A method for detecting strength performance of a fiber reinforced composite material

Abstract

The application provides a kind of fiber reinforced composite strength performance detection method, wherein the fiber reinforced composite strength performance detection method includes: selecting several composite material sample plates, using high temperature aging method or high-low temperature alternating aging method treatment;Sound insulation of each composite material sample plate is measured;The ultimate tensile strength of each composite material sample plate is measured;According to the sound insulation of each composite material sample plate and the ultimate tensile strength, the first relationship between the ultimate tensile strength and the sound insulation of the composite material sample plate is obtained;Select the composite material product to be tested, and the ultimate tensile strength of the composite material product to be tested is obtained by measuring the sound insulation of the composite material product to be tested combined with the first relationship.The technical scheme provided by the application realizes qualitative evaluation on the strength performance of fiber reinforced composite product by irregularly detecting and analyzing the sound insulation of fiber reinforced composite product, without destructive testing on the product.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of composite material performance detection, and particularly relates to a fiber-reinforced composite material strength performance detection method. BACKGROUND

[0002] The fiber-reinforced composite material refers to a material formed by compounding fiber and its products as reinforcing materials and matrix materials through a certain molding process, that is, an ideal structural material and a functional material with excellent performance, which is widely used in military facilities, weapon equipment, aerospace and other fields.

[0003] Quality problems or damage causes affecting the use performance of fiber-reinforced composite material components or products mainly come from two aspects: one is that product quality problems such as dark bubbles and delamination formed in the process develop in the use process, or the material inside the product separates under the action of external force, eventually forming a gap or fracture, which can be generally classified as physical damage; the other is that the molecular structure changes caused by long-term action of external force and internal force in the use process of the product eventually form quality damage affecting the use performance of the product, for example, ultraviolet or high-temperature aging. Generally, it can be classified as molecular damage. The damage of the gap or fracture type can be detected by ultrasonic method and the like, so as to realize the analysis and evaluation of the use performance of the fiber-reinforced composite material components or products. The molecular damage type quality problem is crucial to the use performance of the components or products. At present, the optical fiber is mainly used to detect the material performance and quality problems of large-size components at home and abroad, but there is still a lack of effective method for small-size components. SUMMARY

[0004] The present application aims to at least solve one of the technical problems existing in the prior art or related art.

[0005] Therefore, one object of the present application is to provide a fiber-reinforced composite material strength performance detection method.

[0006] Another object of the present application is to provide a fiber-reinforced composite material strength performance detection device.

[0007] In order to achieve the above object, the technical scheme of the present application provides a fiber-reinforced composite material strength performance detection method, comprising:

[0008] Select a plurality of composite material samples, and treat the samples by using a high-temperature aging method or a high-low temperature alternating aging method; measure the sound insulation of each composite material sample; measure the ultimate tensile strength of each composite material sample; obtain a first relationship between the ultimate tensile strength and the sound insulation of each composite material sample according to the sound insulation and the ultimate tensile strength of each composite material sample; select a composite material product to be tested, and obtain the ultimate tensile strength of the composite material product to be tested by measuring the sound insulation of the composite material product to be tested and combining the first relationship.

[0009] Further, the selecting a plurality of composite material samples and treating the samples by using a high-temperature aging method or a high-low temperature alternating aging method specifically includes: treating different composite material samples by a first temperature for different time; or treating different composite material samples by alternating between a second temperature and a third temperature for different time.

[0010] Further, the obtaining a first relationship between the ultimate tensile strength and the sound insulation of each composite material sample according to the sound insulation and the ultimate tensile strength of each composite material sample specifically includes: establishing a coordinate system with the ultimate tensile strength of the composite material sample as the Y coordinate and the sound insulation of the composite material sample as the X coordinate; marking coordinate points in the coordinate system according to the sound insulation and the ultimate tensile strength data of each composite material sample; and obtaining the first relationship by using an image method or a data fitting method according to the coordinate points of each composite material sample.

[0011] Further, the first relationship is Y=aX+b; where Y is the ultimate tensile strength, the unit is MPa, a and b are constants, X is the sound insulation, the unit is decibel (dB).

[0012] Further, the first temperature is 150℃, and the second temperature is greater than the third temperature.

[0013] Another object of the present application is to provide a fiber-reinforced composite material strength performance detection device, which comprises: a sound emitting chamber; a sound receiving chamber adjacent to the sound emitting chamber; a sound emitter arranged in the sound emitting chamber; and a sound receiver arranged in the sound receiving chamber; wherein a side wall between the sound emitting chamber and the sound receiving chamber is provided with a mounting support plate for mounting a composite material product to be tested, and the composite material product to be tested and the mounting support plate separate the sound receiving chamber and the sound emitting chamber.

[0014] Further, the device further comprises: two sound insulation doors hingedly connected to the side walls of the sound receiving chamber and the sound emitting chamber, respectively, for opening or closing the sound receiving chamber and the sound emitting chamber.

[0015] Further, the mounting support plate is provided with a through hole and a plurality of first connecting holes arranged around the through hole, and the composite material product to be tested is mounted on the mounting support plate through the first connecting holes and covers the through hole.

[0016] Furthermore, it also includes: an elastic seal, which is arranged around the through hole between the mounting support plate and the composite product to be tested; the composite product to be tested is provided with a second connecting hole, the first connecting hole is a countersunk hole, and the composite product to be tested is connected to the mounting support plate by bolts.

[0017] Furthermore, it also includes: a sealing strip, which is arranged in the through hole, and the sealing strip is in a closed ring shape and the outer contour of the sealing strip is in contact with the inner wall of the through hole; a pressing plate, which is provided with a third connecting hole that cooperates with the first connecting hole, and an avoidance hole is provided on the pressing plate; wherein, the outer contour of the composite product to be tested is in contact with the inner wall of the sealing strip, and pressing plates are provided on both sides of the mounting support plate, and the two pressing plates are mounted to the mounting support plate by bolts, and squeeze the sealing strip, so that the sealing strip is deformed in the plane direction of the composite product to be tested, thereby fixing the composite product to be tested.

[0018] The beneficial effect of the technical solution provided by the embodiment of the present invention is that the present invention can detect and evaluate the strength performance of fiber-reinforced composite materials in a laboratory or on a construction site without destroying the product.

[0019] By irregularly testing and analyzing the sound insulation performance of fiber-reinforced composite material samples or products, it is possible to evaluate their strength performance without having to conduct destructive testing on the products. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A flow chart showing a method for testing the strength properties of a fiber-reinforced composite material according to an embodiment of the present invention is shown;

[0021] Figure 2 A flow chart showing a method for testing the strength properties of a fiber-reinforced composite material according to an embodiment of the present invention is shown;

[0022] Figure 3 A schematic structural diagram of a fiber reinforced composite material strength performance testing device according to an embodiment of the present invention is shown;

[0023] Figure 4 A schematic structural diagram of a fiber reinforced composite material strength performance testing device according to an embodiment of the present invention is shown;

[0024] Figure 5 A schematic structural diagram of a fiber reinforced composite material strength performance testing device according to an embodiment of the present invention is shown;

[0025] Figure 6 A schematic structural diagram of a pressing plate according to an embodiment of the present invention is shown.

[0026] The symbols in the figure are explained as follows:

[0027] 10 sound emitting chamber, 20 sound receiving chamber, 11 sound emitter, 21 sound receiver, 30 mounting support plate, 40 composite material product to be tested, 50 sound insulation door, 31 through hole, 32 first connecting hole, 60 sealing strip, 70 pressing plate, 71 third connecting hole, 72 avoiding hole. DETAILED DESCRIPTION

[0028] In order to make the objects, technical solutions and advantages of the present application clearer, the following will further describe the embodiments of the present application and its beneficial effects in detail with reference to the accompanying drawings.

[0029] As shown in the drawings, one embodiment of the present application provides a method for detecting strength performance of fiber reinforced composite material, comprising the following steps: Figure 1

[0030] Step S110: selecting a plurality of composite material sample plates and processing them by high temperature aging method or high-low temperature alternating aging method;

[0031] In this step, the purpose of selecting a plurality of composite material sample plates is to obtain multiple sample plates, and the multiple composite material sample plates are processed by high temperature aging or high-low temperature alternating aging method, so as to obtain multiple composite material sample plates with different ultimate tensile strengths, so as to provide multiple sets of data for establishing the functional relationship between the ultimate tensile strength and the sound insulation quantity of the composite material sample plates.

[0032] Step S120: measuring the sound insulation quantity of each composite material sample plate;

[0033] Step S130: measuring the ultimate tensile strength of each composite material sample plate;

[0034] In steps S120 and S130, the sound insulation quantity of different composite material sample plates is detected respectively, and the sound insulation quantity corresponding to each composite material sample plate is recorded. In detail, after the multiple composite material sample plates are processed by high temperature or high-low temperature alternating processing, the aging degrees of the composite material sample plates are different due to different processing conditions, which leads to different ultimate tensile strengths and sound insulation quantities among the different composite material sample plates. It should be noted that for the composite material sample plates processed by high temperature aging or high-low temperature alternating aging method, the sound insulation quantity is measured first and then the ultimate tensile strength is measured, so as to ensure the accuracy of the sound insulation quantity detection. Because when the ultimate tensile strength is measured, a large tensile force needs to be applied to the composite material sample plate, which will cause certain damage to the composite material sample plate, thereby changing the sound insulation quantity of the composite material sample plate. The specification of the composite material sample plate is 500mm×500mm.

[0035] Step S140: obtaining a first relationship between the ultimate tensile strength and the sound insulation quantity of the composite material sample plate according to the sound insulation quantity and the ultimate tensile strength of each composite material sample plate; ​

[0036] In this step, each composite sample corresponds to a sound insulation amount and an ultimate tensile strength, and the aging degree of the composite sample is different from the corresponding ultimate tensile strength. By summarizing the sound insulation amount corresponding to the different ultimate tensile strength of the composite sample, the first relationship between the ultimate tensile strength and the sound insulation amount of the composite sample can be obtained, and the corresponding relationship between the ultimate tensile strength and the sound insulation amount of the composite sample is established.

[0037] Step S150: Selecting a composite material product to be tested, and obtaining the ultimate tensile strength of the composite material product to be tested by measuring the sound insulation amount of the composite material product to be tested combined with the first relationship.

[0038] In this step, the composite material whose ultimate tensile strength needs to be detected is selected, and the ultimate tensile strength of the composite material product to be tested can be calculated by the first relationship by measuring the sound insulation amount of the composite material product to be tested, without the need to apply a limit tensile force to the composite material product to be tested, so as to avoid damaging the composite material product to be tested.

[0039] Further, the high-temperature aging or high-low temperature alternating aging method for obtaining different strength composite sample specifically includes the following steps:

[0040] The first temperature is treated for different time for different composite samples;

[0041] Or the second temperature and the third temperature are alternately treated for different time for different composite samples.

[0042] In this step, the high-temperature aging method is to treat different composite samples by the first temperature for different time, so that each composite sample corresponds to a different length of high-temperature treatment time. Understandably, the longer the length of time of the composite sample treated by high temperature, the greater the aging degree of the composite sample and the smaller the ultimate tensile strength. Therefore, different composite samples are treated by the first temperature for different time, so that different composite samples have different aging degrees, thereby obtaining composite samples with different ultimate tensile strengths.

[0043] The high-low temperature alternating aging method is to alternately treat different composite samples between the second temperature and the third temperature for different time. Understandably, the principle of obtaining composite samples with different ultimate tensile strengths by the high-low temperature alternating aging method is the same as that of the high-temperature aging method.

[0044] Further, as shown in Figure 2 According to the sound insulation amount and the ultimate tensile strength of each composite sample, the first relationship between the ultimate tensile strength and the sound insulation amount of the composite sample specifically includes:

[0045] Step S210: establishing a coordinate system with the ultimate tensile strength of the composite material sample as the Y coordinate and the sound insulation amount of the composite material sample as the X coordinate;

[0046] Step S220: marking a coordinate point in the coordinate system according to the sound insulation amount and the ultimate tensile strength data of each composite material sample;

[0047] Step S230: obtaining a first relationship by using an image method or a data fitting method according to the coordinate point of each composite material sample.

[0048] Specifically, since each composite material sample has a corresponding ultimate tensile strength and sound insulation amount after being subjected to high-temperature aging treatment or high-low temperature cross-aging treatment, the ultimate tensile strength and sound insulation amount corresponding to the composite material samples with different aging degrees are different. Therefore, the ultimate tensile strength of the composite material sample is taken as the Y coordinate, and the sound insulation amount of the composite material sample is taken as the X coordinate to establish a coordinate system. The purpose is to generate different coordinate points of the ultimate tensile strength and sound insulation amount of each composite material sample in the coordinate system by the coordinate system, and to realize the establishment of the relationship between the ultimate tensile strength and the sound insulation amount by using a data processing method.

[0049] Specifically, the data processing method is specifically an image method or a data fitting method.

[0050] The image method visually displays the experimental data on the coordinate plane according to the function relationship between the independent variable and the dependent variable. The basic requirements for drawing the image on the coordinate paper are: 1. The scale of the quantity coordinate axis should be appropriate; 2. There should be a sufficient number of drawing points; 3. The drawn image should pass through as many drawing points as possible. In the case of a curve, a rough sketch can be drawn first according to the distribution position of most of the drawing points, and then a smooth curve can be connected.

[0051] Data fitting, also known as curve fitting, is a way of representing existing data by substituting it into a mathematical formula.

[0052] The first relationship is Y=aX+b, where Y is the ultimate tensile strength, a and b are constants, and X is the sound insulation amount in decibels (dB).

[0053] The first temperature is 150°C, and the high-temperature aging method is to place the composite material sample in an environment of 150°C for a period of time. To obtain composite material samples with different ultimate tensile strengths, different time periods can be selected. Understandably, the first temperature of 150°C is only one implementation of the high-temperature aging method, and the first temperature can also be set to other temperature values, such as 160°C, 155°C, 140°C, 100°C, etc.

[0054] The second temperature is greater than the third temperature. For example, the second temperature is 90℃ and the third temperature is -20℃, or the second temperature is 150℃ and the third temperature is -40℃, etc.

[0055] The specific implementation of the high-low temperature alternating aging method is to place the composite sample at the second temperature for a period of time (for example, 2 hours or 3 hours), and then gradually cool it from the second temperature to the third temperature, and then place it at the third temperature for a period of time (for example, 2 hours or 3 hours, etc.).

[0056] As shown in Figure 3 and Figure 4 The second aspect of the present application provides a fiber-reinforced composite strength performance detection device, which comprises a sound emitting chamber 10, a sound receiving chamber 20, a sound emitter 11, and a sound receiver 21. The sound receiving chamber 20 is adjacent to the sound emitting chamber 10. The sound emitter 11 is arranged in the sound emitting chamber 10 for emitting sound at a specified frequency. The sound emitter 11 emits sound waves, displays and records the frequency of the sound waves, and the frequency range is 0-5000 Hz. Experimental data shows that the sound insulation data measured when the sound wave frequency is 0-1000 Hz is the best. The sound receiver 21 is arranged in the sound receiving chamber 20, and the sound receiver 21 can realize automatic sound collection, recording and storage. The side wall between the sound emitting chamber 10 and the sound receiving chamber 20 is provided with a mounting support plate 30, which is used for mounting the composite product 40 to be tested. The composite product 40 to be tested and the mounting support plate 30 separate the sound receiving chamber 20 and the sound emitting chamber 10. The fiber-reinforced composite strength performance detection device detects the sound insulation of each fiber-reinforced composite sample, which can also refer to the laboratory and field measurement standards for measuring the sound insulation performance of the sound insulation room in GB / T 19885-2005, so as to obtain the sound insulation at multiple frequencies.

[0057] Further, the fiber-reinforced composite strength performance detection device further comprises a sound insulation door 50, the number of which is two, which are respectively hinged to the side walls of the sound receiving chamber 20 and the sound emitting chamber 10, and are used for opening or closing the sound receiving chamber 20 and the sound emitting chamber 10. The sound insulation door 50 is used for personnel access. The sound insulation door 50 needs to achieve a sound insulation of 50db or more.

[0058] The detection device can realize the sound insulation strength performance detection of a 500mm×500mm fiber-reinforced composite sample, without the need for a sound insulation professional test laboratory.

[0059] Further, the mounting support plate 30 is provided with a through hole 31 and a plurality of first connecting holes 32 arranged around the through hole 31, wherein the first connecting hole 32 is a through hole penetrating the mounting support plate, and the diameter of the first connecting hole 32 is 16 mm, which can be used for mounting the composite material sample plate. The composite material product 40 to be tested is mounted on the mounting support plate 30 through the first connecting hole 32 and covers the through hole 31. The sound wave of a specified frequency emitted by the sound emitter 11 passes through the composite material product 40 to be tested and is received by the sound receiver 21. The incident sound intensity (It) can be obtained according to the sound emitter 11, and the transmitted sound intensity (Ii) can be obtained according to the data received by the sound receiver 21, so as to obtain the sound insulation amount of the composite material product 40 to be tested.

[0060] In another specific embodiment, the composite material product 40 to be tested is provided with a second connecting hole, and the first connecting hole 32 is a counterbore, and the composite material product 40 to be tested is connected with the mounting support plate 30 through a bolt. The first connecting hole 32 is a counterbore, so as to improve the sound insulation effect of the mounting support plate 30.

[0061] Specifically, the sound insulation amount refers to the ratio of the transmitted sound intensity (Ii) to the incident sound intensity (It), and the calculation formula is as follows:

[0062]

[0063] It should be further pointed out that the specific size of the through hole 31 matches the size of the composite material product 40 to be tested, so as to realize the detection of the strength performance of composite materials of different sizes.

[0064] The material of the mounting support plate 30 is structural steel or concrete, and the sound insulation amount of the mounting support plate 30 reaches more than 30 db.

[0065] Further, the composite material strength performance detection device further comprises an elastic sealing member, which is arranged between the mounting support plate 30 and the composite material product 40 to be tested around the through hole 31. The elastic sealing member can realize the sealed connection between the mounting support plate 30 and the composite material product 40 to be tested, so as to avoid the sound wave emitted by the sound emitter 11 from passing through the gap between the mounting support plate 30 and the composite material product 40 to be tested, and interfering with the sound wave data received by the sound receiver 21.

[0066] As Figure 5 and Figure 6In another specific embodiment, as shown, in order to solve the problem that the sound insulation amount of the composite material product 40 to be tested is inaccurate due to the overlapping part between the composite material product 40 to be tested and the mounting support plate 30, a sealing strip 60 is arranged in the through hole 31, the sealing strip 60 is in a closed ring shape, the outer contour of the sealing strip 60 is attached to the inner wall of the through hole 31 to ensure the sealing connection between the sealing strip 60 and the mounting support plate 30, and the inner side wall of the sealing strip 60 is attached to the outer contour of the composite material product 40 to be tested, so that the mounting support plate 30, the sealing strip 60 and the composite material product 40 to be tested are all in sealing connection to form an integral whole to separate the sound emitting chamber 10 and the sound receiving chamber 20, and two pressing plates 70 are further arranged to firmly fix the composite material product 40 to be tested in the sealing strip 60, the pressing plate 70 is provided with a third connecting hole 71 matched with the first connecting hole 32, the two pressing plates 70 are bolted to the mounting support plate 30, and the two pressing plates 70 are pressed against the sealing strip 60 by the pre-tightening force of the bolts, so that the sealing strip 60 is deformed in the plane direction of the composite material product 40 to be tested and presses against the composite material product 40 to be tested, thereby fixing the composite material product 40 to be tested, and the pressing plate 70 is provided with an avoiding hole 72, the purpose of the avoiding hole 72 is to avoid any obstacles between the sound emitter 11 and the composite material product 40 to be tested, so that the sound waves emitted by the sound emitter 11 are directly transmitted through the composite material product 40 to be tested after being transmitted through the air, thereby reducing the measurement error of the sound insulation amount of the composite material.

[0067] During the use of the material, the sound insulation amount of the fiber reinforced composite material under the same condition is detected by the fiber reinforced composite material strength performance detection device, or the sound insulation amount of the fiber reinforced composite material product is detected, and the strength of the material is evaluated through the change of the sound insulation amount.

[0068] The beneficial effects of the present application are as follows: the present application can detect and evaluate the strength performance of the fiber reinforced composite material in the laboratory or on the engineering site without damaging the product.

[0069] The strength performance of the fiber reinforced composite material is evaluated by irregularly detecting and analyzing the sound insulation amount of the fiber reinforced composite material sample or product, without destructive detection of the product.

[0070] In the present application, the terms "first", "second", "third" are only used for descriptive purpose, and should not be understood as indicating or implying relative importance. The term "multiple" refers to two or more, unless otherwise explicitly limited. The terms "mount", "connect", "connection", "fix", and the like should be interpreted broadly, for example, "connection" can be fixed connection, or detachable connection, or integral connection; "connection" can be direct connection, or indirect connection through intermediate medium. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0071] In the description of the present application, it should be understood that the terms "upper", "lower", "left", "right", "front", "back", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or unit referred to must have a particular direction, be constructed and operated in a particular orientation, therefore, should not be understood as a limitation on the present application.

[0072] In the description of the present application, the terms "one embodiment", "some embodiments", "a specific embodiment", and the like, mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0073] The above is only the preferred embodiment of the present application, and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for testing the strength performance of fiber reinforced composite materials, characterized in that: include: Select several composite material samples and treat them using high temperature aging method or high and low temperature alternating aging method; First, measuring the sound insulation value of each composite material sample after treatment; Then measuring the ultimate tensile strength of each of the composite material samples after treatment; Obtaining a first relationship between the ultimate tensile strength and the sound insulation of each composite material sample according to the sound insulation and ultimate tensile strength of each composite material sample; Selecting a composite material product to be tested, and obtaining the ultimate tensile strength of the composite material product to be tested by measuring the sound insulation of the composite material product to be tested and combining the first relationship; The method of selecting a plurality of composite material samples and treating them with a high temperature aging method or a high and low temperature alternating aging method specifically includes: Treat different composite material samples at the first temperature for different times; Alternatively, different composite material samples may be subjected to alternating treatments between the second temperature and the third temperature for different periods of time.

2. The method for testing the strength performance of fiber-reinforced composite materials according to claim 1, characterized in that: Obtaining a first relationship between the ultimate tensile strength and the sound insulation of each composite material sample according to the sound insulation and ultimate tensile strength of each composite material sample specifically includes: A coordinate system is established with the ultimate tensile strength of the composite material sample as the Y coordinate and the sound insulation value of the composite material sample as the X coordinate; Mark the coordinate points in the coordinate system according to the sound insulation and ultimate tensile strength data of each composite material sample; The first relationship is obtained by adopting an image method or a data fitting method according to the coordinate points of each composite material sample.

3. The method for testing the strength performance of fiber-reinforced composite materials according to claim 1, characterized in that: The first relational expression is Y=aX+b; Among them, Y is the ultimate tensile strength, the unit is MPa, a and b are constants, and X is the sound insulation, the unit is decibel dB.

4. The composite material strength performance testing method according to claim 1, characterized in that: The first temperature ranges from 70°C to 150°C; The second temperature is greater than the third temperature.

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