Research method for titanium alloy laser additive manufacturing process parameters

Abstract

The invention focuses on optimization of process parameters of titanium alloy, mainly aims at solving the problems of poor interlayer bonding degree, incomplete fusion, more pores and the like caused by titanium alloy additive manufacturing under certain parameters, provides a research method for process parameters of titanium alloy laser additive manufacturing, and relates to the field of laser additive manufacturing. According to the method, parameter optimization logic is determined, and a unique optimization path of titanium alloy additive manufacturing is provided by combining grain morphology, defect distribution and mechanical properties. The analysis method mainly comprises optical microscope metallographic analysis and mechanical property testing, the structure observation precision is improved, and the isotropy of the titanium alloy additive part is evaluated by testing the tensile strength, the yield strength and the ductility. The interlayer bonding problem of titanium alloy additive manufacturing is solved in a targeted mode. The method is suitable for the manufacturing field of aerospace, medical implants and high-corrosion-resistance parts, and the comprehensive performance and isotropy of additive manufacturing components are improved.

Description

Technical Field

[0001] The present invention relates to the field of laser additive manufacturing, and particularly relates to a research method for process parameters of titanium alloy laser additive manufacturing. Background Art

[0002] Titanium alloys are widely used in the fields of aviation, aerospace, ordnance, shipbuilding, petroleum, etc. due to their excellent properties such as high specific strength, strong corrosion resistance, good low-temperature performance, low elastic modulus and low thermal conductivity, and are known as the "rising third metal". With the increasing urgent demand for high-strength and tough large load-bearing components with lightweight, high performance and long life in aerospace vehicles, the performance index requirements for titanium alloys are also increasing day by day. In particular, the efficient preparation of high-temperature titanium alloys has become the current and future research focus. However, traditional preparation processes such as casting, forging and machining have problems such as high preparation cost, low production efficiency and low material utilization rate, and are difficult to meet the preparation requirements of high-performance titanium alloy components.

[0003] Laser additive manufacturing technology uses a high-energy laser beam as an energy source. Based on the "discrete - stacking" principle, a pre-set three-dimensional model is sliced layer by layer according to process requirements to achieve the direct near-net shaping of three-dimensional structural parts, transforming the complex spatial three-dimensional structural parts into simple two-dimensional superposition manufacturing, greatly reducing the manufacturing difficulty and increasing the design flexibility. It has advantages such as moldless machining, customizable personalized complex structures, and near-net shaping of components. However, during the manufacturing process, changes in process parameters will directly affect the forming quality of components. The influence of different process parameters (such as laser power, scanning speed and wire feeding speed, etc.) on the density and mechanical properties of components has a highly coupled and non-linear relationship. Therefore, optimizing the combination of process parameters in the laser additive manufacturing process and improving the density and mechanical properties of the final formed parts have become key technical problems to be solved urgently.

[0004] The existing patent document published on October 27, 2020: CN111829868A, discloses a research method for process parameters of high-throughput metal additive manufacturing. This method quickly analyzes its microstructure and properties through high-throughput variable-parameter printing of specimens, but this method is only applicable to general metal materials and is not applicable to titanium alloy additive manufacturing. For example, it lacks specific analysis means for micro-defects of titanium alloys (such as pores and lack of fusion defects generated during printing). Summary of the Invention

[0005] The present invention focuses on the optimization of process parameters of titanium alloys, mainly aiming at problems such as poor interlayer bonding, many lack of fusion and pores generated during titanium alloy additive manufacturing under certain parameters. Therefore, a research method for process parameters of titanium alloy laser additive manufacturing is proposed to obtain the relationship between additive manufacturing process parameters and component quality, and then optimize to obtain the optimal process parameters to prevent problems such as poor interlayer bonding, lack of fusion and many pores.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] The present invention proposes a research method for process parameters of titanium alloy laser additive manufacturing, including:

[0008] Variable parameter printing: Preset multiple groups of different process parameters and print additive manufacturing specimens on a titanium alloy substrate;

[0009] Microstructure and material analysis: Analyze the microstructure morphology, macroscopic defects, and density of the specimens to obtain the corresponding relationship between each process parameter and microstructure characteristics;

[0010] Mechanical property testing: Prepare tensile specimens along the horizontal, vertical, and 45° angle directions and conduct mechanical property testing to obtain the tensile strength, yield strength, and elongation under different process parameter conditions;

[0011] Process parameter optimization: Based on the results of microstructure analysis and mechanical property testing, determine the influence law of each process parameter on the quality of additive manufacturing and optimize to obtain the best process parameter combination.

[0012] Further, in the above variable parameter printing step, the process parameters selected by the present invention include laser power, overlap spacing, wire feeding speed, and printing speed.

[0013] Further, the above titanium alloy substrate needs to be surface-treated before printing, including: grinding to a bright surface, cleaning with alcohol, and keeping it in an oven at 60°C for 3 hours.

[0014] Further, the above microstructure and material analysis step specifically includes:

[0015] Grind the specimens on SiC sandpaper and perform mechanical polishing using diamond polishing agent;

[0016] Immerse the polished specimens in a solution composed of 1 ml of hydrofluoric acid, 1 ml of nitric acid, and 18 ml of water for 15 seconds, and ultrasonically clean with alcohol for 5 minutes and then dry to obtain the surface required for metallographic observation;

[0017] Use an optical microscope to analyze the metallographic microstructure morphology, precipitate morphology, macroscopic defects, and density of the specimens.

[0018] Further, the above metallographic microstructure morphology analysis includes the ratio of columnar crystals / equiaxed crystals.

[0019] Further, the above macroscopic defects include pores, inclusions, and lack of fusion.

[0020] Further, the above mechanical property testing step specifically includes:

[0021] Cut the specimens along the horizontal direction, vertical direction, and 45° angle direction respectively, and prepare three tensile specimens for each direction;

[0022] Mechanically polish the surface of the specimens using the metallographic preparation process;

[0023] Conduct tensile tests on the polished specimens at a rate of 1.2 mm / min at room temperature to obtain stress-strain curves, and measure the tensile strength, yield strength, and elongation.

[0024] Furthermore, the specific steps for optimizing the above process parameters are as follows:

[0025] Determine the optimization logic of the titanium alloy: expose the grain boundaries and macroscopic defects of the titanium alloy specimens through the etching solution, and establish a correlation model of process parameters - defect type / density - mechanical properties;

[0026] Combined with metallographic structure analysis and density evaluation, clarify the causal relationship of poor melt pool fluidity → increased porosity → decreased density → deteriorated mechanical properties caused by low power, and form a parameter optimization path guided by defect control;

[0027] Selection of anisotropy depth binding parameters: Through tensile tests in the horizontal, vertical, and 45° directions, determine the influence relationship between the longitudinal strength of titanium alloy additive manufacturing and interlayer lack of fusion, so as to obtain that the optimal parameters need to simultaneously meet high strength and low anisotropy;

[0028] Optimal parameter optimization: Determine the optimal process parameters according to the parameter optimization path guided by defect control, the correlation model of process parameters - defect type / density - mechanical properties, and the requirement that the optimal parameters need to simultaneously meet high strength and low anisotropy.

[0029] Furthermore, the above optimal process parameters are: laser power 2400 W, overlap spacing 2.4 mm, wire feeding speed 1.2 m / min, printing speed 12 mm / s.

[0030] Furthermore, the optimal process parameters proposed by the present invention are applicable to different types of titanium alloy materials, including but not limited to TC11, TC4, Ti-6Al-2Zr-1Mo-1V, etc.

[0031] The optimization of process parameters in the research method of a titanium alloy laser additive manufacturing process parameter proposed by the present invention can be implemented by computer software. Therefore, correspondingly, the present invention proposes a computer-readable storage medium, on which a computer program is stored. When the computer program is run by a processor, it is the above-mentioned research method of a titanium alloy laser additive manufacturing process parameter.

[0032] The present invention also provides a computer device, which includes a memory and a processor. A computer program is stored in the memory. When the processor runs the computer program stored in the memory, the processor executes the above research method for process parameters of titanium alloy laser additive manufacturing.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] 1. The research method for process parameters of titanium alloy laser additive manufacturing proposed by the present invention focuses on the optimization of process parameters of titanium alloy. By determining the parameter optimization logic: combining grain morphology, defect distribution and mechanical properties, a unique optimization path for titanium alloy additive manufacturing is proposed. And the innovation in the details of the optimization process: the main analysis methods are optical microscope metallographic analysis and mechanical property testing, which improve the accuracy of tissue observation. And by testing the tensile strength, yield strength and elongation, the isotropy of titanium alloy additive parts is evaluated. It specifically solves the interlayer bonding problem in titanium alloy additive manufacturing.

[0035] Furthermore, the present invention combines multi-directional tensile testing with the control depth of process defects (lack of fusion, pores) and grain morphology in titanium alloy additive manufacturing to form a unique optimization logic.

[0036] Furthermore, compared with the existing patent: CN111829868A, although the high-throughput method proposed by the comparative patent is efficient, it is only applicable to general metal materials; while for the titanium alloy additive manufacturing specimens of the present invention, the risk of interlayer defects is relatively large, and batch printing better meets the material characteristic requirements, which belongs to a targeted technical improvement. And different from the "microscopic mechanical testing" of the comparative patent, the present invention optimizes the target more in line with engineering requirements (such as high isotropy for aerospace components) through macroscopic multi-directional data. And through multi-directional data, the present invention clarifies that the optimal parameters need to simultaneously meet high strength (transverse / 45° direction) and low anisotropy (longitudinal strength close to other directions), while the microscopic testing of the comparative patent cannot evaluate macroscopic isotropy.

[0037] 2. The research method for process parameters of titanium alloy laser additive manufacturing of the present invention can characterize a large number of process parameters in a relatively short time. And when analyzing the relationship between process parameters and manufacturing quality, it can conduct an overall analysis of titanium alloy specimens. By parallel processing multiple process parameters, it efficiently and comprehensively covers the additive manufacturing quality problems under multiple additive manufacturing process parameters, and quickly establishes the corresponding relationship between additive manufacturing process parameters and manufacturing quality, so as to realize the rapid optimization of process parameters and determine the optimal additive manufacturing process parameters.

[0038] The present invention is applicable to the manufacturing fields of aerospace, medical implants and high corrosion-resistant parts to improve the comprehensive performance and isotropy of additive manufacturing components. Brief Description of the Drawings

[0039] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0040] Figure 1 is a schematic flow chart of a research method for process parameters of laser additive manufacturing of titanium alloy proposed by the present invention;

[0041] Figure 2 is the longitudinal section metallographic microstructure of the specimen described in the present invention;

[0042] Figure 3 is the stress-strain curve obtained from the tensile test of Specimen 1 in the present invention along three directions. Among them, Fig. (a) is the stress-strain curve obtained from the tensile test of Specimen 1 along the horizontal direction, Fig. (b) is the stress-strain curve obtained from the tensile test of Specimen 1 along the vertical direction, and Fig. (c) is the stress-strain curve obtained from the tensile test of Specimen 1 along the 45° direction;

[0043] Figure 4 is the stress-strain curve obtained from the tensile test of Specimen 2 in the present invention along three directions. Among them, Fig. (a) is the stress-strain curve obtained from the tensile test of Specimen 2 along the horizontal direction, Fig. (b) is the stress-strain curve obtained from the tensile test of Specimen 2 along the vertical direction, and Fig. (c) is the stress-strain curve obtained from the tensile test of Specimen 2 along the 45° direction;

[0044] Figure 5 is the stress-strain curve obtained from the tensile test of Specimen 3 in the present invention along three directions. Among them, Fig. (a) is the stress-strain curve obtained from the tensile test of Specimen 3 along the horizontal direction, Fig. (b) is the stress-strain curve obtained from the tensile test of Specimen 3 along the vertical direction, and Fig. (c) is the stress-strain curve obtained from the tensile test of Specimen 3 along the 45° direction. Detailed Embodiments

[0045] In the following description, specific details such as specific system structures and technologies are presented for the purpose of illustration rather than limitation, so as to thoroughly understand the embodiments of the present application. However, those skilled in the art should clearly understand that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid unnecessary details from interfering with the description of the present application.

[0046] The following further elaborates on the specific implementation manners of the present invention in conjunction with the accompanying drawings. The following implementation manners will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several changes and improvements can still be made, and these all fall within the protection scope of the present invention.

[0047] Embodiment 1. Refer to Figure 1 To describe this embodiment, this embodiment provides a research method for process parameters of titanium alloy laser additive manufacturing. Through systematic experiments and analyses, the relationship between process parameters and microstructure and mechanical properties is established to optimize the process parameters and improve the comprehensive performance of the final component. This method is as Figure 1 shown and includes the following steps:

[0048] Step S10: Print titanium alloy additive manufacturing specimens under different process parameters, analyze their longitudinal section microstructures, and conduct mechanical property tests to establish the relationship between process parameters and microstructure characteristics and mechanical properties.

[0049] Step S20: Based on the metallographic microstructure analysis results of the specimens, study the effects of different process parameter conditions on microstructure morphology, interlayer bonding quality, and macroscopic defects (such as lack of fusion, pores, segregation, etc.), and establish the corresponding relationship between process parameters and microscopic microstructure characteristics.

[0050] Step S30: Based on the mechanical property test results of the specimens, study the effects of different process parameters on mechanical properties, and establish the corresponding relationship between process parameters and mechanical properties.

[0051] Step S40: Integrate the microstructure analysis and mechanical property test results, determine the influence law of each process parameter on the final forming quality, and obtain the optimal process parameters for titanium alloy laser additive manufacturing in combination with experimental data.

[0052] In some embodiments, the process parameters include but are not limited to laser power, printing speed, and overlap spacing, etc. By adjusting these process parameters, the microscopic microstructure characteristics of the specimens can be controlled, such as the morphology of precipitates, interlayer bonding quality, etc., so as to optimize the mechanical properties and improve the density and isotropy of the additive manufacturing components.

[0053] Embodiment 2. This embodiment specifically describes step S10 in the above Embodiment 1;

[0054] The specific operations of step S10 include the following:

[0055] Step S11: Pretreat the titanium alloy substrate, polish its surface to a bright state to remove the oxide layer, and perform ultrasonic cleaning with alcohol. Subsequently, place the substrate and TC11 alloy wire in an oven at 60 °C and keep warm for 3 hours.

[0056] Step S12: Based on different combinations of laser power, lap spacing, wire feeding speed, and printing speed, conduct additive manufacturing experiments on the titanium alloy substrate to obtain multiple groups of printed specimens.

[0057] Embodiment 3: This embodiment specifically describes step S20 in Embodiment 1 above;

[0058] The tissue analysis in the said step S20 includes the following specific operations:

[0059] Step S21: Mechanically grind the specimen with SiC sandpaper, perform rough grinding and fine grinding in sequence to eliminate the influence of the surface cutting layer; subsequently, perform mechanical polishing with diamond polishing agent to prepare a metallographic specimen that meets the standards.

[0060] Step S22: Immerse the specimen in an etching solution composed of 1 ml of hydrofluoric acid, 1 ml of nitric acid, and 18 ml of water. After etching for 15 seconds, perform ultrasonic cleaning with alcohol for 5 minutes and dry it.

[0061] Step S23: Use an optical microscope (OM) to analyze the microstructure of the specimen, including the morphology of precipitates, macroscopic defects, and density, etc., and establish the relationship between process parameters and microstructure.

[0062] Embodiment 4: This embodiment specifically describes step S30 in Embodiment 1 above;

[0063] The mechanical property test in the said step S30 includes the following specific operations:

[0064] Step S31: Cut three tensile specimens along the horizontal direction, vertical direction, and 45° direction respectively, and perform surface polishing using the standard metallographic preparation process to remove the work-hardened layer and reduce the influence of surface defects on the test.

[0065] Step S32: Use an electronic universal testing machine to perform tensile tests at a loading rate of 1.2 mm / min at room temperature, record the stress-strain curve, measure the tensile strength, yield strength, and elongation at break, and establish a mechanical property database under different process parameters.

[0066] A research method for titanium alloy laser additive manufacturing process parameters proposed in any of the above embodiments can realize the optimization of process parameters during the additive manufacturing process, improve the forming quality, ensure that the printed parts have excellent comprehensive properties, and meet the application requirements in the fields of aerospace, high-end manufacturing, and biomedicine, etc.

[0067] Embodiment 5. This embodiment specifically describes step S40 in Embodiment 1 above;

[0068] Optimization logic for titanium alloy defects:

[0069] Targeted defect analysis: By using an etching solution to expose the grain boundaries and macroscopic defects (pores, inclusions, and lack of fusion) of titanium alloy specimens, a correlation model of process parameters - defect type / density - mechanical properties is established.

[0070] Quantitative control of relative density: Combining metallographic structure analysis (ratio of columnar crystals / equiaxed crystals) and relative density evaluation, clarify the causal relationship of low power leading to poor melt pool fluidity → increased pores → decreased relative density → deteriorated mechanical properties, and form a parameter optimization path guided by defect control.

[0071] Multi-directional mechanical properties and isotropic collaborative optimization:

[0072] Parameter selection with deep binding of anisotropy: Through tensile tests in the horizontal, vertical, and 45° directions, it is found that the longitudinal strength of titanium alloy additive manufacturing is easily affected by lack of fusion between layers. It is proposed that the optimal parameters need to simultaneously meet high strength and low anisotropy (such as the longitudinal tensile strength of Specimen 2 being close to the horizontal and 45° directions).

[0073] According to the parameter optimization path guided by defect control, the correlation model of process parameters - defect type / density - mechanical properties, and the requirement that the optimal parameters need to simultaneously meet high strength and low anisotropy, determine the optimal process parameters.

[0074] Embodiment 6. This embodiment provides an actual operation description of a research method for titanium alloy laser additive manufacturing process parameters proposed in any of the above embodiments;

[0075] 1. Perform variable parameter printing on titanium alloy laser additive manufacturing specimens. In this example, three different sets of process parameters are selected for experiments, and the specific parameters are as follows: Specimen 1: laser power 3600W, overlap spacing 2.4mm, wire feeding speed 1.8m / min, printing speed 10mm / s; Specimen 2: laser power 2400W, overlap spacing 2.4mm, wire feeding speed 1.2m / min, printing speed 12mm / s; Specimen 3: laser power 1440W, overlap spacing 1.7mm, wire feeding speed 0.9m / min, printing speed 5mm / s.

[0076] As Figure 2As shown in the figure, the metallographic structures of the longitudinal sections of the three samples were analyzed. It can be found that the longitudinal section of sample 3 is mainly composed of equiaxed crystals, and there are a large number of pores and unfusion defects inside. The interlayer bonding quality is extremely poor and the sample density is low; the longitudinal section of sample 2 is mainly composed of columnar crystals, with fewer pores and inclusions inside, and no unfusion defects, and the interlayer bonding quality is better; the longitudinal section of sample 1 also contains a large number of columnar crystals, and the number of pores and inclusions inside is basically the same as that of sample 2, but three larger pores can be observed, there are no unfusion defects, and the interlayer bonding quality is better.

[0077] like Figures 3 to 5 As shown, the average tensile strength of the transverse tensile samples of Sample 1 was 1003.66 MPa, the average tensile strength of the longitudinal samples was 873.43 MPa, and the average tensile strength of the samples in the 45° direction was 1011.71 MPa; the average tensile strength of the transverse tensile samples of Sample 2 was 882.63 MPa, the average tensile strength of the longitudinal samples was 923.91 MPa, and the average tensile strength of the samples in the 45° direction was 1023.75 MPa; the average tensile strength of the transverse tensile samples of Sample 3 was 876.20 MPa, the average tensile strength of the longitudinal samples was 870.65 MPa, and the average tensile strength of the samples in the 45° direction was 872.17 MPa. Detailed data of the tensile tests of the three samples are shown in Table 1 below.

[0078] Table 1

[0079]

[0080]

[0081] The results of mechanical property tests show that the tensile strength of sample 3 is the lowest in all directions, which is closely related to the presence of many defects inside it, resulting in its poor mechanical properties. Sample 1 has higher tensile strength in the transverse and 45° directions, but its longitudinal tensile strength is significantly lower than that of sample 2, indicating that its isotropy is poor. Sample 2 has the highest longitudinal tensile strength and the optimal tensile strength in the 45° direction. At the same time, its transverse tensile strength is also high, and its overall mechanical properties are the best. The performance differences in different directions are small, showing good isotropy. Overall, sample 2 has a uniform distribution of mechanical properties while ensuring high strength, making it more suitable for engineering applications of additive manufacturing.

[0082] Combining the results of microstructure analysis and mechanical property tests, the following conclusions can be drawn. Due to the low laser power, the molten pool of Specimen 3 has poor fluidity, resulting in low interlayer bonding quality and more internal defects. Therefore, it is not suitable as the optimal process parameters. Although Specimen 1 has relatively high overall strength, its mechanical properties in the longitudinal direction are low, and there are pores with large sizes, which affect the overall uniformity and reliability. Therefore, the process parameters of Specimen 2 achieve the best mechanical property performance while ensuring the uniformity of the microstructure and good interlayer bonding quality. Finally, its process parameters are determined as the optimal ones.

[0083] The finally determined optimal process parameters are as follows: laser power 2400W, overlap spacing 2.4mm, wire feeding speed 1.2m / min, printing speed 12mm / s. These process parameters can effectively improve the comprehensive performance of additive manufacturing components, fully reflecting their application value in the fields of aerospace, high-end manufacturing, and biomedicine.

[0084] In summary, the research method for the process parameters of a titanium alloy laser additive manufacturing process proposed in this embodiment specifically addresses the interlayer bonding problem in titanium alloy additive manufacturing: in titanium alloy additive manufacturing, mechanical properties are prone to anisotropy due to lack of fusion between layers. When the interlayer bonding degree is poor, its longitudinal strength is significantly lower than that in the other two directions. Through multi-directional tensile tests, the influence of parameters on the interlayer bonding quality is clarified, such as the optimal longitudinal strength of Specimen 2. At the same time, isotropy is optimized by combining microstructure analysis: the difference in longitudinal strength of the columnar crystal-dominated microstructure (Specimens 1 and 2) is found, and it is proposed that parameter optimization needs to balance the grain morphology and interlayer bonding.

[0085] Embodiment 7. The optimization of the process parameters in the research method for the process parameters of a titanium alloy laser additive manufacturing process proposed in the above embodiment can be realized by computer software. Therefore, correspondingly, this embodiment proposes a computer-readable storage medium, on which a computer program is stored. When the computer program is run by a processor, the above-mentioned research method for the process parameters of a titanium alloy laser additive manufacturing process is implemented.

[0086] Embodiment 8. This embodiment proposes a computer device, which includes a memory and a processor. A computer program is stored in the memory. When the processor runs the computer program stored in the memory, the processor executes the above-mentioned research method for the process parameters of a titanium alloy laser additive manufacturing process.

[0087] A computer device provided by this embodiment, the hardware device in this part is a general model and is not shown in the form of a diagram. The system includes a processor and a memory. The processor and the memory can be connected through a bus or other means. The memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs and modules, as well as corresponding program instructions / modules. The processor executes various functional applications and data processing of the processor by running the non-transitory software programs, instructions and modules stored in the memory, so as to implement the research method and steps of the titanium alloy laser additive manufacturing process parameters in the above method embodiments.

[0088] The above are only the embodiments of the present invention and do not limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the scope of the claims of the present invention.

Claims

1. A research method for process parameters of laser additive manufacturing of titanium alloy, characterized in that, Including: Variable parameter printing: Preset multiple groups of different process parameters and print specimens for additive manufacturing on a titanium alloy substrate; Microstructure and material analysis: Analyze the microstructure morphology, macroscopic defects, and density of the specimens to obtain the corresponding relationship between each process parameter and microstructure characteristics; Mechanical property testing: Prepare tensile specimens along the horizontal, vertical, and 45° angle directions and conduct mechanical property testing to obtain the tensile strength, yield strength, and elongation under different process parameter conditions; Process parameter optimization: Based on the results of microstructure analysis and mechanical property testing, determine the influence law of each process parameter on the quality of additive manufacturing and optimize to obtain the best process parameter combination.

2. The research method of process parameters for laser additive manufacturing of titanium alloy according to claim 1, characterized in that, The selected process parameters include laser power, overlap spacing, wire feeding speed, and printing speed; The titanium alloy substrate needs to be surface-treated before printing, including: grinding to a bright surface, cleaning with alcohol, and keeping it in an oven at 60°C for 3 hours.

3. The research method of titanium alloy laser additive manufacturing process parameters according to claim 1, characterized in that, The microstructure and material analysis specifically include: Grind the specimens on SiC sandpaper and perform mechanical polishing using diamond polishing agent; Immerse the polished specimens in a solution composed of 1 ml of hydrofluoric acid, 1 ml of nitric acid, and 18 ml of water for 15 seconds, and ultrasonically clean with alcohol for 5 minutes and then dry to obtain the surface required for metallographic observation; Use an optical microscope to analyze the metallographic microstructure morphology, precipitate morphology, macroscopic defects, and density of the specimens.

4. A research method for titanium alloy laser additive manufacturing process parameters according to claim 3, characterized in that The analysis of metallographic microstructure morphology includes the ratio of columnar crystals / equiaxed crystals; macroscopic defects include pores, inclusions, and lack of fusion.

5. A research method for process parameters of titanium alloy laser additive manufacturing according to claim 1, characterized in that, The mechanical property testing specifically includes: Cut the specimens along the horizontal, vertical, and 45° angle directions respectively, and prepare three tensile specimens in each direction; Perform mechanical polishing on the specimen surface using the metallographic preparation process; Conduct tensile testing on the polished specimens at a rate of 1.2 mm / min at room temperature to obtain the stress-strain curve and measure the tensile strength, yield strength, and elongation.

6. The research method of titanium alloy laser additive manufacturing process parameters according to claim 5, characterized in that The process parameter optimization is specifically as follows: Determine the optimization logic of titanium alloy: Expose the grain boundaries and macroscopic defects of titanium alloy specimens through the etching solution, and establish a correlation model of process parameter - defect type / density - mechanical properties; Combined with metallographic microstructure analysis and density evaluation, clarify the causal relationship of low power leading to poor melt pool fluidity → increased pores → decreased density → deteriorated mechanical properties, and form a parameter optimization path guided by defect control; Selection of anisotropy depth-bound parameters: Through tensile testing in the horizontal, vertical, and 45° directions, determine the influence relationship between the longitudinal strength of titanium alloy additive manufacturing and lack of fusion between layers, so as to obtain that the optimal parameters need to meet both high strength and low anisotropy at the same time; Optimal parameter optimization: According to the parameter optimization path guided by defect control, the correlation model of process parameter - defect type / density - mechanical properties, and the requirement that the optimal parameters need to meet both high strength and low anisotropy at the same time, determine the optimal process parameters.

7. A research method for titanium alloy laser additive manufacturing process parameters according to claim 6, characterized in that, The optimal process parameters are: laser power 2400 W, overlap spacing 2.4 mm, wire feeding speed 1.2 m / min, and printing speed 12 mm / s.

8. A research method for titanium alloy laser additive manufacturing process parameters according to claim 7, characterized in that The optimal process parameters are applicable to different types of titanium alloy materials, including but not limited to TC11, TC4, Ti-6Al-2Zr-1Mo-1V.

9. A computer-readable storage medium, characterized in that, A computer program is stored on the computer-readable storage medium, and when the computer program is run by a processor, it executes a research method for process parameters of titanium alloy laser additive manufacturing described in claim 6.

10. A computer device, characterized in that, The device includes a memory and a processor. A computer program is stored in the memory, and when the processor runs the computer program stored in the memory, the processor executes a research method for process parameters of titanium alloy laser additive manufacturing described in claim 6.

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