Medium-strain-rate high-temperature tensile experiment device and method

Abstract

The invention belongs to the technical field of engineering materials, structural deformation and mechanical experiments, and particularly relates to a medium-strain-rate high-temperature tensile experiment device and method. The medium-strain-rate high-temperature tensile test device can meet the tensile test requirement of a material in a medium-strain-rate range in a high-temperature environment. The upper pull head of the test piece is designed into an arc-shaped flange structure and is connected with the loading cross beam through a bolt, so that the upper pull head of the test piece with the arc-shaped flange is always in a vertical posture under the action of gravity, and the coaxiality when the test piece is connected with the upper pull head of the test piece and the lower pull rod of the test piece is ensured. Two sets of high-temperature heating modules are designed, and the highest heating temperatures are 800 DEG C and 1400 DEG C respectively. The supporting frame of the high-temperature heating module is designed to be a support with the height capable of being adjusted up and down, the heating requirements of different test pieces and different clamps in the test process can be met, and the operability of the test process is improved.

Description

Technical Field

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

[0002] The actual working environment of aircraft engines is very harsh. The turbine inlet temperature of current advanced aircraft engines can reach over 1000°C. In order 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 structure materials in high-temperature environments and analyze the dynamic mechanical behavior and failure mechanism of high-temperature thermal structure materials in high-temperature service environments.

[0003] At present, the research on the dynamic mechanical properties of materials under high temperature environment is mainly concentrated in the quasi-static and high strain rate ranges, while there are fewer studies on the dynamic mechanical properties of materials under low strain rate and medium strain rate. 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 rate under high temperature environment.

[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 the present application is to provide a medium strain rate 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] The first aspect of the present application provides a medium strain rate high temperature tensile test device, comprising:

[0008] A loading module, 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 test 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 latch, 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 pull 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 pull rod and the test piece matching bolts;

[0014] A high temperature heating module, comprising a split high temperature furnace shell, a heating element, an adjustable height furnace support, and a thermocouple, wherein:

[0015] The height-adjustable furnace body bracket is provided with a bracket mounting hole, and 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 provided 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 disposed 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 shell of the split-type high-temperature furnace includes two split furnace body parts, and the two split furnace body 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 is a silicon carbon rod and the thermocouple is a type B 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 insulation board is installed on the shoulder clamp.

[0029] The second aspect of the present application provides a medium strain rate high temperature tensile test method, based on the medium strain rate high temperature tensile test device as 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 latch;

[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 high temperature tensile test device 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 It is a schematic diagram of a medium strain rate high temperature tensile test device according to one embodiment of the present application;

[0041] Figure 2 is a schematic diagram of a high temperature heating module according to an 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-test machine table; 14-hydraulic control unit; 21-pull head on the test piece; 22-matching bolts between the pull head and the test piece; 23-test piece; 24-matching bolts between the lower pull rod and the test piece; 25-lower pull rod of the test piece; 26-shoulder clamp; 31-observation port; 32-open 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-opening of the furnace body; 312-quartz glass observation window. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical scheme and advantages of the implementation of this application clearer, the technical scheme in the embodiment of this application will be described in more detail below in conjunction with the drawings in the embodiment 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 them. 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 construed 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 the present application, it should be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present 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, and therefore should not be understood as limiting the scope of protection of the present 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 high temperature tensile test device, comprising: a loading module, a test piece holding module and a high temperature heating module.

[0049] Specifically, 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, and can be configured with a variety of limiting structures for the loading beam 11 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, an upper pull head and a test piece matching bolt 22, a test piece 23, a lower pull rod and a test piece matching bolt 24, 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 upper pull head and the test piece matching bolt 22; 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.

[0051] In the preferred embodiment of the present application, the lower end of the upper pull head 21 of the test piece is provided with an arc-shaped flange, which can keep the upper pull head 21 of the test piece vertical under the action of gravity. The specially designed arc-shaped flange can ensure that the upper pull head 21 of the test piece is kept vertical under the action of gravity, thereby ensuring the coaxiality of the test piece 23 when the test piece 23 is installed with the upper pull head 21 of the test piece and the lower pull rod 25 of the test piece, thereby improving the accuracy of the experiment.

[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. Through such a design, 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, and 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 runs through the split-type high-temperature furnace shell 32 from top to 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, and is used to heat 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 shell 32 of the split-type high-temperature furnace is made of 304 stainless steel, and the inner wall surface of the shell 32 of the split-type high-temperature furnace is paved with a polycrystalline mullite fiber layer integrally formed by vacuum casting.

[0055] In a preferred embodiment of the present application, a 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 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 double-open high temperature furnace shell 32 as an integral part, and the thermocouple 38 adopts an S-type thermocouple. The observation port 31 and the 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 the water cooling channel is connected to the water inlet and return module 36, and rapid heat dissipation and cooling can be achieved through the water inlet and return module 36. In addition, a radiation heat insulation board 37 is installed on the shoulder fixture 26, and the radiation heat insulation board 37 can largely protect the force sensor 12 from the influence of temperature, making the experimental results more accurate and reliable.

[0059] The medium strain rate high temperature tensile test device of the present application can meet the requirements of the medium strain rate range tensile test of materials in a high temperature environment. The upper pull head 21 of the test piece is designed as an arc flange structure, and is connected to the loading beam 11 by a latch, so that the upper pull head 21 of the test piece with an arc flange can always be in a vertical posture under the action of gravity, ensuring the coaxiality of the test piece 23 when connected with 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, and the maximum heating temperatures are 800℃ and 1400℃ respectively. The 800℃ high temperature heating module can meet the high temperature heating requirements of the material in the range of 0℃ to 800℃, and the temperature value reached by heating is more accurate; the 1400℃ high temperature heating module can meet the high temperature heating requirements of the material in the range of 0℃ to 1400℃, and the temperature value reached by heating by the 1400℃ high temperature heating module in the range of 800℃ to 1400℃ is more 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 high temperature tensile test device, the second aspect of the present application provides a medium strain rate 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 construction of 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 pull head 21 on 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, 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;

[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 experimental results.

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

Claims

1. A medium strain rate high temperature tensile test device, characterized in that: include: A loading module, the 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, the 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 upper pull head (21) of the test piece 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 with 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, the high-temperature heating module comprising a split-type high-temperature furnace shell (32), a heating element (34), a furnace support with adjustable height (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) by means of 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 runs through the split high-temperature furnace shell (32) from top to bottom; and the test piece (23) is placed in a furnace chamber (33) inside the split high-temperature furnace shell (32) through the furnace opening (310); 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 shell (32) of the split high-temperature furnace.

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

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

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

6. The medium strain rate high temperature tensile test device according to claim 5, characterized in that: An 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).

7. The medium strain rate 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) is a silicon carbon rod, and the thermocouple (38) is 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) is made of alloy wire made of 0Cr27Al7Mo2, and the thermocouple (38) is an S-type thermocouple.

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

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

10. A medium strain rate high temperature tensile test method, based on the medium strain rate 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 high-temperature heating requirements of the experiment, a heating element (34) and a thermocouple (38) are selected to complete the construction of a 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 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); 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 the tensile testing machine.

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