Evaluation method and detection device for porosity uniformity

Abstract

The invention discloses a porosity uniformity evaluation method and a detection device, and belongs to the technical field of material detection, the method comprises the following steps: collecting any one of the following ultrasonic detection data of a sample: first scanning based on an ultrasonic reflection contact method, third scanning based on an ultrasonic penetration method, and the porosity of the sample; calculating any one of the following evaluation indexes or a combination of the following evaluation indexes through the ultrasonic detection data: a first scan, a third scan and a uniformity coefficient of the porosity of the sample; and evaluating the uniformity of the sample through the evaluation index and the corresponding threshold value. The evaluation index is calculated for one or more ultrasonic detection data, and the uniformity of the sample or the reference block is quantitatively evaluated, so that the correctness and accuracy of the ultrasonic detection result of the porosity of the composite material workpiece are improved, missing detection and misjudgment are avoided, and the quality of the workpiece is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of material detection, and in particular to a porosity uniformity evaluation method and a detection device. Background Art

[0002] Composite materials have been installed and applied in large quantities in the fields of aerospace, transportation, energy, construction, etc. In order to ensure the quality of composite materials and safe use, non-destructive testing of composite materials is required during the manufacturing process of composite materials. Among them, quantitative detection and evaluation of porosity is an important subject of non-destructive testing of composite materials. The following two methods are mainly used: one method is to take samples from the edge margin of composite materials, and then prepare and observe the samples using optical microscopy. By observing the pore distribution of a certain section of the sample, the porosity content of the composite materials is indirectly evaluated; the other method is based on the ultrasonic principle, using the mathematical relationship between the change of ultrasonic signals and the pores to perform non-destructive testing on the porosity of composite materials. This method usually requires the setting of a comparison test block first, and then the porosity is evaluated through the comparison test block. The comparison block is a standard transfer material for porosity detection of composite parts based on the ultrasonic principle. The quality, porosity distribution uniformity and accuracy of the comparison block directly affect the accuracy of the ultrasonic porosity detection results of the parts, especially the porosity uniformity directly affects the correctness of the ultrasonic porosity detection results of the parts. The ultrasonic method obtains the porosity detection results in composite parts.

[0003] In order to solve the problem of ultrasonic porosity testing of composite parts with different testing scenarios and characteristics, and to improve the reliability of testing and the accuracy of test results, it is required to firstly adopt the applicable process simulation technology to prepare porosity comparison test blocks with different levels of difference; then, the uniformity of pore distribution in the prepared porosity comparison test blocks should be effectively evaluated. At present, there is still a lack of effective methods for evaluating porosity uniformity. Summary of the invention

[0004] In view of the above technical problems existing in the prior art, the present invention provides a porosity uniformity evaluation method and detection device, which evaluates the uniformity of the sample based on ultrasonic detection data.

[0005] The present invention discloses a method for evaluating porosity uniformity, comprising the following steps: collecting any of the following ultrasonic detection data of a sample: a first scan based on an ultrasonic reflection contact method, a third scan based on an ultrasonic penetration method, and the porosity of the sample; calculating any of the following evaluation indicators or a combination thereof through the ultrasonic detection data: a uniformity coefficient of the first scan, the third scan, and the porosity of the sample; and evaluating the uniformity of the sample through the evaluation indicators and corresponding thresholds.

[0006] Preferably, if the evaluation indication is greater than or equal to the corresponding threshold value, the sample passes the uniformity evaluation of the evaluation indicator.

[0007] Preferably, all evaluation indicators are greater than or equal to the corresponding thresholds, and the sample passes the uniformity evaluation.

[0008] Preferably, the evaluation index includes a uniformity coefficient, and a method for calculating the uniformity coefficient includes:

[0009] Calculating an average value based on the ultrasonic detection data;

[0010] Calculate the screening conditions according to the average value and the difference;

[0011] Calculating the number of detection points that meet the screening conditions;

[0012] The uniformity coefficient is calculated according to the proportion of the detection points.

[0013] Preferably, the method for calculating the uniformity coefficient of the first scan includes:

[0014] Get the data of the first scan, the matrix of the first scan is expressed as:

[0015]

[0016] Among them, U represents the matrix of the first scan, Represented as the i-th u Column, No. j u The amplitude of the detection position point of the line, m u Indicates the total number of columns of position points in the first scan, n u Indicates the total number of rows of position points in the first scan;

[0017] Calculate the average value of the first scan,

[0018]

[0019] in, Expressed as the average of the first scan;

[0020] The position points satisfying the first screening condition are counted to obtain a first number of detection points, wherein the first screening condition is expressed as: ΔU is the level difference of the first scanning amplitude;

[0021] According to the first detection point number, calculate the uniformity coefficient of the first scan:

[0022]

[0023] in, Expressed as the uniformity coefficient of the first scan.

[0024] Preferably, the method for calculating the uniformity coefficient of the third scan C includes:

[0025] Get the data for the third scan:

[0026]

[0027] Among them, G represents the matrix of the third scan, Represented as the i-th c Column, No. j c The amplitude of the line detection position point, m C Indicates the total number of columns of position points in the third scan, n c Indicates the total number of rows of position points in the third scan;

[0028] Compute the average of the third scan:

[0029]

[0030] in, Expressed as the average of the third scan;

[0031] The position points satisfying the third screening condition are counted to obtain a third number of detection points, wherein the third screening condition is expressed as: ΔG is the level difference of the third scanning amplitude;

[0032] According to the third detection point number, calculate the uniformity coefficient of the third scan:

[0033]

[0034] in, Expressed as the uniformity coefficient of the third scan.

[0035] Preferably, the method for calculating the uniformity coefficient of the sample porosity includes:

[0036] Get the matrix of sample porosity:

[0037]

[0038] Where D represents the matrix of sample porosity, Represented as the i-th d Column, No. j d The porosity value of the row, m d Indicates the total number of columns, n d is the total number of rows;

[0039] Calculate the average porosity:

[0040]

[0041] in, It is expressed as the average value of porosity;

[0042] The position points satisfying the fourth screening condition are counted to obtain a fourth number of detection points, wherein the fourth screening condition is expressed as: ΔD is the difference in porosity values;

[0043] According to the fourth detection point number, calculate the uniformity coefficient of porosity:

[0044]

[0045] in, Expressed as the uniformity coefficient of porosity.

[0046] Preferably, the sample is a composite material comparison test block or a composite material product.

[0047] The present invention also provides a detection device for implementing the above method, comprising a transducer, a first scanning unit, a third scanning unit, a porosity detection unit and an evaluation module;

[0048] The transducer is used to perform ultrasonic testing on the sample to obtain ultrasonic data;

[0049] The first scanning unit is used to obtain a first scan based on the ultrasound data;

[0050] The third scanning unit is used to obtain a third scan according to the ultrasound data;

[0051] The porosity detection unit is used to obtain the porosity of the sample according to the ultrasonic data;

[0052] The evaluation module is used to calculate the evaluation index according to the detection data; and to evaluate the uniformity of the sample according to the evaluation index and the corresponding threshold value.

[0053] Preferably, the assessment module is also used to save data and generate a test report.

[0054] Compared with the prior art, the beneficial effects of the present invention are: by calculating evaluation indicators for one or more ultrasonic detection data, and quantitatively evaluating the uniformity of samples and comparison test blocks, the uniformity of comparison test blocks is improved, the correctness and accuracy of ultrasonic detection results of the porosity of composite parts are improved, missed detection and misjudgment are avoided, and the quality of parts is ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 is a flow chart of the method for evaluating porosity uniformity of the present invention;

[0056] Figure 2A It is a detection schematic diagram of the ultrasonic reflection contact method;

[0057] Figure 2B It is a detection schematic diagram of ultrasonic reflection non-contact method;

[0058] Figure 2C It is a schematic diagram of the detection of ultrasonic penetration method;

[0059] Figure 3 It is a logic block diagram of the detection device of the present invention.

[0060] Markings in the figure: 1 transducer, 2 first scanning unit, 3 third scanning unit, 4 porosity detection unit, 5 evaluation module, 7 sample. DETAILED DESCRIPTION

[0061] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0063] To better illustrate the present invention, as shown in FIG2 , a common ultrasonic detection method is as follows:

[0064] Ultrasonic reflection contact method, see Figure 2A , the transducer 1 is in direct contact with the sample 7.

[0065] Ultrasonic reflection non-contact method, see Figure 2B There is a gap between the transducer 1 and the sample 7, and the ultrasonic wave μ0 enters the upper surface of the sample and is converted into μ i , which is converted into μ after reflection from the lower surface of the sample t , passes through the upper surface of the sample and is received by transducer 1.

[0066] Ultrasound penetration, see Figure 2C , which consists of two ultrasonic probes. The ultrasonic wave μ0 emitted by the upper ultrasonic probe enters the upper surface of the sample, which is recorded as μ i , after passing through the lower surface of the sample, is recorded as μ t , μ t The ultrasonic probe on the lower side receives the signal. The minimum scanning step can reach 0.5 mm, the signal-to-noise ratio of the ultrasonic C-scanning system 3 is not greater than 10%, and a water immersion or water spray coupling scanning method is adopted.

[0067] Ultrasonic porosity testing: Suitable porosity testing instruments and equipment can be selected to directly evaluate the porosity of the sample and record the results.

[0068] The above method is used to realize the ultrasonic A scan (first scan), ultrasonic B scan (second scan), ultrasonic C scan (third scan) and porosity detection of the composite material porosity comparison test block. Among them, the transducer 1 in the ultrasonic detection can select an ultrasonic probe suitable for composite material porosity detection, with a frequency between 1MHz-10MHz.

[0069] like Figure 1 As shown, the method for evaluating porosity uniformity of the present invention comprises the following steps:

[0070] Step 101: Collect any of the following ultrasonic testing data of the sample: a first scan A based on an ultrasonic reflection contact method, a third scan C based on an ultrasonic penetration method, and the porosity of the sample.

[0071] Step 102: Calculate any one of the following evaluation indicators or a combination thereof through the ultrasonic detection data:

[0072] Uniformity coefficient of the first scan, third scan, and sample porosity.

[0073] Step 103: Evaluate the uniformity of the sample using the evaluation index and the corresponding threshold.

[0074] By calculating the evaluation index for one or more ultrasonic test data, and quantitatively evaluating the uniformity of the sample and the comparison test block, the uniformity of the comparison test block is improved, and the correctness and accuracy of the ultrasonic test results of the porosity of the composite parts are improved, so as to avoid missed detection and misjudgment and ensure the quality of the parts.

[0075] The uniformity coefficient of the first scan A is calculated as follows:

[0076] Step 201: Obtain data of the first scan A. In the first scan A, the amplitude matrix U of each detection position point is as shown in Formula 1:

[0077]

[0078] in, Represented as the i-th u Column, No. j u The amplitude of the detection position point of the row, i u Represents the column of detected location points, j u Indicates the row of detected position points, m u Indicates the total number of columns of position points in the first scan, n u Indicates the total number of rows of position points in the first scan, m u 、n u The spacing between adjacent detection points is selected between 5 mm and 10 mm, which is determined by the size of the sample and the density of the first scanning detection points.

[0079] Step 202: Calculate the average value of the first scan The calculation method is shown in Formula 2:

[0080]

[0081] Step 203: Count the position points that meet the first screening condition to obtain the first detection point number N u .

[0082] The first filter condition is: If it satisfies N u =N u +1,N u The initial value of is 0, and ΔU is the amplitude difference of the porosity ultrasonic A-scan, which is determined by experiments according to the porosity ultrasonic A-scan assessment requirements.

[0083] Step 204: Calculate the uniformity coefficient of the first scan according to the first detection point number

[0084] The uniformity coefficient of the first scan is evaluated as follows: When the uniformity of the first scan of the sample meets the requirements, it passes the assessment. is the first uniformity threshold of the sample.

[0085] The uniformity coefficient of the third scan C is calculated as follows:

[0086] Step 301: Obtain data of the third scan C. The matrix G of the ultrasonic C scan values ​​of each detection position point is expressed as:

[0087]

[0088] In the formula, i c represents the column of detection points, j c Represents the row of detection points, m C Indicates the total number of columns of position points in the third scan, n c Indicates the total number of rows of position points in the third scan, m c 、n c The spacing between adjacent detection points is selected between 0.5 and 2 mm, depending on the size of the composite material sample being evaluated and the density of the third scanning detection points.

[0089] Step 302: Calculate the average value of the third scan according to Formula 5

[0090]

[0091] Step 303: Count the position points that meet the third screening condition to obtain the third detection point number N c .

[0092] The third screening condition is: If satisfied, then N c =N c +1,N c The initial value of is 0, and ΔG is the amplitude difference of the third scan C, which is determined by experiments according to the requirements of porosity ultrasonic C scan assessment.

[0093] Step 304: Calculate the uniformity coefficient of the third scan according to the third detection point number

[0094] The third scanning uniformity coefficient is evaluated as follows: When the uniformity of the third scan of the sample meets the requirements, it passes the assessment. is the third uniformity threshold of the sample.

[0095] The uniformity coefficient of the sample porosity is calculated as follows:

[0096] Step 401: Obtaining sample porosity detection data.

[0097] Formula 7 shows the matrix D of the porosity values ​​at each detection position of the sample:

[0098]

[0099] Among them, i d Represents the column of detected location points, j d Indicates the row of detected position points, m d Indicates the total number of columns, n d is the total number of rows; m d 、n d The spacing between adjacent detection points is between 2mm and 10mm, which is determined by the size of the sample and the density of the locations.

[0100] Step 402: Calculate the average value of the porosity. The calculation method is shown in Formula 8.

[0101]

[0102] Step 403: Count the position points that meet the fourth screening condition to obtain the fourth detection point number N d .

[0103] when Then N d =N d +1,N dThe initial value of is 0, and ΔD is the difference in ultrasonic porosity numerical evaluation value, which is determined by experiments according to the requirements of ultrasonic numerical evaluation of porosity.

[0104] Step 404: Calculate the porosity uniformity coefficient according to the fourth detection point number

[0105] The porosity uniformity coefficient is evaluated as follows: When the ultrasonic porosity uniformity of the sample meets the requirements, the uniformity is evaluated by numerically evaluating the ultrasonic porosity of the composite material comparison test block. The fourth uniformity threshold for numerical evaluation of ultrasonic porosity for a given composite porosity comparison test piece.

[0106] After the above evaluation, the samples are judged to meet the uniformity requirements, and the evaluation results are recorded and archived.

[0107] The uniformity of the sample can be evaluated by the uniformity coefficient of some items according to the test environment. In a specific test, each uniformity coefficient is required to be greater than or equal to the corresponding threshold value. The porosity uniformity evaluation method of the present invention can meet the evaluation of different detection scenarios and different types of composite porosity comparison test blocks. The evaluation efficiency is higher and the cost is lower. The evaluation results are more representative and accurate. It is more conducive to establishing the rationality, correctness and accuracy of the ultrasonic porosity evaluation method of composite parts, avoiding the misjudgment and missed detection of the ultrasonic porosity detection of composite parts caused by the incorrectness and discreteness of the composite porosity comparison test blocks, and is more conducive to the precise control of the quality of composite parts and process optimization.

[0108] In a specific embodiment, a certain company's MUT-1 with ultrasonic A-scan and ultrasonic porosity numerical evaluation functions and CUS-21J ultrasonic testing system with ultrasonic C-scan function were used for testing. Composite porosity comparison test blocks with different porosity differences of different layers and thicknesses were selected to complete the uniformity evaluation of a series of composite porosity comparison test blocks.

[0109] Ultrasonic A-scan tests were performed on the porosity comparison test blocks of different composite materials, and the 200×100 detection position point amplitude matrix U was recorded. The spacing between adjacent detection position points was selected as 5mm, 7mm, and 10mm respectively. The average value of U Respectively: 20dB, 26dB, 31dB, composite porosity comparison test block porosity ultrasonic A scan uniformity coefficient They are: 88%, 90%, 92%, given When the porosity of the composite material is 80%, the ultrasonic A-scan uniformity of the comparison test block meets the requirements. Requirements, passed the uniformity assessment of the first scan.

[0110] The composite porosity comparison test block was tested by ultrasonic C scanning, and the matrix G of ultrasonic C scanning values ​​of 300×200 test points was recorded. The spacing between adjacent test points was selected as 0.5mm, 1mm, and 2mm, respectively. The average value of G The porosity of the composite material is compared with that of the test block. The ultrasonic C-scan uniformity coefficient is 25dB, 31dB and 36dB respectively. They are: 89%, 91%, 93%, respectively. When the porosity of the composite material is 85%, the ultrasonic A-scan uniformity of the comparison test block meets the requirements. Requirements, passed the uniformity assessment of the third scan.

[0111] Ultrasonic numerical evaluation was performed on the porosity comparison test blocks of different composite materials. The matrix D of the ultrasonic porosity values ​​of 100×100 detection points was recorded. The spacing between adjacent detection points was selected as 2mm, 5mm, and 10mm respectively. The uniformity coefficient of ultrasonic porosity numerical evaluation of the composite material porosity comparison test block was calculated. They are 88%, 91% and 92% respectively. When the porosity of the composite material is 80%, the uniformity of the ultrasonic porosity numerical evaluation of the comparison test block meets the requirements. Requirements, passed the porosity uniformity assessment.

[0112] The results show that good practical detection effects have been achieved, which can significantly improve the preparation efficiency of composite porosity comparison test blocks, significantly improve the quality of composite porosity comparison test blocks, and greatly improve the accuracy and correctness of ultrasonic porosity evaluation of composite parts based on composite porosity comparison test blocks.

[0113] The present invention also provides a detection device for implementing the above method, such as Figure 3 As shown, it includes a transducer 1, a first scanning unit 2, a third scanning unit 3, a porosity detection unit 4 and an evaluation module 5.

[0114] The transducer 1 is used to perform ultrasonic testing on the sample to obtain ultrasonic data;

[0115] The first scanning unit 2 is used to obtain a first scan A according to the ultrasound data;

[0116] The third scanning unit 3 is used to obtain a third scan C according to the ultrasound data;

[0117] The porosity detection unit 4 is used to obtain the porosity of the sample according to the ultrasonic data;

[0118] The evaluation module 5 is used to calculate the evaluation index according to the detection data; and to evaluate the uniformity of the sample according to the evaluation index and the corresponding threshold value.

[0119] The evaluation module 5 can also be used to save data and generate test reports.

[0120] In view of the lack of porosity uniformity characterization model and non-destructive porosity quantitative evaluation method in the prior art, the present invention designs a specific porosity uniformity characterization model and quantification method for samples based on acoustic fusion, which can quantitatively evaluate the actual distribution uniformity of pores in composite material porosity comparison test blocks, is conducive to forming an effective composite material porosity comparison test block, avoids misjudgment and missed detection of composite material part porosity ultrasonic detection, and improves the correctness and effectiveness of composite material part porosity ultrasonic detection results; in the composite material porosity comparison test block uniformity evaluation method, an interconnected constraint mechanism and a characterization model and algorithm of multi-acoustic method fusion are introduced, which solves the mutual mapping and quantitative verification between different composite material porosity comparison test block evaluation methods, can better characterize the uniformity of composite material porosity comparison test blocks, and then be used to form an effective composite material porosity comparison test block, which is not easy to cause misjudgment and missed detection of composite material part porosity ultrasonic detection, and significantly improves the correctness and effectiveness of the impact of composite material part porosity ultrasonic detection results.

[0121] It should be noted that the uniformity evaluation of the present invention can be used to evaluate both comparative test blocks and samples such as composite material products.

[0122] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for evaluating porosity uniformity, characterized in that: The following steps are involved: Collect any of the following ultrasonic test data for the sample: a first scan based on an ultrasonic reflection contact method, a third scan based on an ultrasonic penetration method, and a sample porosity; Calculate any one of the following evaluation indicators or a combination thereof through the ultrasonic detection data: uniformity coefficient of the first scan, the third scan and the sample porosity; The uniformity of the sample is evaluated by the evaluation index and the corresponding threshold.

2. The evaluation method according to claim 1, characterized in that: If the evaluation indicator is greater than or equal to the corresponding threshold, the sample passes the uniformity evaluation of the evaluation indicator.

3. The evaluation method according to claim 2, characterized in that: All evaluation indicators are greater than or equal to the corresponding thresholds, and the sample passes the uniformity evaluation.

4. The evaluation method according to claim 1, characterized in that: The evaluation index includes a uniformity coefficient, and a method for calculating the uniformity coefficient includes: Calculating an average value based on the ultrasonic detection data; Calculate the screening conditions according to the average value and the difference; Calculating the number of detection points that meet the screening conditions; The uniformity coefficient is calculated according to the proportion of the detection points.

5. The evaluation method according to claim 4, characterized in that: The method of calculating the uniformity coefficient of the first scan includes: Get the data of the first scan, the matrix of the first scan is expressed as: Among them, U represents the matrix of the first scan, Represented as the i-th u Column, No. j u The amplitude of the detection position point of the line, m u Indicates the total number of columns of position points in the first scan, n u Indicates the total number of rows of position points in the first scan; Calculate the average value of the first scan, in, Expressed as the average of the first scan; The position points satisfying the first screening condition are counted to obtain a first number of detection points, wherein the first screening condition is expressed as: ΔU is the level difference of the first scanning amplitude; According to the first detection point number, calculate the uniformity coefficient of the first scan: in, Expressed as the uniformity coefficient of the first scan.

6. The evaluation method according to claim 4, characterized in that: The uniformity coefficient calculation method of the third scan C includes: Get the data for the third scan: Among them, G represents the matrix of the third scan, Represented as the i-th c Column, No. j c The amplitude of the line detection position point, m C Indicates the total number of columns of position points in the third scan, n c Indicates the total number of rows of position points in the third scan; Compute the average of the third scan: in, Expressed as the average of the third scan; The position points satisfying the third screening condition are counted to obtain a third number of detection points, wherein the third screening condition is expressed as: ΔG is the level difference of the third scanning amplitude; According to the third detection point number, calculate the uniformity coefficient of the third scan: in, Expressed as the uniformity coefficient of the third scan.

7. The evaluation method according to claim 4, characterized in that: Methods for calculating the uniformity coefficient of sample porosity include: Get the matrix of sample porosity: Where D represents the matrix of sample porosity, Represented as the i-th d Column, No. j d The porosity value of the row, m d Indicates the total number of columns, n d is the total number of rows; Calculate the average porosity: in, It is expressed as the average value of porosity; The position points satisfying the fourth screening condition are counted to obtain a fourth number of detection points, wherein the fourth screening condition is expressed as: ΔD is the difference in porosity values; According to the fourth detection point number, calculate the uniformity coefficient of porosity: in, Expressed as the uniformity coefficient of porosity.

8. The evaluation method according to claim 1, characterized in that: The sample is a composite material comparison test block or a composite material product.

9. A detection device, characterized in that: Used to implement the evaluation method according to any one of claims 1 to 8, the detection device comprises a transducer, a first scanning unit, a third scanning unit, a porosity detection unit and an evaluation module; The transducer is used to perform ultrasonic testing on the sample to obtain ultrasonic data; The first scanning unit is used to obtain a first scan based on the ultrasound data; The third scanning unit is used to obtain a third scan according to the ultrasound data; The porosity detection unit is used to obtain the porosity of the sample according to the ultrasonic data; The evaluation module is used to calculate the evaluation index according to the detection data; and to evaluate the uniformity of the sample according to the evaluation index and the corresponding threshold value.

10. The detection device according to claim 9, characterized in that: The evaluation module is also used to save data and generate a test report.

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