A numerical simulation method and device for laser selective melting evolution of a titanium alloy

Abstract

The application relates to the field of laser technology and discloses a numerical simulation method and device for evolution of titanium alloy laser selective melting, which comprises the following steps: obtaining a melting mold, wherein the surface of the melting mold has three groups of parallel long grooves; titanium alloy powder is sequentially scattered into the three groups of parallel long grooves; a laser is started to emit a laser beam at a fixed power and sequentially irradiate the titanium alloy powder in the three groups of long grooves until the titanium alloy powder is melted, the irradiation of the laser beam is stopped, and the titanium alloy powder after melting is allowed to solidify to obtain three groups of solidified titanium alloy; the surface heat of each group of solidified titanium alloy is sequentially measured; the heat distribution function of each group of solidified titanium alloy is constructed according to the surface heat; the heat difference value between the three groups of solidified titanium alloy is calculated according to the heat distribution function of each group of solidified titanium alloy; and the quality of the titanium alloy powder is judged according to the heat difference value. The application can reduce the judgment error of the quality of the titanium alloy after laser selective melting.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of laser technology, and in particular to a numerical simulation method and device for titanium alloy laser selective melting evolution, an electronic device and a computer readable storage medium. BACKGROUND

[0002] Selective laser melting (SLM) uses a laser beam to layer melt metal powder and other materials into a shape, which has important value in manufacturing. Commonly used metal powders include copper, aluminum, etc., but with the performance advantages of titanium alloy, laser selective melting based on titanium alloy has more important application prospects.

[0003] Titanium alloy refers to a variety of alloys made of titanium and other metals. Since titanium is an important structural metal, titanium alloys have the advantages of high strength, good corrosion resistance, and high heat resistance. On the other hand, since titanium alloy is made of titanium and other metals, the heat distribution stability of titanium alloy is an important consideration for the quality of titanium alloy when using laser selective melting.

[0004] Currently, the difference in surface heat of titanium alloy after laser selective melting and solidification is mainly determined by a heat probe to determine the quality of titanium alloy. However, the accuracy of the heat probe is affected by many factors, so there is still a large error in determining the quality of titanium alloy after laser selective melting. SUMMARY

[0005] The present application provides a numerical simulation method and device for titanium alloy laser selective melting evolution and a computer readable storage medium, which mainly aims to reduce the judgment error of the quality of titanium alloy after laser selective melting.

[0006] To achieve the above purpose, the present application provides a numerical simulation method for titanium alloy laser selective melting evolution, comprising:

[0007] Receiving a laser selective melting evolution instruction of titanium alloy, and selecting titanium alloy powder for evolution according to the laser selective melting evolution instruction;

[0008] Obtaining a melting mold, wherein the melting mold is a rectangular solid, the material is stainless steel, and there are three groups of parallel long grooves on the surface of the melting mold;

[0009] After the titanium alloy powder is sequentially scattered into the three groups of parallel long grooves, the laser is started to emit a laser beam at a fixed power, and the titanium alloy powder in the three groups of long grooves is sequentially irradiated until the titanium alloy powder is melted, the irradiation of the laser beam is stopped, and the melted titanium alloy powder is solidified to obtain three groups of solidified titanium alloy.

[0010] sequentially measure the surface heat of each group of solidified titanium alloy, and construct a heat distribution function of each group of solidified titanium alloy according to the surface heat;

[0011] According to the heat distribution function of each group of solidified titanium alloy, the heat difference value between the three groups of solidified titanium alloy is calculated, when the heat difference value is greater than or equal to the heat threshold value, it is judged that the titanium alloy powder is unqualified powder, when the heat difference value is less than the heat threshold value, it is judged that the titanium alloy powder is qualified powder.

[0012] Optionally, the titanium alloy powder is sequentially scattered into the three groups of parallel long grooves, comprising:

[0013] The titanium alloy powder is evenly divided into three parts, and the mass of each part of titanium alloy powder is the same;

[0014] The three parts of titanium alloy powder are bound with the corresponding relationship of the three groups of parallel long grooves to obtain the bound titanium alloy powder;

[0015] The depth value of each group of long grooves is determined, and the bound titanium alloy powder is sequentially scattered into the corresponding long grooves and flattened until the depth of the flattened titanium alloy powder reaches four fifths of the depth value of each group of long grooves, and the operation of scattering the titanium alloy powder into the long grooves is completed.

[0016] Optionally, the laser is started to emit a laser beam at a fixed power, and the titanium alloy powder in the three groups of long grooves is sequentially irradiated until the titanium alloy powder is melted and the irradiation of the laser beam is stopped, comprising:

[0017] According to the depth value of each group of long grooves, the fixed power of the laser beam received by each group of long grooves is sequentially calculated;

[0018] The fixed power of the laser is set, wherein the fixed power has a corresponding relationship with the long grooves;

[0019] Based on the corresponding relationship between the fixed power and the long grooves, the laser emits a laser beam with the same power until all the titanium alloy powder in the long grooves is melted, and the laser stops working.

[0020] Optionally, the fixed power of the laser beam received by each group of long grooves is sequentially calculated according to the depth value of each group of long grooves, comprising:

[0021] The fixed power is calculated by the following formula:

[0022]

[0023] wherein, P i represents the fixed power of the laser beam received by the i-th group of long grooves, h i represents the depth value of the i-th group of long grooves, t irepresents the scanning time of the laser beam in the ith group of long grooves, v i represents the laser scanning speed of the laser beam in the ith group of long grooves, u is the working voltage of the laser.

[0024] Optionally, the surface heat of each group of solidified titanium alloy is measured in sequence, comprising:

[0025] The surface of the solidified titanium alloy directly contacted with air is taken as the solidification surface, and a plane rectangular coordinate system is constructed based on the solidification surface;

[0026] n surface points are selected from the solidification surface, and the coordinates of each surface point are represented by (x j ,y j ), x j represents the horizontal coordinate of the jth surface point, y j represents the vertical coordinate of the jth surface point, and j≤n;

[0027] The real-time heat value of each surface point is measured in sequence, and the surface heat of each surface point is calculated according to the pre-constructed surface heat calculation formula and the real-time heat value.

[0028] Optionally, the n surface points are selected from the solidification surface, comprising:

[0029] The width of the solidification surface is determined, and the corresponding three-quantile line, median line and seven-quantile line are determined;

[0030] According to the equidistance principle of the solidification surface length, a plurality of surface points are selected in the three-quantile line, median line and seven-quantile line, and the number of surface points of each quantile line is .

[0031] Optionally, the surface heat of each surface point is calculated according to the pre-constructed surface heat calculation formula and the real-time heat value, comprising:

[0032] The surface heat of the surface point is calculated according to the following formula:

[0033]

[0034] Wherein, q j represents the surface heat of the jth surface point, α is the energy absorption rate of the titanium alloy powder to the laser beam, P i represents the fixed power of the laser beam received by the ith group of long grooves, ω is the laser radius of the laser beam received by the ith group of long grooves, and S is the thickness of the solidified titanium alloy of the ith group of long grooves.

[0035] Optionally, the heat distribution function of each group of solidified titanium alloy is constructed according to the surface heat, comprising:

[0036] n surface points are summarized as n surface heat, and the n surface heat is projected to the plane rectangular coordinate system according to the coordinates of the corresponding surface points, to obtain n heat coordinates, wherein the heat coordinates are represented by (x j ,y j ,q j ), x j represents the horizontal coordinate of the jth surface point, y j represents the vertical coordinate of the jth surface point, and q j represents the surface heat of the (x j ,y j ) surface point.

[0037] The quantile line division is performed on each heat coordinate according to the tertile line, the median line and the septile line, to obtain a set of tertile heat coordinates, a set of median heat coordinates and a set of septile heat coordinates, wherein the coordinates of each heat coordinate are represented by (x j ,q j ) t , wherein t represents the quantile line, and takes the values of 3, 5 or 7.

[0038] The sets of tertile heat coordinates, median heat coordinates and septile heat coordinates are sequentially fitted to obtain quantile heat distribution functions, wherein the quantile heat distribution functions include tertile heat distribution functions, median heat distribution functions and septile heat distribution functions.

[0039] The tertile heat distribution functions, median heat distribution functions and septile heat distribution functions are summarized to obtain heat distribution functions of each group of solidified titanium alloy.

[0040] Optionally, the heat difference values between the 3 groups of solidified titanium alloy are calculated according to the heat distribution functions of each group of solidified titanium alloy, including:

[0041] According to the quantile line correspondence relationship, the quantile heat distribution functions of each group of solidified titanium alloy are sequentially extracted, to obtain 3 groups of tertile heat distribution functions, 3 groups of median heat distribution functions and 3 groups of septile heat distribution functions.

[0042] It is sequentially determined whether the functions of the 3 groups of tertile heat distribution functions are of the same function type, whether the functions of the 3 groups of median heat distribution functions are of the same function type, and whether the functions of the 3 groups of septile heat distribution functions are of the same function type, wherein the function types include linear function type, quadratic function type, cubic function type, quartic function type, Poisson distribution type, Gaussian distribution type, exponential function type, logarithmic function type, trigonometric function type and constant type.

[0043] If there are groups of quantile heat distribution functions that are not of the same function type, it is determined that the heat difference value is infinite.

[0044] If each sub-quantile heat distribution function is of the same function type, then according to the pairwise calculation principle, the function coefficient difference values between the three sub-quantile heat distribution functions included in each group are calculated, and the average value is taken as the heat difference value.

[0045] To solve the above problems, the present application also provides a numerical simulation device for titanium alloy laser selective melting evolution, the device comprises:

[0046] Evolution instruction initiation module, for receiving the laser selective melting evolution instruction of titanium alloy, selecting the titanium alloy powder for evolution according to the laser selective melting evolution instruction;

[0047] Melting mold acquisition module, for acquiring a melting mold, wherein the melting mold is a three-dimensional rectangle, the material is stainless steel, and there are three groups of parallel long grooves on the surface of the melting mold;

[0048] Powder solidification module, for sequentially spreading the titanium alloy powder into the three groups of parallel long grooves, then starting the laser to emit the laser beam at a fixed power, and sequentially irradiating the titanium alloy powder in the three groups of long grooves until the titanium alloy powder is melted, stopping the irradiation of the laser beam, and waiting for the solidification of the melted titanium alloy powder to obtain three groups of solidified titanium alloy;

[0049] Heat distribution function calculation module, for sequentially measuring the surface heat of each group of solidified titanium alloy, and constructing the heat distribution function of each group of solidified titanium alloy according to the surface heat;

[0050] Powder quality judgment module, for calculating the heat difference value between the three groups of solidified titanium alloy according to the heat distribution function of each group of solidified titanium alloy, judging the titanium alloy powder to be unqualified powder when the heat difference value is greater than or equal to the heat threshold value, and judging the titanium alloy powder to be qualified powder when the heat difference value is less than the heat threshold value.

[0051] To solve the above problems, the present application also provides an electronic device, the electronic device comprises:

[0052] Memory, storing at least one instruction; and

[0053] Processor, executing the instructions stored in the memory to implement the numerical simulation method for titanium alloy laser selective melting evolution described above.

[0054] To solve the above problems, the present application also provides a computer readable storage medium, the computer readable storage medium stores at least one instruction, the at least one instruction is executed by the processor in the electronic device to implement the numerical simulation method for titanium alloy laser selective melting evolution described above.

[0055] The embodiment of the present application is to solve the problems described in the background art, first obtain a melting mold, wherein the melting mold is a three-dimensional rectangle, the material is stainless steel, and there are three groups of parallel long grooves on the surface of the melting mold. It needs to be explained that the main purpose of the three groups of parallel long grooves is to form a contrast experiment for comparing the heat distribution differences between the titanium alloy powders in each group of long grooves, thereby reducing the judgment error of the titanium alloy quality. Further, after the titanium alloy powders are sequentially scattered into the three groups of parallel long grooves, the laser is started to emit a laser beam at a fixed power, and sequentially irradiates the titanium alloy powders in the three groups of long grooves, until the titanium alloy powders are melted, the irradiation of the laser beam is stopped, and the titanium alloy powders after melting are solidified, and three groups of solidified titanium alloy are obtained. Then the surface heat of each group of solidified titanium alloy is measured, and the heat distribution function of each group of solidified titanium alloy is constructed according to the surface heat, wherein the heat distribution function can be obtained by fitting the measured values of multiple groups of surface heat, so the error is smaller compared with a simple heat detector. Finally, according to the heat distribution function of each group of solidified titanium alloy, the heat difference value between the three groups of solidified titanium alloy is calculated, when the heat difference value is greater than or equal to the heat threshold value, the titanium alloy powder is judged as unqualified powder, and when the heat difference value is less than the heat threshold value, the titanium alloy powder is judged as qualified powder. Therefore, the numerical simulation method, device, electronic equipment and computer readable storage medium for titanium alloy laser selective melting evolution provided by the present application mainly aim to reduce the judgment error of the quality of titanium alloy after laser selective melting. BRIEF DESCRIPTION OF DRAWINGS

[0056] Figure 1 The flowchart of the numerical simulation method for titanium alloy laser selective melting evolution provided by an embodiment of the present application is shown in the figure;

[0057] Figure 2 The function module diagram of the numerical simulation device for titanium alloy laser selective melting evolution provided by an embodiment of the present application is shown in the figure;

[0058] Figure 3 The structure diagram of the electronic equipment for realizing the numerical simulation method for titanium alloy laser selective melting evolution provided by an embodiment of the present application is shown in the figure.

[0059] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0060] It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0061] The embodiment of the present application provides a numerical simulation method of titanium alloy laser selective melting evolution. The execution subject of the numerical simulation method of titanium alloy laser selective melting evolution includes but is not limited to at least one of electronic devices capable of being configured to execute the method provided by the embodiment of the present application, such as a server, a terminal and the like. In other words, the numerical simulation method of titanium alloy laser selective melting evolution can be executed by software or hardware installed in a terminal device or a server device, and the software can be a blockchain platform. The server includes but is not limited to a single server, a server cluster, a cloud server or a cloud server cluster and the like.

[0062] Referring to Figure 1 Fig. 1 is a flowchart of the numerical simulation method of titanium alloy laser selective melting evolution provided by an embodiment of the present application. In the embodiment, the numerical simulation method of titanium alloy laser selective melting evolution includes the following steps.

[0063] S1, receiving a laser selective melting evolution instruction of titanium alloy, and selecting titanium alloy powder for evolution according to the laser selective melting evolution instruction.

[0064] It can be understood that the process of laser selective melting is complicated, and it will experience a series of complex physical and chemical phenomena in a short time. In particular, titanium alloy, because titanium alloy is a kind of alloy metal made of titanium and other metals, has poorer stability in high temperature environment, so it is extremely important to test the laser selective melting stability of each type of titanium alloy. In the embodiment of the present application, the evolution instruction is generally initiated by a titanium alloy tester, and the titanium alloy powder is in powder form, which can facilitate laser selective melting and numerical simulation after melting.

[0065] S2, obtaining a melting mold, wherein the melting mold is a three-dimensional rectangle, the material is stainless steel, and there are three groups of parallel long grooves on the surface of the melting mold.

[0066] In the embodiment of the present application, the melting mold is an experimental device for containing titanium alloy powder and realizing laser selective melting. It should be emphasized that the melting mold is a three-dimensional rectangular shape, the length is 2-6 mm, the width is 2-4 mm, the height is 1-3 mm, and there are three groups of parallel long grooves on the top surface of the melting mold. Each group of long grooves can be used to contain titanium alloy powder, so as to realize the laser selective melting experiment.

[0067] S3, after the titanium alloy powder is sequentially scattered into the three groups of parallel long grooves, a laser is started to emit a laser beam at a fixed power, and the titanium alloy powder in the three groups of long grooves is sequentially irradiated, until the titanium alloy powder is melted, the irradiation of the laser beam is stopped, and the solidified titanium alloy is obtained after the melted titanium alloy powder is solidified.

[0068] It can be understood that titanium alloy powder needs to be loaded in each group of parallel long grooves, so that the stability of the solidified titanium alloy is determined by irradiating each group of titanium alloy powder with a laser beam and stopping the irradiation of the laser beam after the titanium alloy powder is melted. In detail, the titanium alloy powder is sequentially scattered into 3 groups of parallel long grooves, including:

[0069] The titanium alloy powder is evenly divided into 3 parts, and each part of the titanium alloy powder has the same mass;

[0070] The 3 parts of titanium alloy powder are bound to the corresponding relationship with the 3 groups of parallel long grooves to obtain the bound titanium alloy powder;

[0071] The depth value of each group of long grooves is determined, and the bound titanium alloy powder is sequentially scattered into the corresponding long grooves and flattened until the depth of the flattened titanium alloy powder reaches four-fifths of the depth value of each group of long grooves, completing the operation of scattering the titanium alloy powder into the long grooves.

[0072] For example, if the depth values of the 3 groups of parallel long grooves are 0.5mm, 0.6mm and 0.7mm respectively, the titanium alloy powder is sequentially scattered into the long grooves of 0.5mm, 0.6mm and 0.7mm and flattened, until the depth of the titanium alloy powder in the first group of long grooves reaches 0.4mm, the depth of the second group of titanium alloy powder reaches 0.48mm and the depth of the third group of titanium alloy powder reaches 0.56mm, completing the operation of scattering the titanium alloy powder into the long grooves.

[0073] It can be understood that after the scattering operation of the titanium alloy powder is completed, the laser beam needs to be started to irradiate the titanium alloy powder, so that the melting and re-solidification of the titanium alloy powder are realized. In detail, the laser is started to emit a laser beam with a fixed power, and the titanium alloy powder in the 3 groups of long grooves is sequentially irradiated until the titanium alloy powder is melted and the irradiation of the laser beam is stopped, including:

[0074] According to the depth value of each group of long grooves, the fixed power of the laser beam received by each group of long grooves is sequentially calculated;

[0075] The fixed power of the laser is set, and the fixed power has a corresponding relationship with the long grooves;

[0076] Based on the corresponding relationship between the fixed power and the long grooves, the laser emits a laser beam with the same power until all the titanium alloy powder in the long grooves is melted, and the laser stops working.

[0077] Exemplarily, the depths of the titanium alloy powders in the three groups of long grooves are 0.5 mm, 0.6 mm and 0.7 mm respectively, and therefore the titanium alloy powders included are also different, being 0.4 mm, 0.48 mm and 0.56 mm respectively. Since the qualities of the titanium alloy powders are different, the laser beam energy corresponding to the quality of the titanium alloy powder needs to be set. In detail, the fixed power of the laser beam received by each group of long grooves is calculated in sequence according to the depth value of each group of long grooves, including:

[0078] The fixed power is calculated by the following formula:

[0079]

[0080] wherein P i represents the fixed power of the laser beam received by the i-th group of long grooves, h i represents the depth value of the i-th group of long grooves, t i represents the scanning time of the laser beam in the i-th group of long grooves, v i represents the laser scanning speed of the laser beam in the i-th group of long grooves, and u is the working voltage of the laser.

[0081] It can be understood that when the laser starts to work, the titanium alloy powders in each group of long grooves can be melted in sequence, and then the titanium alloy powders after melting are solidified to obtain solidified titanium alloy by the embodiment of the present application.

[0082] S4, the surface heat of each group of solidified titanium alloy is measured in sequence, and a heat distribution function of each group of solidified titanium alloy is constructed according to the surface heat.

[0083] It needs to be explained that the heat distribution function needs to be constructed by the embodiment of the present application to explore whether each group of solidified titanium alloy is uniformly heated, so as to determine whether the solidified titanium alloy leads to poor subsequent stability due to uneven heating.

[0084] In detail, the surface heat of each group of solidified titanium alloy is measured in sequence, including:

[0085] The surface of the solidified titanium alloy directly contacted with the air is taken as the solidification surface, and a plane rectangular coordinate system is constructed with the solidification surface;

[0086] n surface points are selected from the solidification surface, and the coordinates of each surface point are represented by (x j , y j ), x j represents the horizontal coordinate of the j-th surface point, y j represents the vertical coordinate of the j-th surface point, and j≤n.

[0087] The real-time heat values of each surface point are measured in sequence, and the surface heat of each surface point is calculated according to a pre-constructed surface heat calculation formula and the real-time heat values.

[0088] Exemplarily, the solidified titanium alloy is contained in each of the three groups of long grooves, and it is conceived that the solidified titanium alloy only has one surface directly contacting the air and other surfaces contacting the surfaces of the long grooves. Therefore, the surface directly contacting the air is taken as the solidification surface, and the heat distribution function is constructed.

[0089] In detail, the selecting of the n surface points from the solidification surface comprises:

[0090] The width of the solidification surface is determined, and the corresponding third quantile line, median quantile line and seventh quantile line are determined;

[0091] In the third quantile line, the median quantile line and the seventh quantile line, a plurality of surface points are selected according to the equidistance principle of the length of the solidification surface, and the number of surface points of each quantile line is .

[0092] Exemplarily, if the length of the solidification surface of the first group of long grooves is 2mm and the width is 1mm, the longitudinal coordinates of the third quantile line, the median quantile line and the seventh quantile line are 0.3mm, 0.5mm and 0.7mm respectively. Therefore, in each quantile line, a plurality of surface points are selected according to every 0.01mm interval. Therefore, according to the length of 2mm, 200 surface points can be selected in each quantile line, and a total of 600 surface points can be selected in the three quantile lines.

[0093] Further, the calculation of the surface heat of each surface point according to the pre-constructed surface heat calculation formula and the real-time heat value comprises:

[0094] The surface heat of the surface point is calculated according to the following formula:

[0095]

[0096] wherein q j represents the surface heat of the jth surface point, a is the energy absorption rate of the titanium alloy powder to the laser beam, P i represents the fixed power of the laser beam received by the ith group of long grooves, ω is the laser radius of the laser beam received by the ith group of long grooves, and S is the thickness of the solidified titanium alloy of the ith group of long grooves.

[0097] As known from the above, the surface heat of all n surface points of each group of solidified titanium alloy can be calculated in sequence. Therefore, further, the heat distribution function of the solidified titanium alloy can be fitted according to the surface heat of the n surface points. In detail, the construction of the heat distribution function of each group of solidified titanium alloy according to the surface heat comprises:

[0098] n surface points are summarized to n surface heat, and the n surface heat is projected to the plane rectangular coordinate system according to the coordinates of the corresponding surface points, to obtain n heat coordinates, wherein the heat coordinates are all represented by (x j ,y j ,q j ), x j represents the horizontal coordinate of the jth surface point, y j represents the vertical coordinate of the jth surface point, and q j represents the surface heat of the (x j ,y j ) surface point;

[0099] Each heat coordinate is subjected to quantile line division according to the third quantile line, the median quantile line and the seventh quantile line, to obtain a third heat coordinate set, a median heat coordinate set and a seventh heat coordinate set, wherein the coordinates of each heat coordinate are represented by (x j ,q j ) t , wherein t represents the quantile line and takes the values of 3, 5 or 7;

[0100] The third heat coordinate set, the median heat coordinate set and the seventh heat coordinate set are sequentially fitted to obtain quantile heat distribution functions, wherein the quantile heat distribution functions include a third heat distribution function, a median heat distribution function and a seventh heat distribution function;

[0101] The third heat distribution function, the median heat distribution function and the seventh heat distribution function are summarized to obtain the heat distribution functions of each group of solidified titanium alloy.

[0102] For example, the above 3 quantile lines select a total of 600 surface points, 200 surface points for each quantile line, and thus there are 200 heat coordinates corresponding to each quantile line. Therefore, the heat distribution function is fitted on each quantile line in the embodiment of the application, and the fitting method can use built-in fitting functions such as linear function and quadratic function, so as to obtain the heat distribution function of each quantile line.

[0103] S5, according to the heat distribution functions of each group of solidified titanium alloy, the heat difference values between the three groups of solidified titanium alloy are calculated, when the heat difference value is greater than or equal to the heat threshold value, the titanium alloy powder is judged as unqualified powder, and when the heat difference value is less than the heat threshold value, the titanium alloy powder is judged as qualified powder.

[0104] In detail, according to the heat distribution functions of each group of solidified titanium alloy, the heat difference values between the three groups of solidified titanium alloy are calculated, including:

[0105] According to the quantile line corresponding relationship, the quantile heat distribution function of each group of solidified titanium alloy is extracted in turn, and 3 groups of three-quantile heat distribution functions, 3 groups of middle-quantile heat distribution functions and 3 groups of seven-quantile heat distribution functions are obtained;

[0106] The functions of the three-quantile heat distribution functions, the functions of the middle-quantile heat distribution functions and the functions of the seven-quantile heat distribution functions are sequentially judged to be of the same function type, wherein the function type includes a linear function type, a quadratic function type, a cubic function type, a quartic function type, a Poisson distribution type, a Gaussian distribution type, an exponential function type, a logarithmic function type, a trigonometric function type and a constant type;

[0107] If there is a group of quantile heat distribution functions that are not of the same function type, the heat difference value is determined to be infinite.

[0108] If each group of quantile heat distribution functions is of the same function type, the function coefficient difference values between the three quantile heat distribution functions included in each group are calculated according to the pairwise calculation principle, and the average value is taken as the heat difference value.

[0109] For example, there are 3 groups of solidified titanium alloys, each group of solidified titanium alloy corresponds to a heat distribution function, and the heat distribution function is composed of quantile heat distribution functions. The quantile heat distribution functions of the embodiment of the present application include three-quantile heat distribution functions, middle-quantile heat distribution functions and seven-quantile heat distribution functions. Therefore, the function coefficient difference values between each three-quantile heat distribution function, the function coefficient difference values between each middle-quantile heat distribution function and the function coefficient difference values between each seven-quantile heat distribution function in the 3 groups of solidified titanium alloys are calculated respectively, and the average value is finally taken as the heat difference value.

[0110] As can be known, the quality of the titanium alloy powder can be judged by the heat difference value and the set heat threshold value.

[0111] To solve the problems in the background art, the embodiment of the present application first acquires a melting mold, wherein the melting mold is a three-dimensional rectangle, the material is stainless steel, and there are three groups of parallel long grooves on the surface of the melting mold. It should be explained that the main purpose of the three groups of parallel long grooves is to form a contrast experiment for comparing the heat distribution differences between the titanium alloy powders in each group of long grooves, so as to reduce the judgment error of the quality of the titanium alloy. Further, after the titanium alloy powders are sequentially scattered into the three groups of parallel long grooves, a laser is started to emit a laser beam at a fixed power, and sequentially irradiates the titanium alloy powders in the three groups of long grooves until the titanium alloy powders are melted, and then the irradiation of the laser beam is stopped, and the solidified titanium alloy powders after melting are waited for, so as to obtain three groups of solidified titanium alloy. Then, the surface heat of each group of solidified titanium alloy is measured, and the heat distribution function of each group of solidified titanium alloy is constructed according to the surface heat. The heat distribution function can be obtained by fitting a plurality of measured values of the surface heat, so the error is smaller compared with a simple heat detector. Finally, according to the heat distribution function of each group of solidified titanium alloy, the heat difference value between the three groups of solidified titanium alloy is calculated. When the heat difference value is greater than or equal to a heat threshold value, it is judged that the titanium alloy powder is unqualified powder. When the heat difference value is less than the heat threshold value, it is judged that the titanium alloy powder is qualified powder. Therefore, the numerical simulation method, device, electronic equipment and computer readable storage medium for titanium alloy laser selective melting evolution provided by the present application mainly aim to reduce the judgment error of the quality of the titanium alloy after laser selective melting.

[0112] As Figure 2 shown is a functional module diagram of a numerical simulation device for titanium alloy laser selective melting evolution provided by an embodiment of the present application.

[0113] The numerical simulation device 100 for titanium alloy laser selective melting evolution can be installed in an electronic equipment. According to the functions to be realized, the numerical simulation device 100 for titanium alloy laser selective melting evolution can include an evolution instruction initiation module 101, a melting mold acquisition module 102, a powder solidification module 103, a heat distribution function calculation module 104 and a powder quality judgment module 105. The modules of the present application can also be referred to as units, which refer to a series of computer program segments that can be executed by an electronic equipment processor and can complete a fixed function, and are stored in the memory of the electronic equipment.

[0114] The evolution instruction initiation module 101 is used to receive a laser selective melting evolution instruction of titanium alloy, and select titanium alloy powder for evolution according to the laser selective melting evolution instruction.

[0115] The melting mold acquisition module 102 is used to acquire a melting mold, wherein the melting mold is a three-dimensional rectangle, the material is stainless steel, and there are three groups of parallel long grooves on the surface of the melting mold.

[0116] The powder solidification module 103 is used for sequentially spreading titanium alloy powder into three groups of parallel long grooves, starting a laser to emit a laser beam at a fixed power, and sequentially irradiating the titanium alloy powder in the three groups of long grooves until the titanium alloy powder is melted, stopping the irradiation of the laser beam, and waiting for the solidification of the melted titanium alloy powder to obtain three groups of solidified titanium alloy;

[0117] The heat distribution function calculation module 104 is used for sequentially measuring the surface heat of each group of solidified titanium alloy, and constructing the heat distribution function of each group of solidified titanium alloy according to the surface heat.

[0118] The powder quality judgment module 105 is used for calculating the heat difference value between the three groups of solidified titanium alloy according to the heat distribution function of each group of solidified titanium alloy, judging that the titanium alloy powder is unqualified powder when the heat difference value is greater than or equal to the heat threshold value, and judging that the titanium alloy powder is qualified powder when the heat difference value is less than the heat threshold value.

[0119] In detail, the modules in the numerical simulation device 100 for titanium alloy laser selective melting evolution in the embodiment of the present application adopt the same technical means as the product supply chain management method based on the block chain in the above Figure 1 , and can produce the same technical effects, which will not be repeated here.

[0120] As shown in Figure 3 , it is a structural schematic diagram of an electronic device for implementing the numerical simulation method of titanium alloy laser selective melting evolution provided by an embodiment of the present application.

[0121] The electronic device 1 can include a processor 10, a memory 11 and a bus 12, and can further include a computer program stored in the memory 11 and executable on the processor 10, such as a numerical simulation method of titanium alloy laser selective melting evolution program.

[0122] The memory 11 includes at least one type of readable storage medium, such as a flash memory, a mobile hard disk, a multimedia card, a card-type memory (e.g., an SD or DX memory, etc.), a magnetic memory, a disk, an optical disk, etc. In some embodiments, the memory 11 can be an internal storage unit of the electronic device 1, such as a mobile hard disk of the electronic device 1. In other embodiments, the memory 11 can also be an external storage device of the electronic device 1, such as a plug-in mobile hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. Further, the memory 11 can include both an internal storage unit and an external storage device of the electronic device 1. The memory 11 can be used to store application software and various data installed in the electronic device 1, such as the code of the numerical simulation method program for evolution of laser selective melting of titanium alloy, and can also be used to temporarily store data that has been output or will be output.

[0123] The processor 10 can be composed of an integrated circuit in some embodiments, such as a single packaged integrated circuit, or a plurality of packaged integrated circuits with the same or different functions, including one or more combinations of a central processing unit (CPU), a microprocessor, a digital processing chip, a graphics processor, and various control chips, etc. The processor 10 is the control unit of the electronic device, which connects various components of the entire electronic device through various interfaces and lines, executes programs or modules stored in the memory 11 (such as the numerical simulation method program for evolution of laser selective melting of titanium alloy, etc.), and calls data stored in the memory 11, to perform various functions and process data of the electronic device 1.

[0124] The bus 12 can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The bus 12 can be divided into an address bus, a data bus, a control bus, etc. The bus 12 is configured to realize the connection and communication between the memory 11 and at least one processor 10, etc.

[0125] Figure 3 Only the electronic device with components is shown, and those skilled in the art can understand that, Figure 3The illustrated structure does not constitute a limitation on the electronic device 1, and can include fewer or more components than illustrated, or combine certain components, or different component arrangements.

[0126] For example, although not shown, the electronic device 1 can also include a power source (such as a battery) to power the various components, and preferably the power source can be logically connected to the at least one processor 10 through a power management device, so that the power management device can implement functions such as charge management, discharge management, and power consumption management. The power source can also include one or more DC or AC power sources, recharging devices, power failure detection circuits, power converters or inverters, power status indicators, and any other components. The electronic device 1 can also include various sensors, Bluetooth modules, Wi-Fi modules, and the like, which are not described here.

[0127] Further, the electronic device 1 can also include a network interface, which can optionally include a wired interface and / or a wireless interface (such as a WI-FI interface, a Bluetooth interface, etc.), and is typically used to establish a communication connection between the electronic device 1 and other electronic devices.

[0128] Optionally, the electronic device 1 can also include a user interface, which can be a display (Display), an input unit (such as a keyboard (Keyboard)), and optionally a standard wired interface, a wireless interface. Optionally, in some embodiments, the display can be an LED display, a liquid crystal display, a touch liquid crystal display, and an OLED (Organic Light-Emitting Diode) touch, etc. The display can also be appropriately referred to as a display screen or a display unit, and is used to display information processed in the electronic device 1 and to display a visualized user interface.

[0129] It should be understood that the embodiments are for illustration only and are not limited in scope by the structure.

[0130] The program of the numerical simulation method for the evolution of laser selective melting of titanium alloy stored in the memory 11 in the electronic device 1 is a combination of multiple instructions, which, when executed in the processor 10, can achieve:

[0131] Receiving a laser selective melting evolution instruction of titanium alloy, and selecting titanium alloy powder for evolution according to the laser selective melting evolution instruction;

[0132] Obtaining a melting mold, wherein the melting mold is a rectangular solid, the material is stainless steel, and there are 3 groups of parallel long grooves on the surface of the melting mold;

[0133] After the titanium alloy powder is sequentially scattered into the three groups of parallel long grooves, the laser is started to emit a laser beam at a fixed power, and the titanium alloy powder in the three groups of long grooves is sequentially irradiated until the titanium alloy powder is melted, the irradiation of the laser beam is stopped, and the titanium alloy powder after melting is allowed to solidify to obtain three groups of solidified titanium alloys;

[0134] The surface heat of each group of solidified titanium alloys is sequentially measured, and a heat distribution function of each group of solidified titanium alloys is constructed according to the surface heat;

[0135] According to the heat distribution function of each group of solidified titanium alloys, a heat difference value between the three groups of solidified titanium alloys is calculated, when the heat difference value is greater than or equal to a heat threshold value, it is judged that the titanium alloy powder is unqualified powder, and when the heat difference value is less than the heat threshold value, it is judged that the titanium alloy powder is qualified powder.

[0136] Specifically, the specific implementation method of the processor 10 to the above instructions can refer to Figures 1 to 3 The description of related steps in the corresponding embodiments will not be repeated here.

[0137] Further, the modules / units integrated in the electronic device 1, if realized in the form of software function units and sold or used as independent products, can be stored in a computer readable storage medium. The computer readable storage medium can be volatile or non-volatile. For example, the computer readable medium can include any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory).

[0138] The application also provides a computer readable storage medium, the readable storage medium stores a computer program, when the computer program is executed by the processor of the electronic device, the computer program can realize:

[0139] Receiving laser selective melting evolution instructions of the titanium alloy, selecting titanium alloy powder for evolution according to the laser selective melting evolution instructions of the titanium alloy;

[0140] Obtaining a melting mold, wherein the melting mold is a three-dimensional rectangle, the material is stainless steel, and there are three groups of parallel long grooves on the surface of the melting mold;

[0141] After the titanium alloy powder is sequentially scattered into the three groups of parallel long grooves, the laser is started to emit a laser beam at a fixed power, and the titanium alloy powder in the three groups of long grooves is sequentially irradiated until the titanium alloy powder is melted, the irradiation of the laser beam is stopped, and the titanium alloy powder after melting is allowed to solidify to obtain three groups of solidified titanium alloys;

[0142] The surface heat of each group of solidified titanium alloy is measured in sequence, and the heat distribution function of each group of solidified titanium alloy is constructed according to the surface heat;

[0143] According to the heat distribution function of each group of solidified titanium alloy, the heat difference value between the three groups of solidified titanium alloy is calculated, when the heat difference value is greater than or equal to the heat threshold value, the titanium alloy powder is judged as unqualified powder, and when the heat difference value is less than the heat threshold value, the titanium alloy powder is judged as qualified powder.

[0144] In several embodiments provided by the present application, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other manners. For example, the described device embodiments are merely schematic. For example, the division of the modules is merely a logical function division. There can be another division manner for the actual implementation.

[0145] The modules illustrated as separated components can or can not be physically separated, and the components illustrated as modules can or can not be physical units. That is, they can be located in one place or distributed on a plurality of network units. Some or all of the modules can be selected according to the actual needs to achieve the purposes of the embodiments of the present application.

[0146] In addition, each functional module in each embodiment of the present application can be integrated in one processing unit, or each unit can exist physically independently, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware, or in the form of hardware plus software function module.

[0147] It is obvious for those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application.

[0148] Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting, and the scope of the present application is defined by the appended claims rather than the above description, and therefore all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application. Any reference signs in the claims should not be regarded as limiting the claims to which they relate.

[0149] The blockchain referred to in the present application is a new application mode of computer technologies such as distributed data storage, peer-to-peer transmission, consensus mechanism and encryption algorithm. The blockchain is essentially a decentralized database, and is a series of data blocks associated using cryptographic methods, each data block containing information of a batch of network transactions, for verifying the validity (anti-fake) of the information and generating the next block. The blockchain can include a blockchain underlying platform, a platform product service layer and an application service layer, etc.

[0150] Furthermore, the word "comprising" does not exclude other elements or steps, and the singular does not exclude the plural. Multiple units or devices referred to in a system claim can also be implemented by one unit or device by means of software or hardware. The word "coupled" is used to denote either a direct connection between units or indirect connection through one or more intermediate units.

[0151] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application but not limit the present application, and although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the technical solutions of the present application.

Claims

1. A method of numerical simulation of laser powder bed fusion evolution of a titanium alloy, characterized in that, The method comprises: receiving laser selective melting evolution instructions of the titanium alloy, and selecting titanium alloy powder for evolution according to the laser selective melting evolution instructions; obtaining a melting mold, wherein the melting mold is a three-dimensional rectangle, the material of the melting mold is stainless steel, and there are three groups of parallel long grooves on the surface of the melting mold; after the titanium alloy powder is sequentially scattered into the three groups of parallel long grooves, a laser is started to emit a laser beam at a fixed power, and the titanium alloy powder in the three groups of long grooves is sequentially irradiated until the titanium alloy powder is melted, the irradiation of the laser beam is stopped, and the titanium alloy powder after melting is allowed to solidify to obtain three groups of solidified titanium alloys; the surface heat of each group of solidified titanium alloys is sequentially measured, and a heat distribution function of each group of solidified titanium alloys is constructed according to the surface heat; according to the heat distribution function of each group of solidified titanium alloys, the heat difference value between the three groups of solidified titanium alloys is calculated, when the heat difference value is greater than or equal to the heat threshold value, it is judged that the titanium alloy powder is unqualified powder, and when the heat difference value is less than the heat threshold value, it is judged that the titanium alloy powder is qualified powder; the heat distribution function of each group of solidified titanium alloys is constructed according to the surface heat, comprising: Summarize the n surface heats from n surface points, and project these n surface heats onto the Cartesian coordinate system according to the coordinates of the corresponding surface points, obtaining n heat coordinates, where each heat coordinate is derived from ( )express, Indicates the first The x-coordinate of a surface point Indicates the first The ordinate of a surface point express( Surface heat at surface points; According to the trichotomous line, the median line and the heptachotomous line, the trichotomous heat coordinate set, the median heat coordinate set and the heptachotomous heat coordinate set are obtained, wherein the coordinate of each heat coordinate is expressed as wherein, denotes the trichotomous line, and the value is 3, 5 or 7; fitting the three heat coordinate sets, the middle heat coordinate set and the seven heat coordinate set in sequence to obtain the quantile heat distribution function, wherein the quantile heat distribution function comprises the three heat distribution function, the middle heat distribution function and the seven heat distribution function; the three heat distribution functions, the middle heat distribution function and the seven heat distribution function are summarized to obtain the heat distribution function of each group of solidified titanium alloys.

2. The numerical simulation method of laser powder bed fusion of a titanium alloy according to claim 1, wherein, the titanium alloy powder is sequentially scattered into the three groups of parallel long grooves, comprising: the titanium alloy powder is evenly divided into three parts, wherein each part of the titanium alloy powder has the same mass; binding the three parts of titanium alloy powder with the three groups of parallel long grooves to obtain the bound titanium alloy powder; determining the depth value of each group of long grooves, and sequentially scattering the bound titanium alloy powder into the corresponding long grooves and flattening until the depth of the flattened titanium alloy powder reaches four fifths of the depth value of each group of long grooves to complete the operation of scattering the titanium alloy powder into the long grooves.

3. The numerical simulation method of laser powder bed fusion evolution of a titanium alloy according to claim 2, wherein, the laser is started to emit a laser beam at a fixed power, and the titanium alloy powder in the three groups of long grooves is sequentially irradiated until the titanium alloy powder is melted, the irradiation of the laser beam is stopped, comprising: according to the depth value of each group of long grooves, the fixed power of the laser beam received by each group of long grooves is calculated in sequence; setting the fixed power of the laser, wherein the fixed power has a corresponding relationship with the long grooves; based on the corresponding relationship between the fixed power and the long grooves, the laser emits a laser beam with the same power until all the titanium alloy powder in the long grooves is melted, and the laser stops working.

4. The numerical simulation method of laser powder bed fusion evolution of a titanium alloy according to claim 3, wherein, according to the depth value of each group of long grooves, the fixed power of the laser beam received by each group of long grooves is calculated in sequence, comprising: the fixed power is calculated by the following formula: ； wherein, represents the fixed power of the laser beam received by the group long groove, represents the fixed power of the laser beam received by the group long groove, represents the depth value of the group long groove, represents the depth value of the group long groove, represents the scanning time of the laser beam in the group long groove, represents the scanning time of the laser beam in the group long groove, represents the laser scanning speed of the laser beam in the group long groove, represents the laser scanning speed of the laser beam in the group long groove, is the working voltage of the laser.

5. The numerical simulation method of laser powder bed fusion evolution of a titanium alloy of claim 4, wherein, the surface heat of each group of solidified titanium alloys is sequentially measured, comprising: the surface of the solidified titanium alloy directly contacted with the air is taken as the solidification surface, and a plane rectangular coordinate system is constructed based on the solidification surface; selecting n surface points from the solidification surface, each surface point having coordinates represented by xi, xi, xi, xi, xi, ; The real-time heat values of each surface point are measured in sequence, and the surface heat of each surface point is calculated according to the pre-constructed surface heat calculation formula and the real-time heat value.

6. The numerical simulation method of laser powder bed fusion evolution of a titanium alloy of claim 5, wherein, The n surface points are selected from the solidification surface, including: The width of the solidification surface is determined, and the corresponding three-quantile line, median-quantile line and seven-quantile line are determined; In the three, middle and seven quantile lines, a plurality of surface points are selected according to the equidistance principle of the solidification surface length, and the number of surface points of each quantile line is .

7. The numerical simulation method of laser powder bed fusion evolution of a titanium alloy of claim 6, wherein, The surface heat of each surface point is calculated according to the pre-constructed surface heat calculation formula and the real-time heat value, including: The surface heat of each surface point is calculated according to the following formula: ； wherein, represents a surface heat of the surface point, is an energy absorption rate of the titanium alloy powder to the laser beam, represents a fixed power of the laser beam received by the long groove of the first group, is a laser radius of the laser beam received by the long groove of the first group, is a thickness of the solidified titanium alloy of the long groove of the first group.

8. The numerical simulation method of laser powder bed fusion evolution of a titanium alloy of claim 1 wherein, The heat difference value between the three groups of solidified titanium alloys is calculated according to the heat distribution function of each group of solidified titanium alloys, including: According to the quantile line corresponding relationship, the quantile heat distribution functions of each group of solidified titanium alloys are extracted in sequence, and three groups of three-quantile heat distribution functions, three groups of median-quantile heat distribution functions and three groups of seven-quantile heat distribution functions are obtained; It is judged in sequence whether the three groups of three-quantile heat distribution functions are of the same function type, whether the three groups of median-quantile heat distribution functions are of the same function type, and whether the three groups of seven-quantile heat distribution functions are of the same function type, wherein the function type includes linear function type, quadratic function type, cubic function type, quartic function type, Poisson distribution type, Gaussian distribution type, exponential function type, logarithmic function type, trigonometric function type and constant type; If there are quantile heat distribution function groups that are not of the same function type, it is determined that the heat difference value is infinite; If each group of quantile heat distribution functions is of the same function type, the function coefficient difference value between the three quantile heat distribution functions included in each group is calculated according to the two-by-two calculation principle, and the average value is taken as the heat difference value.

9. A device for numerical simulation of laser powder bed fusion of a titanium alloy, characterized in that, The device comprises: Evolution instruction initiation module, for receiving laser selective melting evolution instruction of titanium alloy, and selecting titanium alloy powder for evolution according to the laser selective melting evolution instruction; Melting mold acquisition module, for acquiring a melting mold, wherein the melting mold is a three-dimensional rectangle, the material is stainless steel, and there are three groups of parallel long grooves on the surface of the melting mold; Powder solidification module, for sequentially spreading titanium alloy powder into the three groups of parallel long grooves, then starting a laser to emit a laser beam at a fixed power, and sequentially irradiating the titanium alloy powder in the three groups of long grooves until the titanium alloy powder is melted, then stopping the irradiation of the laser beam, and waiting for the solidification of the melted titanium alloy powder to obtain three groups of solidified titanium alloys; Heat distribution function calculation module, for sequentially measuring the surface heat of each group of solidified titanium alloys, and constructing the heat distribution function of each group of solidified titanium alloys according to the surface heat; The heat distribution function of each group of solidified titanium alloys is constructed according to the surface heat, including: Summarize the n surface heats from n surface points, and project these n surface heats onto the Cartesian coordinate system according to the coordinates of the corresponding surface points, obtaining n heat coordinates, where each heat coordinate is derived from ( )express, Indicates the first The x-coordinate of a surface point Indicates the first The ordinate of a surface point express( Surface heat at surface points; According to the trichotomous line, the median line and the heptachotomous line, the trichotomous heat coordinate set, the median heat coordinate set and the heptachotomous heat coordinate set are obtained, wherein the coordinate of each heat coordinate is expressed as wherein, denotes the trichotomous line, and the value is 3, 5 or 7; The three-quantile heat coordinate set, the median-quantile heat coordinate set and the seven-quantile heat coordinate set are sequentially fitted to obtain quantile heat distribution functions, wherein the quantile heat distribution functions include three-quantile heat distribution functions, median-quantile heat distribution functions and seven-quantile heat distribution functions; The three-quantile heat distribution functions, the median-quantile heat distribution functions and the seven-quantile heat distribution functions are summarized to obtain the heat distribution function of each group of solidified titanium alloys; The powder quality judgment module is configured to calculate a heat difference value between the three groups of solidified titanium alloy according to the heat distribution function of each group of solidified titanium alloy, and when the heat difference value is greater than or equal to a heat threshold value, judge that the titanium alloy powder is unqualified powder, and when the heat difference value is less than the heat threshold value, judge that the titanium alloy powder is qualified powder.

Images