A loading device and loading method for dynamic biaxial compression of solid propellant

Abstract

The present invention relates to the technical field of material mechanical property test and testing, and in particular to a loading device and a loading method for dynamic biaxial compression of solid propellant, comprising an upper clamp and a lower clamp connected in matching manner, wherein the upper clamp comprises an upper clamp body and an upper loading platform, and a disc-shaped upper pressure plate is fixedly connected to the upper loading platform; the lower clamp comprises a lower clamp body and a lower loading platform, and a bottom fixing sleeve is fixedly connected to the lower loading platform; the upper clamp body and the lower clamp body are buckled with each other, and the area between the upper clamp body and the lower clamp body is a clamping area; the clamp designed by the present invention can realize a loading ratio of 1:1 on a high strain rate hydraulic servo testing machine, and the strain rate covers 1-100S ‑1 Dynamic loading and other biaxial compression loading tests. The suspension structure composed of a double-hole wire lock and a thin rope makes the fixture and the test piece surface slightly contact, avoiding direct operation on the test piece and reducing the prestress and damage caused by the weight of the fixed test piece and the fixture.

Description

Technical Field

[0001] The invention relates to the technical field of material mechanical property test and testing, and in particular to a loading device and a loading method for dynamic biaxial compression of solid propellant. Background Art

[0002] At present, the test methods involved in the mechanical properties test standards of solid propellant materials mainly include quasi-static uniaxial tension and compression test methods with relatively mature test systems, and there is still a lack of effective test methods for testing the mechanical properties of solid propellants under dynamic biaxial compression loading. However, the mechanical properties of solid propellants are not only significantly affected by the strain rate change factor, but also by the stress state factor. There are obvious differences between uniaxial and biaxial mechanical properties. Therefore, in order to accurately grasp the mechanical properties of propellants under dynamic biaxial compression loading and ensure that they meet the application requirements under actual working conditions, it is necessary to carry out corresponding test method research.

[0003] Due to the complexity of the mechanical properties of solid propellant materials and the limitations of the equipment testing principle, the Split Hopkinson Pressure Bar (SHPB) device cannot directly and effectively carry out mechanical properties tests of solid propellants under biaxial dynamic loading. In addition, due to the limitation of loading rate, conventional biaxial mechanical properties testing machines cannot directly carry out mechanical properties tests under dynamic loading. Therefore, there is still a lack of test methods for testing the mechanical properties of solid propellants under dynamic biaxial compression loading, and new test methods must be designed to carry out corresponding research. In comparison, the INSTRON160 / 100-20 uniaxial high strain rate hydraulic servo testing machine produced by INSTRON in the United States has a maximum compression speed of 20m / s and a maximum measurement force of 100kN. It can carry out compression mechanical properties tests of materials under dynamic loading conditions, and because the equipment is hydraulically controlled, the measurement accuracy is higher. However, the testing machine cannot directly cooperate with the test piece to realize the biaxial mechanical properties test of the material, so a new test fixture is needed to be used with the testing machine to study the biaxial high-speed compression mechanical properties of solid propellant materials. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies and defects of the background technology and provide a new loading device and loading method for dynamic biaxial compression of solid propellant.

[0005] The present invention discloses a loading device for dynamic biaxial compression of solid propellant, comprising an upper clamp and a lower clamp connected to each other, wherein the upper clamp comprises an upper clamp body and an upper loading platform fixedly arranged on the top of the upper clamp body, and a disc-shaped upper pressure plate is fixedly connected to the upper loading platform;

[0006] The lower clamp comprises a lower clamp body and a lower loading platform fixedly arranged at the lower end of the lower clamp body, and a bottom fixing sleeve is fixedly connected to the lower loading platform;

[0007] The upper clamping body and the lower clamping body are buckled with each other, and the area between the upper clamping body and the lower clamping body is a clamping area, and the clamping area is in a rectangular parallelepiped shape, and one of the planes where the diagonal line of the clamping area is located is parallel to the vertical plane;

[0008] A guide device is also provided between the upper clamping body and the lower clamping body;

[0009] A suspension device is respectively arranged at both ends of the upper clamping body and the lower clamping body, and the suspension device comprises a suspension fixing device and a thin rope, one end of the thin rope is fixedly connected to the suspension fixing device, and the other end is fixedly connected to the suspension fixing device after being wound around the same side of the upper clamping body and the lower clamping body.

[0010] Preferably, the upper clamp body comprises a first loading arm and a second loading arm that are fixedly connected, the first loading arm and the second loading arm are both plate-shaped, one end of the first loading arm is fixedly connected to one end of the second loading arm, and the first loading arm and the second loading arm are arranged perpendicular to each other;

[0011] The lower clamp body comprises a third loading arm and a fourth loading arm which are fixedly connected, the third loading arm and the fourth loading arm are both plate-shaped, one end of the third loading arm is fixedly connected to one end of the fourth loading arm, and the third loading arm and the fourth loading arm are arranged perpendicular to each other;

[0012] A cross-through groove is provided in the middle of the second loading arm and the third loading arm, and a loading plate is provided in the middle of the first loading arm and the fourth loading arm, the loading plate on the first loading arm and the cross-through groove on the third loading arm are matched and cross-connected, and the cross-through groove on the second loading arm and the loading plate on the fourth loading arm are matched and cross-connected;

[0013] The first loading arm and the third loading arm, and the second loading arm and the fourth loading arm are also connected respectively via auxiliary guide structures.

[0014] Preferably, the auxiliary guide structure comprises a long through-hole slide groove, and the first loading arm, the second loading arm, the third loading arm and the fourth loading arm are all provided with a through-hole slide groove, the through-hole slide grooves on the first loading arm and the fourth loading arm are arranged on both sides of the loading plate on the loading arm, and the through-hole slide grooves on the second loading arm and the third loading arm are arranged on both sides of the cross-through hole on the loading arm;

[0015] The through-hole slide grooves on the same loading arm all extend along the end of the loading arm away from the clamping area, and the loading arm located on the side of the through-hole slide groove away from the cross-through hole or the loading plate is the loading branch arm; the loading branch arm crosses through the corresponding through-hole slide grooves on the connected loading arm;

[0016] One through-hole slide groove is set on the first loading arm and located on the same side of the loading plate, one through-hole slide groove is set on the second loading arm and the third loading arm and located on the same side of the cross-through hole, and two through-hole slide grooves are set on the fourth loading arm and located on the same side of the loading plate.

[0017] Preferably, the guide device comprises a guide frame and two guide rods, and guide holes for the guide rods to pass through are respectively provided on both ends of the upper loading platform;

[0018] The two guide rods are both vertically arranged, and one end of the guide rod is fixedly connected to one side of the guide frame, which side is the bottom side of the guide frame, and the other end passes through the guide hole on the upper loading platform and is fixedly connected to the other side corresponding to the bottom side of the guide frame, which side is the top side of the guide frame. The bottom side of the guide frame is fixedly connected to the lower loading platform, and the guide rod is connected to the upper loading platform through a linear bearing;

[0019] A channel for the upper loading platform to move up and down is arranged on the top edge of the guide frame between the two guide rods, and the upper loading platform is arranged in the channel.

[0020] Preferably, it further comprises two loading guide plates, namely a first loading guide plate and a second loading guide plate, wherein the first loading guide plate and the second loading guide plate are arranged parallel to each other;

[0021] The second loading arm is provided with a first loading guide hole, the first loading guide hole is connected with the cross-through groove on the loading arm, one end of the first loading guide plate passes through the first loading guide hole on the second loading arm and abuts against the loading plate on the fourth loading arm;

[0022] The third loading arm is provided with a second loading guide hole, the second loading guide hole is connected with the cross-through groove on the loading arm, one end of the second loading guide plate passes through the second loading guide hole on the third loading arm and abuts against the loading plate on the first loading arm;

[0023] The first loading guide plate is arranged perpendicularly to the loading plate on the fourth loading arm, and the second loading guide plate is arranged perpendicularly to the loading plate on the first loading arm;

[0024] The clamping area is an area surrounded by two loading plates and two loading guide plates.

[0025] Preferably, a side of the first loading guide plate facing the clamping area is flush with a side of the second loading arm facing the clamping area;

[0026] A side of the second loading guide plate facing the clamping area is arranged flush with a side of the third loading arm facing the clamping area.

[0027] Preferably, the first loading guide plate is slidably connected to the first loading guide hole, and the second loading guide plate is slidably connected to the second loading guide hole.

[0028] Preferably, the lower loading platform is an I-shaped lower loading platform in cross section, the bottom fixing sleeve is a truncated cone, an I-shaped blind hole matching the lower loading platform is provided on the bottom fixing sleeve, one end of the lower loading platform is fixedly connected to the connection between the third loading arm and the fourth loading arm, and the other end extends into the I-shaped blind hole, and the bottom fixing sleeve is fixedly connected to the lower loading platform by a threaded hole provided on the circumferential surface of the bottom fixing sleeve and a bolt matched and connected in the threaded hole;

[0029] The bottom fixing sleeve is provided with a plurality of fixing threaded holes for connecting to the base of the testing machine, and the fixing threaded holes are evenly distributed along the circumference of the bottom fixing sleeve.

[0030] Preferably, the suspension fixing device is a double-hole wire locker.

[0031] A loading method for dynamic biaxial compression of solid propellant, using a loading device for dynamic biaxial compression of solid propellant for loading, comprises the following steps:

[0032] Step 1: Use four high-strength screws that match the fixed threaded holes to fix the bottom fixing sleeve to the base of the test machine, ensuring that the bottom fixing sleeve is completely fixed to the base of the test machine;

[0033] Step 2, insert the end of the lower loading platform away from the lower clamping body into the I-shaped blind hole on the bottom fixing sleeve, and use high-strength screws to extend from the threaded holes on the circumference of the bottom fixing sleeve and fix it to the lower loading platform to ensure that the lower clamping body and the bottom fixing sleeve are fixedly matched, and wrap the two ends of the upper clamping body and the lower clamping body with thin wires respectively, and connect the two ends of the same thin wire through a hanging fixture;

[0034] Step 3, match and connect the upper clamp and the lower clamp, and use the guide rod to pass through the guide hole to ensure that the upper clamp body and the lower clamp body are aligned with each other, and then evenly apply the drag reducing agent for reducing friction on the first loading guide plate, the second loading guide plate, the first loading arm, the second loading arm, the third loading arm, the fourth loading arm, the loading arm on the loading arm, and the through-hole slide groove;

[0035] Step 4: Place the metal test specimen into the clamping area, and then use the hanging fixture to pre-tighten the thin rope until the first loading guide plate passing through the first loading guide hole slightly touches the surface of the specimen to avoid the upper fixture's gravity causing pre-damage to the material. At this time, use the double-hole wire locker to lock the thin rope;

[0036] Step 5, move the first loading guide plate, take out the metal sample, put in a solid propellant cube sample to be tested with the same size as the metal verification sample, and reset the first loading guide plate;

[0037] Step 6: Start the testing machine and reserve an accelerating displacement that enables the testing machine to reach a specified loading rate to achieve constant strain rate loading;

[0038] Step 7: Set the loading rate according to different test conditions and conduct biaxial compression test under dynamic loading. The strain rate range of the experiment is 1-100S. -1 , the strain or deformation is measured by the sensor, the force-displacement curve is output, and the true stress-strain curve under the stress state is obtained by the following formula;

[0039]

[0040]

[0041] Where F is the loading force acting on the fixture; σ true is the true stress; ε true is the true strain; U is the displacement of the fixture along the vertical direction; L0 and W0 are the original length and width of the specimen, respectively.

[0042] The invention has the advantages of simple structure, convenient use and low cost, and is suitable for dynamic biaxial loading compression mechanical tests of high strain rate material testing machines.

[0043] The fixture designed in this invention can achieve a loading ratio of 1:1 on the INSTRON160 / 100-20 high strain rate hydraulic servo testing machine, and the strain rate range covers 1-100S -1 Biaxial compression loading test of solid propellant.

[0044] The fixture designed by the present invention matches the configuration of the test piece, the test piece is placed in the clamping area, and the fixture and the test piece surface are micro-contacted through the suspension device, so as to avoid direct operation on the test piece and reduce the prestress and damage caused by the fixed test piece and the deadweight of the fixture; the guide device and the loading guide plate designed by the present invention can reduce the influence of friction on the test results as much as possible; the device designed by the present invention has uniform load distribution and has sufficient accuracy for realizing biaxial compression loading, and the maximum load-bearing capacity can reach 100KN, with good universality, and can provide a reference for mechanical property tests of non-metallic materials with relatively large strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a schematic diagram of the structure of the present invention.

[0046] Figure 2 for Figure 1 Left view of .

[0047] Figure 3 It is a schematic diagram of the specific structure of the upper clamp of the present invention.

[0048] Figure 4 for Figure 3 Top view of the .

[0049] Figure 5 It is a schematic diagram of the bottom fixing sleeve structure of the present invention.

[0050] Figure 6 for Figure 5 Top view of the .

[0051] Figure markings: 1-upper pressure plate, 2-upper loading platform, 3-guide rod, 4-fourth loading arm, 5-second loading arm, 6-lower loading platform, 7-first loading guide plate, 8-first loading arm, 9-third loading arm, 10-through hole slide groove, 11-clamping area, 12-second loading guide plate, 13-bottom fixing sleeve, 14-guide frame, 15-linear bearing, 16-first loading guide hole, 17-guide hole. DETAILED DESCRIPTION

[0052] The present invention discloses a loading device for dynamic biaxial compression of solid propellant, comprising an upper fixture and a lower fixture connected to each other, wherein the upper fixture comprises an upper fixture body and an upper loading platform 2 fixedly arranged on the top of the upper fixture body, and a disc-shaped upper pressure plate 1 is fixedly connected to the upper loading platform 2;

[0053] The lower fixture comprises a lower clamp body and a lower loading platform 6 fixedly arranged at the lower end of the lower clamp body, and a bottom fixing sleeve 13 is fixedly connected to the lower loading platform 6;

[0054] The upper clamping body and the lower clamping body are buckled with each other, and the area between the upper clamping body and the lower clamping body is a clamping area 11, and the clamping area 11 is in the shape of a rectangular parallelepiped, and one plane in the plane where the diagonal line of the clamping area 11 is located is parallel to the vertical plane; a guide device is also provided between the upper clamping body and the lower clamping body;

[0055] A suspension device is respectively arranged at both ends of the upper clamping body and the lower clamping body, and the suspension device comprises a suspension fixing device and a thin rope, one end of the thin rope is fixedly connected to the suspension fixing device, and the other end is fixedly connected to the suspension fixing device after being wound around the same side of the upper clamping body and the lower clamping body.

[0056] Preferably, the upper clamp body comprises a first loading arm 8 and a second loading arm 5 which are fixedly connected, the first loading arm 8 and the second loading arm 5 are both plate-shaped, one end of the first loading arm 8 is fixedly connected to one end of the second loading arm 5, and the first loading arm 8 and the second loading arm 5 are arranged perpendicular to each other;

[0057] The lower clamp body comprises a third loading arm 9 and a fourth loading arm 4 which are fixedly connected, the third loading arm 9 and the fourth loading arm 4 are both plate-shaped, one end of the third loading arm 9 is fixedly connected to one end of the fourth loading arm 4, and the third loading arm 9 and the fourth loading arm 4 are arranged perpendicular to each other;

[0058] A cross-through groove is provided in the middle of the second loading arm 5 and the third loading arm 9, and a loading plate is provided in the middle of the first loading arm 8 and the fourth loading arm 4. The loading plate on the first loading arm 8 and the cross-through groove on the third loading arm 9 are matched and cross-connected, and the cross-through groove on the second loading arm 5 and the loading plate on the fourth loading arm 4 are matched and cross-connected;

[0059] The first loading arm 8 and the third loading arm 9, the second loading arm 5 and the fourth loading arm 4 are also connected respectively via auxiliary guide structures.

[0060] The auxiliary guide structure includes a long through-hole slide groove 10, and the first loading arm 8, the second loading arm 5, the third loading arm 9 and the fourth loading arm 4 are all provided with a through-hole slide groove 10. The through-hole slide grooves 10 on the first loading arm 8 and the fourth loading arm 4 are arranged on both sides of the loading plate on the loading arm, and the through-hole slide grooves 10 on the second loading arm 5 and the third loading arm 9 are arranged on both sides of the cross-through hole on the loading arm;

[0061] The through-hole slide grooves 10 on the same loading arm all extend along the end of the loading arm away from the clamping area 11, and the loading arm located on the side of the through-hole slide groove 10 away from the cross-through hole or the loading plate is a loading branch arm; the loading branch arm crosses through the corresponding through-hole slide groove 10 on the connected loading arm;

[0062] The first loading arm 8 has one through-hole slide groove 10 on the same side of the loading plate, the second loading arm 5 and the third loading arm 9 have one through-hole slide groove 10 on the same side of the cross-through hole, and the fourth loading arm 4 has two through-hole slide grooves 10 on the same side of the loading plate.

[0063] The guide device includes a guide frame 14 and two guide rods 3. Guide holes 17 for the guide rods 3 to pass through are respectively provided on both ends of the upper loading platform 2.

[0064] The two guide rods 3 are both vertically arranged, and one end of the guide rod 3 is fixedly connected to one side of the guide frame 14, which side is the bottom side of the guide frame 14, and the other end passes through the guide hole 17 on the upper loading platform 2 and is fixedly connected to the other side corresponding to the bottom side of the guide frame 14, which side is the top side of the guide frame 14. The bottom side of the guide frame 14 is fixedly connected to the lower loading platform 6, and the guide rod 3 and the upper loading platform 2 are connected through a linear bearing 15;

[0065] A channel for the upper loading platform 2 to move up and down is arranged on the top edge of the guide frame 14 between the two guide rods 3, and the upper loading platform 2 is arranged in the channel.

[0066] It also includes two loading guide plates, namely a first loading guide plate 7 and a second loading guide plate 12, wherein the first loading guide plate 7 and the second loading guide plate 12 are arranged parallel to each other;

[0067] The second loading arm 5 is provided with a first loading guide hole 16, the first loading guide hole 16 is connected with the cross-through groove on the loading arm, one end of the first loading guide plate 7 passes through the first loading guide hole 16 on the second loading arm 5, and abuts against the loading plate on the fourth loading arm 4;

[0068] The third loading arm 9 is provided with a second loading guide hole 17, the second loading guide hole 17 is connected with the cross-through groove on the loading arm, one end of the second loading guide plate 12 passes through the second loading guide hole 17 on the third loading arm 9, and abuts against the loading plate on the first loading arm 8;

[0069] The first loading guide plate 7 is arranged perpendicularly to the loading plate on the fourth loading arm 4, and the second loading guide plate 12 is arranged perpendicularly to the loading plate on the first loading arm 8;

[0070] The clamping area 11 is an area surrounded by two loading plates and two loading guide plates. The widths of the first loading guide plate 7 and the second loading guide plate 12 are set as needed, so that the clamping area 11 is in a cube shape.

[0071] A side of the first loading guide plate 7 facing the clamping area 11 is arranged flush with a side of the second loading arm 5 facing the clamping area 11;

[0072] A side of the second loading guide plate 12 facing the clamping area 11 is arranged flush with a side of the third loading arm 9 facing the clamping area 11 .

[0073] The first loading guide plate 7 is slidably connected to the first loading guide hole 16 , and the second loading guide plate 12 is slidably connected to the second loading guide hole 17 .

[0074] The lower loading platform 6 is an I-shaped lower loading platform 6 in cross section, the bottom fixing sleeve 13 is a truncated cone, and an I-shaped blind hole matching the lower loading platform 6 is provided on the bottom fixing sleeve 13, one end of the lower loading platform 6 is fixedly connected to the connection between the third loading arm 9 and the fourth loading arm 4, and the other end extends into the I-shaped blind hole, and the bottom fixing sleeve 13 is fixedly connected to the lower loading platform 6 by a threaded hole provided on the circumference of the bottom fixing sleeve 13 and a bolt matched and connected in the threaded hole;

[0075] The bottom fixing sleeve 13 is provided with a plurality of fixing threaded holes for connecting to the base of the testing machine, and the fixing threaded holes are evenly distributed along the circumference of the bottom fixing sleeve 13 .

[0076] The hanging fixture is a double-hole wire lock.

[0077] A loading method for dynamic biaxial compression of solid propellant, using a loading device for dynamic biaxial compression of solid propellant for loading, comprises the following steps:

[0078] Step 1: Use four high-strength screws that match the fixing threaded holes to fix the bottom fixing sleeve 13 to the base of the testing machine, and ensure that the bottom fixing sleeve 13 is completely fixed to the base of the testing machine;

[0079] Step 2, insert the end of the lower loading platform 6 away from the lower clamping body into the I-shaped blind hole on the bottom fixing sleeve 13, and use high-strength screws to extend from the threaded holes on the circumference of the bottom fixing sleeve 13 and fix it to the lower loading platform 6, ensure that the lower clamping body and the bottom fixing sleeve 13 are fixedly matched, and wrap the two ends of the upper clamping body and the lower clamping body with thin wires respectively, and connect the two ends of the same thin wire through a hanging fixture;

[0080] Step 3, match and connect the upper clamp and the lower clamp, and use the guide rod 3 to pass through the guide hole 17 to ensure that the upper clamp body and the lower clamp body are aligned with each other, and then evenly apply the drag reducing agent for reducing friction on the first loading guide plate 7, the second loading guide plate 12, the first loading arm 8, the second loading arm 5, the third loading arm 9, the fourth loading arm 4 and the loading sub-arms on the loading arms and the through-hole slide groove 10;

[0081] Step 4, place the metal test sample into the clamping area 11, and then use the hanging fixture to pre-tighten the thin rope until the first loading guide plate 7 passing through the first loading guide hole 16 slightly touches the surface of the sample to avoid the gravity of the upper clamp causing pre-damage to the material, and then use the double-hole wire locker to lock the thin rope;

[0082] Step 5, move the first loading guide plate 7, take out the metal sample, put in a solid propellant cube sample to be tested with the same size as the metal verification sample, and reset the first loading guide plate 7;

[0083] Step 6: Start the testing machine and reserve an accelerating displacement that enables the testing machine to reach a specified loading rate to achieve constant strain rate loading;

[0084] Step 7: Set the loading rate according to different test conditions and conduct biaxial compression test under dynamic loading. The strain rate range of the experiment is 1-100S. -1 , the strain or deformation is measured by the sensor, the force-displacement curve is output, and the true stress-strain curve under the stress state is obtained by the following formula;

[0085]

[0086]

[0087] Where F is the loading force acting on the fixture; σ true is the true stress; ε true is the true strain; U is the displacement of the fixture along the vertical direction; L0 and W0 are the original length and width of the specimen, respectively.

[0088] The invention has the advantages of simple structure, convenient use and low cost, and is suitable for biaxial dynamic loading compression mechanical tests of high strain rate material testing machines.

[0089] The fixture designed by the present invention can achieve a loading ratio of 1:1 on the INSTRON160 / 100-20 high strain rate hydraulic servo testing machine, and the strain rate covers 1-100S -1 Dynamic loading and biaxial compression loading test.

[0090] The clamp of the present invention is designed to match the configuration of the specimen, the specimen is placed in the area formed by the clamp, and the clamp and the surface of the specimen are slightly contacted through a hanging structure composed of a double-hole wire locker and a thin rope, so as to avoid direct operation on the specimen and reduce prestress and damage caused by the self-weight of the fixed specimen and the clamp;

[0091] The guide device and loading guide plate designed in the present invention can reduce the influence of friction on the test results as much as possible;

[0092] The device designed by the present invention has uniform load distribution and has sufficient loading accuracy for achieving biaxial compression.

Claims

1. A loading method for dynamic biaxial compression of solid propellant, using a loading device for dynamic biaxial compression of solid propellant for loading, characterized in that: The following steps are involved: Step 1: Use four high-strength screws matching the fixing threaded holes to fix the bottom fixing sleeve (13) to the base of the testing machine, and ensure that the bottom fixing sleeve (13) is completely fixed to the base of the testing machine; Step 2, insert the end of the lower loading platform (6) away from the lower clamping body into the I-shaped blind hole on the bottom fixing sleeve (13), and use high-strength screws to extend from the threaded holes on the circumference of the bottom fixing sleeve (13) and fix it to the lower loading platform (6), ensure that the lower clamping body and the bottom fixing sleeve (13) are fixedly matched, and the two ends of the upper clamping body and the lower clamping body are respectively wrapped with thin wires, and the two ends of the same thin wire are connected through a hanging fixing device; Step 3, the upper clamp and the lower clamp are matched and connected to each other, and the guide rod (3) is passed through the guide hole (17) to ensure that the upper clamp body and the lower clamp body are aligned with each other, and then the first loading guide plate (7), the second loading guide plate (12), the first loading arm (8), the second loading arm (5), the third loading arm (9), the fourth loading arm (4) and the loading sub-arms on the loading arms and the through-hole slide groove (10) are evenly coated with a drag reducing agent for reducing friction; Step 4, place the metal test sample into the clamping area (11), and then use the hanging fixture to pre-tighten the thin rope until the first loading guide plate (7) passing through the first loading guide hole (16) slightly touches the surface of the sample to avoid the gravity of the upper clamp causing pre-damage to the material. At this time, use the double-hole wire locker to lock the thin rope; Step 5, move the first loading guide plate (7), take out the metal sample, put in a solid propellant cube sample to be tested with the same size as the metal verification sample, and reset the first loading guide plate (7); Step 6: Start the testing machine and reserve an accelerating displacement that enables the testing machine to reach a specified loading rate to achieve constant strain rate loading; Step 7: Set the loading rate according to different test conditions and conduct biaxial compression test under dynamic loading. The strain rate range of the experiment is 1-100S. -1 , the strain or deformation is measured by the sensor, the force-displacement curve is output, and the true stress-strain curve under the stress state is obtained by the following formula; Where F is the loading force acting on the fixture; σ true is the true stress; ε true is the true strain; U is the displacement of the fixture along the vertical direction; L0 and W0 are the original length and width of the specimen, respectively; The loading device for dynamic biaxial compression of solid propellant comprises an upper clamp and a lower clamp which are matched and connected, the upper clamp comprises an upper clamp body and an upper loading platform (2) fixedly arranged on the top of the upper clamp body, and a disc-shaped upper pressure plate (1) is fixedly connected to the upper loading platform (2); The lower clamp comprises a lower clamp body and a lower loading platform (6) fixedly arranged at the lower end of the lower clamp body, and a bottom fixing sleeve (13) is fixedly connected to the lower loading platform (6); The upper clamping body and the lower clamping body are buckled with each other, and the area between the upper clamping body and the lower clamping body is a clamping area (11), the clamping area (11) is in the shape of a rectangular parallelepiped, and one of the planes in which the diagonal line of the clamping area (11) is located is parallel to the vertical plane; A guide device is also provided between the upper clamping body and the lower clamping body; The upper clamp body and the lower clamp body are respectively provided with a hanging device at both ends, and the hanging device includes a hanging fixture and a thin rope, one end of the thin rope is fixedly connected to the hanging fixture, and the other end is fixedly connected to the hanging fixture after passing through the same side of the upper clamp body and the lower clamp body; The upper clamp body comprises a first loading arm (8) and a second loading arm (5) which are fixedly connected, the first loading arm (8) and the second loading arm (5) are both plate-shaped, one end of the first loading arm (8) is fixedly connected to one end of the second loading arm (5), and the first loading arm (8) and the second loading arm (5) are arranged perpendicular to each other; The lower clamp body comprises a third loading arm (9) and a fourth loading arm (4) which are fixedly connected, the third loading arm (9) and the fourth loading arm (4) are both plate-shaped, one end of the third loading arm (9) is fixedly connected to one end of the fourth loading arm (4), and the third loading arm (9) and the fourth loading arm (4) are arranged perpendicular to each other; A cross-through groove is provided in the middle of the second loading arm (5) and the third loading arm (9), and a loading plate is provided in the middle of the first loading arm (8) and the fourth loading arm (4); the loading plate on the first loading arm (8) and the cross-through groove on the third loading arm (9) are matched and cross-connected, and the cross-through groove on the second loading arm (5) and the loading plate on the fourth loading arm (4) are matched and cross-connected; The first loading arm (8) and the third loading arm (9), the second loading arm (5) and the fourth loading arm (4) are also connected respectively via auxiliary guide structures; The auxiliary guide structure comprises a long strip-shaped through-hole slide groove (10), and the first loading arm (8), the second loading arm (5), the third loading arm (9) and the fourth loading arm (4) are all provided with a through-hole slide groove (10), the through-hole slide groove (10) on the first loading arm (8) and the fourth loading arm (4) are arranged on both sides of the loading plate on the loading arm, and the through-hole slide groove (10) on the second loading arm (5) and the third loading arm (9) are arranged on both sides of the cross-through hole on the loading arm; The through-hole slide grooves (10) on the same loading arm all extend along one end of the loading arm away from the clamping area (11), and the loading arm located on the side of the through-hole slide groove (10) away from the cross-through hole or the loading plate is a loading branch arm; the loading branch arm crosses through the corresponding through-hole slide groove (10) on the connected loading arm; The first loading arm (8) is provided with one through hole slide groove (10) located on the same side of the loading plate, the second loading arm (5) and the third loading arm (9) are provided with one through hole slide groove (10) located on the same side of the cross-through hole, and the fourth loading arm (4) is provided with two through hole slide grooves (10) located on the same side of the loading plate; The guide device comprises a guide frame (14) and two guide rods (3), and guide holes (17) for the guide rods (3) to pass through are respectively provided on both ends of the upper loading platform (2); The two guide rods (3) are both arranged vertically, and one end of the guide rod (3) is fixedly connected to one side of the guide frame (14), which side is the bottom side of the guide frame (14), and the other end passes through a guide hole (17) on the upper loading platform (2) and is fixedly connected to another side corresponding to the bottom side of the guide frame (14), which side is the top side of the guide frame (14). The bottom side of the guide frame (14) is fixedly connected to the lower loading platform (6), and the guide rod (3) is connected to the upper loading platform (2) via a linear bearing (15); A channel for the upper loading platform (2) to move up and down is arranged on the top edge of the guide frame (14) between the two guide rods (3), and the upper loading platform (2) is arranged in the channel; It also includes two loading guide plates, namely a first loading guide plate (7) and a second loading guide plate (12), wherein the first loading guide plate (7) and the second loading guide plate (12) are arranged parallel to each other; The second loading arm (5) is provided with a first loading guide hole (16), the first loading guide hole (16) is connected to the cross-through groove on the loading arm, one end of the first loading guide plate (7) passes through the first loading guide hole (16) on the second loading arm (5) and abuts against the loading plate on the fourth loading arm (4); The third loading arm (9) is provided with a second loading guide hole (17), the second loading guide hole (17) is connected to the cross-through groove on the loading arm, one end of the second loading guide plate (12) passes through the second loading guide hole (17) on the third loading arm (9) and abuts against the loading plate on the first loading arm (8); The first loading guide plate (7) is arranged perpendicularly to the loading plate on the fourth loading arm (4), and the second loading guide plate (12) is arranged perpendicularly to the loading plate on the first loading arm (8); The clamping area (11) is an area surrounded by two loading plates and two loading guide plates; A side of the first loading guide plate (7) facing the clamping area (11) is arranged flush with a side of the second loading arm (5) facing the clamping area (11); A side of the second loading guide plate (12) facing the clamping area (11) is arranged flush with a side of the third loading arm (9) facing the clamping area (11); The first loading guide plate (7) is slidably connected to the first loading guide hole (16), and the second loading guide plate (12) is slidably connected to the second loading guide hole (17); The lower loading platform (6) is a lower loading platform (6) with an I-shaped cross section, the bottom fixing sleeve (13) is truncated, an I-shaped blind hole matching the lower loading platform (6) is arranged on the bottom fixing sleeve (13), one end of the lower loading platform (6) is fixedly connected to the connection between the third loading arm (9) and the fourth loading arm (4), and the other end extends into the I-shaped blind hole, and the bottom fixing sleeve (13) is fixedly connected to the lower loading platform (6) by means of a threaded hole arranged on the circumference of the bottom fixing sleeve (13) and a bolt matched and connected in the threaded hole; The bottom fixing sleeve (13) is provided with a plurality of fixing threaded holes for connecting to the base of the testing machine, and the fixing threaded holes are evenly distributed along the circumference of the bottom fixing sleeve (13).

2. A loading method for dynamic biaxial compression of solid propellant as claimed in claim 1, characterized in that: The hanging fixing device is a double-hole wire locker.

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