CN113129259A - Casting blank density detection method and system and electronic equipment - Google Patents
Casting blank density detection method and system and electronic equipment Download PDFInfo
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Abstract
The invention provides a method, a system and electronic equipment for detecting density of a casting blank, belonging to the technical field of continuous casting, wherein the method comprises the steps of scanning a contrast sample and a test sample by rays to form a gray level image of the contrast sample and a gray level image of the test sample; establishing a function of the gray value and the thickness of the comparison sample; acquiring thickness values corresponding to gray values of different positions of the test sample according to the function and the gray image of the test sample; thereby obtaining the density values of the test specimen in the width direction, and finally obtaining the surface-to-center density values of the test specimen. The method can realize density variation trend statistics from the surface to the center of the casting blank, and can achieve the technical effect of meeting the measurement of a large number of density variation trends.
Description
Technical Field
The invention relates to the technical field of continuous casting, in particular to a method and a system for detecting density of a casting blank and electronic equipment.
Background
The quality inspection of the continuous casting blank is an effective means for ensuring the production quality of the continuous casting, and the homogeneity, the component uniformity and the density of a solidification structure of the continuous casting blank are the quality evaluation standards of the continuous casting blank. In the process of casting blank solidification, the problems of looseness, lockhole, large-size segregation and the like are generated in the central area along with the reduction of density. However, an effective detection method for the density from the surface to the center of a cast slab is currently lacking.
In the prior art, density detection is performed by an OPA (in situ Analysis) technology, direct density weighing or industrial CT; among them, the OPA technique is a technique for analyzing the chemical composition and structure of an original state of an object to be analyzed. By carrying out high-speed data acquisition and analysis on spectral signals generated by spark discharge without pre-burning and continuously scanning excitation, the chemical components and content of the sample surface in an original state and the structural information of the surface can be measured, so that the component distribution, defect judgment and inclusion state analysis of the measured sample can be realized, and the density of the casting blank surface at different positions can be obtained in an apparent density mode. The method for directly weighing the density is to measure the density of the sample block by adopting the Archimedes principle so as to convert the density into the loose volume, and can also be directly used for evaluating the density. Industrial CT is a short term for industrial computed tomography, and can clearly, accurately and directly show the internal structure, composition, material and defect conditions of an object to be detected in the form of a two-dimensional tomographic image or a three-dimensional stereoscopic image without damaging the object to be detected, wherein the defect conditions include density factors such as voids. However, there are disadvantages as follows:
1) the OPA technology can only reflect the plane scanning result, and cannot reflect the internal density of the continuous casting billet, so that the density detection result is inaccurate; for the direct density weighing method, the detection result is greatly influenced by the size of the sample block, if the sample block is smaller, the measurement error is larger, and the measurement error cannot be eliminated by weighing for many times; in addition, the industrial CT also has a problem that the detection result is greatly affected by the size of the sample block, and the larger the sample block is, the larger the measurement error becomes.
2) The detection cost is high, and the customization requirement of density variation trend measurement under a large number of sample scenes cannot be met.
Therefore, a method for detecting the density of the casting blank with low detection cost and high detection efficiency is needed.
Disclosure of Invention
The invention aims to provide a method and a system for detecting the density of a casting blank and electronic equipment, and aims to solve the problems of high detection cost and low detection efficiency of the conventional detection method.
The invention discloses a method for detecting density of a casting blank, which comprises the following steps:
preparing a test sample of a casting blank and a comparison sample of the casting blank; wherein the thickness of the comparative sample is continuously varied;
respectively carrying out ray scanning on the contrast sample and the test sample to form a gray level image of the contrast sample and a gray level image of the test sample;
establishing a function of the gray value and the thickness of the comparison sample according to the thickness of the comparison sample and the gray image of the comparison sample;
acquiring thickness values corresponding to gray values of different positions of the test sample according to the function and the gray image of the test sample;
and acquiring a density evaluation value from the surface to the center of the test sample according to the thickness values corresponding to the gray values of different positions of the test sample, wherein the density evaluation value comprises a density value and/or a porosity value.
Further, preferably, the density value is represented by:
d is the density value, H is the thickness corresponding to any position of the test specimen, and H0 represents the thickness of the test specimen.
Further, it is preferable that the surface-to-center densitometric value of the test specimen is obtained from the densitometric value of the test specimen in the width direction;
the density value of the test specimen in the width direction is expressed as:
Dwthe average value of the densities corresponding to n positions is shown, and d represents the density at any point in the direction of the length of a certain width value.
Further, it is preferable that the test specimen is a three-dimensional ingot, wherein,
the test specimen has a thickness H0 of 10mm to 40mm, a width W0 of more than 20mm, and a length L0 of more than 30 mm.
Further, it is preferable that the sum of the lengths of the test specimens is greater than 500 mm.
Further, it is preferable that the comparative sample is a wedge-shaped cast slab, wherein,
the comparative sample had a thickness H0 of 20mm to 40mm and a width W0 of greater than 5 mm.
Further, it is preferable that a pitch between adjacent pixels of the gray image is less than 1 mm.
Further, preferably, the porosity of the test specimen is expressed as:
h is the thickness corresponding to any position of the test specimen, and H0 represents the thickness of the test specimen.
The invention also discloses a casting blank density detection system, which comprises a sample preparation unit, a ray scanning unit, a function establishing unit and a density evaluation value acquisition unit; wherein,
the sample preparation unit is used for preparing a test sample of a casting blank and a comparison sample of the casting blank; wherein the thickness of the comparative sample is continuously varied;
the ray scanning unit is used for respectively carrying out ray scanning on the contrast sample and the test sample to form a gray level image of the contrast sample and a gray level image of the test sample;
the function establishing unit is used for establishing a function of the gray value and the thickness of the comparison sample according to the thickness of the comparison sample and the gray image of the comparison sample;
the density evaluation value acquisition unit is used for acquiring thickness values corresponding to the gray values of different positions of the test sample according to the function and the gray image of the test sample; and acquiring a density evaluation value from the surface to the center of the test sample according to the thickness values corresponding to the gray values of different positions of the test sample, wherein the density evaluation value comprises a density value and/or a porosity value.
In addition, the present invention also protects an electronic device including:
at least one processor; and the number of the first and second groups,
a memory communicatively coupled to the at least one processor; wherein,
the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the steps of the method for detecting the density of the casting blank.
As described above, the method, the system and the electronic device for detecting the density of the casting blank according to the present invention have the following beneficial effects:
1. the density variation trend statistics from the surface to the center of the casting blank can be realized, and the customization requirements of measuring a large number of density variation trends can be met;
2. the detection aim can be realized by using conventional production equipment without preparing a special detection instrument, and the detection method is scientific, reasonable, simple and feasible, so that the detection cost is reduced;
3. by the measured porosity concept of any position, the comprehensive void volume in the volume of the test sample can be obtained, so that the average volume comprehensive porosity, namely the void volume contained in the unit test sample, is obtained, and the evaluation of the density of the casting blank is further realized.
To the accomplishment of the foregoing and related ends, one or more aspects of the invention comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative aspects of the invention. These aspects are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Further, the present invention is intended to include all such aspects and their equivalents.
Drawings
Other objects and results of the present invention will become more apparent and more readily appreciated as the same becomes better understood by reference to the following description and appended claims, taken in conjunction with the accompanying drawings. In the drawings:
FIG. 1 is a schematic structural diagram of a test sample of a casting blank density detection method according to an embodiment of the invention;
FIG. 2 is a gray scale diagram of a comparative sample of a method for detecting density of a casting blank according to an embodiment of the invention;
FIG. 3 is a gray scale and thickness variation trend chart of a comparative sample according to the casting blank density detection method provided by the embodiment of the invention;
FIG. 4 is a gray image of a test sample according to the method for detecting the density of a casting blank according to the embodiment of the invention;
FIG. 5 is a schematic diagram of a statistical method for density variation from the surface to the center of a casting blank of a test sample according to the casting blank density detection method of the embodiment of the invention;
FIG. 6 is a schematic diagram of the variation law of the density in different width directions of the casting blank density detection method according to the embodiment of the invention;
FIG. 7 is a density variation schematic diagram of a casting blank density detection method in different continuous casting processes according to an embodiment of the invention.
Detailed Description
In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more embodiments. It may be evident, however, that such embodiment(s) may be practiced without these specific details.
The method for detecting the density of the casting blank has the advantages of low cost and high detection efficiency, and is a method for quantitatively evaluating a continuous casting process on the density dimension by obtaining the thicknesses of different positions of the casting blank through the gray level images according to the principle that once a gap exists in the inner area of the casting blank, the gap is equivalent to the actual thickness of the casting blank and the attenuation degrees of rays penetrating through the casting blanks with different thicknesses are different, so that images with different gray levels are formed.
Various embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
Fig. 1 to 7 collectively describe a method for detecting the density of a cast slab. Specifically, fig. 1 is a schematic structural diagram of a test sample of a casting blank density detection method according to an embodiment of the invention; FIG. 2 is a gray scale diagram of a comparative sample of a method for detecting density of a casting blank according to an embodiment of the invention; FIG. 3 is a gray scale and thickness variation trend chart of a comparative sample according to the casting blank density detection method provided by the embodiment of the invention; FIG. 4 is a gray image of a test sample according to the method for detecting the density of a casting blank according to the embodiment of the invention; FIG. 5 is a schematic diagram of a statistical method for density variation from the surface to the center of a casting blank of a test sample according to the casting blank density detection method of the embodiment of the invention; fig. 6 is a schematic diagram of the variation law of the density in different width directions according to the method for detecting the density of the casting blank in the embodiment of the invention; fig. 7 is a schematic diagram of density change of a casting blank in different continuous casting processes according to the method for detecting density of the casting blank.
The method for detecting the density of the casting blank comprises the steps of S1-S5.
S1, preparing a test sample of the casting blank and a comparison sample of the casting blank; wherein the thickness of the comparative sample was continuously varied.
The test sample is a three-dimensional casting blank, wherein the thickness H0 of the test sample is 10-40 mm, the width W0 is more than 20mm, and the length L0 is more than 30 mm. The comparative sample is a wedge-shaped casting blank, wherein the thickness H0 of the comparative sample is 20-40 mm, and the width W0 is more than 5 mm.
Specifically, the length direction of the test specimen is set to coincide with the casting direction of the cast slab. And the precision in the thickness direction is less than +/-0.5 mm, namely the thickness H0 of the test sample is 10mm +/-0.5 mm-40 mm +/-0.5 mm, and further, in the aspect of processing the gray level image of the finally obtained test sample after subsequent ray scanning, the boundary is identified to obtain the standard that the difference of the thickness distribution on the boundary is less than 0.5 mm.
Through setting up the contrast sample into the wedge casting blank, and then realize the thickness continuous variation of contrast sample. It should be noted that the thickness variation covers at least the maximum thickness of the test sample to half of the test thickness to ensure the accuracy of gray scale to thickness within 0.2mm, i.e., the thickness H0 of the comparison sample is 20mm + -0.2 mm-40 mm + -0.2 mm.
It should be noted that the sum of the lengths of the test samples is greater than 500mm, specifically, since the quality of the casting blank in the drawing direction changes even under the same continuous casting process condition, and the density changes at the same width direction position, it is necessary to ensure that the statistical sample amount is sufficiently large to ensure that the density variation rule in the width direction can absolutely represent the continuous casting process, that is, the statistical density D has a sufficient length L in the drawing direction, and the length L is greater than 500 mm.
And S2, respectively carrying out ray scanning on the contrast sample and the test sample to form a gray scale image of the contrast sample and a gray scale image of the test sample.
In a specific implementation process, the radiation is X-rays, and can also be gamma rays and ultrasonic waves; in order to further ensure the density detection accuracy, the distance between adjacent pixels of the grayscale image is set to be less than 1 mm. That is, pixels are the minimum unit in the grayscale image processing; the pixel size of the grayscale image ensures that the actual distance separation between two pixels is less than 1.0 mm. Furthermore, in the gray scale picture processing of the final test sample, the identification of the boundary is taken as a standard to obtain that the thickness distribution has a difference of less than 0.5mm on the boundary.
And S3, establishing a function of the gray value and the thickness of the comparison sample according to the thickness of the comparison sample and the gray image of the comparison sample. Wherein the function of the gray value and the thickness of the comparison sample is expressed as:
h＝f(g)
wherein h is the thickness of any point, and g is the gray scale of any position corresponding to any point.
On a two-dimensional plane, a position function relation corresponding to the width W0 and the length L0 of the pixel and the test sample is established, namely, a gray scale relation of different positions is established.
Since the thickness of the contrast sample is continuously varied, scanning the contrast sample with the radiation will obtain a gray scale image of the contrast sample with continuously varying gray scale. And obtaining the change relation between the gray scale and the thickness of the contrast sample according to the continuously changed thickness of the contrast sample and the continuously changed gray scale in the gray scale image, and then obtaining the function of the gray scale value and the thickness of the contrast sample. In a specific implementation process, in order to ensure the accuracy of the gray scale-to-thickness function of the comparison sample, when the gray scale image of the comparison sample is used, the average value of the gray scales in the width direction of the same thickness is used as the gray scale value corresponding to the thickness.
And S4, acquiring thickness values corresponding to the gray values of different positions of the test sample according to the function and the gray image of the test sample.
Specifically, the thickness corresponding to an arbitrary position of the test sample can be obtained from the gray scale value and the thickness function of the comparison sample by the obtained gray scale image of the test sample.
It should be noted that, the thickness values corresponding to the gray values at different positions of the test sample are obtained according to the function and the gray image of the test sample. The thickness values of all the positions corresponding to the test sample are in the same graph
The thickness distribution corresponding to the gray image is obtained from the gray image according to the function of gray and thickness, the thickness of any point on the gray image is calculated as h, and obviously h is the thickness corresponding to any pixel (namely any position) in the area with the width W0 and the length L0.
In a specific implementation process, in order to ensure the accuracy of the gray scale to thickness function, the average value of the gray scales in the width direction of the same thickness is used as the gray scale value corresponding to the thickness.
And S5, acquiring a density evaluation value from the surface to the center of the test sample according to the thickness values corresponding to the gray values of different positions of the test sample, wherein the density evaluation value comprises a density value and/or a porosity value.
According to the thickness values corresponding to the gray values of different positions of the test sample, density values from the surface to the center of the test sample are obtained, and the density values are as follows:
d is the density value, H is the thickness corresponding to any position of the test specimen, and H0 represents the thickness of the test specimen.
The density value D is expressed by a value H/H0, obviously, the value 1 indicates that the position is completely compact, and the smaller the value is, the less compact and more loose the corresponding casting blank at the position is, the larger the gap contained in the casting blank is.
Obviously, the compactness along the line of the length L at different positions in the width direction, i.e. from the center of the surface of the cast slab, is different. If the continuous casting process is poor, the density curve is more tortuous closer to the central area of the casting blank.
And obtaining the density value from the surface to the center of the test sample according to the density value of the test sample in the width direction, wherein the smaller the variation amplitude of the density value from the surface to the center of the test sample is, namely the gentler the curve of the density value from the surface to the center of the test sample is, the better the homogeneity of the compactness dimension of the continuous casting process is, and the more reliable the continuous casting process is. Specifically, to obtain the variation rule of the density from the surface to the center of the casting blank in a continuous casting process, the density of the whole test sample at different positions in the width direction needs to be averaged to be used as the density from the surface to the center of the casting blank in the width direction.
By definition of the density, the thickness distribution obtained from the gray-scale image is converted into a density distribution d, which is obviously located in any region of the width W0 and the length L0What point. For a test sample, n pixel points (i.e., position points, corresponding to length L0) are arranged along the length direction at any width value in the width direction, and the average value of the densities corresponding to the n pixel points is recorded as DwWith DwAs the density of different positions in the width direction, the density variation of the test sample along the width direction is obtained.
The density value of the test specimen in the width direction is expressed as:
wherein D iswThe average value of the densities corresponding to n positions in the length direction is shown, and d represents the density at any point in the length direction of a certain width value.
That is, after the average value of the densities corresponding to n length positions in the length direction of a certain width value is taken as the density corresponding to the certain width value, the density distribution condition, that is, the density value from the surface to the center of the test sample can be obtained by listing the densities corresponding to all the width values, and the qualification degree of the continuous casting process of the test sample at the density angle is reflected. That is to say, under different continuous casting processes, density values from the surface to the center of the test sample, namely density variation trends of a casting blank from the surface to the center, are different, so that homogeneity of density dimensions corresponding to different continuous casting processes is different.
It should be further noted that, in order to ensure that the average value of the densities corresponding to n length positions in the length direction of a certain width value is taken as the accurate determination of the density corresponding to the certain width value, that is, to ensure that the number of n is large enough, the length of the test sample needs to be ensured. That is, the sum of the lengths of the test specimens is greater than 500 mm. If the length L0 of each test sample is less than 500mm, a plurality of test samples need to be tested under the condition of a specific continuous casting process, the total length L of the test samples must be more than 500mm, and the compactness D of all the test samples can be used as the quantitative evaluation of the compactness of the continuous casting process.
Examples are as follows: if the length L0 of each test specimen is 200mm, in order to quantitatively evaluate the compactness of the continuous casting process, it is necessary to take 3 test specimens under the conditions of the continuous casting process and then use D at any position in the width direction of the 3 test specimenswAs the density at this location. The length of the test specimen is 3 multiplied by 200mm, 600mm is larger than L (500mm), namely, the design requirement that the total length L of the test specimen must be larger than 500mm is met.
In a specific embodiment, the density D at a certain position in the width direction of each of the 3 test samples may be obtainedwThen taking 3 samples of density DwAs an evaluation of the compactness of the continuous casting process at this position in the width direction.
As a modification of this embodiment, the surface-to-center porosity of the test specimen is obtained according to the thickness values corresponding to the gray values at different positions of the test specimen.
When the thickness H is an absolute thickness, H0-H is the absolute comprehensive void at the position, so that the comprehensive void volume in the test sample can be obtained, and the comprehensive void volume/the test sample volume can be used as the porosity which can also be used as the evaluation index of the continuous casting process.
The porosity of the test specimen is expressed as:
where H is the thickness of the test specimen at any position, and H0 represents the thickness of the test specimen.
The porosity at any point can be used to obtain the bulk porosity of the test sample.
The thickness H is an absolute thickness, and H0-H is an absolute composite gap at the position.
In conclusion, the contrast sample and the test sample are scanned by rays to form a gray level image of the contrast sample and a gray level image of the test sample; establishing a function of the gray value and the thickness of the comparison sample according to the thickness of the comparison sample and the gray image of the comparison sample; acquiring thickness values corresponding to gray values of different positions of the test sample according to the function and the gray image of the test sample; and acquiring the density values of the test sample along the width direction according to the thickness values corresponding to the gray values of different positions of the test sample, and acquiring the density values of the test sample from the surface to the center according to the density values of the test sample along the width direction. The density variation trend statistics from the surface to the center of the casting blank can be realized, and the customization requirements of measuring a large number of density variation trends can be met.
Still take the continuous casting production of small square billets in a certain factory in China as an example, the section of the small square billet is 180mm multiplied by 180mm, and the operation process of the casting blank density detection method is concretely explained;
1. and preparing a sample, and taking a sample with the length of 1m along the drawing direction as the length of the sample for process evaluation aiming at each continuous casting process, so that the requirement that L is more than 500mm is met.
1.1 in the L direction, as shown in FIG. 1, a sample of the test specimen is taken. A 1m long sample was cut into 5 test samples of uniform length. Wherein, each test sample comprises 40mm of thickness H0 of the central position of the casting blank, 180mm of width W0 and 200mm of length L0. Wherein the processing precision of the test sample in the thickness direction is +/-0.25 mm.
The thickness of a 1.2 wedge-shaped comparison sample is continuously changed along with the change of steps, the comparison sample is made of a casting blank from the surface of the casting blank to a position far from the surface 1/4, the compactness is guaranteed, the highest position of the gradient is 40mm, and the lowest position of the gradient is 0 mm.
2. And respectively carrying out X-ray scanning on the contrast sample and the test sample to form a contrast sample gray image and a test sample gray image.
2.1 the contrast sample, after X-ray scanning, forms an image with continuously changing gray levels, as shown in fig. 2. Since there is always a difference in material structure, the gray level on one line of the same thickness is averaged as the gray level corresponding to this thickness, as shown by the gray level average at the same thickness in fig. 2 with a black line.
2.2 the test specimen was X-ray scanned and a gray scale image was formed as shown in fig. 4.
3. And establishing a function of the gray value and the thickness of the comparison sample according to the thickness of the comparison sample and the gray image of the comparison sample. From fig. 2, the relationship between the gray scale and the thickness of the comparison sample can be derived, which in turn is a function of the gray scale and the thickness of the comparison sample, as shown in fig. 3,
h＝f(g)
wherein h is the thickness of any point, and g is the gray scale of any corresponding position. According to the variation trend of the gray scale and the thickness of the comparison sample of fig. 3, a linear function of the gray scale and the thickness of the comparison sample is obtained.
And obtaining the thickness of the corresponding arbitrary position of the test sample according to the gray image in the graph of fig. 4 and the linear function of the gray value and the thickness of the comparison sample, thereby obtaining the density change of the arbitrary position. The gray lines W1 and W2 at two different width locations are selected on fig. 4 and are labeled as fig. 5, where line W1 is near the surface and line W2 is near the center of the slab. As is clear from observation of fig. 5, the grayscale images of the W1 line and the W2 line are different in the different width directions. The width of the W1 line is close to the surface of the casting blank, the gray value is small, the change amplitude is small, the width of the W2 line is close to the center of the casting blank, the gray value is large, and the change amplitude is large.
4. And acquiring the thickness values corresponding to the gray values of different positions of the test sample according to the function and the gray image of the test sample. And acquiring density values from the surface to the center of the test sample according to the thickness values corresponding to the gray values of different positions of the test sample.
4.1 obtaining the thickness value of each point of the W1 line and the W2 line according to the linear function h ═ f (g) of the gray value and the thickness;
4.2 correspondence of density and thickness values
The density values corresponding to the thicknesses of the respective point values of the W1 line and the W2 line were obtained, and a schematic diagram of the density variation rules in the W1 line width direction and the W2 line width direction was obtained, as shown in fig. 6. As can be seen from fig. 6, the densities of the same cast slab are different between the line W1 and the line W2 in different width directions. The density of the W1 line is close to the surface, the change amplitude is small, and the W2 line is close to the center of the casting blank, so that the loosening procedure in the casting blank is intensified, and the density change is large.
5. The density variation rules of two different continuous casting processes are detected according to the above manner, and a density variation schematic diagram under different continuous casting processes is obtained, as shown in fig. 7.
5.1 the density of 5 test samples with the length of 1m under the continuous casting process 1 is averaged at a certain position in the width direction to obtain a line A.
5.2 carrying out density averaging on 5 test samples with the length of 1m in total under the continuous casting process 2 at a certain position in the width direction to obtain a B line.
As can be seen from the figure, the two processes have different density variation trends from the surface to the center of the casting blank, the variation amplitude of the line A is larger, and the variation amplitude of the line B is smaller. Thus, it is clear that process 2 is superior to process 1 in terms of homogeneity in the density dimension.
As an improvement of this embodiment, the casting blank density detection may also be implemented by a machine learning model, and the casting blank density detection models are all classification models. The specific type of the classification model is, for example, a discriminant analysis model, an SVM model, a logistic model, a decision tree model, or the like.
It is to be understood that the described embodiments are for purposes of illustration only and that the scope of the appended claims is not limited to such structures.
The casting blank density detection program stored in the memory of the electronic device is a combination of a plurality of instructions, and when running in the processor, the method can realize that:
preparing a test sample of a casting blank and a comparison sample of the casting blank; wherein the thickness of the comparative sample is continuously varied;
respectively carrying out ray scanning on the contrast sample and the test sample to form a gray level image of the contrast sample and a gray level image of the test sample;
establishing a function of the gray value and the thickness of the comparison sample according to the thickness of the comparison sample and the gray image of the comparison sample;
acquiring thickness values corresponding to gray values of different positions of the test sample according to the function and the gray image of the test sample;
and acquiring a density evaluation value from the surface to the center of the test sample according to the thickness values corresponding to the gray values of different positions of the test sample, wherein the density evaluation value comprises a density value and/or a porosity value.
Specifically, the specific implementation method of the instructions by the processor may refer to the description of the relevant steps in the corresponding embodiment of the method for detecting the density of the casting blank, which is not described herein again.
Further, the electronic device integrated module/unit, if implemented in the form of a software functional unit and sold or used as a separate product, may be stored in a computer readable storage medium. The computer-readable medium may include: any entity or device capable of carrying said computer program code, recording medium, U-disk, removable hard disk, magnetic disk, optical disk, computer Memory, Read-Only Memory (ROM).
In the embodiments provided in the present invention, it should be understood that the disclosed apparatus, device and method can be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the modules is only one logical functional division, and other divisions may be realized in practice.
The modules described as separate parts may or may not be physically separate, and parts displayed as modules may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment.
However, it should be understood by those skilled in the art that various modifications may be made to the method, system and electronic device for detecting the density of a cast slab provided by the present invention without departing from the scope of the present invention. Therefore, the scope of the present invention should be determined by the contents of the appended claims.
Claims (10)
1. A method for detecting the density of a casting blank is characterized by comprising the following steps:
preparing a test sample of a casting blank and a comparison sample of the casting blank; wherein the thickness of the comparative sample is continuously varied;
respectively carrying out ray scanning on the contrast sample and the test sample to form a gray level image of the contrast sample and a gray level image of the test sample;
establishing a function of the gray value and the thickness of the comparison sample according to the thickness of the comparison sample and the gray image of the comparison sample;
acquiring thickness values corresponding to the gray values of different positions of the test sample according to the function and the gray image of the test sample;
and acquiring a density evaluation value from the surface to the center of the test sample according to the thickness values corresponding to the gray values of different positions of the test sample, wherein the density evaluation value comprises a density value and/or a porosity value.
2. The method for detecting the compactness of a cast slab according to claim 1,
the density values are expressed as:
d is the density value, H is the thickness corresponding to any position of the test specimen, and H0 represents the thickness of the test specimen.
3. The method for detecting the compactness of a cast slab according to claim 2,
obtaining a surface-to-center density value of the test specimen from the density value of the test specimen in the width direction;
the density value of the test specimen in the width direction is expressed as:
Dwthe average value of the densities corresponding to n positions in the length direction is shown, and d represents the density at any point in the length direction of a certain width value.
4. The method for detecting the compactness of a cast slab according to claim 3,
the test sample is a three-dimensional casting blank, wherein,
the thickness H0 of the test sample is 10 mm-40 mm, the width W0 is more than 20mm, and the length L0 is more than 30 mm.
5. The method for detecting the compactness of a cast slab according to claim 4,
the sum of the lengths of the test specimens is greater than 500 mm.
6. The method for detecting the compactness of a cast slab according to claim 1, wherein the reference sample is a wedge-shaped cast slab,
the comparative sample had a thickness H0 of 20mm to 40mm and a width W0 of greater than 5 mm.
7. The method for detecting the compactness of the casting blank according to claim 1, wherein the distance between adjacent pixels of the gray-scale image is less than 1 mm.
8. The method for detecting the compactness of the casting blank according to claim 1, wherein the porosity of the test sample is expressed as:
h is the thickness corresponding to any position of the test specimen, and H0 represents the thickness of the test specimen.
9. The casting blank density detection system is characterized by comprising a sample preparation unit, a ray scanning unit, a function establishing unit and a density evaluation value acquisition unit; wherein,
the sample preparation unit is used for preparing a test sample of a casting blank and a comparison sample of the casting blank; wherein the thickness of the comparative sample is continuously varied;
the ray scanning unit is used for respectively carrying out ray scanning on the contrast sample and the test sample to form a gray level image of the contrast sample and a gray level image of the test sample;
the function establishing unit is used for establishing a function of the gray value and the thickness of the comparison sample according to the thickness of the comparison sample and the gray image of the comparison sample;
the density evaluation value acquisition unit is used for acquiring thickness values corresponding to the gray values of different positions of the test sample according to the function and the gray image of the test sample; and acquiring a density evaluation value from the surface to the center of the test sample according to the thickness values corresponding to the gray values of different positions of the test sample, wherein the density evaluation value comprises a density value and/or a porosity value.
10. An electronic device, characterized in that the electronic device comprises:
at least one processor; and the number of the first and second groups,
a memory communicatively coupled to the at least one processor; wherein,
the memory stores instructions executable by the at least one processor to enable the at least one processor to perform the steps of the billet density detection method according to any one of claims 1 to 8.
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