Microwave monitoring system for performance of composite material under coupling action of load environment

Abstract

The invention provides a composite material performance microwave monitoring system under a load environment coupling effect, and relates to the technical field of composite materials. The system comprises a stress loading regulation and control assembly, a water circulation assembly, a dielectric constant monitoring assembly and a displacement control assembly, the two ends of the composite material are loaded on the stress loading regulation and control assembly, the stress loading regulation and control assembly can carry out constant stress or variable stress loading on the composite material, the water circulation assembly is installed on the stress loading regulation and control assembly, and the dielectric constant monitoring assembly is installed on the water circulation assembly. The water circulation assembly is used for simulating the use environment of the composite material; the dielectric constant monitoring assembly is mounted on the stress loading regulation and control assembly and is used for detecting the dielectric constant variation of the composite material; the displacement control assembly is installed on the stress loading regulation and control assembly, the stress loading regulation and control assembly, the dielectric constant monitoring assembly and the water circulation assembly move linearly, and whether damage exists in the composite material or not can be judged according to monitored data.

Description

Technical Field

[0001] The invention relates to the technical field of composite materials, in particular to a microwave monitoring system for composite material performance under load-environment coupling. Background Art

[0002] Composite materials are used in aviation, aerospace, military, communications, sports, construction and other fields due to their advantages such as high specific strength, high specific modulus, low density, corrosion resistance and strong design. Composite rods / plates and other structures are commonly used products of composite materials under various civil engineering conditions such as ocean, surface and deep earth. Composite rods / plates are usually accompanied by certain humidity, salt, temperature and other influences under certain working stress conditions, which leads to performance degradation. At present, there are few studies on the durability of composite materials under the combined effects of corrosive ion erosion, hydrolysis, high temperature and humidity accelerated aging and other factors under tensile prestress loading conditions. There is still a lack of effective non-destructive online monitoring methods for changes in moisture content, internal damage, etc. of composite materials (non-conductive fiber reinforced composite materials such as glass fiber, basalt fiber, aramid fiber, etc.) during long-term service. Summary of the invention

[0003] In order to solve a technical problem existing in the prior art, an embodiment of the present invention provides a microwave monitoring system for composite material performance under load-environment coupling, which simulates the load-environment coupling effect on composite materials under natural environmental conditions. The technical solution is as follows:

[0004] A microwave monitoring system for composite material performance under load-environment coupling, comprising:

[0005] A stress loading regulating component, both ends of the composite material are loaded on the stress loading regulating component, and the stress loading regulating component can perform constant stress or variable stress loading on the composite material, wherein the composite material is a non-conductive fiber reinforced composite material such as glass fiber, basalt fiber, aramid fiber, etc., and the material structure is in the form of rods and plates.

[0006] A water circulation component, wherein the water circulation component is mounted on the stress loading regulating component, the composite material passes through the water circulation component, and the water circulation component is used to simulate the use environment of the composite material, wherein the water circulation component supports regulating the salt water concentration, temperature and humidity in the use environment of the composite material according to the actual environment;

[0007] A dielectric constant monitoring component, the dielectric constant monitoring component is installed on the stress loading and regulating component, and the dielectric constant monitoring component is used to detect the change in the dielectric constant of the composite material;

[0008] A displacement control component is installed on the stress loading regulation component, and the displacement control component drives the dielectric constant monitoring component and the water circulation component to move synchronously in a straight line.

[0009] Optionally, the stress loading regulation component includes:

[0010] A stress fixing base, wherein the stress fixing base is arranged horizontally;

[0011] A first fixing bracket and a second fixing bracket, wherein the first fixing bracket and the second fixing bracket are symmetrically mounted at two ends of an upper surface of the stress fixing base;

[0012] A stress driving component, the stress driving component is mounted on the stress fixing base and arranged on the side of the second fixing bracket;

[0013] An anchor, one end of the anchor is mounted on the first fixing bracket, the other end of the anchor is mounted on the stress driving component, and both ends of the composite material are mounted in both ends of the anchor;

[0014] A force sensor, the force sensor being mounted on the first fixing bracket side and on the anchor;

[0015] A stress controller, the stress controller is respectively connected to the force sensor and the stress driving component by telecommunication;

[0016] Wherein, the stress driving component supports and drives the anchor on the same end side to move horizontally.

[0017] Optionally, the stress driving component comprises:

[0018] A servo motor support, the servo motor support being mounted on the surface of the stress fixing base;

[0019] A servo motor, wherein the servo motor is mounted on the servo motor support;

[0020] A first gear and a second gear, wherein upper and lower ends of the second gear are respectively meshed with the first gear, and the second gear is connected to the servo motor through a coupling;

[0021] Screw rods, two of the screw rods are arranged in parallel, and one end of the two screw rods is respectively installed at the center of the two first gears;

[0022] A support plate, wherein two threaded holes are arranged on the support plate, and the two threaded holes are respectively adapted to the two screw rods, and an end of the anchor away from the first fixing bracket is arranged on the end side of the support plate away from the first fixing bracket, and the composite material passes through the support plate and is installed on the end of the anchor away from the first fixing bracket;

[0023] When the servo motor drives the second gear to rotate, the second gear drives the two first gears to rotate, and the two first gears respectively drive the corresponding screws to rotate, the support plate moves along the horizontal direction of the screw and drives the two ends of the anchor to move closer or farther away from each other.

[0024] Optionally, the water circulation component comprises:

[0025] A target water pipe, the target water pipe is arranged above the stress fixing base, one end of the target water pipe is blocked by a first silicone plug, the other end of the target water pipe is blocked by a third silicone plug, the composite material passes through the first silicone plug, the target water pipe and the third silicone plug in sequence, and the target water pipe is installed in a target water pipe insulation sleeve;

[0026] An electric heating tube, an electric heating belt is installed on the outer wall of the electric heating tube, an electric heating belt insulation sleeve is arranged on the outer wall of the electric heating belt, and the electric heating belt insulation sleeve is installed on the first electric heating fixed support and the second electric heating fixed support;

[0027] A temperature controller, the temperature controller is mounted on the temperature controller support, the temperature controller support is mounted on the upper surface of the stress fixing base, the temperature controller is electrically connected to the electric heating belt and the temperature sensor, and the temperature sensor is mounted in the target water pipe;

[0028] A first hose, a second hose and a third hose, one end of the first hose is connected to one end of the electric heating pipe, the other end of the first hose is connected to a circulating water pump, the other end of the circulating water pump is connected to one end of the second hose, the other end of the second hose is connected to the end side wall of one end of the target water pipe through a first tee, one end of the third hose is connected to the other end of the electric heating pipe, and the other end of the third hose is connected to the end side wall of the other end of the target water pipe through a third tee;

[0029] Wherein, the first hose is provided with a first hose insulation sleeve, the second hose is provided with a second hose insulation sleeve, the third hose is provided with a third hose insulation sleeve, and the circulating water pump is electrically connected to the temperature controller;

[0030] A water level monitoring pipe, which is vertically installed above the target water pipe and connected to the target water pipe through a second tee, and a second silicone plug is provided at the end of the water level monitoring pipe;

[0031] A drain valve and a water tank, a fourth three-way connection is arranged on the electric heating pipe and on the same side as the third hose, the fourth three-way connection is connected to the electric heating pipe and the third hose, a drain valve is arranged at the other end of the fourth three-way connection, and a water tank is arranged below the drain valve;

[0032] Optionally, the dielectric constant monitoring component includes:

[0033] A vector network analyzer, wherein the vector network analyzer is mounted on the stress fixing base via an analyzer support;

[0034] A resonant cavity, wherein the resonant cavity is installed at a position of the composite material on the anchor where the water circulation component is not installed, the resonant cavity is sleeved on the outer surface of the composite material, a support pile is arranged on the outer wall of the resonant cavity, the other end of the support pile is installed on the displacement control component, and the displacement control component drives the resonant cavity to move on the composite material through the support pile;

[0035] A waveguide coupler, wherein the waveguide coupler is mounted on the resonant cavity and adapted to the resonant cavity, wherein the upper end port of the waveguide coupler is a microwave input port, and the lower end port of the waveguide coupler is a microwave output port, and the composite material runs through two ports of the waveguide coupler in horizontal left and right directions;

[0036] The vector network analyzer is electrically connected to the waveguide coupler through a microwave input port and a microwave output port of the waveguide coupler.

[0037] Optionally, the displacement control component comprises:

[0038] A fixed platform, the fixed platform is installed parallel to the stress fixing base, and the fixed platform is supported and installed on the stress fixing base through two fixed piles;

[0039] A slide, a pulley is arranged on the bottom surface of the slide, a track adapted to the pulley is arranged on the fixed platform, the slide is slidably connected and installed on the fixed platform, the bottoms of the first electric heating fixed support and the second electric heating fixed support are installed on the upper surface of the slide, and the bottom of the support pile is installed on the slide;

[0040] A mobile driving component, the output end of which is connected to the slide, the mobile driving component supports and drives the slide to move horizontally, and at the same time, the pulley moves synchronously in the track.

[0041] Optionally, the mobile driving component includes:

[0042] A displacement controller and a displacement motor, wherein the displacement controller is electrically connected to the displacement motor, and the displacement motor is installed on a stress fixed base through a displacement mounting pile;

[0043] A conversion joint, wherein the conversion structure is installed at the output end of the displacement motor;

[0044] A lead screw, one end of which is mounted on the conversion joint, and the other end of which is threadedly connected to the slide;

[0045] When the displacement motor drives the lead screw to rotate through the adapter structure, the lead screw drives the slide table to move on the fixed table.

[0046] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0047] The present invention is based on the resonant cavity coupler monitoring scheme adopted by the transmission line theory, and can quickly detect slight changes in the moisture content of the composite material. The method does not need to destroy the sample and can perform online monitoring.

[0048] The invention can be used for monitoring the performance of composite materials such as glass fiber, basalt fiber, aramid fiber and other non-conductive fiber reinforced composite materials.

[0049] The technical means adopted by the present invention is very sensitive to the change of the dielectric properties of the material and therefore has a higher measurement accuracy.

[0050] The water circulation component adopted in the present invention consumes less solution mass, is easy to replace and adjust, and has good experimental convenience.

[0051] The invention has a simple design and can be used to conduct experiments on a single composite material, and can also be used to conduct experiments on multiple composite materials through an extended design, and has good scalability.

[0052] The present invention can select a suitable water circulation component according to the solution type and temperature conditions required for the aging test, and has good feasibility.

[0053] The silicone plug sealing solution adopted in the present invention can better meet the need of sealing the solution to prevent leakage. Silicone rubber has good high and low temperature resistance and corrosion resistance and has good universality. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0055] Figure 1 A schematic diagram of the structure of the device provided by the present invention;

[0056] Figure 2 A schematic diagram of a stress loading control component provided by the present invention;

[0057] Figure 3A schematic diagram of a water circulation component provided by the present invention;

[0058] Figure 4 A schematic diagram of a dielectric constant monitoring component provided by the present invention;

[0059] Figure 5 Schematic diagram of the displacement control component provided by the present invention.

[0060] Reference numerals:

[0061] 1-1, stress fixing base; 1-2, first fixing bracket; 1-3, second fixing bracket; 1-41, servo motor support; 1-42, servo motor; 1-43, first gear; 1-44, second gear; 1-45, screw; 1-46, support plate; 1-5, anchor; 1-6, force sensor; 1-7, stress controller;

[0062] 2-1, vector network analyzer; 2-2, resonant cavity; 2-3, waveguide coupler; 2-4, support pile;

[0063] 3-1, target water pipe; 3-2, electric heating pipe; 3-21, electric heating belt; 3-3, temperature controller; 3-4, first hose; 3-5, second hose; 3-6, third hose; 3-7, water level monitoring pipe; 3-8, water tank; 3-9, circulating water pump; 3-10, drain valve;

[0064] 4-1, fixed table; 4-2, sliding table; 4-3, displacement controller; 4-4, displacement motor; 4-5, conversion joint; 4-6, lead screw; 4-7, pulley. DETAILED DESCRIPTION

[0065] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment 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.

[0066] Unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one", "one" or "the" do not indicate a quantitative limitation, but indicate the existence of at least one. Words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0067] It should be noted that the terms "up", "down", "left", "right", "front", "back", etc. used in the present invention are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0068] like Figures 1 to 5 As shown, a microwave monitoring system for composite material performance under load-environment coupling includes: a stress loading regulation component, a water circulation component, a dielectric constant monitoring component and a displacement control component, wherein both ends of the composite material are loaded on the stress loading regulation component, and the stress loading regulation component can perform constant stress or variable stress loading on the composite material, wherein the composite material is a non-conductive fiber reinforced composite material such as glass fiber, basalt fiber, aramid fiber, etc., and the material structure is in the form of a rod or a plate, the water circulation component is installed on the stress loading regulation component, and the composite material passes through the water circulation component, and the water circulation component is used to simulate the use environment of the composite material, wherein the water circulation component supports regulating the salt water concentration, temperature and humidity in the use environment of the composite material according to the actual environment; the dielectric constant monitoring component is installed on the stress loading regulation component, and the dielectric constant monitoring component is used to detect the change in the dielectric constant of the composite material; the displacement control component is installed on the stress loading regulation component, and the displacement control component drives the dielectric constant monitoring component and the water circulation component to move synchronously in a straight line.

[0069] The composite material may be in the form of a plate or a column. The present invention may be used to perform tensile load environment coupling loading on non-conductive composite rods or composite plates such as glass fiber, basalt fiber, and aramid fiber.

[0070] In a specific implementation manner, the stress loading control component includes: a stress fixing base 1-1, a first fixing bracket 1-2, a second fixing bracket 1-3, a stress driving component, an anchor 1-5, a force sensor 1-6 and a stress controller 1-7.

[0071] The stress fixing base 1-1 is arranged horizontally; the first fixing bracket 1-2 and the second fixing bracket 1-3 are symmetrically installed at the two ends of the upper surface of the stress fixing base 1-1; the stress driving component is installed on the stress fixing base 1-1 and is arranged on the side of the second fixing bracket 1-3; one end of the anchor 1-5 is installed on the first fixing bracket 1-2, and the other end of the anchor 1-5 is installed on the stress driving component, and the two ends of the composite material are installed in the two ends of the anchor 1-5; the force sensor 1-6 is installed on the side of the first fixing bracket 1-2 and on the anchor 1-5; the stress controller 1-7 is respectively electrically connected to the force sensor 1-6 and the stress driving component; the stress driving component supports and drives the anchor 1-5 on the same end side to move horizontally.

[0072] Among them, components such as stress controller 1-7 and anchor 1-5 are prior art, and all controllers in this application are prior art, which is a controller system of prior art.

[0073] In a specific implementation manner, the stress drive assembly includes: a servo motor 1-42 support 1-41, a servo motor 1-42, a first gear 1-43, a second gear 1-44, a screw 1-45 and a support plate 1-46; the servo motor 1-42 support 1-41 is installed on the surface of the stress fixed base 1-1; the servo motor 1-42 is installed on the servo motor 1-42 support 1-41; the upper and lower ends of the second gear 1-44 are respectively meshed with the first gear 1-43, and the second gear 1-44 is connected to the servo motor 1-42 through a coupling. The motor 1-42 is connected; the two screw rods 1-45 are arranged in parallel, and one end of the two screw rods 1-45 is respectively installed in the center of the two first gears 1-43; two threaded holes are arranged on the support plate 1-46, and the two threaded holes are respectively adapted to the two screw rods 1-45, and the end of the anchor 1-5 away from the first fixed bracket 1-2 is arranged on the end side of the support plate 1-46 away from the first fixed bracket 1-2, and the composite material is installed on the end of the anchor 1-5 away from the first fixed bracket 1-2 through the support plate 1-46.

[0074] Among them, when the servo motor 1-42 drives the second gear 1-44 to rotate, the second gear 1-44 drives the two first gears 1-43 to rotate, and the two first gears 1-43 respectively drive the corresponding screws 1-45 to rotate, the support plate 1-46 moves along the horizontal direction of the screw 1-45 and drives the two ends of the anchor 1-5 to be relatively close or far away.

[0075] In a specific embodiment, the water circulation component comprises:

[0076] A target water pipe 3-1, wherein the target water pipe 3-1 is arranged above the stress fixing base 1-1, one end of the target water pipe 3-1 is blocked by a first silicone plug, and the other end of the target water pipe 3-1 is blocked by a third silicone plug, the composite material passes through the first silicone plug, the target water pipe 3-1 and the third silicone plug in sequence, and the target water pipe 3-1 is installed in a target water pipe 3-1 insulation sleeve;

[0077] An electric heating tube 3-2, an electric heating belt 3-21 is installed on the outer wall of the electric heating tube 3-2, an electric heating belt 3-21 insulation sleeve is arranged on the outer wall of the electric heating belt 3-21, and the electric heating belt 3-21 insulation sleeve is installed on the first electric heating fixed support and the second electric heating fixed support;

[0078] A temperature controller 3-3, wherein the temperature controller 3-3 is mounted on the temperature controller 3-3 support, wherein the temperature controller 3-3 support is mounted on the upper surface of the stress fixing base 1-1, wherein the temperature controller 3-3 is electrically connected to the electric heating belt 3-21 and the temperature sensor, and wherein the temperature sensor is mounted in the target water pipe 3-1;

[0079] A first hose 3-4, a second hose 3-5 and a third hose 3-6, one end of the first hose 3-4 is connected to one end of the electric heating pipe 3-2, the other end of the first hose 3-4 is connected to a circulating water pump 3-9, the other end of the circulating water pump 3-9 is connected to one end of the second hose 3-5, the other end of the second hose 3-5 is connected to the end side wall of one end of the target water pipe 3-1 through a first tee, one end of the third hose 3-6 is connected to the other end of the electric heating pipe 3-2, and the other end of the third hose 3-6 is connected to the end side wall of the other end of the target water pipe 3-1 through a third tee;

[0080] The first hose 3-4 is provided with a first hose 3-4 insulation sleeve, the second hose 3-5 is provided with a second hose 3-5 insulation sleeve, the third hose 3-6 is provided with a third hose 3-6 insulation sleeve, and the circulating water pump 3-9 is electrically connected to the temperature controller 3-3;

[0081] A water level monitoring pipe 3-7, which is vertically installed above the target water pipe 3-1 and connected to the target water pipe 3-1 through a second tee, and a second silicone plug is provided at the end of the water level monitoring pipe 3-7;

[0082] A drain valve 3-10 and a water tank 3-8 are provided on the electric heating pipe 3-2 and on the same side as the third hose 3-6. The fourth three-way is connected to the electric heating pipe 3-2 and the third hose 3-6. A drain valve 3-10 is provided at the other end of the fourth three-way, and a water tank 3-8 is provided below the drain valve 3-10. The temperature sensor supports detecting the temperature in the target water pipe 3-1. When the temperature in the target water pipe 3-1 detected by the temperature sensor is higher than the required temperature, the heating belt is stopped from heating until the temperature in the target water pipe 3-1 drops to the required temperature range. The heating belt heats and controls the temperature of the circulating water within the required temperature range. If the temperature in the target water pipe 3-1 is lower than the required temperature, the heating belt is heated.

[0083] In a specific implementation manner, the dielectric constant monitoring component includes:

[0084] A vector network analyzer 2-1, wherein the vector network analyzer 2-1 is mounted on the stress fixing base 1-1 via an analyzer support;

[0085] A resonant cavity 2-2, wherein the resonant cavity 2-2 is installed at a position on the composite material of the anchor 1-5 where the water circulation component is not installed, the resonant cavity 2-2 is sleeved on the outer surface of the composite material, a support pile 2-4 is installed on the outer wall of the resonant cavity 2-2, and the other end of the support pile 2-4 is installed on the displacement control component, and the displacement control component drives the resonant cavity 2-2 to move on the composite material through the support pile 2-4;

[0086] A waveguide coupler 2-3, wherein the waveguide coupler 2-3 is installed on the resonant cavity 2-2 and is adapted to the resonant cavity 2-2, wherein the upper end port of the waveguide coupler 2-3 is a microwave input port, and the lower end port of the waveguide coupler 2-3 is a microwave output port, and the composite material runs through two ports of the waveguide coupler 2-3 in the horizontal left and right directions;

[0087] The vector network analyzer 2 - 1 is electrically connected to the waveguide coupler 2 - 3 via the microwave input port and the microwave output port of the waveguide coupler 2 - 3 .

[0088] In a specific implementation manner, the displacement control component includes:

[0089] A fixed platform 4-1, the fixed platform 4-1 is installed in parallel with the stress fixed base 1-1, and the fixed platform 4-1 is supported and installed on the stress fixed base 1-1 by two fixed piles;

[0090] A slide 4-2, a pulley 4-7 is arranged on the bottom surface of the slide 4-2, a track adapted to the pulley 4-7 is arranged on the fixed platform 4-1, the slide 4-2 is slidably connected and installed on the fixed platform 4-1, the bottoms of the first electric heating fixed support and the second electric heating fixed support are installed on the upper surface of the slide 4-2, and the bottoms of the support piles 2-4 are installed on the slide 4-2;

[0091] A mobile driving component, the output end of which is connected to the slide 4-2, and the mobile driving component supports and drives the slide 4-2 to move horizontally, and at the same time, the pulley 4-7 moves synchronously in the track.

[0092] In a specific implementation manner, the mobile drive component includes:

[0093] A displacement controller 4-3 and a displacement motor 4-4, wherein the displacement controller 4-3 is electrically connected to the displacement motor 4-4, and the displacement motor 4-4 is installed on the stress fixed base 1-1 through a displacement installation pile;

[0094] A conversion joint 4-5, the conversion structure is installed at the output end of the displacement motor 4-4;

[0095] A lead screw 4-6, one end of which is mounted on the conversion joint 4-5, and the other end of which is threadedly connected to the slide 4-2;

[0096] When the displacement motor 4-4 drives the lead screw 4-6 to rotate through the adapter structure, the lead screw 4-6 drives the slide 4-2 to move on the fixed platform 4-1.

[0097] In an embodiment of the present invention, the stress loading and regulating component is responsible for applying constant / variable load prestress to the composite material sample, so that the composite material is under a constant or variable load level. The water circulation component provides a high-temperature aging environment for the composite material under a specific type of aqueous solution medium. The dielectric constant monitoring component is used to perform real-time online monitoring of the composite material, collect the dielectric constant of the composite material after different aging times, and evaluate the moisture content and internal damage status of the composite material. The mobile drive component is used to automatically control the position of the high-temperature water circulation module, and according to the set dielectric constant monitoring time, the left and right movement control of the water circulation component is achieved by the forward and reverse rotation of the motor.

[0098] In terms of setting, monitoring and regulating prestress, the stress controller 1-7 can set the size of the prestress to be loaded. During the long-term loading process, the stress level is reduced due to creep relaxation of the composite rod / plate and the anchoring section of the anchor 1-5. The stress controller 1-7 can monitor the reduction amplitude of the prestress loaded by the force sensor 1-6 in real time. When the reduction amplitude of the prestress reaches the set value, the stress controller 1-7 sends a start command to the servo motor 1-42. The servo motor 1-42 operates according to the command, driving the second gear 1-44 and the first gear 1-43 to rotate, thereby rotating the screw 1-45, and further driving the support plate 1-46 to apply force to the anchor 1-5. The increased prestress is captured again by the force sensor 1-6 and fed back to the stress controller 1-7. The program set in the stress controller 1-7 determines whether to send a forward or reverse signal to the servo motor 1-42.

[0099] In terms of temperature setting, monitoring and control, after setting the heating temperature program, the temperature controller 3-3 energizes the electric heating belt 3-21 to start heating, and the temperature controller 3-3 energizes the circulating water pump 3-9 to make the solution in all water pipes flow, thereby heating the solution. The temperature sensor senses the change of water temperature in real time, and the water temperature signal is fed back to the temperature controller 3-3 through the temperature sensor wire. When the water temperature rises to the set value, the temperature controller 3-3 turns off the electric heating belt 3-21 and the circulating water pump 3-9 and stops heating. When the water temperature drops below the set value, the controller turns on the electric heating belt 3-21 and the circulating water pump 3-9 again to start heating.

[0100] In terms of dielectric constant monitoring, the vector network analyzer 2-1 can be set to perform regular frequency sweep measurements to monitor changes in the dielectric constant of the sample over time or other conditions.

[0101] In terms of displacement control, the start and stop time, speed and other parameters of the displacement controller 4-3 are set according to the set dielectric constant monitoring time, and the forward and reverse signals are sent to the displacement control displacement motor 4-4 through the displacement control line, driving the screw 4-6 to rotate, so as to realize the simultaneous left and right movement of the coupler of the water circulation component and the dielectric constant monitoring component.

[0102] In a specific implementation manner, all water pipes and heating pipes of the present invention can be selected from PTFE pipes, titanium pipes, quartz pipes, stainless steel pipes, aluminum pipes, and copper pipes with good corrosion resistance and temperature resistance according to the type of solution.

[0103] In a specific implementation manner, all the hoses of the present invention can be selected from silicone tubes, PVC tubes, and TPEE tubes with good elasticity and deformability.

[0104] In a specific implementation manner, the electric heating belt 3-21 can be selected from one of glass fiber heating belts, carbon fiber heating belts, and silicone rubber heating belts with good flexibility.

[0105] A method for microwave monitoring of composite material performance under load-environment coupling is applied to the above-mentioned microwave monitoring system for composite material performance under load-environment coupling, and comprises the following steps:

[0106] Installation and anchoring: Cut a preset length of composite material and anchor it in the anchor 1-5 on the stress loading and regulating component, and the stress load conditions can be adjusted by the stress controller 1-7;

[0107] Injecting solution: After adding the pre-made solution into the water circulation component, the water circulation component is driven to heat the internal circulating solution until it reaches a preset temperature, so that the environment in the water circulation component reaches the preset environmental standard;

[0108] By introducing the solution into the target water pipe 3-1 from the top of the water level monitoring pipe 3-7, the liquid in the target water pipe 3-1 is circulated by the water pump, and the top of the water level monitoring pipe 3-7 is blocked by the third silicone plug.

[0109] After the solution is injected, on the anchored composite material, a portion of the composite material is within the target water pipe 3 - 1 , and the remaining portion is not within the target water pipe 3 - 1 .

[0110] At this time, the electromagnetic parameters of the composite material in a dry state can be measured through the resonant cavity 2-2 and the waveguide coupler 2-3 in the dielectric constant monitoring component;

[0111] The composite material in the target water pipe 3-1 is divided into measurement sections. According to the moving direction of the target water pipe 3-1, the composite material is divided into a first measurement section, a second measurement section, ... and an nth measurement section.

[0112] After the first measuring section of the composite material stays in the water circulation component in the target water pipe 3-1 for a first preset time, the water circulation component and the dielectric constant monitoring component are driven to move by the mobile driving component at the same time, until the first measuring section of the composite material stays within the detection range of the dielectric constant monitoring component and the second measuring section is still in the water circulation component, and the resonance frequency of the material in a wet state is measured within the first preset time period;

[0113] After the second measuring section of the composite material stays in the water circulation component in the target water pipe 3-1 for the second preset time, the water circulation component and the dielectric constant monitoring component are simultaneously driven to move by the mobile driving component until the second measuring section of the composite material stays within the detection range of the dielectric constant monitoring component and the third measuring section is still in the water circulation component, and the resonant frequency of the material in a wet state within the second preset time period is measured, and so on until the resonant frequency of the nth measuring section in a wet state is measured.

[0114] The dielectric constant monitoring component determines whether the tested section of the composite material has internal damage when used in the preset environment based on the detected data. The judgment is based on the data obtained from the vector network analyzer test, analyzing the resonant frequency, the change rate of the real part and the imaginary part of the dielectric constant, and the increase in the water absorption rate of the material usually leads to changes in the above three factors:

[0115] (1) The resonant frequency is inversely proportional to the square root of the product of the material's permittivity (dielectric constant) and magnetic permeability. Therefore, if the dielectric constant increases while the magnetic permeability remains constant, the resonant frequency will theoretically decrease. This is because the increased dielectric constant makes the resonance condition more difficult to meet, requiring a lower frequency to achieve the same electromagnetic field standing wave pattern.

[0116] (2) Increase in the real part of the dielectric constant: When the material absorbs water, the polarity of the water molecules will enhance the polarization ability of the material, thereby increasing the real part of the dielectric constant. This is because water molecules have a permanent dipole moment and can be polarized in an external electric field, resulting in an increase in the overall polarization of the material. In addition, the free volume inside the material may increase after absorbing water, which also helps to increase the real part of the dielectric constant.

[0117] (3) Increase in the imaginary part of the dielectric constant: The imaginary part of the dielectric constant is related to the absorption and loss of electromagnetic wave energy by the material. After absorbing water, the water molecules and other polar groups inside the material will increase energy loss because they will dissipate part of the energy in the form of heat in the electromagnetic field. This loss is usually manifested as dielectric loss, that is, the reduction of energy during the propagation of electromagnetic waves in the material. Therefore, an increase in water absorption will lead to an increase in the imaginary part of the dielectric constant, indicating that the material's ability to absorb electromagnetic waves is enhanced.

[0118] As the water absorption rate of the material increases, the above three factors will change regularly, and the changes will show a certain data stability over time. If the change in the dielectric constant is different from the variation in the stable water absorption state, it is judged that there is damage inside.

[0119] In a specific implementation manner, the calculation method of the dielectric constant variation of each measurement segment includes the following contents:

[0120] Water absorption rate of composite material Wt It can be obtained by setting up horizontal comparison samples for testing, and the calculation formula is as follows:

[0121]

[0122] m t is the mass of the composite material after absorbing water at time t, and m0 is the mass of the composite material in a dry state without absorbing water.

[0123] According to the test data of the vector network analyzer, the resonant frequency f of the composite material after absorbing water at time t can be calculated by parameter inversion. t , the real part of the dielectric constant ε 1t and imaginary part ε 2t , the resonant frequency f0 in the unabsorbed state, the real part of the dielectric constant ε 10 and imaginary part ε 20 , then the relationship between water absorption and the three factors is as follows:

[0124]

[0125] They respectively represent the functional relationship between the resonant frequency, the real part of the dielectric constant, and the imaginary part of the dielectric constant and the water absorption rate as they change over time. The above-mentioned related data can be measured by setting up experiments, and the specific form of the function can be obtained after calculation and analysis to obtain an empirical formula. The empirical formula can be used to evaluate the water absorption rate of various types of non-conductive composite materials. And whether damage occurs inside the composite material can be judged based on whether the measured electromagnetic parameters have a sudden change.

[0126] The specific principles of the method in this embodiment are:

[0127] A rectangular or cylindrical microwave resonant cavity 2-2 is constructed, and the size and shape of the resonant cavity 2-2 are designed according to the cross-sectional shape and size of the composite material to be tested.

[0128] like Figure 4 In (a), the resonant cavity 2-2 is placed outside the composite material sample to be tested, and a waveguide coupler 2-3 matching the resonant cavity 2-2 is designed to transmit microwave signals. Figure 4(b) and 4(c) in the figure show a four-port resonant cavity 2-2 coupler, in which the upper and lower ports are microwave input and output ports respectively, and the left and right ports are embedded with the composite material sample to be tested. (b) shows the basic types of incident, reflected, and transmitted microwave signals inside the four-port resonant cavity 2-2 coupler; (c) shows the schematic diagram of the incident, reflected, and projected microwave signals collected from Port 1 / 2 after the four-port resonant cavity 2-2 coupler is embedded with the sample to be tested. The microwave resonant cavity 2-2 is used as a sensor. The resonant cavity 2-2 has a specific resonant frequency, which is related to the dielectric properties of non-conductive composite materials such as glass fiber.

[0129] The composite material sample is passed through the resonant cavity 2-2 of the coupler to ensure that microwaves can penetrate the sample. The microwave signal is introduced into and led out of the resonant cavity 2-2 through the waveguide coupler 2-3, and good electromagnetic coupling is formed between the waveguide coupler 2-3 and the resonant cavity 2-2.

[0130] A microwave signal is input into the resonant cavity 2-2 through the waveguide coupler 2-3, and the resonant frequency f and the dielectric constant are measured. When the moisture content of the composite material changes, its dielectric properties change, resulting in changes in the resonant frequency and dielectric constant of the resonant cavity 2-2.

[0131] Monitor the changes in resonant frequency and dielectric constant, calculate the moisture content of the composite material through a pre-established calibration curve or mathematical model, and determine whether damage has occurred inside the composite material through a sudden change in dielectric properties.

[0132] The present invention is based on the resonant cavity 2-2 coupler monitoring scheme adopted by the transmission line theory, which can quickly detect slight changes in the moisture content of the composite material. The method does not need to destroy the sample and can perform online monitoring.

[0133] The technical means adopted by the present invention is very sensitive to the change of the dielectric properties of the material and therefore has a higher measurement accuracy.

[0134] The water circulation component adopted in the present invention consumes less solution mass, is easy to replace and adjust, and has good experimental convenience.

[0135] The invention has a simple design and can be used to conduct experiments on a single composite material, and can also be used to conduct experiments on multiple composite materials through an extended design, and has good scalability.

[0136] The present invention can select a suitable water circulation component according to the solution type and temperature conditions required for the aging experiment, and has good feasibility.

[0137] The silicone plug sealing solution adopted in the present invention can better meet the need of sealing the solution to prevent leakage. Silicone rubber has good high and low temperature resistance and corrosion resistance and has good universality.

[0138] The following points need to be explained:

[0139] (1) The drawings of the embodiments of the present invention only relate to the structures related to the embodiments of the present invention, and other structures may refer to the general design.

[0140] (2) For the sake of clarity, in the drawings used to describe the embodiments of the present invention, the thickness of the layers or regions is exaggerated or reduced, that is, these drawings are not drawn according to the actual scale. It is understood that when an element such as a layer, film, region or substrate is referred to as being "on" or "under" another element, the element may be "directly" "on" or "under" the other element or there may be intermediate elements.

[0141] (3) In the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other to obtain new embodiments.

[0142] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A microwave monitoring system for composite material performance under load-environment coupling, characterized in that: include: A stress loading regulating component, on which both ends of the composite material are loaded, and the stress loading regulating component can load the composite material with constant stress or variable stress, A water circulation component, wherein the water circulation component is mounted on the stress loading regulating component, the composite material passes through the water circulation component, and the water circulation component is used to simulate the use environment of the composite material, wherein the water circulation component supports regulating the salt water concentration, temperature and humidity in the use environment of the composite material according to the actual environment; A dielectric constant monitoring component, the dielectric constant monitoring component is installed on the stress loading and regulating component, and the dielectric constant monitoring component is used to detect the change in the dielectric constant of the composite material; A displacement control component is installed on the stress loading regulation component, and the displacement control component drives the dielectric constant monitoring component and the water circulation component to move synchronously in a straight line.

2. The microwave monitoring system for composite material performance under load-environment coupling according to claim 1 is characterized in that: The stress loading control component comprises: A stress fixing base, wherein the stress fixing base is arranged horizontally; A first fixing bracket and a second fixing bracket, wherein the first fixing bracket and the second fixing bracket are symmetrically mounted at two ends of an upper surface of the stress fixing base; A stress driving component, the stress driving component is mounted on the stress fixing base and arranged on the side of the second fixing bracket; An anchor, one end of the anchor is mounted on the first fixing bracket, the other end of the anchor is mounted on the stress driving component, and both ends of the composite material are mounted in both ends of the anchor; A force sensor, the force sensor being mounted on the first fixing bracket side and on the anchor; A stress controller, the stress controller is respectively connected to the force sensor and the stress driving component by telecommunication; Wherein, the stress driving component supports and drives the anchor on the same end side to move horizontally.

3. The microwave monitoring system for composite material performance under load-environment coupling according to claim 2 is characterized in that: The stress driving component comprises: A servo motor support, the servo motor support being mounted on the surface of the stress fixing base; A servo motor, wherein the servo motor is mounted on the servo motor support; A first gear and a second gear, wherein upper and lower ends of the second gear are respectively meshed with the first gear, and the second gear is connected to the servo motor through a coupling; Screw rods, two of the screw rods are arranged in parallel, and one end of the two screw rods is respectively installed at the center of the two first gears; A support plate, wherein two threaded holes are arranged on the support plate, and the two threaded holes are respectively adapted to the two screw rods, and an end of the anchor away from the first fixing bracket is arranged on the end side of the support plate away from the first fixing bracket, and the composite material passes through the support plate and is installed on the end of the anchor away from the first fixing bracket; When the servo motor drives the second gear to rotate, the second gear drives the two first gears to rotate, and the two first gears respectively drive the corresponding screws to rotate, the support plate moves along the horizontal direction of the screw and drives the two ends of the anchor to move closer or farther away from each other.

4. The microwave monitoring system for composite material performance under load-environment coupling according to claim 3 is characterized in that: The water circulation component comprises: A target water pipe, the target water pipe is arranged above the stress fixing base, one end of the target water pipe is blocked by a first silicone plug, the other end of the target water pipe is blocked by a third silicone plug, the composite material passes through the first silicone plug, the target water pipe and the third silicone plug in sequence, and the target water pipe is installed in a target water pipe insulation sleeve; An electric heating tube, an electric heating belt is installed on the outer wall of the electric heating tube, an electric heating belt insulation sleeve is arranged on the outer wall of the electric heating belt, and the electric heating belt insulation sleeve is installed on the first electric heating fixed support and the second electric heating fixed support; A temperature controller, the temperature controller is mounted on the temperature controller support, the temperature controller support is mounted on the upper surface of the stress fixing base, the temperature controller is electrically connected to the electric heating belt and the temperature sensor, and the temperature sensor is mounted in the target water pipe; A first hose, a second hose and a third hose, one end of the first hose is connected to one end of the electric heating pipe, the other end of the first hose is connected to a circulating water pump, the other end of the circulating water pump is connected to one end of the second hose, the other end of the second hose is connected to the end side wall of one end of the target water pipe through a first tee, one end of the third hose is connected to the other end of the electric heating pipe, and the other end of the third hose is connected to the end side wall of the other end of the target water pipe through a third tee; Wherein, the first hose is provided with a first hose insulation sleeve, the second hose is provided with a second hose insulation sleeve, the third hose is provided with a third hose insulation sleeve, and the circulating water pump is electrically connected to the temperature controller; A water level monitoring pipe, which is vertically installed above the target water pipe and connected to the target water pipe through a second tee, and a second silicone plug is provided at the end of the water level monitoring pipe; A drain valve and a water tank are provided on the electric heating pipe and on the same side as the third hose. The fourth three-way connection connects the electric heating pipe and the third hose. A drain valve is provided at the other end of the fourth three-way connection, and a water tank is provided below the drain valve.

5. The microwave monitoring system for composite material performance under load-environment coupling according to claim 4 is characterized in that: The dielectric constant monitoring component comprises: A vector network analyzer, wherein the vector network analyzer is mounted on the stress fixing base via an analyzer support; A resonant cavity, wherein the resonant cavity is installed at a position of the composite material on the anchor where the water circulation component is not installed, the resonant cavity is sleeved on the outer surface of the composite material, a support pile is arranged on the outer wall of the resonant cavity, the other end of the support pile is installed on the displacement control component, and the displacement control component drives the resonant cavity to move on the composite material through the support pile; A waveguide coupler, wherein the waveguide coupler is mounted on the resonant cavity and adapted to the resonant cavity, wherein the upper end port of the waveguide coupler is a microwave input port, and the lower end port of the waveguide coupler is a microwave output port, and the composite material runs through two ports of the waveguide coupler in horizontal left and right directions; The vector network analyzer is electrically connected to the waveguide coupler through a microwave input port and a microwave output port of the waveguide coupler.

6. The microwave monitoring system for composite material performance under load-environment coupling according to claim 5 is characterized in that: The displacement control component comprises: A fixed platform, the fixed platform is installed parallel to the stress fixing base, and the fixed platform is supported and installed on the stress fixing base through two fixed piles; A slide, a pulley is arranged on the bottom surface of the slide, a track adapted to the pulley is arranged on the fixed platform, the slide is slidably connected and installed on the fixed platform, the bottoms of the first electric heating fixed support and the second electric heating fixed support are installed on the upper surface of the slide, and the bottom of the support pile is installed on the slide; A mobile driving component, the output end of which is connected to the slide, the mobile driving component supports and drives the slide to move horizontally, and at the same time, the pulley moves synchronously in the track.

7. The microwave monitoring system for composite material performance under load-environment coupling according to claim 6 is characterized in that: The mobile driving component comprises: A displacement controller and a displacement motor, wherein the displacement controller is electrically connected to the displacement motor, and the displacement motor is installed on a stress fixed base through a displacement mounting pile; A conversion joint, wherein the conversion structure is installed at the output end of the displacement motor; A lead screw, one end of which is mounted on the conversion joint, and the other end of which is threadedly connected to the slide; When the displacement motor drives the lead screw to rotate through the adapter structure, the lead screw drives the slide table to move on the fixed table.

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