Solid propellant tensile sample transverse vibration test device and method

Abstract

The invention discloses a transverse vibration test device and method for a solid propellant tensile sample. The device comprises a transverse vibration base, a first transverse vibration pressing plate and a second transverse vibration pressing plate, a first groove and a second groove are symmetrically formed in the transverse vibration base in the transverse direction, and a gap is formed between the first groove and the second groove; the first transverse vibration pressing plate is connected to the transverse vibration base and partially embedded into the first groove, and the second transverse vibration pressing plate is connected to the transverse vibration base and partially embedded into the second groove. And a connecting structure is arranged on the transverse vibration base and is used for fixing the transverse vibration base on the electric vibration test bed. The transverse vibration loading device relates to the technical field of vibration tests, is simple in structure and convenient to use, can fill the blank of transverse vibration in a propellant vibration experiment, can meet various requirements of the vibration experiment, can accurately transmit acceleration load, and realizes transverse vibration loading of a solid propellant tensile sample in two directions.

Description

Technical Field

[0001] The invention relates to the technical field of vibration testing, in particular to a device and method for testing a lateral vibration of a solid propellant tensile specimen. Background Art

[0002] Solid propellants are subject to vibration loads at various stages of production, transportation, and storage. Continuous vibration during transportation and storage can cause fatigue damage to solid propellants, which in turn affects the mechanical properties of solid propellants and even causes failure of propellants, seriously affecting the storage and service life of solid propellants. Therefore, it is necessary to carry out vibration tests on solid propellants to study the damage evolution law of solid propellants under vibration loads and provide data support for their structural integrity analysis.

[0003] At present, most solid propellant vibration tests use a fixture to fix the two ends of the dumbbell-shaped specimen, and control the displacement of the fixture to apply periodic stress or strain loads to the propellant. However, in actual engineering, the propellant is more subject to acceleration loads, and the above loading mode cannot fully simulate the actual load conditions. It is necessary to build a new solid propellant vibration test platform and develop a new solid propellant lateral vibration test method to simulate various random vibrations that may occur in actual engineering. In addition, the existing solid propellant axial vibration tests are mostly to provide vibration aging conditions for solid propellant tensile specimens. It is impossible to monitor and record the physical quantities during the vibration process, and it is difficult to conduct theoretical analysis and verification of the lateral vibration of solid propellants.

[0004] Existing vibration test devices are used for vertical vibration loading and shear vibration loading of solid propellant tensile specimens. However, the actual loading form of propellants in engineering is complex, and the stress and strain fields generated in different parts of the propellant are significantly different. In order to study the damage law of different parts of the grain under vibration load, vibration experiments under different loading forms of propellants should be carried out respectively. It is necessary to design a solid propellant lateral vibration test device to fill the gap in this field. Summary of the invention

[0005] In view of the deficiencies in the above-mentioned prior art, the present invention provides a lateral vibration test device and method for a solid propellant tensile specimen, which is not only simple in structure and easy to use, but also can fill the gap in the lateral vibration of propellant vibration experiments, can serve various requirements of vibration experiments, can accurately transmit acceleration loads, realize lateral vibration loading of solid propellant tensile specimens in two directions, and provide an exposed test section for temperature monitoring.

[0006] To achieve the above-mentioned object, the present invention provides a solid propellant tensile specimen lateral vibration test device, comprising a lateral vibration base, a first lateral vibration platen and a second lateral vibration platen;

[0007] The lateral vibration base is symmetrically provided with a first groove and a second groove in the lateral direction, and there is a gap between the first groove and the second groove for embedding two ends of the solid propellant tensile specimen;

[0008] The first transverse vibration platen is detachably connected to the transverse vibration base and partially embedded in the first groove, and the second transverse vibration platen is detachably connected to the transverse vibration base and partially embedded in the second groove;

[0009] The lateral vibration base is provided with a connecting structure for fixing the lateral vibration base on the electric vibration test bench.

[0010] In one embodiment, the connection structure includes a plurality of first threaded holes spaced laterally on the lateral vibration base;

[0011] The axial direction of the first threaded hole is parallel to the vertical direction.

[0012] In one embodiment, the connection structure includes a plurality of second threaded holes spaced laterally on the lateral vibration base;

[0013] The axial direction of the second threaded hole is perpendicular to the vertical direction.

[0014] In one embodiment, a first convex pad is provided on the first transverse vibration platen, and the first convex pad is embedded in the first groove;

[0015] A second convex pad is disposed on the second transverse vibration pressing plate, and the second convex pad is embedded in the second groove.

[0016] To achieve the above object, the present invention also provides a method for a lateral vibration test of a solid propellant tensile specimen, wherein the above device is used to perform a lateral vibration test on a solid propellant tensile specimen;

[0017] The lateral vibration test method includes preparation before the test, a vibration table test, a first electron microscope scan, a uniaxial constant speed tensile test and a second electron microscope scan.

[0018] In one embodiment, the process of preparing before the test is:

[0019] The solid propellant tensile specimen to be tested is labeled, and the original microstructure image of the surface of the test section on the solid propellant tensile specimen is taken using a scanning electron microscope;

[0020] Clean the surface measuring points of the solid propellant tensile specimen and locate them with a marker pen, attach the strain gauges to the surface measuring points of the solid propellant tensile specimen and weld the wires to provide conditions for strain field measurement during the test;

[0021] Assemble the lateral vibration test apparatus and place the solid propellant tensile specimens;

[0022] Adjust the vibration platform of the electric vibration test system to a suitable height, and then fix the lateral vibration test device with the solid propellant tensile specimen placed on it to the vibration platform of the electric vibration test system. When the test starts, the vibration platform performs vertical reciprocating motion under the set acceleration conditions, and the reciprocating motion is transmitted to the solid propellant tensile specimen by the lateral vibration test device to realize the loading of the vibration acceleration load;

[0023] An infrared imager is fixed around the electric vibration test system, with the infrared imager lens facing the temperature monitoring surface. The power cord and network cable of the infrared imager are connected to capture the surface temperature field data of the solid propellant tensile specimen and transmit and store the image data in real time;

[0024] Connect the strain gauge wire to the strain meter to record and store the strain field data during the vibration process in real time.

[0025] In one embodiment, the process of the vibration table test is:

[0026] According to the vibration data collected in actual working conditions, select the waveform, frequency, acceleration amplitude or power spectrum density of the test load in the electric vibration test system, select the vibration monitoring and control channel, and set the vibration time;

[0027] Turn on the power amplifier in the electrodynamic vibration test system, check the test conditions to ensure that the test conditions are set correctly, check the test platform wiring to ensure that all physical quantities can be detected and recorded in real time, and then start the test;

[0028] The lateral vibration test device with the solid propellant tensile specimen placed thereon is fixed to the vibration platform fixed to the electric vibration test system with the first bolt hole, and the first lateral vibration test is carried out, and the surface temperature cloud diagram of the solid propellant tensile specimen at different times during the vibration process is recorded, and the curve of the maximum temperature of the surface of the solid propellant tensile specimen changing with time during the vibration process is recorded, and the curve of the strain changing with time at each surface measuring point is recorded;

[0029] The lateral vibration test device with the solid propellant tensile specimen placed thereon is fixed to the vibration platform fixed to the electric vibration test system through the second bolt hole, and the first lateral vibration test is carried out, and the surface temperature cloud diagram of the solid propellant tensile specimen at different times during the vibration process is recorded, and the curve of the maximum temperature of the surface of the solid propellant tensile specimen changing with time during the vibration process is recorded, and the curve of the strain changing with time at each surface measuring point is recorded;

[0030] The intrinsic relationship between temperature rise and structural damage is analyzed based on the surface temperature distribution cloud diagram of solid propellant tensile specimens;

[0031] The temperature-time curve and the strain-time curve are combined to analyze the mechanism of temperature rise. The maximum temperature and strain at each point on the surface of the solid propellant tensile specimen at different times are compared with the theoretical model to verify the accuracy of the model.

[0032] In one embodiment, the process of the first electron microscope scanning is:

[0033] Select 2 to 4 solid propellant tensile specimens from a group of solid propellant tensile specimens after vibration, and slice the test sections of the selected solid propellant tensile specimens;

[0034] Use a scanning electron microscope to take microscopic structural images of the test section surface after vibration;

[0035] The surface mesostructure image of the solid propellant tensile specimen after vibration is compared with the original mesostructure image before vibration to analyze the effect of vibration load on the propellant mesostructure in actual engineering.

[0036] In one embodiment, the process of the uniaxial constant speed tensile test is:

[0037] Prepare several solid propellant tensile specimens before and after vibration, and measure and record the dimensions of the test section of each solid propellant tensile specimen;

[0038] The unvibrated solid propellant tensile specimen and the vibrated solid propellant tensile specimen were stretched at a stretching rate of 1 to 3 mm / min until they broke, and the force-displacement curve during stretching was recorded;

[0039] Calculate the initial modulus, tensile strength, breaking strength, maximum elongation and elongation at break of each solid propellant tensile specimen;

[0040] By comparing the initial modulus, tensile strength, breaking strength, maximum elongation and breaking elongation of the solid propellant tensile specimens before and after vibration, the degradation law of the mechanical properties of the propellant under vibration conditions was obtained.

[0041] In one embodiment, the process of the second electron microscope scanning is:

[0042] The fracture surface of the solid propellant tensile specimen was sliced ​​and the microstructure image of the fracture surface was taken using a scanning electron microscope.

[0043] The microstructure images of the fracture surface of the solid propellant tensile specimen after vibration are compared with those of the non-vibrated specimen to analyze the effect of vibration aging on the failure mode of the propellant.

[0044] Compared with the prior art, the present invention has the following beneficial technical effects:

[0045] 1. The solid propellant lateral vibration test method of the present invention, with the help of the existing electric vibration test system, can apply vibration acceleration load to the solid propellant tensile specimen through the reciprocating motion of the vibration table plane to simulate the actual working conditions;

[0046] 2. The solid propellant lateral vibration test method of the present invention applies complex alternating stresses through lateral vibration loading, which is different from axial vibration which can only apply alternating normal stresses in the vibration direction, and can simulate the complex stresses and strains in actual working conditions;

[0047] 3. The solid propellant lateral vibration test method of the present invention can monitor the temperature field and strain field of the solid propellant tensile specimen in real time during the vibration process and store the test data with the help of an infrared imager, a strain measurement system, an electron microscope scanning system, an electronic universal testing machine and corresponding software configuration, and can be used for theoretical analysis and verification of the lateral vibration of solid propellants;

[0048] 4. The solid propellant lateral vibration test device of the present invention can fix both ends of the solid propellant standard dumbbell-shaped tensile solid propellant tensile specimen on the vibration test device by assembling the lateral vibration pressure plate and the lateral vibration base. Through the lateral vibration test device, the acceleration load of the electric vibration test system is transferred to the test section of the tensile solid propellant tensile specimen, so that the lateral vibration loading of the solid propellant tensile specimen can be realized;

[0049] 5. The transverse vibration base of the solid propellant transverse vibration test device of the present invention is provided with two groups of threaded holes for fixing the base, and the axes of the two groups of threaded holes are perpendicular to each other. By changing the fixing direction of the transverse vibration test device, the transverse vibration loading of the solid propellant tensile specimen in different directions can be achieved;

[0050] 6. The lateral cross-section of the lateral vibration base on the solid propellant lateral vibration test device of the present invention is L-shaped as a whole, and the lateral vibration pressure plate fixes the two ends of the propellant tensile specimen. The overall structure of the lateral vibration test device does not block the test section of the solid propellant tensile specimen, and an infrared imaging thermometer can be used to monitor the surface temperature of the test section in real time. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] 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 or the description of the prior art 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 the structures shown in these drawings without paying creative work.

[0052] Figure 1It is an axonometric view of a lateral vibration test device (including a solid propellant tensile specimen) in an embodiment of the present invention;

[0053] Figure 2 It is an axonometric view of a transverse vibration base (including a solid propellant tensile specimen) in an embodiment of the present invention;

[0054] Figure 3 is a front view of a lateral vibration base in an embodiment of the present invention;

[0055] Figure 4 is an axonometric view of the first transverse vibration platen in an embodiment of the present invention;

[0056] Figure 5 is an axonometric view of the second transverse vibration platen in an embodiment of the present invention;

[0057] Figure 6 It is a top view of a lateral vibration test device (including a solid propellant tensile specimen) in an embodiment of the present invention;

[0058] Figure 7 It is a front view of the lateral vibration test device (including the solid propellant tensile specimen) in the embodiment of the present invention.

[0059] Reference numerals: lateral vibration base 1, first lateral vibration pressure plate 2, first through hole 201, first convex pad 202, second lateral vibration pressure plate 3, second through hole 301, second convex pad 302, bottom plate 4, first threaded hole 401, second threaded hole 402, side plate 5, first protrusion 6, first groove 601, third threaded hole 602, second protrusion 7, second groove 701, fourth threaded hole 702, solid propellant tensile specimen 8.

[0060] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0061] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0063] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0064] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, a physical connection, or a wireless communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0065] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0066] Example 1

[0067] like Figures 1 to 5 The present embodiment discloses a lateral vibration test device for a solid propellant tensile specimen, which mainly comprises a lateral vibration base 1 , a first lateral vibration platen 2 and a second lateral vibration platen 3 .

[0068] The lateral vibration base 1 is an L-shaped structure as a whole, and is composed of a bottom plate 4 and a side plate 5. Two first protrusions 6 and second protrusions 7 extending upward are symmetrically arranged at the top ends of the side plate 5. The first protrusion 6 is provided with a first groove 601 into which the first end of the solid propellant tensile specimen 8 can be embedded, and the second protrusion 7 is provided with a second groove 701 into which the second end of the solid propellant tensile specimen 8 can be embedded. The first groove 601 and the second groove 701 are symmetrical in the transverse direction, and one side and the opposite end of the first groove 601 and the second groove 701 are both provided with openings.

[0069] At least one third threaded hole 602 is provided on the first convex block 6 at a position around the side opening of the first groove 601, and the first transverse vibration platen 2 is provided with a first through hole 201 corresponding to the third threaded hole 602. During the test, the first transverse vibration platen 2 is detachably connected to the first convex block 6 through the cooperation of the first through hole 201, the third threaded hole 602 and the screw to cover the side opening of the first groove 601.

[0070] As a preferred embodiment, when the first transverse vibration platen 2 covers the side opening of the first groove 601, part of the first transverse vibration platen 2 is embedded in the first groove 601, and then abuts against the side of the first end of the solid propellant tensile specimen 8, thereby ensuring the fixation of the first end of the solid propellant tensile specimen 8. Specifically, the first transverse vibration platen 2 is provided with a first convex pad 202 configured in the shape of the interface with the first groove 601. When the first transverse vibration platen 2 is fixed on the first convex block 6, the first convex pad 202 is embedded in the first groove 601 and abuts against the side of the first end of the solid propellant tensile specimen 8.

[0071] At least one fourth threaded hole 702 is provided on the second convex block 7 at a position around the side opening of the second groove 701, and the second transverse vibration platen 3 is provided with a second through hole 301 corresponding to the fourth threaded hole 702. During the test, the second transverse vibration platen 3 is detachably connected to the second convex block 7 through the cooperation of the second through hole 301, the fourth threaded hole 702 and the screw to cover the side opening of the second groove 701.

[0072] As a preferred embodiment, when the second transverse vibration platen 3 covers the side opening of the second groove 701, part of the second transverse vibration platen 3 is embedded in the second groove 701, and then abuts against the side of the second end of the solid propellant tensile specimen 8, thereby ensuring the fixation of the second end of the solid propellant tensile specimen 8. Specifically, the second transverse vibration platen 3 is provided with a second convex pad 302 configured in the shape of the interface with the second groove 701. When the second transverse vibration platen 3 is fixed on the second convex block 7, the second convex pad 302 is embedded in the second groove 701 and abuts against the side of the second end of the solid propellant tensile specimen 8.

[0073] A connecting structure is provided on the lateral vibration base 1 for fixing the lateral vibration base 1 on the electric vibration test bench. Specifically, a plurality of first threaded holes 401 are arranged at intervals along the lateral direction on the bottom plate 4, the axial direction of the first threaded hole 401 is parallel to the vertical direction, and each first threaded hole 401 passes through the bottom plate 4 in the vertical direction. Preferably, a plurality of second threaded holes 402 are also arranged at intervals along the lateral direction on the side of the bottom plate 4, the axial direction of the second threaded hole 402 is perpendicular to the vertical direction, and the first threaded hole 401 passes through the bottom plate 4 in the horizontal direction. When performing a vibration test, since the first threaded hole 401 and the second threaded hole 402 are perpendicular to each other, the first threaded hole 401 or the second threaded hole 402 can be switched to fix the lateral vibration base 1 on the electric vibration test system, and the fixing direction of the lateral vibration test device can be changed to realize lateral vibration loading of the solid propellant tensile specimen 8 in different directions.

[0074] When the lateral vibration test device in this embodiment conducts a vibration test on the solid propellant tensile specimen 8, the lateral vibration base 1 is fixed through the first threaded hole 401 or the second threaded hole 402, and the solid propellant tensile specimen 8 is placed in the first groove 601 and the second groove 701 of the lateral vibration base 1. The first lateral vibration pressure plate 2 and the second lateral vibration pressure plate 3 are respectively installed to fix the solid propellant tensile specimen 8 on the lateral vibration test device. During the test, an infrared thermal imager is used to monitor the surface temperature of the test section of the solid propellant tensile specimen 8. If the infrared thermal imager is placed on the side of the lateral vibration device, when the vibration test device vibrates in the direction fixed by the first threaded hole 401, the infrared thermal imager monitors the viewing angle as shown in the attached figure. Figure 6 When the vibration test device vibrates in the direction fixed by the second threaded hole 402, the infrared thermal imager monitors the viewing angle as shown in the attached figure. Figure 7 shown.

[0075] Example 2

[0076] This embodiment discloses a lateral vibration test method for a solid propellant tensile specimen, and a lateral vibration test is performed on the solid propellant tensile specimen by using the lateral vibration test device of Embodiment 1.

[0077] The lateral vibration test method in this embodiment includes five parts: pre-test preparation, vibration table test, first electron microscope scanning, uniaxial constant speed tensile test and second electron microscope scanning.

[0078] The process of preparation before the test is:

[0079] 1) Label the solid propellant tensile specimen to be tested, and use a scanning electron microscope to take the original microstructure image of the surface of the test section on the solid propellant tensile specimen;

[0080] 2) Clean the surface measuring points of the solid propellant tensile specimen and locate them with a marker pen, attach the strain gauge to the surface measuring points of the solid propellant tensile specimen and weld the wires to provide conditions for strain field measurement during the test;

[0081] 3) Device assembly: Assemble the lateral vibration test device and place the solid propellant tensile specimen;

[0082] 4) Construction of vibration test platform: adjust the vibration platform of the electric vibration test system to a suitable height, and then fix the lateral vibration test device with the solid propellant tensile specimen placed on the vibration platform of the electric vibration test system. When the test starts, the vibration platform performs vertical reciprocating motion under the set acceleration conditions, and the reciprocating motion is transmitted to the solid propellant tensile specimen by the lateral vibration test device to realize the loading of vibration acceleration load; fix an infrared imager around the electric vibration test system, with the infrared imager lens facing the temperature monitoring surface, connect the power cord and network cable of the infrared imager to capture the surface temperature field data of the solid propellant tensile specimen and transmit and store the image data in real time; connect the strain gauge wire to the strain gauge to record and store the strain field data during the vibration process in real time.

[0083] The process of the vibration table test is as follows:

[0084] 1) Test condition setting: According to the vibration data collected in the actual working conditions, select the waveform, frequency, acceleration amplitude or power spectrum density of the test load in the electric vibration test system, select the vibration monitoring and control channel, and set the vibration time;

[0085] 2) Start the test: turn on the power amplifier in the electric vibration test system, check the test conditions to ensure that the test conditions are set correctly, check the test platform wiring to ensure that all physical quantities can be detected and recorded in real time, and then start the test;

[0086] 3) First lateral vibration test: fix the lateral vibration test device with the solid propellant tensile specimen placed on it to the vibration platform fixed to the electric vibration test system with the first bolt hole, and conduct the first lateral vibration test. Record the surface temperature cloud map of the solid propellant tensile specimen at different times during the vibration process, record the curve of the maximum temperature of the surface of the solid propellant tensile specimen changing with time during the vibration process, and record the curve of the strain changing with time at each surface measuring point;

[0087] 4) Second lateral vibration test: fix the lateral vibration test device with the solid propellant tensile specimen placed on it to the vibration platform fixed to the electric vibration test system with the second bolt hole, and conduct the first lateral vibration test, record the surface temperature cloud map of the solid propellant tensile specimen at different times during the vibration process, record the curve of the maximum temperature of the surface of the solid propellant tensile specimen changing with time during the vibration process, and record the curve of the strain changing with time at each surface measuring point;

[0088] 5) Result analysis: Analyze the intrinsic relationship between temperature rise and structural damage based on the surface temperature distribution cloud map of the solid propellant tensile specimen; combine the temperature change curve with the strain change curve to analyze the mechanism of temperature rise; compare the maximum surface temperature and strain of each point of the solid propellant tensile specimen at different times with the theoretical model to verify the accuracy of the model.

[0089] The process of the first electron microscope scanning is:

[0090] 1) Solid propellant tensile specimen processing: Select 2 to 4 solid propellant tensile specimens from a group of solid propellant tensile specimens after vibration, and slice the test sections of the selected solid propellant tensile specimens;

[0091] 2) Use a scanning electron microscope to take microscopic structural images of the surface of the test section after vibration;

[0092] 3) Compare the surface microstructure image of the solid propellant tensile specimen after vibration with the original microstructure image before vibration to analyze the influence of vibration load on the propellant microstructure in actual engineering.

[0093] The process of uniaxial constant speed tensile test is as follows:

[0094] 1) Dimension measurement: prepare several solid propellant tensile specimens without vibration and several solid propellant tensile specimens after vibration, and measure and record the dimensions of the test section of each solid propellant tensile specimen;

[0095] 2) Start the test: Stretch the unvibrated solid propellant tensile specimen and the vibrated solid propellant tensile specimen at a stretching rate of 2 mm / min until they break, and record the force-displacement curve during stretching;

[0096] 3) Data processing: Calculate the initial modulus, tensile strength, breaking strength, maximum elongation and elongation at break of each solid propellant tensile specimen;

[0097] 4) Result analysis: Compare the initial modulus, tensile strength, breaking strength, maximum elongation and breaking elongation of the solid propellant tensile specimens without vibration and the solid propellant tensile specimens after vibration to obtain the degradation law of the mechanical properties of the propellant under vibration conditions.

[0098] The process of the second electron microscope scanning is:

[0099] 1) Test piece processing: Slice the fracture surface of the solid propellant tensile specimen after it is broken;

[0100] 2) Start the experiment: Use a scanning electron microscope to take microscopic structural images of the fracture surface;

[0101] 3) Compare the fracture microstructure image of the solid propellant tensile specimen after vibration with the fracture microstructure image without vibration to analyze the effect of vibration aging on the propellant failure mode.

[0102] In this embodiment, with the help of the existing electric vibration test system, the vibration acceleration load is applied to the test piece through the reciprocating motion of the vibration table plane, which is different from the axial tension and compression on the two ends of the test piece, and can achieve the simulation of the actual working conditions.

[0103] The axial vibration of solid propellant can be regarded as the axial tension and compression problem of the rod, which is only subject to the axial normal stress, while the lateral vibration of solid propellant can be regarded as the fixed-support beam at both ends being subjected to the uniform load. The tensile specimen of solid propellant is subjected to the combined action of normal stress and shear stress, which is closer to the complex load in actual working conditions. The solid propellant lateral vibration test method of this embodiment can explore the damage mechanism and mechanical property degradation law of solid propellant under the combined action of normal stress and shear stress.

[0104] During the test, this embodiment uses an infrared imager, a strain measurement system and related software to monitor the temperature field and strain field of the test piece in real time during the vibration process and store the test data, which can be used for theoretical analysis and verification of solid propellant acceleration vibration, filling the gap in solid propellant lateral vibration test equipment and test methods.

[0105] According to the test process in this embodiment, the temperature rise phenomenon and deformation trend during the vibration of the propellant can be analyzed and theoretically verified, and the microstructural changes, mechanical property degradation and failure mode changes caused by vibration can also be experimentally observed, forming a complete solid propellant lateral vibration test and analysis system.

[0106] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A solid propellant tensile specimen lateral vibration test device, characterized in that: It includes a transverse vibration base, a first transverse vibration platen and a second transverse vibration platen; The lateral vibration base is symmetrically provided with a first groove and a second groove in the lateral direction, and there is a gap between the first groove and the second groove for embedding two ends of the solid propellant tensile specimen; The first transverse vibration platen is detachably connected to the transverse vibration base and partially embedded in the first groove, and the second transverse vibration platen is detachably connected to the transverse vibration base and partially embedded in the second groove; The lateral vibration base is provided with a connecting structure for fixing the lateral vibration base on the electric vibration test bench.

2. The solid propellant tensile specimen lateral vibration test device according to claim 1, characterized in that: The connection structure comprises a plurality of first threaded holes arranged on the lateral vibration base at intervals in the lateral direction; The axial direction of the first threaded hole is parallel to the vertical direction.

3. The solid propellant tensile specimen lateral vibration test device according to claim 1 or 2, characterized in that: The connection structure comprises a plurality of second threaded holes arranged on the lateral vibration base at intervals in the lateral direction; The axial direction of the second threaded hole is perpendicular to the vertical direction.

4. The solid propellant tensile specimen lateral vibration test device according to claim 1 or 2, characterized in that: A first convex pad is disposed on the first transverse vibration platen, and the first convex pad is embedded in the first groove; A second convex pad is disposed on the second transverse vibration pressing plate, and the second convex pad is embedded in the second groove.

5. A solid propellant tensile specimen lateral vibration test method, characterized in that: A lateral vibration test is performed on a solid propellant tensile specimen using the apparatus described in any one of claims 1 to 4; The lateral vibration test method includes preparation before the test, a vibration table test, a first electron microscope scan, a uniaxial constant speed tensile test and a second electron microscope scan.

6. The solid propellant tensile specimen lateral vibration test method according to claim 5, characterized in that: The process of preparation before the test is as follows: The solid propellant tensile specimen to be tested is labeled, and the original microstructure image of the surface of the test section on the solid propellant tensile specimen is taken using a scanning electron microscope; Clean the surface measuring points of the solid propellant tensile specimen and locate them with a marker pen, attach the strain gauges to the surface measuring points of the solid propellant tensile specimen and weld the wires to provide conditions for strain field measurement during the test; Assemble the lateral vibration test apparatus and place the solid propellant tensile specimens; Adjust the vibration platform of the electric vibration test system to a suitable height, and then fix the lateral vibration test device with the solid propellant tensile specimen placed on it to the vibration platform of the electric vibration test system. When the test starts, the vibration platform performs vertical reciprocating motion under the set acceleration conditions, and the reciprocating motion is transmitted to the solid propellant tensile specimen by the lateral vibration test device to realize the loading of the vibration acceleration load; An infrared imager is fixed around the electric vibration test system, with the infrared imager lens facing the temperature monitoring surface. The power cord and network cable of the infrared imager are connected to capture the surface temperature field data of the solid propellant tensile specimen and transmit and store the image data in real time; Connect the strain gauge wire to the strain meter to record and store the strain field data during the vibration process in real time.

7. The solid propellant tensile specimen lateral vibration test method according to claim 5 or 6, characterized in that: The process of the vibration table test is as follows: According to the vibration data collected in actual working conditions, select the waveform, frequency, acceleration amplitude or power spectrum density of the test load in the electric vibration test system, select the vibration monitoring and control channel, and set the vibration time; Turn on the power amplifier in the electrodynamic vibration test system, check the test conditions to ensure that the test conditions are set correctly, check the test platform wiring to ensure that all physical quantities can be detected and recorded in real time, and then start the test; The lateral vibration test device with the solid propellant tensile specimen placed thereon is fixed to the vibration platform fixed to the electric vibration test system with the first bolt hole, and the first lateral vibration test is carried out, and the surface temperature cloud diagram of the solid propellant tensile specimen at different times during the vibration process is recorded, and the curve of the maximum temperature of the surface of the solid propellant tensile specimen changing with time during the vibration process is recorded, and the curve of the strain changing with time at each surface measuring point is recorded; The lateral vibration test device with the solid propellant tensile specimen placed thereon is fixed to the vibration platform fixed to the electric vibration test system through the second bolt hole, and the first lateral vibration test is carried out, and the surface temperature cloud diagram of the solid propellant tensile specimen at different times during the vibration process is recorded, and the curve of the maximum temperature of the surface of the solid propellant tensile specimen changing with time during the vibration process is recorded, and the curve of the strain changing with time at each surface measuring point is recorded; The intrinsic relationship between temperature rise and structural damage is analyzed based on the surface temperature distribution cloud diagram of solid propellant tensile specimens; The temperature-time curve and the strain-time curve are combined to analyze the mechanism of temperature rise. The maximum temperature and strain at each point on the surface of the solid propellant tensile specimen at different times are compared with the theoretical model to verify the accuracy of the model.

8. The solid propellant tensile specimen lateral vibration test method according to claim 7, characterized in that: The process of the first electron microscope scanning is: Select 2 to 4 solid propellant tensile specimens from a group of solid propellant tensile specimens after vibration, and slice the test sections of the selected solid propellant tensile specimens; Use a scanning electron microscope to take microscopic structural images of the test section surface after vibration; The surface mesostructure image of the solid propellant tensile specimen after vibration is compared with the original mesostructure image before vibration to analyze the effect of vibration load on the propellant mesostructure in actual engineering.

9. The solid propellant tensile specimen lateral vibration test method according to claim 8, characterized in that: The process of the uniaxial constant speed tensile test is as follows: Prepare several solid propellant tensile specimens before and after vibration, and measure and record the dimensions of the test section of each solid propellant tensile specimen; The unvibrated solid propellant tensile specimen and the vibrated solid propellant tensile specimen were stretched at a stretching rate of 1 to 3 mm / min until they broke, and the force-displacement curve during stretching was recorded; Calculate the initial modulus, tensile strength, breaking strength, maximum elongation and elongation at break of each solid propellant tensile specimen; By comparing the initial modulus, tensile strength, breaking strength, maximum elongation and breaking elongation of the solid propellant tensile specimens without vibration and the solid propellant tensile specimens after vibration, the degradation law of the mechanical properties of the propellant under vibration conditions was obtained.

10. The solid propellant tensile specimen lateral vibration test method according to claim 9, characterized in that: The process of the second electron microscope scanning is: The fracture surface of the solid propellant tensile specimen was sliced ​​and the microstructure image of the fracture surface was taken using a scanning electron microscope. The microstructure images of the fracture surface of the solid propellant tensile specimen after vibration are compared with those of the non-vibrated specimen to analyze the effect of vibration aging on the failure mode of the propellant.

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