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

Abstract

The application provides a composite material performance microwave monitoring system under load environment coupling, and relates to the technical field of composite materials.The system comprises a stress loading regulation component, a water circulation component, a dielectric constant monitoring component and a displacement control component, two ends of the composite material are loaded on the stress loading regulation component, the stress loading regulation component can load constant stress or variable stress on the composite material, the water circulation component is installed on the stress loading regulation component, and the water circulation component is used for simulating the use environment of the composite material; the dielectric constant monitoring component is installed on the stress loading regulation component, and the dielectric constant monitoring component is used for detecting the dielectric constant change amount of the composite material; and the displacement control component is installed on the stress loading regulation component, the stress loading regulation component, the dielectric constant monitoring component and the water circulation component move linearly, and whether the composite material has internal damage can be judged according to the monitored data.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of composite materials, in particular to a microwave monitoring system for performance of composite materials under coupling of load and environment. BACKGROUND

[0002] Composite materials are used in the fields of aviation, aerospace, military, communication, sports, construction, etc. due to their high specific strength, high specific modulus, low density, corrosion resistance, and strong design. In various civil engineering working conditions such as ocean, ground, and deep ground, composite material rods / plates are common product forms. Under certain working stress conditions, composite rods / plates usually accompany certain humidity, salt, temperature, etc., and then performance degradation occurs. At present, there are few studies on the durability of composite materials under the combined action of corrosion ions, hydrolysis, high temperature and humidity accelerated aging, etc. under tensile prestress loading. There is still a lack of effective non-destructive online monitoring means for changes in water content and internal damage of composite materials (glass fiber, basalt fiber, aramid fiber, etc. non-conductive fiber reinforced composite materials) during long-term service. SUMMARY

[0003] To solve one of the technical problems in the prior art, the present application provides a microwave monitoring system for performance of composite materials under coupling of load and environment, which simulates the coupling of load and environment to which the composite material is subjected under natural environmental conditions. The technical solution is as follows:

[0004] A microwave monitoring system for performance of composite materials under coupling of load and environment, comprising:

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

[0006] A water circulation component, the water circulation component is installed on the stress loading and 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 regulation of 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 amount of the dielectric constant of the composite material;

[0008] A displacement control assembly is installed on the stress loading regulation assembly, and the displacement control assembly drives the dielectric constant monitoring assembly and the water circulation assembly to move linearly synchronously.

[0009] Optionally, the stress loading regulation assembly comprises:

[0010] A stress fixing base is horizontally arranged;

[0011] A first fixing support and a second fixing support are symmetrically arranged at two ends of the upper surface of the stress fixing base;

[0012] A stress driving assembly is arranged on the stress fixing base and at the side of the second fixing support;

[0013] An anchor is arranged at one end of the first fixing support and at the other end of the stress driving assembly, and two ends of the composite material are arranged in the two ends of the anchor;

[0014] A force sensor is arranged at the side of the first fixing support and on the anchor;

[0015] A stress controller is electrically connected to the force sensor and the stress driving assembly respectively;

[0016] The stress driving assembly supports the horizontal movement of the anchor at the same end.

[0017] Optionally, the stress driving assembly comprises:

[0018] A servo motor support is arranged on the surface of the stress fixing base;

[0019] A servo motor is arranged on the servo motor support;

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

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

[0022] A support plate is arranged with two threaded holes, and the two threaded holes are respectively matched with the two screw rods, one end of the anchor away from the first fixing support is arranged at the end of the support plate away from the first fixing support, and the composite material is arranged at one end of the anchor away from the first fixing support through the support plate;

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

[0024] Optionally, the water circulation assembly comprises:

[0025] A target water pipe is arranged above the stress fixing base, one end of the target water pipe is blocked by a first silica gel plug, the other end of the target water pipe is blocked by a third silica gel plug, the composite material passes through the first silica gel plug, the target water pipe and the third silica gel plug in sequence, and the target water pipe is arranged in a target water pipe heat preservation sleeve.

[0026] An electric heating pipe is arranged, an electric heating belt is arranged on the outer wall of the electric heating pipe, an electric heating belt heat preservation sleeve is arranged on the outer wall of the electric heating belt, and the electric heating belt heat preservation sleeve is arranged on the electric heating first fixing support and the electric heating second fixing support.

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

[0028] A first hose, a second hose and a third hose are arranged, one end of the first hose is connected with one end of the electric heating pipe, the other end of the first hose is connected with a circulating water pump, the other end of the circulating water pump is connected with one end of the second hose, the other end of the second hose is connected with the end part side wall of one end of the target water pipe through a first three-way joint, one end of the third hose is connected with the other end of the electric heating pipe, and the other end of the third hose is connected with the end part side wall of the other end of the target water pipe through a third three-way joint.

[0029] The first hose is provided with a first hose heat preservation sleeve, the second hose is provided with a second hose heat preservation sleeve, the third hose is provided with a third hose heat preservation sleeve, and the circulating water pump is electrically connected with the temperature controller.

[0030] A water level monitoring pipe is arranged vertically above the target water pipe and connected with the target water pipe through a second three-way joint, and a second silica gel plug is arranged at the end part of the water level monitoring pipe.

[0031] A drain valve and a water tank are arranged on the electric heating pipe and on the same side of the third hose, a fourth three-way joint is arranged on the electric heating pipe and connected with the third hose, the other end of the fourth three-way joint is provided with the drain valve, and the water tank is arranged below the drain valve.

[0032] Optionally, the dielectric constant monitoring assembly comprises:

[0033] a vector network analyzer, which is installed on the stress fixing base through an analyzer support;

[0034] a resonant cavity, which is installed on the anchorage device at a position where the composite material is not provided with the water circulation assembly, the resonant cavity is sleeved on the outer surface of the composite material, support piles are arranged on the outer wall of the resonant cavity, the other ends of the support piles are installed on the displacement control assembly, and the displacement control assembly drives the resonant cavity to move on the composite material through the support piles;

[0035] a waveguide coupler, which is installed on the resonant cavity and is adapted to the resonant cavity, the upper end port of the waveguide coupler is a microwave input port, the lower end port of the waveguide coupler is a microwave output port, and the composite material penetrates through the two ports of the waveguide coupler in the horizontal left-right direction;

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

[0037] Optionally, the displacement control assembly comprises:

[0038] a fixed table, which is installed in parallel on the stress fixing base, and is supported and installed on the stress fixing base through two fixed piles;

[0039] a sliding table, the bottom surface of the sliding table is provided with a pulley, the fixed table is provided with a track adapted to the pulley, the sliding table is slidingly connected and installed on the fixed table, the bottom of the electric heating first fixed support and the electric heating second fixed support is installed on the upper surface of the sliding table, and the bottom of the support pile is installed on the sliding table;

[0040] a movement driving assembly, the output end of the movement driving assembly is connected with the sliding table, and the movement driving assembly supports driving the sliding table to move horizontally, and at the same time, the pulley moves synchronously in the track.

[0041] Optionally, the movement driving assembly comprises:

[0042] a displacement controller and a displacement motor, the displacement controller is electrically connected with the displacement motor, and the displacement motor is installed on the stress fixing base through a displacement installation pile;

[0043] a conversion joint, which is installed on the output end of the displacement motor;

[0044] A screw rod is installed on one end of the conversion joint, and the other end of the screw rod is threadedly connected with the sliding table;

[0045] When the displacement motor drives the screw rod to rotate through the conversion structure, the screw rod drives the sliding table to move on the fixed table.

[0046] The technical scheme provided by the embodiment of the present application has at least the following beneficial effects:

[0047] The monitoring scheme of the resonant cavity coupler based on the transmission line theory can quickly detect the slight change of the water content of the composite material. The method can be used for online monitoring without damaging the sample.

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

[0049] The technical means adopted by the present application is very sensitive to the change of the dielectric properties of the material, so it has high measurement accuracy.

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

[0051] The present application has a simple design, which can be used for single composite material experiment, and can also be used for multiple composite material experiment through expansion design, and has good expansibility.

[0052] The present application can select appropriate water circulation assembly according to the required solution type and temperature condition of the aging test, and has good implementability.

[0053] The silica gel plug sealing scheme adopted by the present application can better meet the needs of solution sealing without leakage. The silicone rubber has good high and low temperature resistance and corrosion resistance, and has good universality. DETAILED DESCRIPTION

[0054] In order to more clearly illustrate the technical scheme in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0055] Figure 1 The structural diagram of the device provided by the present application is shown in the figure;

[0056] Figure 2 The stress loading regulation and control assembly provided by the present application is shown in the figure;

[0057] Figure 3A water circulation assembly provided by the present application is shown in the figure;

[0058] Figure 4 A dielectric constant monitoring assembly provided by the present application is shown in the figure;

[0059] Figure 5 A displacement control assembly provided by the present application is shown in the figure.

[0060] Reference signs:

[0061] 1-1, stress fixing base; 1-2, first fixing support; 1-3, second fixing support; 1-41, servo motor support; 1-42, servo motor; 1-43, first gear; 1-44, second gear; 1-45, screw rod; 1-46, support plate; 1-5, anchor device; 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, water 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 solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be described clearly and completely below in combination with the drawings of the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the described embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without any creative effort belong to the scope of protection of the present application.

[0066] Unless otherwise defined, the technical or scientific terms used in the present invention shall have the usual meaning understood by persons of ordinary skill in the field to which the present invention belongs. The words "first", "second" and similar terms 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", "an" or "the" do not indicate a quantity limitation, but rather indicate the presence of at least one. Words such as "include" or "comprise" mean that the elements or objects preceding 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" and "back" 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 control component, a water circulation component, a dielectric constant monitoring component and a displacement control component. Both ends of the composite material are loaded on the stress loading control component. The stress loading control component can apply constant stress or variable stress to 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 control component, and the composite material passes through the water circulation component. 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 control 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 control 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 can be in the form of a plate or a column. The present invention can 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 embodiment, 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 horizontally arranged; the first fixing support 1-2 and the second fixing support 1-3 are symmetrically arranged at the two ends of the upper surface of the stress fixing base 1-1; the stress driving assembly is arranged on the stress fixing base 1-1 and at the side of the second fixing support 1-3; one end of the anchor 1-5 is arranged on the first fixing support 1-2, and the other end of the anchor 1-5 is arranged on the stress driving assembly; the two ends of the composite material are arranged in the two ends of the anchor 1-5; the force sensor 1-6 is arranged at the side of the first fixing support 1-2 and on the anchor 1-5; the stress controller 1-7 is electrically connected to the force sensor 1-6 and the stress driving assembly respectively; the stress driving assembly supports the horizontal movement of the anchor 1-5 at the same end side.

[0072] The stress controller 1-7, the anchor 1-5 and other components are prior art, and all the controllers of the present application are prior art, which are controller systems of prior art.

[0073] In a specific embodiment, the stress driving assembly comprises 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 rod 1-45 and a support plate 1-46; the servo motor 1-42 support 1-41 is arranged on the surface of the stress fixing base 1-1; the servo motor 1-42 is arranged on the servo motor 1-42 support 1-41; the upper and lower ends of the second gear 1-44 are respectively engaged with the first gear 1-43, and the second gear 1-44 is connected to the servo motor 1-42 through a shaft coupling; two screw rods 1-45 are arranged in parallel, and one end of each screw rod 1-45 is arranged at the center of a first gear 1-43; two threaded holes are arranged on the support plate 1-46, and the two threaded holes are respectively matched with the two screw rods 1-45; one end of the anchor 1-5 away from the first fixing support 1-2 is arranged on the side of the support plate 1-46 away from the first fixing support 1-2, and the composite material is arranged at one end of the anchor 1-5 away from the first fixing support 1-2.

[0074] 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 screw rods 1-45 to rotate, so that the support plate 1-46 moves along the horizontal direction of the screw rod 1-45 and drives the two ends of the anchor 1-5 to relatively approach or move away.

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

[0076] A 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 silica gel plug, the other end of the target water pipe 3-1 is blocked by a third silica gel plug, the composite material passes through the first silica gel plug, the target water pipe 3-1 and the third silica gel plug in sequence, and the target water pipe 3-1 is installed in a target water pipe 3-1 heat preservation sleeve;

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

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

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

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

[0081] A water level monitoring pipe 3-7 is vertically installed above the target water pipe 3-1 and connected with the target water pipe 3-1 through a second three-way pipe, and a second silica gel plug is arranged at the end part of the water level monitoring pipe 3-7;

[0082] Drain valve 3-10 and sink 3-8, the fourth three-way is provided on the electric heating tube 3-2 and with the third hose 3-6 side, the fourth three-way is connected electric heating tube 3-2 and the third hose 3-6, the other end of the fourth three-way is provided drain valve 3-10, the drain valve 3-10 below is provided with water tank 3-8;The temperature sensor supports the temperature of the target water pipe 3-1, when the temperature sensor detects the temperature of the target water pipe 3-1 is higher than the required temperature, stop heating belt heating, until the temperature of the target water pipe 3-1 is reduced to the required temperature range, heating belt heating and control the temperature of the circulating water in the required temperature range, if the temperature of the target water pipe 3-1 is lower than the required temperature, heating belt heating.

[0083] In a specific embodiment, the dielectric constant monitoring assembly comprises:

[0084] Vector network analyzer 2-1, the vector network analyzer 2-1 is installed on the stress fixing base 1-1 through the analyzer support;

[0085] Resonant cavity 2-2, the resonant cavity 2-2 is installed on the anchor 1-5 on the position where the composite material is not provided with the water circulation assembly, the resonant cavity 2-2 is sleeved on the outer surface of the composite material, the support pile 2-4 is arranged on the outer wall of the resonant cavity 2-2, the other end of the support pile 2-4 is installed on the displacement control assembly, the displacement control assembly drives the resonant cavity 2-2 to move on the composite material through the support pile 2-4;

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

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

[0088] In a specific embodiment, the displacement control assembly comprises:

[0089] Fixed table 4-1, the fixed table 4-1 is installed in parallel on the stress fixing base 1-1, and the fixed table 4-1 is supported and installed on the stress fixing base 1-1 through two fixed piles;

[0090] A sliding table 4-2 is arranged on the fixed table 4-1, and a pulley 4-7 is arranged on the bottom surface of the sliding table 4-2; the electric heating first fixed support and the electric heating second fixed support are arranged on the upper surface of the sliding table 4-2; and the bottom of the support pile 2-4 is arranged on the sliding table 4-2.

[0091] A movement driving assembly is connected with the sliding table 4-2, and the movement driving assembly supports the horizontal movement of the sliding table 4-2, and the pulley 4-7 moves synchronously in the track.

[0092] In a specific embodiment, the movement driving assembly comprises:

[0093] A displacement controller 4-3 and a displacement motor 4-4 are electrically connected, and the displacement motor 4-4 is arranged on the stress fixed base 1-1 through a displacement mounting pile.

[0094] A conversion joint 4-5 is arranged on the output end of the displacement motor 4-4.

[0095] A lead screw 4-6 is arranged on the conversion joint 4-5, and the other end of the lead screw 4-6 is threadedly connected with the sliding table 4-2.

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

[0097] In the embodiment of the application, the stress loading control assembly is responsible for constant / variable load pre-stress loading of the composite sample, so that the composite material is under constant or variable load level. The water circulation assembly provides a high-temperature aging environment for the composite material under a specific type of aqueous solution medium. The dielectric constant monitoring assembly is used for real-time online monitoring of the composite material, collecting the dielectric constant of the composite material after different aging times, and evaluating the water content and internal damage state of the composite material. The movement driving assembly is used for automatic control of 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 assembly is realized through 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 loaded prestress. During long-term loading, the prestress decreases due to the creep relaxation of the composite rod / plate and the anchoring segment of the anchorage 1-5. The stress controller 1-7 can monitor the decrease of the prestress loaded by the force sensor 1-6 in real time. When the decrease of the prestress reaches a 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 to drive the second gear 1-44 and the first gear 1-43 to rotate, thereby rotating the screw rod 1-45 and further driving the support plate 1-46 to apply force to the anchorage 1-5. The increased prestress is captured by the force sensor 1-6 again and fed back to the stress controller 1-7. The stress controller 1-7 sends a forward or reverse signal to the servo motor 1-42 according to the set program.

[0099] In terms of setting, monitoring and regulating temperature, after setting the heating temperature program, the temperature controller 3-3 powers on the electric heating belt 3-21 to start heating. The temperature controller 3-3 powers on 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. The water temperature signal is fed back to the temperature controller 3-3 through the temperature sensor wire. When the water temperature rises to a set value, the temperature controller 3-3 turns off the electric heating belt 3-21 and the circulating water pump 3-9 to stop heating. When the water temperature decreases below the set value, the controller turns on the electric heating belt 3-21 and the circulating water pump 3-9 to start heating again.

[0100] In terms of dielectric constant monitoring, the vector network analyzer 2-1 can be set to perform periodic sweep measurement to monitor the change of the dielectric constant of the sample over time or other conditions.

[0101] In terms of displacement control, the start-stop time and speed of the displacement controller 4-3 are set according to the set dielectric constant monitoring time. The forward and reverse signals are sent to the displacement motor 4-4 through the displacement control line to drive the lead screw 4-6 to rotate, thereby achieving the simultaneous left-right movement of the water circulation assembly and the coupler of the dielectric constant monitoring assembly.

[0102] In a specific embodiment, all the water pipes and heating pipes of the present application can be made of one of PTFE pipe, titanium pipe, quartz pipe, stainless steel pipe, aluminum pipe and copper pipe according to the type of the solution.

[0103] In a specific embodiment, all the hoses of the present application can be made of one of silicone tube, PVC tube and TPEE tube.

[0104] In a specific embodiment, the electric heating belt 3-21 can be selected from a glass fiber heating belt, a carbon fiber heating belt, and a silicone rubber heating belt.

[0105] A microwave monitoring method for the performance of composite materials under the coupling of load and environment, applied to the microwave monitoring system for the performance of composite materials under the coupling of load and environment, comprising the following steps:

[0106] Anchor installation: intercept the composite material of a predetermined length and anchor it in the anchor 1-5 on the stress loading control assembly. The stress controller 1-7 can be used to adjust the stress load conditions.

[0107] Solution injection: After the prepared solution is added to the water circulation assembly, the water circulation assembly is driven to heat the circulating solution inside until the preset temperature is reached, so that the environment in the water circulation assembly reaches the preset environmental standard.

[0108] The solution is introduced into the target water pipe 3-1 from the top of the water level monitoring pipe 3-7, and the liquid in the target water pipe 3-1 is circulated by the water pump. The top of the water level monitoring pipe 3-7 is sealed by the third silica gel plug.

[0109] After the solution is injected, a part of the composite material is in the target water pipe 3-1, and the rest is not in the target water pipe 3-1.

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

[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] When the first measurement section of the composite material stays in the water circulation assembly for a first predetermined time, the water circulation assembly and the dielectric constant monitoring assembly are moved by the moving drive assembly, until the first measurement section of the composite material stays in the detection range of the dielectric constant monitoring assembly, and the second measurement section is still in the water circulation assembly. The resonant frequency of the composite material in the wet state is measured in the first predetermined time period.

[0113] When the second measuring section of the composite material stays in the target water pipe 3-1 for a second preset time in the water circulation assembly, the water circulation assembly and the dielectric constant monitoring assembly are moved by the movement driving assembly until the second measuring section of the composite material stays in the detection range of the dielectric constant monitoring assembly and the third measuring section is also in the water circulation assembly. The resonant frequency of the material in the wet state is measured in the second preset time, and the resonant frequency of the material in the wet state of the nth measuring section is measured in the same way.

[0114] According to the data detected by the dielectric constant monitoring assembly, it is judged whether the measured section of the composite material has internal damage in the preset environment. The judgment is based on the data obtained by the vector network analyzer, the change rate of the resonant frequency, the real part and the imaginary part of the dielectric constant, and the increase of the water absorption rate of the material, which usually causes the change of the above three factors:

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

[0116] (2) Increase of the real part of the dielectric constant: After the material absorbs water, the polarity of the water molecules enhances 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 increase in free volume inside the material after water absorption also helps to increase the real part of the dielectric constant.

[0117] (3) Increase of 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 water absorption, the water molecules and other polar groups inside the material increase the energy loss, as they dissipate part of the energy in the form of heat in the electromagnetic field. This loss is usually manifested as dielectric loss, i.e. the reduction of energy during the propagation of electromagnetic waves in the material. Therefore, the increase of water absorption rate will lead to the increase of the imaginary part of the dielectric constant, indicating the enhancement of the absorption ability of the material to electromagnetic waves.

[0118] With the increase of the water absorption rate of the material, the above three factors will change regularly, and the change will show certain data stability with the increase of time. If the dielectric constant changes differently from the variation in the stable water absorption state, it is judged that there is internal damage.

[0119] In a specific embodiment, the calculation method of the dielectric constant change of each measuring section includes the following contents:

[0120] Water absorption rate of the composite material The test can be performed by setting a transverse contrast sample, and the calculation formula is as follows:

[0121] ;

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

[0123] According to the test data of the vector network analyzer, the resonance frequency of the composite material after absorbing water at t , the real part and the imaginary part of the dielectric constant, the resonance frequency of the composite material in a dry state without water absorption , the real part and the imaginary part of the dielectric constant can be calculated respectively by parameter inversion.

[0124] ;

[0125] ;

[0126] ;

[0127] , , respectively represent the functional relationship between the resonance frequency, the real part of the dielectric constant, the imaginary part of the dielectric constant and the water absorption rate under the change of time. The above related data can be measured by setting experiments, and the specific form of the function can be obtained after calculation and analysis, and the empirical formula is obtained. The empirical formula can be used to evaluate the water absorption rate of various types of non-conductive composite materials. And according to whether the measured electromagnetic parameters change suddenly or not, it can be judged whether damage occurs inside the composite material.

[0128] The specific principle of the method in this embodiment is:

[0129] 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 measured.

[0130] As shown in (a) of FIG. 2, Figure 4 The resonant cavity 2-2 is wrapped outside the composite material sample to be measured, and a waveguide coupler 2-3 matched with the resonant cavity 2-2 is designed for transmitting microwave signals. As shown in FIG. 2, Figure 4Fig. 4 (b) and 4 (c) show the four-port resonant cavity 2-2 coupler, wherein the upper and lower two ports are microwave input and output ports respectively, and the left and right two ports are embedded with the composite material sample to be measured, (b) is the basic type of incident, reflected and transmitted microwave signals in the four-port resonant cavity 2-2 coupler, and (c) is a schematic diagram of collecting incident, reflected and transmitted microwave signals from Port1 / 2 after embedding the sample to be measured in the four-port resonant cavity 2-2 coupler. The microwave resonant cavity 2-2 is used as a sensor, and the resonant cavity 2-2 has a specific resonant frequency, which is associated with the dielectric properties of the non-conductive composite material such as glass fiber.

[0131] The composite material sample is passed through the resonant cavity 2-2 of the coupler to ensure that the microwave can penetrate the sample. The microwave signal is introduced and introduced into the resonant cavity 2-2 through the waveguide coupler 2-3, and the waveguide coupler 2-3 and the resonant cavity 2-2 form good electromagnetic coupling.

[0132] The microwave signal is input to the resonant cavity 2-2 through the waveguide coupler 2-3, and the resonant frequency f and the dielectric constant are measured. When the water content of the composite material changes, the dielectric properties change, causing the resonant frequency and dielectric constant of the resonant cavity 2-2 to change.

[0133] The changes of the resonant frequency and the dielectric constant are monitored, and the water content of the composite material is calculated through the pre-established calibration curve or mathematical model, and whether the damage occurs inside the composite material is judged by the sudden change of the dielectric properties.

[0134] The monitoring scheme of the resonant cavity 2-2 coupler based on the transmission line theory adopted by the present application can quickly detect the slight change of the water content of the composite material. The method does not need to destroy the sample and can be monitored online.

[0135] The technical means adopted by the present application is very sensitive to the change of the dielectric properties of the material, so it has high measurement accuracy.

[0136] The water circulation assembly adopted by the present application consumes less solution mass, and is easy to replace and adjust, and has good experimental convenience.

[0137] The present application has a simple design, which can carry out experiments on a single composite material, and can also carry out experiments on multiple composite materials through expansion design, and has good expansibility.

[0138] The present application can select a suitable water circulation assembly according to the type and temperature condition of the solution required by the aging experiment, and has good implementability.

[0139] The silicone plug sealing scheme adopted by the present application can better meet the needs of solution sealing without leakage, and the silicone rubber has good high and low temperature resistance and corrosion resistance characteristics, and has good universality.

[0140] The following points need to be explained:

[0141] (1) The drawings of the embodiments of the present application only involve the structures involved in the embodiments of the present application, and other structures can be referred to the general design.

[0142] (2) In order to be clear, the thickness of the layer or area is enlarged or reduced in the drawings for describing the embodiments of the present application, that is, the drawings are not drawn according to the actual proportion. It can be understood that when an element such as a layer, a film, an area or a substrate is referred to as being located "on" or "under" another element, the element can be "directly" located "on" or "under" another element or there can be an intermediate element.

[0143] (3) In the case of no conflict, the embodiments of the present application and the features in the embodiments can be combined with each other to obtain new embodiments.

[0144] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and the protection scope of the present application should be subject to 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 and regulating assembly, on which both ends of the composite material are loaded, and on which the stress loading and regulating assembly can apply constant stress or variable stress to the composite material, and the stress loading and regulating assembly includes a stress fixing base, which is arranged horizontally; a water circulation assembly, the water circulation assembly being mounted on the stress loading and regulating assembly, the composite material passing through the water circulation assembly, the water circulation assembly being used to simulate the use environment of the composite material, wherein the water circulation assembly 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 in the stress loading control 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, the displacement control component being mounted on the stress loading control component and driving the dielectric constant monitoring component and the water circulation component to move linearly and synchronously; The water circulation component includes: a target water pipe, the target water pipe being arranged above the stress fixing base, one end of the target water pipe being sealed by a first silicone plug, the other end of the target water pipe being sealed by a third silicone plug, the composite material being sequentially passed through the first silicone plug, the target water pipe, and the third silicone plug, and the target water pipe being installed in a target water pipe insulation sleeve; An electric heating pipe, an electric heating belt installed on the outer wall of the electric heating pipe, an electric heating belt insulation sleeve is provided 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 being mounted on the temperature controller support, the temperature controller support being mounted on the upper surface of the stress fixing base, the temperature controller being electrically connected to the electric heating belt and a temperature sensor, the temperature sensor being mounted in the target water pipe; a first hose, a second hose, and a third hose, wherein 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, a first hose insulation sleeve is provided on the first hose, a second hose insulation sleeve is provided on the second hose, a third hose insulation sleeve is provided on the third hose, and the circulating water pump is electrically connected to the temperature controller; A water level monitoring pipe is vertically installed above the target water pipe and connected to the target water pipe through a second tee. 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 is connected to 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. The displacement control component includes: 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 provided on the bottom surface of the slide, a track adapted to the pulley is provided on the fixed platform, the slide is slidably connected and mounted on the fixed platform, and the bottoms of the first electrically heated fixed support and the second electrically heated fixed support are mounted on the upper surface of the slide; A mobile drive component, wherein the output end of the mobile drive component is connected to the slide, and the mobile drive component supports and drives the slide to move horizontally, and at the same time, the pulley moves synchronously in the track.

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 further includes: 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 is 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 assembly, and both ends of the composite material are mounted in both ends of the anchor; a load cell mounted on the first fixing bracket and on the anchor; A stress controller, the stress controller being electrically connected to the force sensor and the stress driving component; 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 includes: 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 the upper and lower ends of the second gear are respectively engaged with the first gear, and the second gear is connected to the servo motor via a coupling; Screws, wherein the two screws are arranged in parallel, and one end of the two screws is respectively installed in the center of the two first gears; a support plate, wherein two threaded holes are provided on the support plate, the two threaded holes are respectively adapted to the two screw rods, an end of the anchor away from the first fixing bracket is provided on the end 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.

4. The microwave monitoring system for composite material performance under load-environment coupling according to claim 3 is characterized in that: The dielectric constant monitoring component includes: A vector network analyzer, the vector network analyzer being mounted on the stress fixing base via an analyzer support; a resonant cavity, the resonant cavity being mounted on a position of the composite material on the anchor where the water circulation component is not mounted, the resonant cavity being sleeved on an outer surface of the composite material, a support pile being provided on an outer wall of the resonant cavity, and the other end of the support pile being mounted on a slide within the displacement control component; The displacement control component drives the resonant cavity to move on the composite material through the support pile; a waveguide coupler, the waveguide coupler being mounted on and adapted to the resonant cavity, the upper end port of the waveguide coupler being a microwave input port, the lower end port of the waveguide coupler being a microwave output port, and the composite material passing through the two ports in the horizontal left and right directions of the waveguide coupler; 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.

5. The microwave monitoring system for composite material performance under load-environment coupling according to claim 4 is characterized in that: The mobile drive assembly includes: A displacement controller and a displacement motor, wherein the displacement controller is electrically connected to the displacement motor, and the displacement motor is mounted on a stress fixing base via a displacement mounting pile; A conversion joint, the conversion joint being 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 conversion joint, the lead screw drives the slide table to move on the fixed table.

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