Metal tensile test system and metal tensile sample detection method and device

Abstract

The invention relates to the technical field of metal tensile detection, and discloses a metal tensile test system and a metal tensile sample detection method and device.According to the metal tensile test system, a metal tensile sample is clamped and centered, it is guaranteed that the metal tensile sample meets the clamping requirement of a tensile test, and it is guaranteed that the test is conducted smoothly; secondly, through two cameras which are orthogonally arranged, the acquisition of gauge length stretching section images of the metal stretching sample before the stretching test and after the fracture is realized, and the initial cross section size, the initial edge line, the fracture cross section size and the broken edge line are determined based on the gauge length stretching section images of the metal stretching sample before the stretching test and after the fracture; the metal tensile property index is determined according to the initial cross section size, the initial edge line, the fracture cross section size and the fractured edge line, so that the automatic measurement of the metal tensile property index is realized, the measurement error or deviation caused by manual operation is effectively avoided, and the metal tensile test efficiency and precision are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of metal tensile testing, and in particular to a metal tensile testing system, a metal tensile specimen testing method and a device. Background Art

[0002] The tensile test of metal materials refers to a test that obtains the mechanical properties of materials by breaking the specimen by subjecting both ends of the specimen to axial tensile forces in opposite directions. The mechanical properties of materials (yield strength, tensile strength, elongation after fracture and reduction of area) obtained by this test method can provide effective data support for the application of metal materials in engineering fields such as aerospace, marine ships, and military industry.

[0003] During the metal tensile specimen testing process, the metal tensile specimen clamping alignment test and the tensile performance index test of the metal material must be judged based on the tester's experience, which is easy to cause measurement deviation and reduce the detection accuracy and efficiency of the metal tensile specimen. Summary of the invention

[0004] In view of this, the present invention provides a metal tensile testing system, a metal tensile specimen detection method and a device to solve the problem that the metal tensile specimen detection process is prone to measurement deviation, thereby reducing the detection accuracy and efficiency of the metal tensile specimen.

[0005] In a first aspect, the present invention provides a metal tensile testing system, comprising: a universal testing machine, a first camera, a second camera, a metal tensile sample and a data acquisition and processing device, wherein the universal testing machine comprises an upper fixture, a lower fixture and an extensometer; the first camera is located on the left or right side of the metal tensile sample, the second camera is located directly in front of the metal tensile sample, the first camera and the second camera are arranged orthogonally, the upper fixture and the lower fixture respectively fix and clamp the upper end and the lower end of the metal tensile sample, the extensometer is located in the gauge length stretching section of the metal tensile sample, and the data acquisition and processing device is respectively connected to the extensometer, the universal testing machine, the first camera and the second camera;

[0006] a data acquisition and processing device, used for acquiring the gauge length stretching section image of the metal tensile sample before the tensile test sent by the first camera and the second camera, determining the initial cross-sectional size of the metal tensile sample and the initial edge line of the gauge length stretching section based on the gauge length stretching section image of the metal tensile sample before the tensile test, and performing clamping and centering processing on the metal tensile sample;

[0007] An extensometer, used to collect the deformation of the metal tensile sample during the tensile test of the metal tensile sample, until the deformation of the metal tensile sample meets the deformation threshold;

[0008] The data acquisition and processing device is also used to obtain the gauge length stretching section image of the metal tensile sample after the tensile fracture, determine the fracture cross-sectional size of the metal tensile sample and the fractured edge line of the gauge length stretching section based on the gauge length stretching section image of the metal tensile sample after the tensile fracture, and determine the metal tensile performance index based on the initial cross-sectional size, initial edge line, fracture cross-sectional size and fractured edge line; wherein, the gauge length stretching section image of the metal tensile sample after the tensile fracture is an image captured by the first camera and the second camera when the deformation of the metal tensile sample meets the deformation threshold.

[0009] A metal tensile testing system provided in this embodiment ensures that the metal tensile sample meets the clamping requirements of the tensile test and ensures the smooth progress of the experiment by clamping and centering the metal tensile sample. Secondly, through two orthogonally arranged cameras, the collection of the gauge length tensile section images of the metal tensile sample before the tensile test and after fracture is realized, and the initial cross-sectional size, initial edge line, fracture cross-sectional size and post-fracture edge line are determined based on the gauge length tensile section images of the metal tensile sample before the tensile test and after fracture, and then the metal tensile performance index is determined through the initial cross-sectional size, initial edge line, fracture cross-sectional size and post-fracture edge line, thereby realizing the automatic measurement of the metal tensile performance index, effectively avoiding measurement errors or deviations caused by manual operation, ensuring the consistency of the metal tensile test results, improving the detection efficiency and accuracy, and being suitable for large-scale sample detection.

[0010] In a second aspect, the present invention provides a metal tensile specimen detection method, which is applied to a data acquisition and processing device in the above-mentioned metal tensile test system; the method comprises:

[0011] Acquire a gauge length stretching section image of the metal tensile sample before the tensile test, and determine an initial cross-sectional size of the metal tensile sample and an initial edge line of the gauge length stretching section based on the gauge length stretching section image of the metal tensile sample before the tensile test;

[0012] The metal tensile sample is clamped and centered based on the initial edge line of the gauge length tensile section;

[0013] Acquire an image of a gauge length stretching section after the metal tensile sample is stretched and fractured, and determine the fracture cross-sectional size of the metal tensile sample and the edge line after the fracture of the gauge length stretching section based on the image of the gauge length stretching section after the metal tensile sample is stretched and fractured;

[0014] The metal tensile performance index is determined based on the initial section size, the initial edge line, the fracture section size and the edge line after fracture; the metal tensile performance index includes the elongation after fracture and the section shrinkage rate.

[0015] A metal tensile specimen detection method provided in the present embodiment avoids the defect that the metal tensile test cannot realize the clamping and centering detection of the metal tensile specimen by clamping and centering the metal tensile specimen, ensures that the metal tensile specimen meets the clamping requirements of the tensile test, and ensures the smooth progress of the experiment; secondly, based on the gauge length tensile segment image of the metal tensile specimen before the tensile test and after fracture, the initial cross-sectional size, initial edge line, fracture cross-sectional size and post-fracture edge line are determined, and then the metal tensile performance index is determined through the initial cross-sectional size, initial edge line, fracture cross-sectional size and post-fracture edge line, thereby realizing the automatic measurement of the metal tensile performance index, effectively avoiding the measurement error or deviation caused by manual operation, ensuring the consistency of the metal tensile test results, and improving the detection efficiency and accuracy.

[0016] In an optional embodiment, determining the initial cross-sectional size of the metal tensile sample and the initial edge line of the gauge length tensile section based on the gauge length tensile section image of the metal tensile sample before the tensile test includes:

[0017] Performing image processing on the gauge length stretching segment image of the metal tensile sample before the tensile test to obtain an initial target image;

[0018] Perform edge detection on the initial target image to determine the initial edge line of the gauge length stretching section;

[0019] The initial cross-sectional dimensions of the metal tensile specimen are determined based on the midpoint of the initial edge line.

[0020] The present embodiment provides a method for detecting a metal tensile specimen, which performs image processing on an image of a gauge length stretching section of the metal tensile specimen before a tensile test, thereby improving the detection accuracy of edge detection. Furthermore, by performing edge detection on the initial target image, automatic tracking and real-time updating of the initial edge line of the gauge length stretching section are achieved, thereby ensuring accurate monitoring of sample deformation during the metal tensile test, avoiding manual adjustment of edge detection parameters, greatly reducing errors caused by human operations, and improving detection efficiency and accuracy.

[0021] In an optional embodiment, the metal tensile sample is clamped and centered based on the initial edge line of the gauge length tensile section, comprising:

[0022] Obtaining an upper gauge length and a lower gauge length of the metal tensile sample, and determining a vertical line based on a midpoint of the upper gauge length and a midpoint of the lower gauge length;

[0023] Calculate the angle between the initial edge line of the gauge stretch section and the vertical line;

[0024] The included angle is compared with the preset angle. If the included angle does not match the preset angle, the metal tensile sample is clamped and aligned and corrected until the included angle matches the preset angle.

[0025] The present embodiment provides a method for detecting a metal tensile specimen. The method calculates the angle between the initial edge line of the gauge length tensile segment and the vertical line, compares the angle with a preset angle, and detects the clamping and centering condition of the current metal tensile specimen based on the comparison result. The method also performs clamping and centering correction on the metal tensile specimen, thereby avoiding the defect that the metal tensile test cannot realize the clamping and centering detection of the metal tensile specimen. The method ensures that the metal tensile specimen meets the clamping requirements of the tensile test, thereby ensuring the smooth progress of the experiment.

[0026] In an optional embodiment, determining the fracture cross-sectional size of the metal tensile sample and the post-fracture edge line of the gauge length tensile section based on the gauge length tensile section image after the metal tensile sample is tensile fractured comprises:

[0027] Determine the post-fracture edge line and fracture morphology line of the gauge length stretching section based on the gauge length stretching section image after the metal tensile sample is stretched and fractured;

[0028] The fracture cross-sectional size is determined based on the distance between the intersection of the fracture edge line and the fracture morphology line.

[0029] A metal tensile specimen detection method provided in this embodiment determines the fracture cross-sectional size by the distance between the intersection of the edge line after fracture and the fracture morphology line, thereby realizing accurate measurement of the fracture size of the metal tensile specimen after the metal tensile test without the need for human intervention, thus avoiding errors caused by manual measurement and improving detection accuracy and efficiency.

[0030] In an optional embodiment, determining the metal tensile performance index based on the initial cross-sectional size, the initial edge line, the fracture cross-sectional size and the fractured edge line includes:

[0031] determining an initial gauge length average of the metal tensile sample based on edge line lengths corresponding to the initial edge lines;

[0032] Determine the average post-fracture gauge length of the metal tensile sample based on the edge line length corresponding to the post-fracture edge line;

[0033] Calculate the elongation after break based on the average value of the initial gauge length and the average value of the gauge length after break;

[0034] The reduction of section is calculated based on the initial section dimensions and the fracture section dimensions.

[0035] A metal tensile specimen testing method provided in this embodiment calculates the elongation after fracture through the average value of the initial gauge length and the average value of the gauge length after fracture, and calculates the cross-sectional shrinkage rate through the initial cross-sectional size and the cross-sectional size after fracture, thereby realizing the cross-sectional size measurement of the metal tensile sample, and an integrated automated test of the elongation after fracture and the cross-sectional shrinkage rate measurement, without the need for human intervention, thus avoiding errors caused by manual measurement, and improving the detection accuracy and efficiency.

[0036] In a third aspect, the present invention provides a metal tensile specimen detection device, the device comprising:

[0037] An acquisition module is used to acquire an image of a gauge length stretching section of a metal tensile sample before a tensile test, and determine an initial cross-sectional size of the metal tensile sample and an initial edge line of the gauge length stretching section based on the image of the gauge length stretching section of the metal tensile sample before the tensile test;

[0038] A processing module, used for clamping and centering the metal tensile sample based on the initial edge line of the gauge length tensile section;

[0039] A first determination module is used to obtain an image of a gauge length stretching section after the metal tensile sample is stretched and fractured, and determine a fracture cross-sectional size of the metal tensile sample and a post-fracture edge line of the gauge length stretching section based on the image of the gauge length stretching section after the metal tensile sample is stretched and fractured;

[0040] The second determination module is used to determine the metal tensile performance index based on the initial cross-sectional size, the initial edge line, the fracture cross-sectional size and the post-fracture edge line; the metal tensile performance index includes the post-fracture elongation and the cross-sectional shrinkage.

[0041] In a fourth aspect, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the metal tensile specimen detection method of the second aspect or any corresponding embodiment thereof by executing the computer instructions.

[0042] In a fifth aspect, the present invention provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to enable a computer to execute the metal tensile specimen testing method of the second aspect or any corresponding embodiment thereof.

[0043] In a sixth aspect, the present invention provides a computer program product, comprising computer instructions, wherein the computer instructions are used to enable a computer to execute the metal tensile specimen detection method of the second aspect or any corresponding embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 is a front view of a metal tensile testing system according to an embodiment of the present invention;

[0046] Figure 2 is a top view of a metal tensile testing system according to an embodiment of the present invention;

[0047] Figure 3 is a schematic flow chart of a metal tensile specimen testing method according to an embodiment of the present invention;

[0048] Figure 4 is a schematic flow chart of another metal tensile specimen testing method according to an embodiment of the present invention;

[0049] FIG5( a ) is an image of a gauge length stretching section of a metal tensile sample before a tensile test captured by a first camera according to an embodiment of the present invention;

[0050] FIG5( b ) is an image of a gauge length stretching section of a metal tensile sample before a tensile test captured by a second camera according to an embodiment of the present invention;

[0051] Figure 6 is a schematic flow chart of another metal tensile specimen testing method according to an embodiment of the present invention;

[0052] FIG. 7( a ) is an image of a gauge length stretching section of a metal tensile sample after tensile fracture captured by a first camera according to an embodiment of the present invention;

[0053] FIG7( b ) is an image of a gauge length stretching section of a metal tensile sample after tensile fracture captured by a second camera according to an embodiment of the present invention;

[0054] Figure 8 is a structural block diagram of a metal tensile specimen detection device according to an embodiment of the present invention;

[0055] Fig. 9 It is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0056] 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 those skilled in the art without creative work are within the scope of protection of the present invention.

[0057] The clamping and centering of metal tensile samples have a great influence on the experimental results. At present, the effect of sample clamping is often judged by visual inspection and the experience of testers, which is prone to deviation. At the same time, in order to calculate the tensile performance indicators of metal materials, the original size of the sample and the distance between the gauges need to be measured before the tensile test. After the tensile test, the broken ends need to be manually spliced ​​to measure the minimum cross-sectional size and the distance between the gauges after breaking. The measurement of these dimensions requires manual operation, which is not only difficult to operate, but also easy to produce differences due to different techniques of different testers. The efficiency is low and it is not suitable for industrial large-scale tensile sample testing.

[0058] Related metal tensile specimen testing methods include:

[0059] In the process of vision-based measurement of the original diameter of metal tensile specimens, a camera is introduced to measure the size before the tensile test. However, it is only a static measurement and cannot dynamically monitor the tensile process. Moreover, manual intervention is still required to measure the elongation and cross-sectional shrinkage after fracture.

[0060] The high temperature environment metal material tensile test system is based on the speckle principle and detects the strain of the tensile process through a DIC (Digital Image Correlation) camera. It cannot realize the sample clamping alignment detection, sample original size measurement and cross-sectional shrinkage rate measurement.

[0061] In order to measure the elongation of the steel bar, the detection device for the elongation of the ribbed steel bar tensile test needs to train the collected images using the training module and the machine learning module before the formal test. This method can only measure the elongation, but not the post-fracture shrinkage. In addition, each time the type of tensile sample is changed, the image training needs to be re-performed, which is a complicated process.

[0062] The above-mentioned metal tensile testing methods have not been able to simultaneously realize the integrated automated testing of metal tensile sample clamping and centering detection, original size measurement, and post-fracture elongation and cross-sectional shrinkage measurement, and cannot significantly improve the efficiency and accuracy of industrial large-scale sample testing.

[0063] In order to solve the above technical problems, the embodiments of the present invention provide a metal tensile testing system and a metal tensile specimen detection method. Through orthogonally arranged cameras integrated on a universal testing machine and a data acquisition and processing device, the sample clamping alignment confirmation and the measurement of the original size of the metal tensile sample are realized. After the tensile test, the fracture size is measured to obtain the elongation and cross-sectional shrinkage of the metal tensile sample. No human intervention is required, which avoids errors caused by manual measurement, improves detection accuracy and efficiency, and is suitable for industrial large-scale sample detection.

[0064] This embodiment provides a metal tensile testing system. Figure 1-2 As shown, it includes: a universal testing machine 101, a first camera 102, a second camera 103, a metal tensile sample 104 and a data acquisition and processing device 105, the universal testing machine 101 includes an upper fixture 106, a lower fixture 107 and an extensometer 108; the first camera 102 is located on the left or right side of the metal tensile sample 104, the second camera 103 is located in front of the metal tensile sample 104, the first camera 102 and the second camera 103 are arranged orthogonally, the upper fixture 106 and the lower fixture 107 respectively fix and clamp the upper end and the lower end of the metal tensile sample 104, the extensometer 108 is located in the gauge length stretching section of the metal tensile sample 104, and the data acquisition and processing device 105 is respectively connected to the extensometer 108, the universal testing machine 101, the first camera 102 and the second camera 103;

[0065] The data acquisition and processing device 105 is used to obtain the gauge length stretching section image of the metal tensile sample before the tensile test sent by the first camera 102 and the second camera 103, determine the initial cross-sectional size of the metal tensile sample and the initial edge line of the gauge length stretching section based on the gauge length stretching section image of the metal tensile sample before the tensile test, and clamp and center the metal tensile sample 104.

[0066] Specifically, an upper gauge length and a lower gauge length are provided at the upper end and the lower end of the metal tensile sample 104 , and a sample area between the upper gauge length and the lower gauge length serves as a gauge length tensile section.

[0067] Furthermore, in order to ensure the accuracy of measurement, the first camera 102 and the second camera 103 use high-speed cameras with a frame rate of 200 frames per second and an image resolution of up to 4 million pixels. The high resolution ensures clear capture of the edge of the sample, and frequent sampling also ensures the recording of key moments in the dynamic process.

[0068] Furthermore, before the tensile test of the metal tensile sample 104, the universal testing machine 101 and the power supply are turned on, the two ends of the metal tensile sample 104 are fixed with the upper clamp 106 and the lower clamp 107, and the gauge length tensile section of the metal tensile sample is photographed using the first camera 102 and the second camera 103 respectively, and the collected gauge length tensile section image of the metal tensile sample before the tensile test is transmitted to the data acquisition and processing device 105.

[0069] The extensometer 108 is used to collect the deformation of the metal tensile sample 104 during the tensile test of the metal tensile sample 104 until the deformation of the metal tensile sample meets the deformation threshold.

[0070] Specifically, after the metal tensile sample 104 is clamped and centered, and the initial cross-sectional dimensions of the metal tensile sample and the initial edge line of the gauge stretching section are measured, the extensometer 108 is clamped to the gauge stretching section of the metal tensile sample to start the tensile test; during the tensile test, the extensometer 108 can measure the deformation of the metal tensile sample in real time, and the measurement results can be processed by a computer to display the current sample deformation on a display.

[0071] Furthermore, assuming that the deformation threshold is 0.3%, when the deformation of the metal tensile sample is greater than 0.3%, the extensometer 108 is gently removed while minimizing interference with the tensile test; after the extensometer 108 is removed, the first camera 102 and the second camera 103 are started to continuously take pictures of the metal tensile sample 104 during the tensile test until the metal tensile sample 104 is broken and the experiment is completed.

[0072] The data acquisition and processing device 105 is also used to obtain the gauge length stretching section image of the metal tensile sample after the tensile fracture, determine the fracture cross-sectional size of the metal tensile sample and the fractured edge line of the gauge length stretching section based on the gauge length stretching section image of the metal tensile sample after the tensile fracture, and determine the metal tensile performance index based on the initial cross-sectional size, initial edge line, fracture cross-sectional size and fractured edge line; wherein, the gauge length stretching section image of the metal tensile sample after the tensile fracture is an image captured by the first camera 102 and the second camera 103 when the deformation of the metal tensile sample meets the deformation threshold.

[0073] Specifically, the moment when the stress sensor of the universal testing machine 101 detects a sudden decrease in stress (>50%) is taken as the moment when the metal tensile sample 104 breaks, and the data acquisition and processing device 105 extracts it. The first camera 102 and the second camera 103 respectively collect 5 to 10 images of the gauge length stretching section of the metal tensile sample after the tensile fracture, which are closest to the moment when the metal tensile sample 104 breaks. The data acquisition and processing device 105 obtains the image of the gauge length stretching section of the metal tensile sample after the tensile fracture.

[0074] A metal tensile testing system provided in this embodiment ensures that the metal tensile sample meets the clamping requirements of the tensile test and ensures the smooth progress of the experiment by clamping and centering the metal tensile sample. Secondly, through two orthogonally arranged cameras, the collection of the gauge length tensile section images of the metal tensile sample before the tensile test and after fracture is realized, and the initial cross-sectional size, initial edge line, fracture cross-sectional size and post-fracture edge line are determined based on the gauge length tensile section images of the metal tensile sample before the tensile test and after fracture, and then the metal tensile performance index is determined through the initial cross-sectional size, initial edge line, fracture cross-sectional size and post-fracture edge line, thereby realizing the automatic measurement of the metal tensile performance index, effectively avoiding measurement errors or deviations caused by manual operation, ensuring the consistency of the metal tensile test results, improving the detection efficiency and accuracy, and being suitable for large-scale sample detection.

[0075] According to an embodiment of the present invention, an embodiment of a metal tensile specimen testing method is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0076] In this embodiment, a metal tensile test specimen detection method is provided, which can be used in the data acquisition and processing device 105 in the above metal tensile test system. Figure 3 is a flow chart of a metal tensile specimen detection method according to an embodiment of the present invention. Figure 3 As shown, the process includes the following steps:

[0077] Step S301, obtaining a gauge length stretching segment image of a metal tensile sample before a tensile test, and determining an initial cross-sectional size of the metal tensile sample and an initial edge line of the gauge length stretching segment based on the gauge length stretching segment image of the metal tensile sample before the tensile test.

[0078] Specifically, before the tensile test of the metal tensile sample 104, the universal testing machine 101 and the power supply are turned on, the two ends of the metal tensile sample 104 are fixed with the upper clamp 106 and the lower clamp 107, and the gauge length tensile section of the metal tensile sample is photographed using the first camera 102 and the second camera 103 respectively, and the collected gauge length tensile section image of the metal tensile sample before the tensile test is transmitted to the data acquisition and processing device 105.

[0079] Step S302, clamping and centering the metal tensile sample based on the initial edge line of the gauge length tensile section.

[0080] Step S303, obtaining an image of a gauge length stretching section after the metal tensile sample is stretched and fractured, and determining the fracture cross-sectional size of the metal tensile sample and the edge line after fracture of the gauge length stretching section based on the image of the gauge length stretching section after the metal tensile sample is stretched and fractured.

[0081] Specifically, after the metal tensile sample 104 is clamped and centered, and the initial cross-sectional dimensions of the metal tensile sample and the initial edge line of the gauge stretching section are measured, the extensometer 108 is clamped to the gauge stretching section of the metal tensile sample to start the tensile test; during the tensile test, the extensometer 108 can measure the deformation of the metal tensile sample in real time. Assuming that the deformation threshold is 0.3%, when the deformation of the metal tensile sample is greater than 0.3%, the extensometer 108 is gently removed while minimizing interference with the tensile test; after the extensometer 108 is removed, the first camera 102 and the second camera 103 are started to continuously take pictures of the metal tensile sample 104 during the tensile test until the metal tensile sample 104 is broken and the experiment is completed.

[0082] Furthermore, the moment when the stress sensor of the universal testing machine 101 detects a sudden decrease in stress (>50%) is taken as the moment when the metal tensile sample 104 breaks, and the data acquisition and processing device 105 extracts and respectively collects 5 to 10 images of the gauge length stretching section of the metal tensile sample after the tensile fracture, which are closest to the moment when the metal tensile sample 104 breaks, by the first camera 102 and the second camera 103. The data acquisition and processing device 105 obtains the image of the gauge length stretching section of the metal tensile sample after the tensile fracture.

[0083] Step S304, determining the metal tensile performance index based on the initial cross-sectional size, the initial edge line, the fracture cross-sectional size and the fractured edge line; the metal tensile performance index includes the fractured elongation and the cross-sectional shrinkage.

[0084] A metal tensile specimen detection method provided in the present embodiment avoids the defect that the metal tensile test cannot realize the clamping and centering detection of the metal tensile specimen by clamping and centering the metal tensile specimen, ensures that the metal tensile specimen meets the clamping requirements of the tensile test, and ensures the smooth progress of the experiment; secondly, based on the gauge length tensile segment image of the metal tensile specimen before the tensile test and after fracture, the initial cross-sectional size, initial edge line, fracture cross-sectional size and post-fracture edge line are determined, and then the metal tensile performance index is determined through the initial cross-sectional size, initial edge line, fracture cross-sectional size and post-fracture edge line, thereby realizing the automatic measurement of the metal tensile performance index, effectively avoiding the measurement error or deviation caused by manual operation, ensuring the consistency of the metal tensile test results, and improving the detection efficiency and accuracy.

[0085] In this embodiment, a metal tensile test specimen detection method is provided, which can be used in the data acquisition and processing device 105 in the above metal tensile test system. Figure 4 is a flow chart of a metal tensile specimen detection method according to an embodiment of the present invention. Figure 4 As shown, the process includes the following steps:

[0086] Step S401, obtaining a gauge length stretching segment image of a metal tensile sample before a tensile test, and determining an initial cross-sectional size of the metal tensile sample and an initial edge line of the gauge length stretching segment based on the gauge length stretching segment image of the metal tensile sample before the tensile test.

[0087] Specifically, the above step S401 includes:

[0088] Step S4011, performing image processing on the gauge length stretching segment image of the metal tensile sample before the tensile test to obtain an initial target image.

[0089] Specifically, grayscale conversion is performed on the image of the gauge length stretching section of the metal tensile sample before the tensile test to obtain a grayscale image; denoising is performed on the grayscale image; and threshold segmentation is performed on the denoised image.

[0090] Furthermore, threshold segmentation is to judge whether each pixel in the image belongs to the foreground (marker line, edge line) or the background by comparing the gray value of the image with the set threshold; based on the adaptive threshold segmentation algorithm, the optimal threshold can be automatically selected to ensure robustness to sample images under different lighting conditions.

[0091] Furthermore, the optimal threshold is calculated based on the histogram distribution of each frame in the denoised image, and the threshold can be automatically selected without human intervention. If the illumination or sample surface features change during the experiment, the threshold can be automatically updated to ensure segmentation accuracy. The automatic calculation and dynamic adjustment improve the degree of measurement automation and environmental adaptability.

[0092] Step S4012: perform edge detection on the initial target image to determine the initial edge line of the gauge length stretching segment.

[0093] Specifically, the edge calculator determines the initial edge line of the gauge stretching section in the metal tensile sample by identifying the area of ​​sharp change in grayscale value in the initial target image; wherein, edge detection can adopt the Canny edge detection algorithm (one of the commonly used edge detection algorithms in the field of computer vision), which can reduce noise interference while ensuring accuracy, and realize automatic detection of the edge line of the sample, that is, the initial edge lines AB, CD, EF, GH of the gauge stretching section of the metal tensile sample captured by the first camera 102 and the second camera 103, as shown in Figure 5(a).

[0094] Step S4013, determining the initial cross-sectional dimensions of the metal tensile sample based on the midpoint of the initial edge line.

[0095] Specifically, calculate the midpoint J of the initial edge line AB, the midpoint K of the initial edge line CD, the midpoint M of the initial edge line EF and the midpoint N of the initial edge line GH; wherein the distance between point J and point K is the length JK, and the distance between point M and point N is MN, thereby obtaining the lengths of JK and MN, which are the original sizes of the metal tensile sample, that is, the initial cross-sectional size of the metal tensile sample.

[0096] Step S402, clamping and centering the metal tensile sample based on the initial edge line of the gauge length tensile section.

[0097] Specifically, the above step S402 includes:

[0098] Step S4021, obtaining the upper scale length and the lower scale length of the metal tensile sample, and determining a vertical line based on the midpoint of the upper scale length and the midpoint of the lower scale length.

[0099] Specifically, a vertical line PQ is drawn at the midpoint P of the upper scale length AC, and a vertical line RS is drawn at the midpoint R of the upper scale length EG.

[0100] Step S4022, calculating the angle between the initial edge line of the gauge length stretching section and the vertical line.

[0101] Specifically, the angle α between AB and PQ is calculated by the trigonometric function relationship, and the calculation formula is as follows:

[0102] α=arccos(PQ / AB)

[0103] The calculation formula of the angle β between the edge lines EF and RS is as follows:

[0104] β=arccos(RS / EF)

[0105] Step S4023, comparing the included angle with the preset angle, if the included angle does not match the preset angle, clamping and centering correction are performed on the metal tensile sample until the included angle matches the preset angle.

[0106] Specifically, assuming that the preset angle is 0.1°, if the angle α is less than 0.1° and the angle β is less than 0.1°, it is judged that the clamping of the metal tensile sample meets the alignment requirements of the tensile test; if the angle α is greater than 0.1°, or the angle β is greater than 0.1°, it is necessary to loosen the upper clamp 106 and then the lower clamp 107 of the metal tensile sample, and re-clamp and align the metal tensile sample until the requirements are met, thereby achieving clamping and alignment correction of the metal tensile sample 104.

[0107] Step S403, obtaining an image of the gauge length stretching section of the metal tensile sample after the tensile fracture, and determining the fracture cross-sectional size of the metal tensile sample and the edge line after the fracture of the gauge length stretching section based on the image of the gauge length stretching section of the metal tensile sample after the tensile fracture. Figure 3 Step S303 of the illustrated embodiment will not be described in detail here.

[0108] Step S404, determining the metal tensile performance index based on the initial cross-sectional size, initial edge line, fracture cross-sectional size and fractured edge line; the metal tensile performance index includes fractured elongation and cross-sectional shrinkage. Figure 3 Step S304 of the illustrated embodiment will not be described in detail here.

[0109] The present embodiment provides a method for detecting a metal tensile specimen, which performs image processing on an image of a gauge length stretching section of the metal tensile specimen before a tensile test, thereby improving the detection accuracy of edge detection, and by performing edge detection on the initial target image, automatically tracking and updating the initial edge line of the gauge length stretching section in real time are achieved, thereby ensuring accurate monitoring of sample deformation during the metal tensile test, avoiding manual adjustment of edge detection parameters, minimizing errors caused by human operation, and improving detection efficiency and accuracy; secondly, by calculating the angle between the initial edge line of the gauge length stretching section and the vertical line, the angle is compared with a preset angle, and based on the comparison result, the current clamping alignment of the metal tensile specimen is detected, and by performing clamping alignment correction on the metal tensile specimen, the defect that the metal tensile test cannot realize the clamping alignment detection of the metal tensile specimen is avoided, thereby ensuring that the metal tensile specimen meets the clamping requirements of the tensile test and ensuring the smooth progress of the experiment.

[0110] In this embodiment, a metal tensile test specimen detection method is provided, which can be used in the data acquisition and processing device 105 in the above metal tensile test system. Figure 6 is a flow chart of a metal tensile specimen detection method according to an embodiment of the present invention. Figure 6 As shown, the process includes the following steps:

[0111] Step S601, obtaining a gauge length stretching segment image of a metal tensile sample before the tensile test, and determining the initial cross-sectional dimensions of the metal tensile sample and the initial edge line of the gauge length stretching segment based on the gauge length stretching segment image of the metal tensile sample before the tensile test. Figure 4 Step S401 of the illustrated embodiment will not be described in detail here.

[0112] Step S602: clamp and center the metal tensile sample based on the initial edge line of the gauge length tensile segment. Figure 4 Step S402 of the illustrated embodiment will not be described in detail here.

[0113] Step S603, obtaining an image of a gauge length stretching section after the metal tensile sample is stretched and fractured, and determining the fracture cross-sectional size of the metal tensile sample and the edge line after fracture of the gauge length stretching section based on the image of the gauge length stretching section after the metal tensile sample is stretched and fractured.

[0114] Specifically, the above step S603 includes:

[0115] Step S6031, determining the post-fracture edge line and fracture morphology line of the gauge length stretching section based on the gauge length stretching section image after the metal tensile sample is stretched and fractured.

[0116] Specifically, as shown in Figure 7, the steps of determining the broken edge lines of the gauge stretching section are the same as the above-mentioned steps S4011 and S4012, and the gauge lines A'C', B'D', E'G' and F'H' after the metal tensile sample 104 is broken, and the broken edge lines A'J'B', C'K'D', E'M'F' and G'N'H' of the gauge stretching section of the metal tensile sample between the gauge lines are obtained.

[0117] Furthermore, a line segment at the fracture in the gauge length tensile segment image after the metal tensile sample is tensile fractured is used as a fracture morphology line.

[0118] Step S6032, determining the fracture cross-sectional size based on the intersection distance between the fractured edge line and the fracture morphology line.

[0119] Specifically, as shown in Figure 7, a horizontal line is drawn between the intersection points J' and K' of the edge line after fracture of the gauge length stretching section and the fracture morphology line, and the horizontal line intersects with the edge lines C'K'D' and A'J'B' of the metal tensile sample, and the average distance between the intersection points J' and K' is the fracture section size a; a horizontal line is drawn between the intersection points M' and N' of the edge line after fracture of the gauge length stretching section and the fracture morphology line, and the horizontal line intersects with the edge lines G'N'H' and E'M'F' of the metal tensile sample after fracture, and the average distance between the intersection points and M' and N' is the fracture section size b after fracture.

[0120] Step S604, determining the metal tensile performance index based on the initial cross-sectional size, the initial edge line, the fracture cross-sectional size and the fractured edge line; the metal tensile performance index includes the fractured elongation and the cross-sectional shrinkage.

[0121] Specifically, the above step S604 includes:

[0122] Step S6041, determining the average initial gauge length of the metal tensile sample based on the edge line length corresponding to the initial edge line.

[0123] Specifically, the metal tensile sample images taken by the first camera 102 and the second camera 103 are used to calculate the physical lengths of AB, CD, EF and GH by converting the ratio between the pixel coordinates and the actual physical size. As shown in FIG5(b), after the clamping and centering of the metal tensile sample 104 is confirmed, the average value of the lengths of the initial edge lines AB, CD, EF and GH is selected as the original gauge length L of the metal tensile sample. o(i.e. the initial gauge length average).

[0124] Step S6042, determining the average post-fracture gauge length of the metal tensile sample based on the edge line length corresponding to the post-fracture edge line.

[0125] Specifically, as shown in FIG. 7 , the average length of the edge lines A'J'B', C'K'D', E'M'F' and G'N'H' after breaking is taken as the average length L of the metal tensile sample after breaking. u .

[0126] Step S6043, calculating the elongation after breaking based on the average value of the initial gauge length and the average value of the gauge length after breaking.

[0127] Specifically, the calculation formula of the elongation after break A is as follows:

[0128] A=(L u -L o ) / L o ×100%

[0129] Step S6044, calculating the cross-sectional shrinkage rate based on the initial cross-sectional size and the fracture cross-sectional size.

[0130] Specifically, if the cross section of the metal tensile sample 104 is a circular cross section, the average value c of the initial cross-sectional dimensions JK and MN of the metal tensile sample is used as the average cross-sectional dimension of the metal tensile sample before the tensile test, and the average value c' of the fracture cross-sectional dimensions a and b is used as the average cross-sectional diameter dimension of the metal tensile sample after breaking. The calculation formula of the cross-sectional shrinkage Z is as follows:

[0131] Z=(c2-c'2) / c2*100%

[0132] Furthermore, if the cross section of the metal tensile sample 104 is a square cross section, the calculation formula of the cross section shrinkage rate Z is as follows:

[0133] Z=(JK*MN-a*b) / JK*MN*100%

[0134] A metal tensile specimen testing method provided in this embodiment calculates the elongation after fracture through the average value of the initial gauge length and the average value of the gauge length after fracture, and calculates the cross-sectional shrinkage rate through the initial cross-sectional size and the cross-sectional size after fracture, thereby realizing the cross-sectional size measurement of the metal tensile sample, and an integrated automated test of the elongation after fracture and the cross-sectional shrinkage rate measurement, without the need for human intervention, thus avoiding errors caused by manual measurement, and improving the detection accuracy and efficiency.

[0135] The specific steps of a metal tensile specimen testing method are described below through a specific embodiment.

[0136] Embodiment 1:

[0137] The elongation after fracture of 9 AlSi10Mg (cast aluminum alloy) tensile samples was tested by metal tensile test. The specific steps are as follows:

[0138] The circular cross-section tensile sample AlSi10Mg with marked gauge length is clamped and fixed on the universal testing machine by the upper clamp and the lower clamp; the first camera and the second camera are started to take pictures, and the edge detection is performed by the data acquisition and processing device; the proportional relationship between pixels and dimensions is determined by physical length calculation, and the original diameter of the sample is obtained to be 4.97mm, the gauge line distance is 30.20mm, and vertical lines PQ and RS are drawn.

[0139] The angle α between the initial edge line AB and PQ, and the angle β between the initial edge line EF and RS were calculated by a physical calculator; the angle α=0.07°, and the angle β=0.05°, and it was determined that the clamping of the metal tensile sample met the centering requirements of the tensile test.

[0140] Before the tensile test begins, the extensometer is first clamped to the gauge length tensile section of the tensile sample AlSi10Mg; when the deformation reaches 0.4%, the extensometer is gently removed without interfering with the tensile test as much as possible, and the first and second cameras are started to take pictures continuously until the metal tensile sample is broken and the experiment is completed.

[0141] The moment when the stress sensor of the universal testing machine detects that the stress suddenly drops from 447.9656N (unit: Newton) to -28.458N is the moment of fracture. At this time, the tensile test time is 127.1s. The data acquisition and processing device extracts 5 photos that are closest to this moment, which are collected by the first camera and the second camera respectively.

[0142] The data acquisition and processing device converts the image into a grayscale image through a grayscale conversion module, denoises the grayscale converted image through a filtering module, performs threshold segmentation on the filtered image through a threshold segmentation module, and performs edge detection on the image obtained by the threshold segmentation process through an edge calculator. The moment when the sample breaks is obtained through a physical length calculation module, and the average value of the gauge distance is 33.31 mm.

[0143] The elongation after break was calculated to be 10.3%. This process was repeated 8 times to complete the test of the remaining 8 samples, and the elongation after break of the other 8 samples was: 8.4%, 10.0%, 10.2%, 10.5%, 10.3%, 9.1%, 9.2%, 10.0%.

[0144] Embodiment 2:

[0145] The metal tensile test is used to measure the elongation and area reduction of TC4 (titanium alloy TC4 material) tensile samples. The specific steps are as follows:

[0146] The square section tensile sample TC4 with marked gauge length is clamped and fixed on the universal testing machine by the upper and lower clamps; the first camera and the second camera are started to take pictures, and the edge detection is performed by the data acquisition and processing device; the proportional relationship between pixels and dimensions is determined by physical length calculation, and the original cross-sectional dimensions of the sample are obtained as follows: 5.01 mm and 4.99 mm, the gauge line distance is 18.05 mm, and vertical lines PQ and RS are drawn.

[0147] The angle α between the edge lines AB and PQ, and the angle β between the edge lines EF and RS were calculated by a physical calculator; the angle α=0.03°, and the angle β=0.09°, and it was determined that the clamping of the metal tensile sample met the centering requirements of the tensile test.

[0148] Before the tensile test begins, first clamp the extensometer to the gauge length stretching section of the tensile sample TC4. When the deformation reaches 0.3%, gently remove the extensometer without interfering with the tensile test as much as possible. Start the first camera and the second camera to take pictures continuously until the metal tensile sample is broken and the experiment is completed.

[0149] The moment when the stress measured by the stress sensor of the universal testing machine suddenly dropped from 868.2355N to 16.83956N was the moment of fracture. At this time, the tensile test time was 109.9s. The data acquisition and processing device extracted 5 photos that were closest to this moment and were collected by the first camera and the second camera respectively.

[0150] The data acquisition and processing device converts the image into a grayscale image through the grayscale conversion module, denoises the grayscale converted image through the filtering module, performs threshold segmentation on the filtered image through the threshold segmentation module, and performs edge detection on the image obtained by the threshold segmentation process by the edge calculator. The moment when the sample breaks is obtained through the physical length calculation module. The average value of the gauge distance is 19.57 mm, the minimum cross-sectional size obtained by the first camera is 4.02 mm, and the minimum cross-sectional size obtained by the second camera is 3.97 mm. The calculation shows that the elongation after fracture is 8.4% and the cross-sectional shrinkage is 36.2%.

[0151] In this embodiment, a metal tensile specimen detection device is also provided, which is used to implement the above-mentioned embodiments and preferred implementation modes, and the descriptions that have been made will not be repeated. As used below, the term "module" can be a combination of software and / or hardware that implements a predetermined function. Although the device described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0152] This embodiment provides a metal tensile test specimen detection device, such as Figure 8 As shown, including:

[0153] An acquisition module 801 is used to acquire a gauge length stretching segment image of a metal tensile sample before a tensile test, and determine an initial cross-sectional size of the metal tensile sample and an initial edge line of the gauge length stretching segment based on the gauge length stretching segment image of the metal tensile sample before the tensile test;

[0154] A processing module 802 is used to perform clamping and centering processing on the metal tensile sample based on the initial edge line of the gauge length tensile section;

[0155] The first determination module 803 is used to obtain an image of a gauge length stretching section after the metal tensile sample is stretched and fractured, and determine the fracture cross-sectional size of the metal tensile sample and the edge line after the fracture of the gauge length stretching section based on the image of the gauge length stretching section after the metal tensile sample is stretched and fractured;

[0156] The second determination module 804 is used to determine the metal tensile performance index based on the initial cross-sectional size, the initial edge line, the fracture cross-sectional size and the post-fracture edge line; the metal tensile performance index includes the post-fracture elongation and the cross-sectional shrinkage.

[0157] In some optional implementations, the acquisition module 801 includes:

[0158] An image processing unit is used to process the image of the gauge length stretching section of the metal tensile sample before the tensile test to obtain an initial target image;

[0159] An edge detection unit, used for performing edge detection on the initial target image and determining an initial edge line of the gauge length stretching section;

[0160] The first determining unit is used to determine the initial cross-sectional size of the metal tensile sample based on the midpoint of the initial edge line.

[0161] In some optional implementations, the processing module 802 includes:

[0162] a second determining unit, for obtaining an upper gauge length and a lower gauge length of the metal tensile sample, and determining a vertical line based on a midpoint of the upper gauge length and a midpoint of the lower gauge length;

[0163] A first calculation unit is used to calculate the angle between the initial edge line of the gauge length stretching section and the vertical line;

[0164] The correction unit is used to compare the included angle with the preset angle. If the included angle does not match the preset angle, the metal tensile sample is clamped and centered until the included angle matches the preset angle.

[0165] In some optional implementations, the first determining module 803 includes:

[0166] A third determining unit is used to determine the post-fracture edge line and the fracture morphology line of the gauge length stretching section based on the gauge length stretching section image after the metal tensile sample is stretched and fractured;

[0167] The fourth determining unit is used to determine the fracture cross-sectional size based on the intersection distance between the post-fracture edge line and the fracture morphology line.

[0168] In some optional implementations, the second determining module 804 includes:

[0169] a fifth determining unit, configured to determine an initial gauge length average value of the metal tensile sample based on an edge line length corresponding to the initial edge line;

[0170] A sixth determining unit, configured to determine an average post-fracture gauge length of the metal tensile sample based on an edge line length corresponding to the post-fracture edge line;

[0171] A second calculation unit is used to calculate the elongation after breaking based on the average value of the initial gauge length and the average value of the gauge length after breaking;

[0172] The third calculation unit is used to calculate the cross-sectional shrinkage rate based on the initial cross-sectional size and the fracture cross-sectional size.

[0173] The further functional description of each of the above modules and units is the same as that of the above corresponding embodiments and will not be repeated here.

[0174] In this embodiment, a metal tensile specimen testing device is presented in the form of a functional unit, where the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that executes one or more software or fixed programs, and / or other devices that can provide the above functions.

[0175] The embodiment of the present invention also provides a computer device having the above Figure 8 A metal tensile specimen testing device is shown.

[0176] See also Fig. 9 , Fig. 9 is a schematic diagram of the structure of a computer device provided by an optional embodiment of the present invention, such as Fig. 9As shown, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process instructions executed in the computer device, including instructions stored in or on the memory to display the graphical information of the GUI on an external input / output device (such as a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Fig. 9 A processor 10 is taken as an example.

[0177] The processor 10 may be a central processing unit, a network processor or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0178] The memory 20 stores instructions executable by at least one processor 10, so that the at least one processor 10 executes the method shown in the above embodiment.

[0179] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely arranged relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0180] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid state drive; the memory 20 may also include a combination of the above types of memory.

[0181] The computer device also includes an input device 30 and an output device 40. The processor 10, the memory 20, the input device 30 and the output device 40 may be connected via a bus or other means. Fig. 9 The example of connecting through bus is taken in the following.

[0182] The input device 30 can receive input digital or character information, and generate key signal input related to the user settings and function control of the computer device, such as a touch screen, a keypad, a mouse, a track pad, a touch pad, an indicator bar, one or more mouse buttons, a trackball, a joystick, etc. The output device 40 may include a display device, an auxiliary lighting device (e.g., an LED) and a tactile feedback device (e.g., a vibration motor), etc. The above-mentioned display device includes but is not limited to a liquid crystal display, a light emitting diode, a display and a plasma display. In some optional embodiments, the display device can be a touch screen.

[0183] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0184] A part of the present invention may be applied as a computer program product, such as a computer program instruction, which, when executed by a computer, can call or provide the method and / or technical solution according to the present invention through the operation of the computer. Those skilled in the art should understand that the existence of the computer program instruction in a computer-readable medium includes, but is not limited to, a source file, an executable file, an installation package file, etc., and accordingly, the way in which the computer program instruction is executed by the computer includes, but is not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium may be any available computer-readable storage medium or communication medium accessible to the computer.

[0185] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A metal tensile testing system, characterized in that: include: A universal testing machine, a first camera, a second camera, a metal tensile sample and a data acquisition and processing device, wherein the universal testing machine includes an upper fixture, a lower fixture and an extensometer; The first camera is located on the left or right side of the metal tensile sample, the second camera is located in front of the metal tensile sample, the first camera and the second camera are arranged orthogonally, the upper clamp and the lower clamp respectively fix the upper end and the lower end of the metal tensile sample, the extensometer is located in the gauge length stretching section of the metal tensile sample, and the data acquisition and processing device is respectively connected to the extensometer, the universal testing machine, the first camera and the second camera; The data acquisition and processing device is used to obtain the gauge length stretching segment image of the metal tensile sample before the tensile test sent by the first camera and the second camera, determine the initial cross-sectional size of the metal tensile sample and the initial edge line of the gauge length stretching segment based on the gauge length stretching segment image of the metal tensile sample before the tensile test, and perform clamping and centering processing on the metal tensile sample; The extensometer is used to collect the deformation of the metal tensile sample during the tensile test of the metal tensile sample until the deformation of the metal tensile sample meets the deformation threshold; The data acquisition and processing device is also used to obtain an image of a gauge length stretching section of a metal tensile sample after tensile fracture, determine the fracture cross-sectional size of the metal tensile sample and the fractured edge line of the gauge length stretching section based on the image of the gauge length stretching section of the metal tensile sample after tensile fracture, and determine the metal tensile performance index based on the initial cross-sectional size, the initial edge line, the fracture cross-sectional size and the fractured edge line; wherein the image of the gauge length stretching section of the metal tensile sample after tensile fracture is an image captured by the first camera and the second camera when the deformation of the metal tensile sample meets the deformation threshold.

2. A metal tensile specimen detection method, characterized in that: A data acquisition and processing device used in a metal tensile testing system as claimed in claim 1; the method comprising: Acquire a gauge length stretching section image of the metal tensile sample before the tensile test, and determine an initial cross-sectional size of the metal tensile sample and an initial edge line of the gauge length stretching section based on the gauge length stretching section image of the metal tensile sample before the tensile test; Performing clamping and centering processing on the metal tensile sample based on the initial edge line of the gauge length tensile section; Acquire a gauge length stretching section image after the metal tensile sample is stretched and fractured, and determine the fracture cross-sectional size of the metal tensile sample and the edge line after fracture of the gauge length stretching section based on the gauge length stretching section image after the metal tensile sample is stretched and fractured; The metal tensile performance index is determined based on the initial cross-sectional size, the initial edge line, the fracture cross-sectional size and the post-fracture edge line; the metal tensile performance index includes post-fracture elongation and cross-sectional shrinkage.

3. The method according to claim 2, characterized in that The method of determining the initial cross-sectional size of the metal tensile sample and the initial edge line of the gauge length tensile section based on the gauge length tensile section image of the metal tensile sample before the tensile test comprises: Performing image processing on the gauge length stretching segment image of the metal tensile sample before the tensile test to obtain an initial target image; Performing edge detection on the initial target image to determine the initial edge line of the gauge length stretching section; The initial cross-sectional dimensions of the metal tensile specimen are determined based on the midpoint of the initial edge line.

4. The method according to claim 2, characterized in that: The clamping and centering process of the metal tensile sample based on the initial edge line of the gauge length tensile section comprises: Obtaining an upper gauge length and a lower gauge length of the metal tensile sample, and determining a vertical line based on a midpoint of the upper gauge length and a midpoint of the lower gauge length; Calculating the angle between the initial edge line of the gauge length stretching section and the vertical line; The included angle is compared with a preset angle. If the included angle does not match the preset angle, the metal tensile sample is clamped and aligned and corrected until the included angle matches the preset angle.

5. The method according to claim 2, characterized in that: The method of determining the fracture cross-sectional size of the metal tensile sample and the post-fracture edge line of the gauge length tensile section based on the gauge length tensile section image after the metal tensile sample is tensile fractured comprises: Determine the post-fracture edge line and fracture morphology line of the gauge length stretching section based on the gauge length stretching section image after the metal stretching sample is stretched and fractured; The fracture cross-sectional size is determined based on the intersection distance between the fracture rear edge line and the fracture topography line.

6. The method according to claim 2, characterized in that The determining of the metal tensile performance index based on the initial cross-sectional size, the initial edge line, the fracture cross-sectional size and the post-fracture edge line comprises: Determining an initial gauge length average value of the metal tensile sample based on the edge line length corresponding to the initial edge line; Determine the average post-fracture gauge length of the metal tensile sample based on the edge line length corresponding to the post-fracture edge line; Calculate the elongation after break based on the initial gauge length average value and the gauge length after break average value; The cross-sectional shrinkage is calculated based on the initial cross-sectional size and the fractured cross-sectional size.

7. A metal tensile specimen detection device, characterized in that: The device comprises: An acquisition module, used for acquiring an image of a gauge length stretching section of a metal tensile sample before a tensile test, and determining an initial cross-sectional size of the metal tensile sample and an initial edge line of the gauge length stretching section based on the image of the gauge length stretching section of the metal tensile sample before the tensile test; A processing module, used for clamping and centering the metal tensile sample based on the initial edge line of the gauge length tensile section; A first determination module is used to obtain an image of a gauge length stretching section of a metal tensile sample after the metal tensile sample is stretched and fractured, and determine a fracture cross-sectional size of the metal tensile sample and a post-fracture edge line of the gauge length stretching section based on the image of the gauge length stretching section of the metal tensile sample after the metal tensile sample is stretched and fractured; The second determination module is used to determine the metal tensile performance index based on the initial cross-sectional size, the initial edge line, the fracture cross-sectional size and the post-fracture edge line; the metal tensile performance index includes post-fracture elongation and cross-sectional shrinkage.

8. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the metal tensile specimen detection method according to any one of claims 2 to 6 by executing the computer instructions.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the metal tensile specimen detection method according to any one of claims 2 to 6.

10. A computer program product, characterized in that The method comprises computer instructions, wherein the computer instructions are used to cause a computer to execute the metal tensile specimen detection method according to any one of claims 2 to 6.

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