High-performance nut connecting piece and preparation method thereof

Abstract

The invention relates to the technical field of nickel-based corrosion-resistant alloy preparation, in particular to a high-performance nut connecting piece and a preparation method thereof.The method comprises the steps that nickel-based corrosion-resistant alloy preparation raw materials are prepared, mixed and smelted according to the proportion to obtain nickel-based corrosion-resistant alloy liquid, the nickel-based corrosion-resistant alloy liquid is transferred into a preheated steel ladle, and the nickel-based corrosion-resistant alloy is obtained; the method comprises the following steps: casting nickel-based corrosion-resistant alloy liquid in a steel ladle into a continuous casting tundish, enabling the nickel-based corrosion-resistant alloy liquid to flow into a crystallizer, stirring the nickel-based corrosion-resistant alloy liquid in a crystallization process to obtain a solid nickel-based corrosion-resistant alloy, straightening the solid nickel-based corrosion-resistant alloy, collecting a nickel-based corrosion-resistant alloy casting blank gray-scale image and a nickel-based corrosion-resistant alloy casting blank hyperspectral image, and calculating the gray-scale image and the hyperspectral image of the nickel-based corrosion-resistant alloy casting blank. And the alloy texture confidence coefficient and the casting blank texture normative index are obtained, the stirring speed correction coefficient is calculated, the final nickel-based corrosion-resistant alloy continuous casting blank is obtained through continuous casting, and the high-performance nut connecting piece is prepared. The invention aims to improve the performance of the nut connecting piece and complete the preparation of the high-performance nut connecting piece.

Description

Technical Field

[0001] This invention relates to the field of nickel-based corrosion-resistant alloy preparation technology, specifically to a high-performance nut connector and its preparation method. Background Technology

[0002] With the development of science and technology, the performance requirements for nuts and bolts, one of the basic hardware components of scientific equipment, are gradually increasing. Currently, there are many materials available for manufacturing nuts and bolts, including copper, iron, manganese, and nickel. Among them, nickel-based corrosion-resistant alloys, with their superior high-temperature resistance and corrosion resistance, are widely used in the manufacture of nuts and bolts in aerospace, marine engineering, and other fields. Due to the increasing demand for high-performance nuts and bolts, the demand for nickel-based corrosion-resistant alloys is also gradually increasing. Traditionally, the production of large quantities of nickel-based corrosion-resistant alloy continuous casting billets mostly utilizes a combined electromagnetic stirring continuous casting method. A fixed parameter is set before the continuous casting process and the electromagnetic stirring process begin, allowing the continuous casting equipment to operate continuously, thereby reducing the production cycle and increasing the yield and efficiency of nickel-based corrosion-resistant alloys.

[0003] However, due to the complex production environment, if the electromagnetic stirring rate is not matched with the efficiency of the continuous casting process when the nickel-based corrosion-resistant alloy liquid is cooled, the alloy liquid is prone to uneven grain structure during the crystallization process. This eventually leads to cracks on the surface of the nickel-based corrosion-resistant alloy billet, affecting the quality of the billet and resulting in insufficient performance and strength of the high-performance nut connectors made of nickel-based corrosion-resistant alloy. Summary of the Invention

[0004] To address the aforementioned technical problems, the present invention aims to provide a high-performance nut connector and its manufacturing method, the specific technical solution of which is as follows:

[0005] In a first aspect, embodiments of the present invention provide a method for manufacturing a high-performance nut connector, the method comprising the following steps:

[0006] Raw material preparation: Prepare and mix the raw materials for nickel-based corrosion-resistant alloys according to the specified proportions;

[0007] Alloy smelting: The raw materials for preparing nickel-based corrosion-resistant alloys are smelted in an electric arc furnace to obtain a nickel-based corrosion-resistant alloy liquid;

[0008] Preheating and casting: The ladle is preheated to 1200℃; the nickel-based corrosion-resistant alloy liquid is transferred from the electric arc furnace to the preheated ladle, and then cast. The ladle is transported to the rotary table, which carries the ladle to the continuous casting tundish; the rotary table casts the nickel-based corrosion-resistant alloy liquid from the ladle into the continuous casting tundish, and the liquid flows into the crystallizer along the continuous casting tundish.

[0009] Electromagnetic stirring crystallization: A combined electromagnetic stirrer is installed on the crystallizer to stir the nickel-based corrosion-resistant alloy liquid during the crystallization process to obtain a solid nickel-based corrosion-resistant alloy.

[0010] Straightening: The straightening equipment of the continuous casting machine bends, stretches or compresses solid nickel-based corrosion-resistant alloys to obtain nickel-based corrosion-resistant alloy billets;

[0011] Grayscale images of nickel-based corrosion-resistant alloy billets were acquired and binarized to obtain the billet texture normality index of closed contours in the binary images. Hyperspectral images of nickel-based corrosion-resistant alloy billets were acquired, and the alloy texture confidence of linear textures was obtained based on the texture information in the hyperspectral images. Based on the billet texture normality index of all closed contours and the alloy texture confidence of all linear textures, the stirring speed correction coefficient was obtained, the speed of the electromagnetic stirrer was adjusted, and the final nickel-based corrosion-resistant alloy continuous casting billet was obtained by continuous casting.

[0012] High-performance nut connectors were prepared using the final nickel-based corrosion-resistant alloy continuous casting billet.

[0013] Preferably, the raw materials for preparing the nickel-based corrosion-resistant alloy include: carbon, nickel, chromium, molybdenum, copper, titanium, silicon, manganese, and iron.

[0014] Preferably, the mass percentage of each component in the raw material for preparing the nickel-based corrosion-resistant alloy is as follows:

[0015] Iron 27.80%, Chromium 20.40%, Molybdenum 2.81%, Copper 1.88%, Titanium 2.15%, Silicon 0.23%, Manganese 0.54%, Carbon 0.011%, Balance: Nickel and unavoidable impurities.

[0016] Preferably, the alloy is smelted at a temperature of 1500°C.

[0017] Preferably, the casting of the nickel-based corrosion-resistant alloy liquid includes a casting temperature range of 1200–1300°C.

[0018] Preferably, obtaining the slab texture normality index of the closed contour in the binary image includes:

[0019] Closed contours in a binary image are obtained using a contour tracking algorithm. The Euclidean distance between the pixel with the smallest horizontal coordinate and the pixel with the largest horizontal coordinate on the closed contour is recorded as the horizontal length. The Euclidean distance between the pixel with the smallest vertical coordinate and the pixel with the largest vertical coordinate on the closed contour is recorded as the vertical length. Closed contours with a horizontal length greater than their vertical length are recorded as horizontal closed contours, and vice versa.

[0020] Each closed contour is used as input to the shape context algorithm, and the shape context feature value of each pixel on each closed contour is output. The average of the shape context feature values ​​of all pixels on each closed contour is recorded as the shape feature value of each closed contour.

[0021] The absolute value of the difference between the morphological feature values ​​of each closed contour and the other closed contours is recorded as the morphological feature difference between each closed contour and the other closed contours. The average value of the morphological feature differences between each closed contour and the other closed contours is taken as the negative exponent of an exponential function with the natural constant as the base. The calculation result of the exponential function is taken as the contour morphological consistency.

[0022] The average gray value of all pixels within each closed contour is recorded as the mean within the contour, and the average gray value of all pixels within the smallest bounding rectangle of each closed contour is recorded as the overall mean.

[0023] The absolute value of the difference between the gray value of each pixel within the closed contour and the mean value within the contour is recorded as the individual local gray value difference. The average value of the individual local gray value differences of all pixels within the closed contour is recorded as the individual local gray value average difference. The absolute value of the difference between the mean value within the contour and the overall mean value is recorded as the overall local gray value difference. The product of the individual local gray value average difference and the overall local gray value difference is recorded as the gray value diversity index.

[0024] The weights of the longitudinal closed contour and the transverse closed contour are set to 2 and 1 respectively. The sum of the grayscale diversity index of each closed contour and the preset first adjustment parameter is recorded as the adjusted grayscale diversity index. The product of the adjusted grayscale diversity index and the weights is calculated. The ratio of the contour shape consistency to the product is recorded as the billet texture standardization index.

[0025] Preferably, obtaining the confidence level of the alloy texture with linear patterns based on the texture information in the hyperspectral image includes:

[0026] In a binary image, edge lines other than closed contours are denoted as linear textures.

[0027] The average reflectance of all pixels on each linear ridge in each band of the hyperspectral image of the nickel-based corrosion-resistant alloy billet is recorded as the mean reflectance of each linear ridge in each band. The mean reflectance of each linear ridge in all bands is used as the input of the least squares method to fit the band reflectance fitting curve of the output band.

[0028] Obtain all peak points on the band reflection fitting curve, record the peak point with the highest reflectivity as the optimal reflection band, and record the reflectivity of each pixel in the optimal reflection band as the representative reflectivity of each pixel.

[0029] Centered on each pixel on each linear texture, a neighborhood window with a preset side length is constructed. The ratio of the representative reflectance of each pixel to that of each pixel in the neighborhood window is recorded as the reflectance ratio. The difference between the value 1 and the reflectance ratio is recorded as the reflectance similarity. The sum of the reflectance similarities of each pixel to all pixels in the neighborhood window is recorded as the neighborhood reflectance consistency of each pixel. The sum of the neighborhood reflectance consistency of all pixels on each linear texture is recorded as the reflectance prominence index of each linear texture.

[0030] The heterogeneity of the hyperspectral curves for each linear ridge is represented as follows:

[0031]

[0032] Among them, Z j Let H represent the heterogeneity of the hyperspectral curve of the j-th linear ridge, where H is the number of linear ridges, and Y is the number of ridges. j,m Let be the minimum number of peak points on the band reflection fitting curves of the j-th and m-th linear ridges. Let be the band length of the b-th peak point on the band reflection fitting curve of the j-th linear ripple. Let be the band length of the b-th peak point on the band reflection fitting curve of the m-th linear ripple;

[0033] The product of the hyperspectral curve heterogeneity and the reflectance prominence index, plus a preset second adjustment parameter, is recorded as the degree of alloy texture anomaly, and the reciprocal of the degree of alloy texture anomaly is recorded as the alloy texture confidence level.

[0034] Preferably, the step of obtaining the stirring speed correction coefficient, adjusting the rotation speed of the electromagnetic stirrer, and continuously casting the final nickel-based corrosion-resistant alloy continuous casting billet includes:

[0035] The sum of the average of the normality index of the billet texture of all closed contours and the average of the confidence index of the alloy texture of all linear textures is denoted as the health assessment index.

[0036] Arrange the health assessment indices at all times in ascending order according to the acquisition time to construct a health assessment sequence. Use the health assessment sequence as the input of a BP neural network to output the stirring speed correction coefficient.

[0037] The stirring speed correction coefficient is used as the input of the PID controller. The PID controller adjusts the speed of the electromagnetic stirrer according to the stirring speed correction coefficient, and the final nickel-based corrosion-resistant alloy continuous casting billet is obtained by continuous casting.

[0038] Preferably, the preparation of high-performance nut connectors using the final nickel-based corrosion-resistant alloy continuous casting billet includes:

[0039] Cold heading: The final nickel-based corrosion-resistant alloy continuous casting billet is cold-headed;

[0040] Heat treatment: The cold-headed nickel-based corrosion-resistant alloy continuous casting billet is subjected to heat treatment, including but not limited to quenching and tempering;

[0041] Turning and threading: The heat-treated nickel-based corrosion-resistant alloy continuous casting billet is turned and threaded to obtain high-performance nut connectors;

[0042] Cleaning and polishing: Cleaning and polishing high-performance nut connectors;

[0043] Quality inspection: Quality inspection is performed on high-performance nut connectors, including but not limited to appearance, dimensions, thread accuracy, and hardness;

[0044] Packaging: High-performance nut connectors that meet quality inspection standards are packaged, including but not limited to boxed or bagged packaging.

[0045] Secondly, embodiments of the present invention also provide a high-performance nut connector, which is manufactured by any one of the high-performance nut connector manufacturing methods described in the present invention.

[0046] The present invention has at least the following beneficial effects:

[0047] First, the grayscale and morphological characteristics of surface cracks in nickel-based corrosion-resistant alloy continuously cast billets are analyzed based on grayscale images of the billets, obtaining the billet texture regularity index for each closed contour. Then, the reflectance characteristics of the nickel-based corrosion-resistant alloy continuously cast billet surface are analyzed based on hyperspectral images of the billets, obtaining the alloy texture confidence level for each linear crack. Finally, considering the different morphologies of surface cracks in the nickel-based corrosion-resistant alloy continuously cast billets, a health assessment index for the surface of the billets at each time point is constructed, improving the accuracy of surface defect assessment for nickel-based corrosion-resistant alloy continuously cast billets. Based on the health assessment index of the nickel-based corrosion-resistant alloy continuous casting billet surface at all times, the stirring speed correction coefficient is obtained. Combined with the PID controller, the stirring speed of the electromagnetic stirrer is adaptively controlled, thereby reducing the probability of crack formation on the surface of the nickel-based corrosion-resistant alloy continuous casting billet. This avoids the situation in the traditional continuous casting process using combined electromagnetic stirring where the continuous casting process and electromagnetic stirring speed are mismatched, resulting in more cracks on the surface of the continuous casting billet. This further improves the production efficiency and quality of the nickel-based corrosion-resistant alloy continuous casting process, thereby enhancing the preparation efficiency and performance of high-performance nut connectors. Attached Figure Description

[0048] To more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0049] Figure 1 A flowchart illustrating the steps of a method for manufacturing a high-performance nut connector according to an embodiment of the present invention;

[0050] Figure 2 This is a schematic diagram illustrating the acquisition of the health assessment index of the surface of a nickel-based corrosion-resistant alloy continuous casting billet. Detailed Implementation

[0051] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of a high-performance nut connector and its manufacturing method according to the present invention. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0053] The following description, in conjunction with the accompanying drawings, details a specific scheme for a high-performance nut connector and its manufacturing method provided by the present invention.

[0054] Please see Figure 1 The diagram illustrates a flowchart of a method for manufacturing a high-performance nut connector according to an embodiment of the present invention. The method includes the following steps:

[0055] Step S001: Preparation of nickel-based corrosion-resistant alloy materials.

[0056] In this embodiment, Incoloy 925 nickel-based corrosion-resistant alloy is used as the main continuous casting raw material. Incoloy 925 nickel-based corrosion-resistant alloy is developed by appropriately increasing the content of iron and chromium and reducing the content of nickel on the basis of nickel-based alloy. Its composition is as follows: iron 27.80%, chromium 20.40%, molybdenum 2.81%, copper 1.88%, titanium 2.15%, silicon 0.23%, manganese 0.54%, carbon 0.011%, and the balance is nickel and unavoidable impurities. For ease of description, Incoloy 925 nickel-based corrosion-resistant alloy will be referred to as nickel-based corrosion-resistant alloy.

[0057] Step S002: Nickel-based corrosion-resistant alloy billet is obtained by continuous casting of nickel-based corrosion-resistant alloy.

[0058] Alloy smelting: Add the nickel-based corrosion-resistant alloy to the converter and smelt it at 1500℃.

[0059] Preheating and casting: The ladle is preheated to 1200℃. After the nickel-based corrosion-resistant alloy is completely liquefied, the molten nickel-based corrosion-resistant alloy is transferred from the electric arc furnace to the preheated ladle. The molten nickel-based corrosion-resistant alloy is then cast at a temperature range of 1200-1300℃. The ladle is then transported to the rotary table, which carries the ladle to the continuous casting tundish. The rotary table pours the molten nickel-based corrosion-resistant alloy from the ladle into the continuous casting tundish, and the molten nickel-based corrosion-resistant alloy flows into the crystallizer along the continuous casting tundish.

[0060] Electromagnetic stirring crystallization: A combined electromagnetic stirrer is installed on the crystallizer to introduce an electromagnetic field into the nickel-based corrosion-resistant alloy liquid. During the crystallization process, the nickel-based corrosion-resistant alloy liquid is stirred, which helps to form a finer and more uniform grain structure, improves the mechanical properties and surface quality of the continuously cast billet, and obtains a solid nickel-based corrosion-resistant alloy.

[0061] Straightening: The straightening equipment of the continuous casting machine bends, stretches or compresses the solid nickel-based corrosion-resistant alloy according to the corresponding specification requirements and deviation information to adjust its shape and obtain the nickel-based corrosion-resistant alloy billet.

[0062] Step S003: Acquire grayscale images and hyperspectral images of nickel-based corrosion-resistant alloy billets.

[0063] A CMOS high-definition camera is installed at the discharge point of the straightening equipment of the continuous casting machine. At regular intervals, the camera takes pictures of the nickel-based corrosion-resistant alloy billet after continuous casting, and obtains images of the nickel-based corrosion-resistant alloy billet. The images of the nickel-based corrosion-resistant alloy billet are then processed into grayscale images to obtain grayscale images of the nickel-based corrosion-resistant alloy billet. The Laplacian operator is then used to sharpen the grayscale images of the nickel-based corrosion-resistant alloy billet, and wavelet denoising algorithm is used to denoise the grayscale images of the nickel-based corrosion-resistant alloy billet.

[0064] Meanwhile, a hyperspectral camera is installed at the discharge point of the straightening equipment of the continuous casting machine to image the nickel-based corrosion-resistant alloy billet after continuous casting at regular intervals, thereby obtaining a hyperspectral image of the nickel-based corrosion-resistant alloy billet.

[0065] In this embodiment, U = 1s. The Laplacian operator and wavelet denoising algorithm are well-known techniques and will not be described in detail here.

[0066] Thus, grayscale images and hyperspectral images of nickel-based corrosion-resistant alloy ingots were obtained.

[0067] Step S004: Obtain the billet texture normality index from the grayscale image of the nickel-based corrosion-resistant alloy billet, obtain the alloy texture confidence from the hyperspectral image of the nickel-based corrosion-resistant alloy billet, construct the health assessment index of the surface of the nickel-based corrosion-resistant alloy continuous casting billet, and calculate the stirring speed correction coefficient.

[0068] Traditional electromagnetic stirrers operate by setting fixed parameters. However, since continuous casting involves continuous pouring and cooling, the flow rate and temperature of the molten alloy may fluctuate. This can lead to a mismatch between the electromagnetic stirring rate and the efficiency of the continuous casting process, resulting in defects inside and outside the cast billet. These defects primarily manifest as transverse and longitudinal cracks, which appear as connected regions in the image. This embodiment uses a grayscale image and a hyperspectral image of a nickel-based corrosion-resistant alloy cast billet at a specific moment for analysis.

[0069] For the grayscale image of nickel-based corrosion-resistant alloy slab, the Canny edge detection operator is used to obtain the edge information in the grayscale image of the nickel-based corrosion-resistant alloy slab, resulting in a binary image of the nickel-based corrosion-resistant alloy slab. Then, the contour tracking algorithm is used to obtain the closed contour in the binary image of the nickel-based corrosion-resistant alloy slab. Each closed contour may be a crack contour on the continuously cast slab. However, the continuous casting process is not a finishing process. The surface of the continuously cast slab produced by the continuous casting process also has many alloy textures. These textures are usually caused by the stretching of the continuous casting process or the molding equipment in the process flow, and have a certain regularity. Cracks, on the other hand, are caused by the stress inside and outside the continuously cast slab, so their shape is mostly irregular and the depth is uneven. In the image, they appear as cracks with varying brightness. The texture of the alloy itself is generally shallow and mostly horizontal stripes.

[0070] To address the aforementioned characteristics, the Euclidean distance between the pixel with the smallest horizontal coordinate and the pixel with the largest horizontal coordinate on each closed contour is first used as the horizontal length of each closed contour. Then, the Euclidean distance between the pixel with the smallest vertical coordinate and the pixel with the largest vertical coordinate on each closed contour is used as the vertical length of each closed contour. Closed contours with a horizontal length greater than a vertical length are denoted as horizontal closed contours, and closed contours with a horizontal length less than or equal to a vertical length are denoted as vertical closed contours.

[0071] The horizontal and vertical weights of the vertical closed contours are set to 2, and the horizontal and vertical weights of the horizontal closed contours are set to 1. Each closed contour is used as input to the shape context algorithm, and the output is the shape context feature value of each pixel in each closed contour. The average of the shape context feature values ​​of all pixels in each closed contour is recorded as the morphological feature value of each closed contour, and the casting billet texture normality index is constructed.

[0072]

[0073]

[0074]

[0075]

[0076] In the formula, C i R is the slab texture regularity index for the i-th closed contour, α is an adjustment parameter to prevent the denominator from being 0, α = 0.001, and R i G is the gray-scale diversity index of the i-th closed contour. i To ensure the contour shape consistency of the i-th closed contour, exp() is an exponential function with the natural constant as its base. This is the average grayscale value of all pixels within the i-th closed contour. It is the average grayscale value of all pixels within the minimum bounding rectangle of the i-th closed contour. Let n be the grayscale value of the r-th pixel within the i-th closed contour. i ω is the number of pixels within the i-th closed contour. i S represents the horizontal and vertical weights of the i-th closed contour. z S is a set of vertically closed contours. h Let M be the set of horizontally closed contours, and v be the number of closed contours. i v represents the morphological feature value of the i-th closed contour. a This represents the morphological feature value of the a-th closed contour.

[0077] The smaller the difference in grayscale values ​​of pixels within a closed contour, and the smaller the difference in grayscale values ​​between the smallest bounding rectangle of the closed contour and the pixels within the closed contour, the smaller the grayscale difference inside and outside the closed contour. The smaller the grayscale diversity index value, the more likely it is the texture of the billet itself, and the larger the billet texture normalization index value. When the closed contour belongs to a set of vertical closed contours, it is more likely to be a crack contour, and the smaller the billet texture normalization index value, the more likely it is the texture of the billet itself. When the closed contour belongs to a set of horizontal closed contours, it is more likely to be the texture of the billet itself, and the larger the billet texture normalization index value. The smaller the difference in morphological feature values ​​between the closed contour and other closed contours, the more similar the closed contour is to the features of most closed contours. The larger the contour morphological consistency value, the more likely it is the texture of the billet itself, and the larger the billet texture normalization index value.

[0078] At this point, the standardization index of the billet texture for each closed contour is obtained.

[0079] Because the formation of cracks is highly irregular, resulting in cracks of varying thickness and not necessarily forming closed contours, in order to detect all cracks, the edge lines in the binary image of the nickel-based corrosion-resistant alloy billet other than the closed contours are recorded as linear lines.

[0080] Specifically, linear patterns may also be cracks or patterns on the billet itself. Cracks are usually finer, appearing as edges with many branches. Furthermore, the nickel-based corrosion-resistant alloy material in the cracked area is not uniform, and the corresponding hyperspectral data differs significantly from the hyperspectral data of uniform locations in other materials.

[0081] Based on the above characteristics, the average reflectance of all pixels on each linear ridge in each band of the hyperspectral image of the nickel-based corrosion-resistant alloy billet is denoted as the average reflectance of each linear ridge in each band, that is, the average reflectance of the j-th linear ridge in the k-th band. in, Let n be the reflectance of the m-th pixel on the j-th linear ridge in the k-th band. j Let be the number of pixels on the j-th linear ridge.

[0082] To avoid interference from random factors, the average reflectance of each linear texture across all bands is used as the input for the least squares method. A band reflection fitting curve is fitted to the output band, and all peaks on the curve are obtained. The peak with the highest reflectance is designated as the optimal reflection band, and the reflectance of each pixel in the optimal reflection band is designated as the representative reflectance of that pixel. The least squares method is a well-known technique and will not be elaborated upon in this embodiment. A neighborhood window with side length s is constructed centered on each pixel on the linear texture, and the alloy texture confidence of the linear texture is calculated.

[0083]

[0084]

[0085]

[0086] In the formula, W j B represents the confidence level of the alloy texture for the j-th linear ridge. j Z represents the reflectance prominence index of the j-th linear ridge. j Let represent the heterogeneity of the hyperspectral curve for the j-th linear ridge, δ be an adjustment parameter to prevent the denominator from being zero, δ = 0.001, H be the number of linear ridges, and Y be... j,m Let be the minimum number of peak points on the band reflection fitting curves of the j-th and m-th linear ridges. Let be the band length of the b-th peak point on the band reflection fitting curve of the j-th linear ripple. Let n be the band length of the b-th peak on the band reflection fitting curve of the m-th linear ripple. j Let s be the number of pixels on the j-th linear texture. 2 This represents the number of pixels within the neighborhood window. Let be the representative reflectance of the k-th pixel on the j-th linear ridge. Let be the representative reflectance of the l-th pixel within the neighborhood window of the k-th pixel on the j-th linear ridge.

[0087] The greater the difference between the band length of the peak point of each linear texture and the band length of the peak points of other linear textures, the higher the degree of anomaly of each linear texture, the greater the heterogeneity value of the hyperspectral curve, the more likely it is a crack edge, and the lower the confidence value of the alloy texture. The greater the difference in representative reflectance between each pixel on each linear texture and the other pixels in its neighborhood window, the more prominent each linear texture is, the greater the reflectance prominence index value, the more likely it is a crack edge, and the lower the confidence value of the alloy texture.

[0088] By combining the preformability index of the billet texture of all closed contours and the confidence level of the alloy texture of all linear patterns, a health assessment index for the surface of nickel-based corrosion-resistant alloy continuously cast billets is constructed:

[0089]

[0090] In the formula, g is the health assessment index of the surface of the nickel-based corrosion-resistant alloy continuous casting billet, M is the number of closed profiles, H is the number of linear lines, and C is the number of linear lines. i W is the standardization index of the billet texture for the i-th closed contour. j Let be the confidence level of the alloy texture for the j-th linear pattern.

[0091] A higher regularity index for the surface texture of all closed contours of a nickel-based corrosion-resistant alloy billet and a higher confidence level for the alloy texture of all linear lines indicate higher edge regularity, a lower probability of cracks, and better surface health. A higher health assessment index value indicates a higher degree of sustainability for the electromagnetic stirring continuous casting process. A schematic diagram illustrating the acquisition of the surface health assessment index for nickel-based corrosion-resistant alloy continuous casting billets is shown below. Figure 2 As shown.

[0092] Thus, the health assessment index of the surface of nickel-based corrosion-resistant alloy continuous casting billet was obtained.

[0093] Based on the grayscale and hyperspectral images of nickel-based corrosion-resistant alloy billets acquired at all times, the health assessment index of the surface of nickel-based corrosion-resistant alloy continuous casting billets at all times is obtained according to the above method. The health assessment indexes of the surface of nickel-based corrosion-resistant alloy continuous casting billets at all times are arranged in ascending order according to the acquisition time to construct a health assessment sequence.

[0094] The health assessment sequence is used as the input to the BP neural network. In this embodiment, the BP neural network selects SGD stochastic gradient descent as the optimization algorithm, uses cross-entropy as the loss function, and outputs the stirring speed correction coefficient.

[0095] Thus, the stirring speed correction coefficient is obtained.

[0096] Step S005: Adjust the stirring speed of the electromagnetic stirrer according to the stirring speed correction coefficient, and continuously cast the final nickel-based corrosion-resistant alloy continuous casting billet.

[0097] The stirring speed correction coefficient is used as the input to the PID controller. Based on this coefficient, the PID controller adjusts the rotation speed of the electromagnetic stirrer to ensure that the speed can be adjusted according to the state of the nickel-based corrosion-resistant alloy continuous casting billet. This allows the nickel-based corrosion-resistant alloy liquid to form a uniform grain structure during crystallization, resulting in a final nickel-based corrosion-resistant alloy continuous casting billet used for the fabrication of high-performance nut connectors. The BP neural network is a well-known technology and will not be described further in this embodiment.

[0098] Thus, the final nickel-based corrosion-resistant alloy continuous casting billet was obtained.

[0099] Step S006: High-performance nut connectors are prepared using the final nickel-based corrosion-resistant alloy continuous casting billet.

[0100] The fabrication of high-performance nut connectors mainly involves the following processes:

[0101] Material acquisition: Using the method in step two, the rotation speed of the electromagnetic stirrer was adaptively adjusted to prepare a nickel-based corrosion-resistant alloy continuous casting billet that meets the specifications of the nut connector.

[0102] Cold heading: The final nickel-based corrosion-resistant alloy continuous casting billet is cold-headed and gradually formed into the predetermined shape of a high-performance nut connector through extrusion and stretching.

[0103] Heat treatment: The final nickel-based corrosion-resistant alloy continuous casting billet after cold heading is subjected to heat treatment, including quenching, tempering and other processes, in order to adjust its microstructure and hardness and improve its mechanical properties.

[0104] Turning and threading: The heat-treated nickel-based corrosion-resistant alloy continuous casting billet is turned and threaded to obtain high-performance nut connectors;

[0105] Cleaning and polishing: The high-performance nut connectors are cleaned to remove impurities and oil that may adhere to their surfaces, and then polished to improve the surface finish.

[0106] Quality inspection: Quality inspection of high-performance nut connectors, including inspection of appearance, dimensions, thread accuracy, hardness, etc., to ensure that high-performance nut connectors meet relevant standards and regulations;

[0107] Packaging: High-performance nut connectors that meet quality standards are packaged, usually in boxes or bags, to protect them from damage during transportation and storage.

[0108] Thus, a high-performance nut connector and its manufacturing method have been realized.

[0109] It should be noted that the order of the above embodiments of the present invention is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. Furthermore, the above description focuses on specific embodiments of this specification. Additionally, the processes depicted in the accompanying drawings do not necessarily require a specific or sequential order to achieve the desired results. In some embodiments, multitasking and parallel processing are possible or may be advantageous.

[0110] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0111] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for manufacturing a high-performance nut connector, characterized in that, The method includes the following steps: Raw material preparation: Prepare and mix the raw materials for nickel-based corrosion-resistant alloys according to the specified proportions; Alloy smelting: The raw materials for preparing nickel-based corrosion-resistant alloys are smelted in an electric arc furnace to obtain a nickel-based corrosion-resistant alloy liquid; Preheating and casting: The ladle is preheated to 1200℃; the nickel-based corrosion-resistant alloy liquid is transferred from the electric arc furnace to the preheated ladle, and then cast. The ladle is transported to the rotary table, which carries the ladle to the continuous casting tundish; the rotary table casts the nickel-based corrosion-resistant alloy liquid from the ladle into the continuous casting tundish, and the liquid flows into the crystallizer along the continuous casting tundish. Electromagnetic stirring crystallization: A combined electromagnetic stirrer is installed on the crystallizer to stir the nickel-based corrosion-resistant alloy liquid during the crystallization process to obtain a solid nickel-based corrosion-resistant alloy. Straightening: The straightening equipment of the continuous casting machine bends, stretches or compresses solid nickel-based corrosion-resistant alloys to obtain nickel-based corrosion-resistant alloy billets; Grayscale images of nickel-based corrosion-resistant alloy billets were acquired and binarized to obtain the billet texture normality index of closed contours in the binary images. Hyperspectral images of nickel-based corrosion-resistant alloy billets were acquired, and the alloy texture confidence of linear textures was obtained based on the texture information in the hyperspectral images. Based on the billet texture normality index of all closed contours and the alloy texture confidence of all linear textures, the stirring speed correction coefficient was obtained, the speed of the electromagnetic stirrer was adjusted, and the final nickel-based corrosion-resistant alloy continuous casting billet was obtained by continuous casting. High-performance nut connectors were prepared using the final nickel-based corrosion-resistant alloy continuous casting billet.

2. The method for manufacturing a high-performance nut connector according to claim 1, characterized in that, The raw materials for preparing the nickel-based corrosion-resistant alloy include: carbon, nickel, chromium, molybdenum, copper, titanium, silicon, manganese, and iron.

3. The method for manufacturing a high-performance nut connector according to claim 2, characterized in that, The mass percentages of each component in the raw materials for preparing the nickel-based corrosion-resistant alloy are as follows: Iron 27.80%, Chromium 20.40%, Molybdenum 2.81%, Copper 1.88%, Titanium 2.15%, Silicon 0.23%, Manganese 0.54%, Carbon 0.011%, Balance: Nickel and unavoidable impurities.

4. The method for manufacturing a high-performance nut connector according to claim 1, characterized in that, The alloy is smelted at a temperature of 1500℃.

5. The method for manufacturing a high-performance nut connector according to claim 1, characterized in that, The casting of the nickel-based corrosion-resistant alloy liquid includes a casting temperature range of 1200–1300°C.

6. The method for manufacturing a high-performance nut connector according to claim 1, characterized in that, The acquisition of the slab texture normality index of the closed contour in the binary image includes: Closed contours in a binary image are obtained using a contour tracking algorithm. The Euclidean distance between the pixel with the smallest horizontal coordinate and the pixel with the largest horizontal coordinate on the closed contour is recorded as the horizontal length. The Euclidean distance between the pixel with the smallest vertical coordinate and the pixel with the largest vertical coordinate on the closed contour is recorded as the vertical length. Closed contours with a horizontal length greater than their vertical length are recorded as horizontal closed contours, and vice versa. Each closed contour is used as input to the shape context algorithm, and the shape context feature value of each pixel on each closed contour is output. The average of the shape context feature values ​​of all pixels on each closed contour is recorded as the shape feature value of each closed contour. The absolute value of the difference between the morphological feature values ​​of each closed contour and the other closed contours is recorded as the morphological feature difference between each closed contour and the other closed contours. The average value of the morphological feature differences between each closed contour and the other closed contours is taken as the negative exponent of an exponential function with the natural constant as the base. The calculation result of the exponential function is taken as the contour morphological consistency. The average gray value of all pixels within each closed contour is recorded as the mean within the contour, and the average gray value of all pixels within the smallest bounding rectangle of each closed contour is recorded as the overall mean. The absolute value of the difference between the gray value of each pixel within the closed contour and the mean value within the contour is recorded as the individual local gray value difference. The average value of the individual local gray value differences of all pixels within the closed contour is recorded as the individual local gray value average difference. The absolute value of the difference between the mean value within the contour and the overall mean value is recorded as the overall local gray value difference. The product of the individual local gray value average difference and the overall local gray value difference is recorded as the gray value diversity index. The weights of the longitudinal closed contour and the transverse closed contour are set to 2 and 1 respectively. The sum of the grayscale diversity index of each closed contour and the preset first adjustment parameter is recorded as the adjusted grayscale diversity index. The product of the adjusted grayscale diversity index and the weights is calculated. The ratio of the contour shape consistency to the product is recorded as the billet texture standardization index.

7. The method for manufacturing a high-performance nut connector according to claim 1, characterized in that, The step of obtaining the confidence level of the alloy texture with linear patterns based on texture information in the hyperspectral image includes: In a binary image, edge lines other than closed contours are denoted as linear textures. The average reflectance of all pixels on each linear ridge in each band of the hyperspectral image of the nickel-based corrosion-resistant alloy billet is recorded as the mean reflectance of each linear ridge in each band. The mean reflectance of each linear ridge in all bands is used as the input of the least squares method to fit the band reflectance fitting curve of the output band. Obtain all peak points on the band reflection fitting curve, record the peak point with the highest reflectivity as the optimal reflection band, and record the reflectivity of each pixel in the optimal reflection band as the representative reflectivity of each pixel. Centered on each pixel on each linear texture, a neighborhood window with a preset side length is constructed. The ratio of the representative reflectance of each pixel to that of each pixel in the neighborhood window is recorded as the reflectance ratio. The difference between the value 1 and the reflectance ratio is recorded as the reflectance similarity. The sum of the reflectance similarities of each pixel to all pixels in the neighborhood window is recorded as the neighborhood reflectance consistency of each pixel. The sum of the neighborhood reflectance consistency of all pixels on each linear texture is recorded as the reflectance prominence index of each linear texture. The heterogeneity of the hyperspectral curves for each linear ridge is represented as follows: Among them, Z j Let H represent the heterogeneity of the hyperspectral curve of the j-th linear ridge, where H is the number of linear ridges, and Y is the number of ridges. j,m Let be the minimum number of peak points on the band reflection fitting curves of the j-th and m-th linear ridges. Let be the band length of the b-th peak point on the band reflection fitting curve of the j-th linear ripple. Let be the band length of the b-th peak point on the band reflection fitting curve of the m-th linear ripple; The product of the hyperspectral curve heterogeneity and the reflectance prominence index, plus a preset second adjustment parameter, is recorded as the degree of alloy texture anomaly, and the reciprocal of the degree of alloy texture anomaly is recorded as the alloy texture confidence level.

8. The method for manufacturing a high-performance nut connector according to claim 1, characterized in that, The process of obtaining the stirring speed correction coefficient, adjusting the rotation speed of the electromagnetic stirrer, and continuously casting the final nickel-based corrosion-resistant alloy continuous casting billet includes: The sum of the average of the normality index of the billet texture of all closed contours and the average of the confidence index of the alloy texture of all linear textures is denoted as the health assessment index. Arrange the health assessment indices at all times in ascending order according to the acquisition time to construct a health assessment sequence. Use the health assessment sequence as the input of a BP neural network to output the stirring speed correction coefficient. The stirring speed correction coefficient is used as the input of the PID controller. The PID controller adjusts the speed of the electromagnetic stirrer according to the stirring speed correction coefficient, and the final nickel-based corrosion-resistant alloy continuous casting billet is obtained by continuous casting.

9. The method for manufacturing a high-performance nut connector according to claim 1, characterized in that, The process of preparing high-performance nut connectors using the final nickel-based corrosion-resistant alloy continuous casting billet includes: Cold heading: The final nickel-based corrosion-resistant alloy continuous casting billet is cold-headed; Heat treatment: The cold-headed nickel-based corrosion-resistant alloy continuous casting billet is subjected to heat treatment, including but not limited to quenching and tempering; Turning and threading: The heat-treated nickel-based corrosion-resistant alloy continuous casting billet is turned and threaded to obtain high-performance nut connectors; Cleaning and polishing: Cleaning and polishing high-performance nut connectors; Quality inspection: Quality inspection is performed on high-performance nut connectors, including but not limited to appearance, dimensions, thread accuracy, and hardness; Packaging: High-performance nut connectors that meet quality inspection standards are packaged, including but not limited to boxed or bagged packaging.

10. A high-performance nut connector, characterized in that, The nut connector is manufactured by a high-performance nut connector preparation method according to any one of claims 1-9.

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