temperature furnace shell 32 is placed on an adjustable-height furnace body bracket 35. The split-type high-temperature furnace shell 32 includes two furnace body split parts 311, which are split left and right. The two furnace body split parts 311 are opened and closed by buckles. When the left and right furnace body split parts 311 are opened to the maximum position, the sample loading space is 120 mm wide.

[0056] In a preferred embodiment of the present application, a 30×80 mm observation port 31 is provided in the middle of the split high-temperature furnace shell 32 , and a quartz glass observation window 312 is installed at the observation port 31 , which can be opened sideways for observing the loading state of the test piece 23 .

[0057] The medium strain rate high temperature tensile test device of the present application can select different high temperature heating modules for different experimental high temperature heating requirements. For example, when the experimental high temperature heating requirement is in the range of 0℃~1400℃, the heating element 34 adopts a new process silicon carbon rod, one is installed on each side of the left and right sides of the test piece 23, and the thermocouple 38 adopts a B-type thermocouple. When the experimental high temperature heating requirement is in the range of 0℃~800℃, the heating element 34 adopts a high temperature electric heating alloy wire made of 0Cr27Al7Mo2, which is heated on all four sides. The heating wire is inlaid with the inner wall surface of the split high temperature furnace shell 32 as an integral part, and the thermocouple 38 adopts an S-type thermocouple. The observation port 31 and external dimensions of the two high temperature heating modules are consistent, and the adjustable height furnace bracket 35 can be shared.

[0058] Advantageously, in this embodiment, a water cooling channel is provided on the shoulder fixture 26 and connected to the water inlet and return module 36, enabling rapid heat dissipation and temperature reduction. Furthermore, a radiation heat shield 37 is mounted on the shoulder fixture 26 to largely protect the force sensor 12 from temperature influences, ensuring more accurate and reliable experimental results.

[0059] The medium strain rate and high temperature tensile test device of the present application can meet the requirements of medium strain rate tensile testing of materials in high temperature environments. The upper pull head 21 of the test piece is designed as an arc-shaped flange structure and is connected to the loading beam 11 using a pin. This allows the upper pull head 21 of the test piece with an arc-shaped flange to always be in a vertical position under the action of gravity, ensuring the coaxiality of the test piece 23 when connected to the upper pull head 21 of the test piece and the lower pull rod 25 of the test piece. Two sets of high temperature heating modules are designed, with maximum heating temperatures of 800℃ and 1400℃ respectively. The 800℃ high temperature heating module can meet the high temperature heating requirements of materials in the range of 0℃ to 800℃, and the temperature value reached by heating is relatively accurate; the 1400℃ high temperature heating module can meet the high temperature heating requirements of materials in the range of 0℃ to 1400℃, and the temperature value reached by heating in the range of 800℃ to 1400℃ is relatively accurate. The support frame of the high-temperature heating module is designed as an adjustable height bracket, which can meet the heating requirements of different test pieces 23 and different fixtures during the test, improving the operability of the experimental process.

[0060] Based on the above-mentioned medium strain rate and high temperature tensile test apparatus, the second aspect of the present application provides a medium strain rate and high temperature tensile test method, including:

[0061] Complete the loading module construction;

[0062] According to the high-temperature heating requirements of the experiment, the heating element 34 and the thermocouple 38 are selected to complete the high-temperature heating module.

[0063] The test piece support module is built, including:

[0064] Connect the shoulder fixture 26 to the force sensor 12, and connect the test piece lower pull rod 25 to the shoulder fixture 26;

[0065] Pass the test piece 23 through the furnace opening 310 and connect the test piece 23 to the test piece lower tie rod 25 through the lower tie rod and the test piece matching bolts 24;

[0066] The upper pull head 21 of the test piece is fixed to the loading beam 11 by means of a latch;

[0067] After adjusting the height of the loading beam 11, connect the upper pull head 21 of the test piece to the test piece 23 through the upper pull head and the test piece matching bolts 22;

[0068] Temperature loading is performed by a high-temperature heating module, and load loading is performed by a hydraulic control unit 14 of the tensile testing machine.

[0069] The medium strain rate and high temperature tensile test method of the present application can meet the tensile test requirements of different materials under medium strain rate and high temperature environments. The experiment has strong operability, high efficiency and high credibility of the experimental results.

[0070] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A medium strain rate high temperature tensile test device, characterized in that: include: A loading module, comprising a loading beam (11), a force sensor (12), a test machine table (13) and a hydraulic control unit (14), wherein: The loading beam (11) is connected to the hydraulic control unit (14) of the tensile testing machine; The force sensor (12) is fixedly mounted on the testing machine table (13), and the force sensor (12) is located directly below the loading beam (11); A test piece holding module, comprising a test piece upper pull head (21), a bolt (22) for matching the upper pull head and the test piece, a test piece (23), a lower pull rod and a bolt (24) for matching the test piece, a test piece lower pull rod (25), and a shoulder clamp (26), wherein: The upper end of the test piece upper pull head (21) is connected to the loading beam (11) through a latch, and the lower end is connected to the upper end of the test piece (23) through a bolt (22) that matches the upper pull head and the test piece; The lower end of the test piece lower pull rod (25) is connected to the force sensor (12) through the shoulder clamp (26), and the upper end is connected to the lower end of the test piece (23) through the lower pull rod and the test piece matching bolt (24); A high-temperature heating module, comprising a split-type high-temperature furnace shell (32), a heating element (34), a height-adjustable furnace support (35), and a thermocouple (38), wherein: The height-adjustable furnace support (35) is provided with a support mounting hole (39) and is fixedly mounted on the test machine table (13) via fasteners; The split high-temperature furnace shell (32) is placed on the height-adjustable furnace support (35); a furnace opening (310) is provided on the split high-temperature furnace shell (32) and passes through the furnace opening (310); and the test piece (23) is placed in a furnace chamber (33) inside the split high-temperature furnace shell (32); The heating element (34) is arranged in the furnace (33) and is used to heat the test piece (23); The thermocouple (38) is installed on the split high-temperature furnace shell (32).

2. The medium strain rate and high temperature tensile test device according to claim 1, characterized in that: The lower end of the test piece upper slider (21) is provided with an arc-shaped flange, and the test piece upper slider (21) can be kept vertical under the action of the gravity of the arc-shaped flange.

3. The medium strain rate and high temperature tensile test device according to claim 2, characterized in that: The test piece (23) has a gauge section and clamping sections at both ends of the gauge section. By designing the length of the gauge section of the test piece (23), the clamping section of the test piece (23) is not in the furnace (33) of the split high-temperature furnace shell (32).

4. The medium strain rate and high temperature tensile test device according to claim 1, characterized in that: The split high-temperature furnace shell (32) is made of 304 stainless steel, and the inner wall surface of the split high-temperature furnace shell (32) is paved with a polycrystalline mullite fiber layer formed integrally by vacuum casting.

5. The medium strain rate and high temperature tensile test device according to claim 4, characterized in that: The split-type high-temperature furnace shell (32) comprises two furnace body split parts (311), and the two furnace body split parts (311) are connected by a buckle.

6. The medium strain rate and high temperature tensile test device according to claim 5, characterized in that: An observation port (31) is provided in the middle of the split-type high-temperature furnace shell (32), and a quartz glass observation window (312) is installed at the observation port (31).

7. The medium strain rate and high temperature tensile test device according to claim 6, characterized in that: When the experimental high temperature heating requirement is in the range of 0°C to 1400°C, the heating element (34) adopts a silicon carbon rod, and the thermocouple (38) adopts a B-type thermocouple; When the experimental high-temperature heating requirement is in the range of 0°C to 800°C, the heating element (34) adopts an alloy wire made of 0Cr27Al7Mo2, and the thermocouple (38) adopts an S-type thermocouple.

8. The medium strain rate and high temperature tensile test device according to claim 7, characterized in that: A water cooling channel is provided on the shoulder clamp (26), and the water cooling channel is connected to the water inlet and return module (36).

9. The medium strain rate and high temperature tensile test device according to claim 8, characterized in that: A radiation heat insulation board (37) is installed on the shoulder fixture (26).

10. A medium strain rate and high temperature tensile test method, based on the medium strain rate and high temperature tensile test device according to any one of claims 1 to 9, characterized in that: include: Complete the loading module construction; According to the experimental high-temperature heating requirements, a heating element (34) and a thermocouple (38) are selected to complete the high-temperature heating module; The test piece support module is built, including: Connecting the shoulder fixture (26) to the force sensor (12), and connecting the test piece lower pull rod (25) to the shoulder fixture (26); Pass the test piece (23) through the furnace body opening (310), and connect the test piece (23) to the test piece lower pull rod (25) through the lower pull rod and the test piece matching bolts (24); Connecting the upper pull head (21) of the test piece to the loading beam (11) via a latch; After adjusting the height of the loading beam (11), the upper pull head (21) of the test piece is connected to the test piece (23) through the upper pull head and the test piece matching bolts (22); Temperature loading is performed through a high-temperature heating module, and load loading is performed through a hydraulic control unit (14) of a tensile testing machine.

Images