Method for detecting mixing uniformity of energetic material

Abstract

The invention discloses a method for detecting the mixing uniformity of an energetic material, and belongs to the technical field of material uniformity inspection, and the method comprises the following steps: S1, mixing the energetic material and a tracer agent according to different mass ratios to obtain a mixed sample, illuminating and shooting an image; s2, analyzing the image, and selecting a mixed sample in which the tracer concentration and the color index have a linear relationship as a standard sample; s3, taking the standard samples with different concentrations, adding the standard samples into a mixing device for mixing, and carrying out image shooting; and S4, sampling the mixed image of the standard samples, and calculating the variable coefficient of the color index to evaluate the mixing uniformity. According to the method provided by the invention, real-time monitoring and detection analysis of the energetic material mixing process can be realized, the method is simple in sample preparation, convenient to operate and efficient in detection, the mixing uniformity of the energetic material can be evaluated by acquiring the image of the energetic material added with the tracer agent, and the application range of online detection in the field of energetic material detection is widened.

Description

Technical Field

[0001] The invention relates to the field of material uniformity inspection, and in particular to a method for inspecting the mixing uniformity of energetic materials. Background Art

[0002] Energetic materials can store energy and release a large amount of energy under certain conditions. They are mainly used in military, aerospace, coal mining and other fields. Energetic materials are multi-component formula systems. The mixing uniformity between the components is an important indicator affecting the quality stability and application reliability of energetic materials. Therefore, it is necessary to quickly and accurately detect the mixing uniformity of energetic materials.

[0003] At present, the detection of mixing uniformity mainly uses electron tomography, energy dispersive X-ray spectrometer and scanning electron microscope for offline detection, but the offline detection method has problems such as low detection efficiency, large human operation error, small sample interval and low representativeness. Therefore, an online detection method can be adopted, which can monitor in real time and provide timely feedback to the operator, with high work efficiency. However, the current online detection methods relying on temperature, conductivity and optical images have high requirements for tracers. If fluorescent materials are used as tracers, they will face the shortcomings of poor stability, poor water resistance, poor high temperature resistance and poor compatibility with the materials to be detected. This will cause the fluorescent materials to be used for the detection of energetic slurry mixing uniformity. The luminescence performance is significantly reduced and the detection signal cannot be collected. Therefore, it is very necessary to establish an online detection method suitable for detecting the mixing uniformity of energetic materials to realize real-time monitoring and detection analysis of the energetic material mixing process, reduce the negative impact of tracers, environment and equipment in monitoring, and improve the accuracy of online detection results. Summary of the invention

[0004] The present invention aims to overcome the problem that the online detection method in the prior art has high requirements on tracers, environment and equipment, and provides a method for detecting the mixing uniformity of energetic materials.

[0005] To achieve the above object, the technical solution of the present invention is: to provide a method for detecting the mixing uniformity of energetic materials, comprising:

[0006] Step S1: mixing energetic materials and tracers at different mass ratios to obtain mixed samples, irradiating the mixed samples to make the tracers develop color, and then taking images to obtain mixed sample images;

[0007] Step S2: Analyze the mixed sample image and obtain a color index, analyze the change of the color index mean with the tracer mass ratio, and select a mixed sample in which the tracer concentration and the color index have a linear relationship as a standard sample;

[0008] Step S3: adding the standard samples of different concentrations into a mixing device for mixing, and taking images to obtain images of the mixed standard samples;

[0009] Step S4: sampling the image of the standard sample after mixing and obtaining a color index, calculating the coefficient of variation of the color index, and evaluating the mixing uniformity with the coefficient of variation.

[0010] In one embodiment, the tracer in step S1 is selected from rhodamine 6b, modified strontium aluminate, and fluorescein isothiocyanate, and the modifier is selected from silicon dioxide, PMMA, and aluminum oxide.

[0011] In one embodiment, the mass percentage of the tracer in step S1 is 1-15%.

[0012] In one embodiment, the energetic material in step S1 is selected from octogen and photosensitive resin, octogen, aluminum powder and photosensitive resin, RDX, aluminum powder and TNT, Cl-20, aluminum powder and photosensitive resin.

[0013] In one embodiment, the illumination in step S1 is selected from fluorescent lamp, ultraviolet lamp, infrared lamp, and the operating parameters of the ultraviolet lamp are 365nm, 3W.

[0014] In one embodiment, in step S2 and step S4, Matlab image processing program is used for analysis.

[0015] In one embodiment, in step S2, the mass percentage of the tracer in the standard sample is 1% and 5%.

[0016] In one embodiment, in step S2, RGB, HSV, YCbCr, and CIE color gamuts are selected, and the color index under the RGB color gamut is selected from grayscale value, lightness, and brightness.

[0017] In one embodiment, in step S3, the mixing device is selected from a static mixer, a vertical kneader, and a horizontal kneader.

[0018] In one embodiment, in step S4, the average value of the color index is first calculated, and the average value is:

[0019]

[0020] The standard deviation is further calculated, and the standard deviation of the color index is:

[0021]

[0022] In the formula, C n is the color index of the nth pixel, is the total average value of the color index of the pixel points in the sampling area, and k is the number of sampling points;

[0023] The coefficient of variation of the color index can be obtained from this, and the formula is as follows:

[0024]

[0025] In the formula, CoV is the coefficient of variation, σ is the standard deviation of the index of different pixel points, is the average value of different pixel indexes.

[0026] In summary, the present invention provides a method for detecting the mixing uniformity of energetic materials, which can realize real-time monitoring and detection analysis of the energetic material mixing process. The method has simple sample preparation, convenient operation, and efficient detection. The mixing uniformity of energetic materials can be evaluated by obtaining images of energetic materials with tracers added, thereby broadening the application of online detection in the field of energetic material detection. At the same time, the use of modified fluorescent agents as tracers can not only ensure that the tracers are not easily decomposed after being dissolved in the resin, but also increase the existence time of the fluorescent signal, which is beneficial to detection and analysis. In addition, the detection method also reduces the negative impact of tracers, environment, and equipment on the detection of energetic material uniformity during the online monitoring process, and improves the accuracy of online detection results.

[0027] In order to make the above features and advantages of the invention more obvious and easy to understand, embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a flow chart of the present invention.

[0029] Figure 2 These are images of mixed samples at different tracer concentrations in the present invention.

[0030] Figure 3 for Figure 2 Relationship between the mean brightness of the mixed sample and the mass percentage of the tracer.

[0031] Figure 4 1 is an image and brightness distribution diagram of the mixed sample before and after passing through the static mixer in Example 1 of the present invention.

[0032] Figure 5 1 is an image and a brightness distribution diagram of the mixed sample before and after passing through the vertical kneading machine in Example 2 of the present invention.

[0033] Figure 6 It is the image and brightness distribution diagram of the mixed sample after passing through the horizontal kneading machine in Example 3 of the present invention. DETAILED DESCRIPTION

[0034] In order to make the purpose and technical solution of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] The present invention provides a method for detecting the uniformity of energetic material mixing. Figure 1 As shown, the specific steps include:

[0036] Step S1: mixing energetic materials and tracers at different mass ratios to obtain mixed samples, irradiating the mixed samples to make the tracers develop color, and then taking images to obtain mixed sample images;

[0037] Step S2: Analyze the mixed sample image and obtain a color index, analyze the change of the color index mean with the tracer mass ratio, and select a mixed sample in which the tracer concentration and the color index have a linear relationship as a standard sample;

[0038] Step S3: adding the standard samples of different concentrations into a mixing device for mixing, and taking images to obtain images of the mixed standard samples;

[0039] Step S4: sampling the image of the standard sample after mixing and obtaining a color index, calculating the coefficient of variation of the color index, and evaluating the mixing uniformity with the coefficient of variation.

[0040] In the above step S1, the energetic material may be selected from octogen and photosensitive resin, or octogen, aluminum powder and photosensitive resin, RDX, aluminum powder and TNT, Cl-20, aluminum powder and photosensitive resin, preferably octogen and photosensitive resin. The mass percentage of the tracer is 1-15%. The tracer is selected from a combination of one or more of rhodamine 6b, modified strontium aluminate, and fluorescein isothiocyanate, preferably modified strontium aluminate. The modified material is selected from silicon dioxide, PMMA, aluminum oxide, etc., preferably silicon dioxide. The illumination may be provided by a fluorescent lamp, an ultraviolet lamp, or an infrared lamp, preferably an ultraviolet lamp, and irradiated under the conditions of 365nm and 3W. The use of a low-power ultraviolet lamp can reduce the energy stimulation received by the energetic material and prevent decomposition and energy release. The captured image may be a color image or a grayscale image, preferably a color image.

[0041] In the above step S2, the image is processed using Matlab software, and RGB, HSV, YCbCr, CIE color gamuts can be selected, preferably RGB color gamut. The color index under the RGB color gamut is selected from gray value, lightness, and brightness, and the color index under the CIE color gamut can be selected from L*a*b, preferably lightness under the RGB color gamut.

[0042] In the above step S3, the standard sample is selected from a mixed sample whose color index mean value changes linearly with the mass percentage of the tracer, and the mass percentage of strontium aluminate in the standard sample is preferably 1% and 5%. The mixing device is selected from a static mixer, a vertical kneader, and a horizontal kneader. The image taken is a color image.

[0043] In the above step S4, Matlab software is used to sample the image, and all pixels or multiple regions can be selected during sampling, preferably all pixels are selected. A color segmenter, a custom function or an image batch processor can be used to convert the color information at the sampling location into a color index, preferably a custom function.

[0044] In addition, when the above steps S2 and S4 use Matlab software to analyze the image, if the tracers in different mixed samples show different colors, the L*a*b value of the image sampling area can be obtained under the CIE color gamut, and the uniformity of the mixture can be analyzed by the change trend of the color function in the L*a*b coordinate system; the grayscale value, lightness, and brightness of the color displayed by a certain mixed sample in the sampling area can also be analyzed separately under the RGB color gamut, and the mixing uniformity can be analyzed by calculating the coefficient of variation.

[0045] If the tracers in different mixed samples show the same color, the grayscale value, lightness, and brightness intervals of the image sampling area can be analyzed in the RGB color gamut, and the different energetic materials can be distinguished by the interval boundary values. The coefficient of variation can be calculated to analyze the mixing uniformity. The color index can also be calibrated in the RGB color gamut, and the mixing uniformity can be analyzed by the linear change of the color index with the tracer concentration.

[0046] Among them, the color index obtained by sampling needs to be averaged, and the average value calculation formula of the color index is:

[0047]

[0048] The standard deviation of the color index is calculated as:

[0049]

[0050] In the formula, C n is the color index of the nth pixel, is the total average color index of the pixels in the sampling area, and k is the number of sampling points.

[0051] The coefficient of variation of the color index is calculated as follows:

[0052]

[0053] In the formula, CoV is the coefficient of variation, σ is the standard deviation of the index of different pixel points, is the average value of different pixel indices.

[0054] In the above technical solution, the silica-modified strontium aluminate used is soluble in the photosensitive resin, has little effect on the rheological properties of the energetic material, and ensures the accuracy of the detection of mixing uniformity; the use of fluorescent agent as a tracer reduces the impact of the experimental environment on the test results, has low requirements for the device, and reduces the detection cost and the difficulty of device assembly. At the same time, after being modified by silica surface coating, strontium aluminate has good stability and is not easy to decompose after being dissolved in the resin, which effectively increases the existence time of the fluorescent signal and is conducive to detection and analysis. In addition, 365nm, 3W ultraviolet light is used for illumination. Under this condition, the fluorescent agent can fully develop color and avoid the photosensitive resin from solidifying and affecting the mixing effect.

[0055] The present invention uses the change of color index as a measure to evaluate the uniformity of energetic material mixing. The standardized calibration experiment is simple to operate, the brightness signal is easy to observe and changes significantly with the concentration, and the collection and analysis are more convenient. In addition, the image is processed using Matlab software to quickly obtain the detection result of energetic material mixing uniformity.

[0056] The present application is further described in detail with reference to specific embodiments.

[0057] Embodiment 1:

[0058] Step S1: Select an energetic material containing octogen and a photosensitive resin for detection, mix the dried octogen and the photosensitive resin in a mass ratio of 7:3, and add 1-15% by mass of silica-modified strontium aluminate as a tracer to finally obtain a mixed sample. Irradiate the mixed samples with different tracer contents with an ultraviolet lamp, and take images after color development.

[0059] Step S2: Use Matlab software to process the image, process and analyze the image in the RGB color domain, and obtain the blue brightness mean of different mixed samples. Figure 2 As shown in Figure 2, as the mass percentage of silica-modified strontium aluminate increases, the blue brightness of the image of the mixed sample continues to deepen. When the mass percentage of silica-modified strontium aluminate is 1-5%, Figure 3As shown, the brightness mean of the mixed sample image changes linearly with the mass percentage of silica-modified strontium aluminate. Therefore, a mixed sample with a mass percentage of 5% silica-modified strontium aluminate and a mixed sample with a mass percentage of 1% silica-modified strontium aluminate were selected as standard samples.

[0060] Step S3: Add both standard samples into the static mixer, and take images of the mixed samples in each static mixing element.

[0061] Step S4: Use the color segmenter of Matlab software to obtain the blue brightness distribution of all pixels in the image, such as Figure 4 As shown in the figure, the initial distribution of the blue light index is mainly around 50 and 170. After adding the static mixer, the distribution of the blue light index changes. When the number of static mixing elements involved in the mixing increases, the distribution of the blue light index begins to move closer to the middle, and after passing through the last static mixing element, the blue light index is mainly distributed around 70 to 80. By comparing the distribution of the blue light index of the samples before and after mixing in the static mixer, it can be preliminarily judged that the mixing uniformity has been improved.

[0062] We further use the custom function in Matlab to sample all the pixels in the image, obtain the blue brightness value, and solve the coefficient of variation of the blue brightness of the samples after being acted on by different numbers of static mixers. The results are as follows:

[0063]

[0064] Since the final coefficient of variation is less than 0.05, the mixing uniformity is good.

[0065] Embodiment 2:

[0066] Step S1: Select an energetic material containing octogen and a photosensitive resin for detection, mix the dried octogen and the photosensitive resin in a mass ratio of 7:3, and add 1-15% by mass of silica-modified strontium aluminate as a tracer to finally obtain a mixed sample. Irradiate the mixed samples with different tracer contents with an ultraviolet lamp, and take images after color development.

[0067] Step S2: Use Matlab software to process the image, process and analyze the image in the RGB color domain, and obtain the blue brightness mean of different mixed samples. Figure 2 As shown in Figure 2, as the mass percentage of silica-modified strontium aluminate increases, the blue brightness of the image of the mixed sample continues to deepen. When the mass percentage of silica-modified strontium aluminate is 1-5%, Figure 3As shown, the brightness mean of the mixed sample image changes linearly with the mass percentage of silica-modified strontium aluminate. Therefore, a mixed sample with a mass percentage of 5% silica-modified strontium aluminate and a mixed sample with a mass percentage of 1% silica-modified strontium aluminate were selected as standard samples.

[0068] Step S3: Add the two standard samples into the feeding bin of the vertical kneader and mix them, and take images of the samples in the vertical kneader every 2 minutes.

[0069] Step S4: Use the color segmenter of Matlab software to obtain the blue brightness distribution of all pixels in the image, such as Figure 5 As shown, the initial distribution of the blue light index is mainly around 50 and 170. After adding the vertical kneading machine, the distribution of the blue light index begins to move toward the middle, indicating that the mixing effect is continuously improved.

[0070] We further use the custom function in Matlab to sample all the pixels in the image, obtain the blue brightness value, and solve the coefficient of variation of the blue brightness of the samples at different mixing times. The results are as follows:

[0071]

[0072] Since the final coefficient of variation was greater than 0.05, it indicated that the mixing uniformity was poor.

[0073] Embodiment 3:

[0074] Step S1: Select an energetic material containing octogen and a photosensitive resin for detection, mix the dried octogen and the photosensitive resin in a mass ratio of 7:3, and add 1-15% by mass of silica-modified strontium aluminate as a tracer to finally obtain a mixed sample. Irradiate the mixed samples with different contents of silica-modified strontium aluminate with an ultraviolet lamp, and take images after color development.

[0075] Step S2: Use Matlab software to process the image, process and analyze the image in the RGB color domain, and obtain the blue brightness mean of different mixed samples. Figure 2 As shown in Figure 2, as the mass percentage of silica-modified strontium aluminate increases, the blue brightness of the image of the mixed sample continues to deepen. When the mass percentage of silica-modified strontium aluminate is 1-5%, Figure 3 As shown, the brightness mean of the mixed sample image changes linearly with the mass percentage of silica-modified strontium aluminate. Therefore, a mixed sample with a mass percentage of 5% silica-modified strontium aluminate and a mixed sample with a mass percentage of 1% silica-modified strontium aluminate were selected as standard samples.

[0076] Step S3: Add the two standard samples into the horizontal kneading machine and mix for 5 minutes, and sample and photograph the mixed samples in multiple areas in the horizontal kneading bin.

[0077] Step S4: Use the color segmenter of Matlab software to obtain the blue brightness distribution of all pixels in the image, such as Figure 6 As shown, the blue light index distribution of the standard sample after mixing in the vertical kneader is mainly around 75, indicating that the mixing effect is good.

[0078] A custom function in Matlab was further used to sample all pixels in the image to obtain the blue brightness value, and the coefficient of variation of the blue brightness of samples in different areas in the horizontal kneading machine was solved. The obtained coefficients of variation were 0.0094, 0.0103, 0.0086 and 0.0079, respectively.

[0079] Since the coefficient of variation is less than 0.05, it indicates that the mixing uniformity is good.

[0080] In summary, the present invention provides a method for detecting the mixing uniformity of energetic materials, which can realize real-time monitoring and detection analysis of the energetic material mixing process. The method has simple sample preparation, convenient operation, and efficient detection. The mixing uniformity of energetic materials can be evaluated by obtaining images of energetic materials with tracers added, thereby broadening the application of online detection in the field of energetic material detection. At the same time, the use of modified fluorescent agents as tracers can not only ensure that the tracers are not easily decomposed after being dissolved in the resin, but also increase the existence time of the fluorescent signal, which is beneficial to detection and analysis. In addition, the detection method also reduces the negative impact of tracers, environment, and equipment on the detection of energetic material uniformity during the online monitoring process, and improves the accuracy of online detection results.

[0081] Although the present invention has been disclosed as above by way of embodiments, it is not intended to limit the present invention. Any person having ordinary knowledge in the technical field may make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the scope of the attached patent application.

Claims

1. A method for detecting the uniformity of energetic material mixing, characterized in that: include, Step S1: mixing energetic materials and tracers at different mass ratios to obtain mixed samples, irradiating the mixed samples to make the tracers develop color, and then taking images to obtain mixed sample images; Step S2: Analyze the mixed sample image and obtain a color index, analyze the change of the color index mean with the tracer mass ratio, and select a mixed sample in which the tracer concentration and the color index have a linear relationship as a standard sample; Step S3: adding the standard samples of different concentrations into a mixing device for mixing, and taking images to obtain images of the mixed standard samples; Step S4: sampling the image of the standard sample after mixing and obtaining a color index, calculating the coefficient of variation of the color index, and evaluating the mixing uniformity with the coefficient of variation.

2. A method for detecting the uniformity of energetic material mixing according to claim 1, characterized in that: The tracer in step S1 is selected from rhodamine 6b, modified strontium aluminate, and fluorescein isothiocyanate, and the modifier is selected from silicon dioxide, PMMA, and aluminum oxide.

3. A method for detecting the uniformity of energetic material mixing according to claim 2, characterized in that: The mass percentage of the tracer in step S1 is 1-15%.

4. A method for detecting the uniformity of energetic material mixing as claimed in claim 3, characterized in that: The energetic material in step S1 is selected from octogen and photosensitive resin, octogen, aluminum powder and photosensitive resin, RDX, aluminum powder and TNT, Cl-20, aluminum powder and photosensitive resin.

5. A method for detecting the uniformity of energetic material mixing as claimed in claim 4, characterized in that: The illumination in step S1 is selected from fluorescent lamp, ultraviolet lamp and infrared lamp, and the working parameters of the ultraviolet lamp are 365nm and 3W.

6. A method for detecting uniformity of energetic material mixing according to claim 1, characterized in that: In the step S2 and the step S4, the image processing program of Matlab is used for analysis.

7. A method for detecting the uniformity of energetic material mixing according to claim 1, characterized in that: In the step S2, the mass percentage of the tracer in the standard sample is 1% and 5%.

8. A method for detecting the mixing uniformity of energetic materials according to claim 7, characterized in that: In the step S2, RGB, HSV, YCbCr, and CIE color gamuts are selected, and the color index under the RGB color gamut is selected from grayscale value, lightness, and brightness.

9. A method for detecting the uniformity of energetic material mixing according to claim 1, characterized in that: In the step S3, the mixing device is selected from a static mixer, a vertical kneader, and a horizontal kneader.

10. A method for detecting uniformity of energetic material mixing according to claim 1, characterized in that: In step S4, the average value of the color index is first calculated, and the average value is: The standard deviation is further calculated, and the standard deviation of the color index is: In the formula, C n is the color index of the nth pixel, is the total average value of the color index of the pixel points in the sampling area, and k is the number of sampling points; The coefficient of variation of the color index can be obtained from this, and the formula is as follows: In the formula, CoV is the coefficient of variation, σ is the standard deviation of the index of different pixel points, is the average value of different pixel indices.

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