CN109128168B - Method for planning synchronous powder feeding additive manufacturing process based on structural characteristics - Google Patents

Abstract

The invention provides a method for planning a synchronous powder feeding additive manufacturing process based on structural characteristics, and relates to the technical field of additive manufacturing. The method comprises the steps of firstly, dividing titanium alloy structural parts into beams, frames, joints, wall plates and ribs, and designing a part digital model into a process digital model according to the characteristics of a synchronous powder feeding additive manufacturing process; then, carrying out layered slicing processing on the process digital analogy, carrying out region division on each layer of sheet data according to structural characteristics, and dividing each type of titanium alloy structural part into a plane type, a cross type, an I shape, a straight type, a T shape and an L shape; and finally, optimizing the structural characteristic synchronous powder feeding additive manufacturing process and the process parameters to form a database, and carrying out research on the subsequent additive manufacturing process design of specific parts to efficiently finish the additive manufacturing process design with high quality. The method for planning the synchronous powder feeding additive manufacturing process based on the structural characteristics simplifies the design difficulty of the additive manufacturing process, shortens the process design period and improves the process arrangement efficiency.

Description

Method for planning synchronous powder feeding additive manufacturing process based on structural characteristics

Technical Field

The invention relates to the technical field of additive manufacturing, in particular to a method for planning a synchronous powder feeding additive manufacturing process based on structural characteristics.

Background

Laser Additive Manufacturing (LAM is commonly known as 3D printing) is an integrated technology which takes material preparation and high-performance part forming into consideration, wherein alloy powder is used as a raw material, and high-power Laser in-situ metallurgical melting and rapid solidification and layer-by-layer accumulation are performed. The principle is that a three-dimensional model of a part is designed by using three-dimensional software of a computer, then the model is subjected to certain layering slicing processing, the three-dimensional model is discretized into a series of two-dimensional layers, and then the three-dimensional model of the computer is directly converted into a solid part by using a laser layer-by-layer scanning and superposition forming mode to add powder materials. From the manufacturing of complex-shaped parts, it has incomparable advantages compared with the traditional manufacturing technology: the laser additive manufacturing technology can realize near-net forming, save materials, does not need a die or a special clamp, has short production period and high efficiency, and the manufactured parts have excellent mechanical properties. And therefore are mainly applied to the rapid manufacturing of structural and functional metal parts in the aerospace field.

According to different manufacturing processes, the laser additive manufacturing technology can be divided into three types, namely synchronous feeding, preset powder paving and combination of synchronous feeding and preset powder paving. Wherein, the synchronous feeding can be divided into two processes of synchronous powder feeding and synchronous wire feeding. The synchronous powder feeding is that the airborne powder feeder is utilized to directly convey laser deposition powder into a laser molten pool, and a deposition layer is formed along with the movement of the molten pool on the surface of a workpiece. Two methods for realizing synchronous powder feeding are provided, one is lateral powder feeding, and the other is coaxial powder feeding. Compared with a preset powder feeding mode, the synchronous powder feeding can well realize gas protection, so that the performance of the cladding powder is not influenced by elements such as oxygen, nitrogen and the like in the air, and the excellent mechanical property of a deposition layer is realized.

The metal powder feeding laser additive manufacturing technology is laser cladding deposition fundamentally, and metal powder is synchronously conveyed into a dynamic molten pool formed by laser beam irradiation by using a coaxial feeding nozzle in the processing process to complete melting, solidification and forming of the metal powder. The technology is mainly applied to the rapid preparation of complex metal parts and the surface modification and repair of workpieces. On the other hand, for parts with complicated structures, the traditional manufacturing methods such as casting, forging and the like are difficult to produce, and even if the manufacturing methods are available, the problems of long production period, high cost, difficult improvement of production capacity and the like exist. By utilizing the metal powder feeding additive manufacturing technology, the manufacturing period can be greatly shortened, the cost is reduced, and the mass production is easy; on the other hand, for some large parts with local damage, especially large titanium alloy parts in aviation and aerospace, if the large titanium alloy parts are produced again, the production cost is greatly increased, the production period is prolonged, and the production task is difficult to be ensured to be completed on time. By utilizing the metal powder feeding laser additive manufacturing technology, only the damaged part needs to be locally repaired, the repairing time is short, and the performance of the repaired part completely meets the production standard, so that the production cost can be greatly reduced, and the loss can be recovered.

The existing planning method for the synchronous powder feeding additive manufacturing process mainly has the following problems:

(1) the design of the additive manufacturing process depends on the personal experience of a designer

In view of the fact that the existing synchronous powder feeding additive manufacturing technology is immature in production equipment and is single-production or small-batch production, the synchronous powder feeding additive manufacturing technology depends on experience of technologists to set relevant process parameters and adjust the relevant equipment, different technologists have different design experiences, the experience of the technologists needs time accumulation, personal experience does not have a specific measurement index, the management is not easy, the requirement on the qualification of the technologists is high, manual control does not have a unified standard, the quality is unstable, certain follow-up processing needs to be carried out in order to meet the requirement, the efficiency is low, and the risk is high.

(2) Different parts increase material manufacturing process designs can not be used for reference, each part needs to design the increase material manufacturing process design in detail, and the workload is huge

The parts of different types are made of different materials, even if the materials are the same, the processes of the parts with different structural configurations and sizes are different, the quality of the formed parts is different, the conditions of the formed parts of the product are different, the process window is narrow, the parameters are difficult to set, in addition, the different process personnel of each type of parts are different in design process, so that the internal organization structures of the parts are different, reference cannot be made, and the process of each step cannot be carried over.

(3) High quality risk

Deformation and cracks in the additive manufacturing process are caused by internal stress generated in the forming process, the internal stress is generated due to overlarge temperature gradient, different process personnel and different process parameters set by different parts, the surface state of a workpiece is poor due to fluctuation of a certain process parameter in the design process of the powder feeding laser additive manufacturing process, and if the workpiece cannot be repaired in time, the process cannot be further carried out, and even the workpiece is scrapped. The process stability is poor due to the fact that spheroidization and the like may occur in the process, the processing procedures are sometimes increased, the quality consistency is poor, the unstable phenomenon in the additive manufacturing process taking powder as a material is more serious, risks exist, and evaluation cannot be carried out.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a method for planning a synchronous powder feeding additive manufacturing process based on structural characteristics, aiming at the defects of the prior art, so that the design efficiency of the additive manufacturing process is improved, the design knowledge is inherited, and the quality of a finished piece is improved.

A method for planning a synchronous powder feeding additive manufacturing process based on structural characteristics comprises the following steps:

step 1, designing a process digital model: the titanium alloy structural part is divided into beams, frames, joints, wall plates and ribs, and a part digital model is designed into a process digital model according to the characteristics of a synchronous powder feeding additive manufacturing process;

according to the characteristics of the synchronous powder feeding additive manufacturing process, removing some fine structures of a specific part model, carrying out model regularization treatment, adding a process support, designing a substrate, selecting an additive manufacturing deposition growth direction, and designing into the additive manufacturing process model;

step 1.1, removing a fine structure: removing fine structures such as micro holes, grooves and small bosses of part data according to an additive manufacturing process, increasing the wall thickness of the part, and reserving nondestructive testing and machining allowance;

step 1.2, carrying out regularization treatment on the model according to the characteristics of the shape and the material characteristics of the part;

step 1.3, designing and selecting an additive growth direction and adding a process support: according to the sizes of the projection sectional areas of the part space X, Y, Z in three directions, the optimal direction of the minimum sectional area is used as the growth direction of additive manufacturing deposition, and the growth direction is supported by cantilever addition process;

step 2, characteristic partitioning: carrying out layered slicing processing on the process digital analogy, carrying out region division on each layer of sheet data according to structural characteristics, and dividing each type of titanium alloy structural part into a plane type, a cross type, an I shape, a straight type, a T shape and an L shape;

step 2.1, carrying out layered slicing treatment on the process digital model: for parts with simple shapes, carrying out layered slicing according to the given layer thickness according to the design and the selected growth direction; selecting a main growth direction for parts with complex shapes, dividing a cantilever or other parts which are not suitable for one-time additive manufacturing, slicing the parts in a layered mode according to the main growth direction, and then rotating a digital model to slice the parts in a layered mode according to the divided parts in a secondary growth direction to obtain a group of slice data;

step 2.2, partitioning the slice data according to the structural characteristics: each layer sheet is divided according to regions to obtain a plurality of region combinations with simple configuration characteristics, a large number of parts are sliced in layers and the regions are divided, and the characteristics are summarized to obtain six structural configurations of a plane type, a cross type, an I type, a straight type, a T type and an L type;

step 2.3, obtaining the sizes of a plane type, a cross type, an I shape, a straight shape, a T shape and an L shape after characteristic partitioning, wherein the specific sizes of the length and the width of the components in the characteristics are adjusted and optimized by combining the size of a process digital model corresponding to each layer of slice data and a synchronous powder feeding additive manufacturing process;

step 3, designing an additive manufacturing process: optimizing the structural characteristic synchronous powder feeding additive manufacturing process and the process parameters to form a database, and carrying out research on the design of the subsequent additive manufacturing process of specific parts to efficiently finish the design of the additive manufacturing process with high quality;

3.1, according to the form, the size and the laser power of equipment, conducting theoretical analysis and experimental verification on typical structural characteristics, namely a planar type, a cross type, an I shape, a straight type, a T shape and an L shape, of the additive manufacturing process summarized from mass parts, finally solidifying the process and working steps, optimizing process parameters, summarizing parameter sets of laser power P, scanning speed V, powder feeding speed F, scanning interval I and layering thickness delta h of each structural configuration, and establishing an additive manufacturing process database based on characteristic partitioning;

and 3.2, for a new part needing additive manufacturing, firstly, carrying out layered slicing on the process digital model, partitioning according to structural features, then calling parameters from a process parameter library, and finishing additive manufacturing process design with high efficiency and high quality.

Adopt the produced beneficial effect of above-mentioned technical scheme to lie in: according to the method for planning the synchronous powder feeding additive manufacturing process based on the structural characteristics, the layer sheet data are partitioned and used according to the characteristics, so that the reliable inheritance of additive manufacturing process knowledge is realized, the design difficulty of the additive manufacturing process is reduced, the process design efficiency is greatly improved, the deformation and cracking of parts in the additive manufacturing process are reduced, and the precision and the production efficiency are improved; the dependence on the experience of people is reduced, the errors caused by people are reduced, and the automation and the intellectualization are favorably realized; the difficulty of the additive manufacturing process design is simplified, the period of the process design is shortened, and the efficiency of process arrangement is improved.

Drawings

Fig. 1 is a flowchart of a method for planning a synchronous powder feeding additive manufacturing process based on structural features according to an embodiment of the present invention;

fig. 2 is a schematic diagram illustrating classification of titanium alloy structural members of an aircraft according to an embodiment of the present invention, wherein (a) is a beam type, (b) is a frame type, (c) is a joint type, (d) is a wall plate type, and (e) is a rib type;

FIG. 3 is a schematic view of structural feature classification of an aircraft titanium alloy part according to an embodiment of the present invention, wherein (a) is a surface, (b) is cross-shaped, (c) is I-shaped, (d) is straight, (e) is T-shaped, and (f) is L-shaped;

FIG. 4 is a schematic view of an S-beam provided by an embodiment of the present invention;

FIG. 5 is a schematic layered diagram of layers 1 to 29 of an S-shaped beam according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of layers 30-58 of an S-beam according to an embodiment of the present invention;

FIG. 7 is a schematic diagram of a skeletal structure provided by an embodiment of the present invention;

FIG. 8 is a schematic diagram of layers 1-15 of a skeletal structure according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of layers 16-203 of a framework structure according to an embodiment of the present invention;

FIG. 10 is a block diagram of an embodiment of the present invention;

FIG. 11 is a schematic diagram of layers 1 to 3 of a frame structure according to an embodiment of the present invention;

FIG. 12 is a schematic diagram of layers 4-11 of a frame structure according to an embodiment of the present invention;

FIG. 13 is a schematic view of a vertical tail beam structure provided in accordance with an embodiment of the present invention;

FIG. 14 is a schematic illustration of layers 1 through 18 of a vertical trailing beam structure according to an embodiment of the present invention;

fig. 15 is a schematic layering diagram of 19 th layer to 74 th layer of a vertical tail beam structure provided by an embodiment of the invention.

Detailed Description

The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

In this embodiment, an aircraft titanium alloy structural member is taken as an example, and additive manufacturing is performed by using the method for planning the synchronous powder feeding additive manufacturing process based on the structural characteristics of the invention.

A method for planning a synchronous powder feeding additive manufacturing process based on structural characteristics is shown in FIG. 1 and comprises the following steps:

step 1, designing a process digital model: the titanium alloy structural part is divided into beams, frames, joints, wall plates and ribs, and a part digital model is designed into a process digital model according to the characteristics of a synchronous powder feeding additive manufacturing process;

in this example, the titanium alloy structural members of the aircraft are classified as shown in fig. 2.

According to the characteristics of the synchronous powder feeding additive manufacturing process, removing some fine structures of a specific part model, carrying out model regularization treatment, adding a process support, designing a substrate, selecting an additive manufacturing deposition growth direction, and designing into the additive manufacturing process model;

step 1.1, removing a fine structure: removing fine structures such as micro holes, grooves and small bosses of part data according to an additive manufacturing process, increasing the wall thickness of the part, and reserving nondestructive testing and machining allowance;

step 1.2, carrying out regularization treatment on the model according to the characteristics of the shape and the material characteristics of the part, such as increasing transition fillets at the position with sudden change of size, designing a sharp corner into a rectangle and increasing the part with smaller wall thickness;

step 1.3, designing and selecting an additive growth direction and adding a process support: according to the sizes of the projection sectional areas of the part space X, Y, Z in three directions, the optimal direction of the minimum sectional area is used as the growth direction of additive manufacturing deposition, and the growth direction is supported by cantilever addition process;

step 2, characteristic partitioning: carrying out layered slicing processing on the process digital analogy, carrying out region division on each layer of sheet data according to structural characteristics, and dividing each type of titanium alloy structural part into a plane type, a cross type, an I shape, a straight type, a T shape and an L shape;

step 2.1, carrying out layered slicing treatment on the process digital model: for parts with simple shapes, the parts are sliced in layers in the given layer thickness according to the design and the selected growth direction. For parts with complex shapes, the main growth direction is selected, the cantilever or other parts which are not suitable for one-time additive manufacturing are divided, the parts are sliced in layers according to the main growth direction, and then the parts are sliced in layers according to the secondary growth direction by rotating a digifax. This results in a set of slice data.

Step 2.2, partitioning the slice data according to the structural characteristics: the shapes and structures of the parts are different, the shapes of the laminas after layered slicing are also various, but the laminas are analyzed and then continuously divided, namely the laminas are partitioned according to the structural characteristics, each lamina can be divided according to the region to obtain region combinations with simple configuration characteristics, a large number of parts are layered sliced and region divided, and the characteristics are summarized to obtain six structural configurations of a plane type, a cross type, an I shape, a straight type, a T shape and an L shape shown in figure 3.

In this embodiment, the S-beam process models shown in fig. 4 are layered, and are totally 58 layers, and from the comparison of the layered data analysis, the shapes of 1 layer to 29 layers are similar as shown in fig. 5, and the shapes of 30 layers to 58 layers are similar as shown in fig. 6. Analysis of fig. 5 shows that the additive manufacturing laser scan is a scan of a larger plane, which can be divided into 6 regions, such as R1, R2, r.a. R6, shown in fig. 5. As can be seen from the analysis of fig. 6, the analysis can be divided into 25 regions according to characteristics, and the generalized analysis has four structural characteristics: l-shaped, I-shaped, straight-line and surface-shaped structures; wherein R1 and R16 are L-shaped structures, R4, R5, R7, R9, R10, R11, R13, R14, R15, R21, R24 and R25 are I-shaped structures, R2, R6, R8, R12, R17, R18, R19, R20, R22 and R23 are I-shaped structures, and R3 is a face-shaped structure.

The digital model of the bond head structure shown in fig. 7 is layered, and the structure from layer 1 to layer 15 is shown in fig. 8, which can be divided into 8 zones according to the structural characteristics. The structure from 16 to 203 layers is shown in fig. 9, and can be divided according to structural characteristics, and the characteristics after division mainly comprise 3 types such as an L shape, a T shape, a cross shape and the like. Wherein R1, R11, R12 and R18 are L-shaped structures, R2, R3, R4, R5, R6, R7, R8, R9, R10, R13, R14 and R19 are T-shaped structures, and R15, R16, R17 and R20 are cross-shaped structures.

The force bearing frame structure digital model shown in fig. 10 is processed in a layering way, the shape from 1 layer to 3 layers is shown in fig. 11, the shape can be divided into 8 blocks according to the structural characteristics, the shape from 4 layers to 11 layers is shown in fig. 12, the shape can be divided into 36 zones according to the structural characteristics, 36 zones are provided in total, R and R are planar structures, R are I-shaped structures, R are I-shaped structures, and R, R and R are T-shaped structures.

And 2.3, after the characteristic is partitioned, obtaining the sizes of a plane type, a cross type, an I shape, a straight shape, a T shape and an L shape, such as the length and the width of the whole characteristic, and the specific sizes of the length and the width of a component in the characteristic are adjusted and optimized by combining the size of a process digital model corresponding to each layer of the slice data and a synchronous powder feeding additive manufacturing process.

The parts have different complexity and sizes, for example, the S beam, the binding joint, the bearing frame and other parts have different complexity ranges, the size is from dozens of millimeters to several meters, and only a plurality of simple structural characteristics exist after the parts pass through the characteristic partition. The rapid and high-quality design of the additive manufacturing process of tens of thousands of parts at noon with complex structures and different sizes can be completed only by solidifying and optimizing the additive manufacturing process of the structural characteristics. The method comprises the steps of analyzing the characteristics of different types of parts to obtain 6 types of planes, crosses, I-shaped parts, T-shaped parts and L-shaped parts, wherein the planes are similar to the I-shaped parts, but web plates and rafters in the titanium composite structural part are main structural characteristics, and additive manufacturing processes with different scales are different, namely the planes are divided into 2 types according to the structural characteristics and the additive manufacturing process characteristics. Similarly, the I-shape and T-shape are divided into 2 different types.

Step 3, designing an additive manufacturing process: and optimizing the structural characteristic synchronous powder feeding additive manufacturing process and the process parameters to form a database, and then researching the additive manufacturing process design of the subsequent specific parts, thereby efficiently finishing the additive manufacturing process design with high quality.

3.1, according to the form, the size and the laser power of equipment, conducting theoretical analysis and experimental verification on typical structural characteristics, namely a planar type, a cross type, an I shape, a straight type, a T shape and an L shape, of the additive manufacturing process summarized from mass parts, finally solidifying the process and working steps, optimizing process parameters, summarizing parameter sets of laser power P, scanning speed V, powder feeding speed F, scanning interval I and layering thickness delta h of each structural configuration, and establishing an additive manufacturing process database based on characteristic partitioning;

in this embodiment, the established process database is shown in table 1:

TABLE 1 Process database

Structural features

mode/S

power/P

Scanning rate/V

Powder feed rate/F

Scanning pitch/I

Layer thickness/. DELTA.h

Straight line type

Syi

Pyi

Vyi

Fyi

Iyi

Δhyi

Cross type

Ssi

Psi

Vsi

Fsi

Isi

Δhsi

T-shaped

Sti

Pti

Vti

Fti

Iti

Δhti

L-shaped character

Sli

Pli

Vli

Fli

Ili

Δhli

I-shaped

Sgi

Pgi

Vgi

Fgi

Igi

Δhgi

Noodle

Smi

Pmi

Vmi

Fmi

Imi

Δhmi

In the table, yi represents the ith straight-line structural feature of the part, si represents the ith cross structural feature of the part, ti represents the ith T-line structural feature of the part, li represents the ith L-line structural feature of the part, gi represents the ith I-line structural feature of the part, and mi represents the ith surface structural feature of the part.

And 3.2, for a new part needing additive manufacturing, firstly, carrying out layered slicing on the process digital model, partitioning according to structural features, then calling parameters from a process parameter library, and finishing additive manufacturing process design with high efficiency and high quality.

In this embodiment, for the vertical tail beam shown in fig. 13, the structure from layer 1 to layer 18 is shown in fig. 14, and may be simply partitioned, and the structure from layer 19 to layer 74 is shown in fig. 15, and may be partitioned into four structures, i.e., L-shaped, in-line-shaped, i-shaped, and plane, and when "L-shaped" is processed, the P of the process database is called_l1、V_l1、F_l1、I_l1、Δh_l1Working L₁Call P_l2、V_l2、F_l2、I_l2、Δh_l2Working L₂Calling P when processing "font_yi、V_yi、F_yi、I_yi、Δh_yiSeparately working Y_iI from 1 to 12, calling P when processing "I-shape_gi、V_gi、F_gi、I_gi、Δh_giWorking out G separately_iI from 1 to 6, calling P when processing "surface_mi、V_mi、F_mi、I_mi、Δh_miWorking M_i。

The heat accumulation is generated during the part processing, and in order to weaken the heat accumulation and prevent the part from deforming, the part is processed in a blocking mode during the processing, the optimum processing sequence is found, and the part is processed in different areas, so that the influence on the same layer can be weakened, and the influence on the next layer can be weakened. As shown in fig. 14, each of the 1 to 18 layers is divided into 6 blocks according to the presetProcessing sequence, processing track, processing distance, scheduling technological parameter P of' surface_mi、V_mi、F_mi、I_mi、Δh_miMi, 1 layer to 18 layers are processed similarly.

When processing 19 to 74 layers, the processing order, processing path, and processing distance are set in advance. Because each layer is simultaneously provided with an L shape, a straight shape, an I shape and a surface, according to the principle of processing by regions, the process parameter P of the surface is firstly called_m1、V_m1、F_m1、I_m1、Δh_m1Working M₁. Then the technological parameter P of the straight line shape is called_y1、V_y1、F_y1、I_yi、Δh_y1Working Y₁Then calling the process parameter P of the straight type_y2、V_y2、F_y2、I_y2、Δh_y2Working Y₂Calling the process parameter P of the straight line_y3、V_y3、F_y3、I_y3、Δh_y3Working Y₃Then, the process parameter P of the 'I shape' is called_g1、V_g1、F_g1、I_g1、Δh_g1Processing G₁Calling the process parameter P of the straight line_y4、V_y4、F_y4、I_y4、Δh_y4Working Y₄Calling the process parameter P of the straight line_y5、V_y5、F_y5、I_y5、Δh_y5Working Y₅Calling the process parameter P of the straight line_y6、V_y6、F_y6、I_y6、Δh_y6Working Y₆Calling the technological parameter P of' I shape_g2、V_g2、F_g2、I_g2、Δh_g2Processing G₂Calling the process parameter P of the straight line_y7、V_y7、F_y7、I_y7、Δh_y7Working Y₇Calling the technological parameter P of' I shape_g3、V_g3、F_g3、I_g3、Δh_g3Processing G₃Calling the process parameter P of the straight line_y8、V_y8、F_y8、I_y8、Δh_y8Working Y₈Calling the technological parameter P of' I shape_g4、V_g4、F_g4、I_g4、Δh_g4Processing G₄Calling the process parameter P of "L type_l1、V_l1、F_l1、I_l1、Δh_l1Working L₁Calling the process parameter P of the straight line_y9、V_y9、F_y9、I_y9、Δh_y9Working Y₉Calling the process parameter P of the straight line_y10、V_y10、F_y10、I_y10、Δh_y10Working Y₁₀Calling the process parameter P of the straight line_y11、V_y11、F_y11、I_y11、Δh_y11Working Y₁₁Calling the technological parameter P of' I shape_g5、V_g5、F_g5、I_g5、Δh_g5Processing G₅Calling the process parameter P of "L type_l2、V_l2、F_l2、I_l2、Δh_l2Working L₂Calling the process parameter P of the straight line_y12、V_y12、F_y12、I_y12、Δh_y12Working Y₁₂Layers 19 to 74 are the same.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit of the corresponding technical solutions and scope of the present invention as defined in the appended claims.

Claims (3)

1. A method for planning a synchronous powder feeding additive manufacturing process based on structural characteristics is characterized by comprising the following steps: the method comprises the following steps:

step 1, designing a process digital model: the titanium alloy structural part is divided into beams, frames, joints, wall plates and ribs, and a part digital model is designed into a process digital model according to the characteristics of a synchronous powder feeding additive manufacturing process;

step 2, characteristic partitioning: carrying out layered slicing processing on the process digital analogy, carrying out region division on each layer of sheet data according to structural characteristics, and dividing each type of titanium alloy structural part into a plane type, a cross type, an I shape, a straight type, a T shape and an L shape;

step 3, designing an additive manufacturing process: optimizing the structural characteristic synchronous powder feeding additive manufacturing process and the process parameters to form a database, and carrying out research on the design of the subsequent additive manufacturing process of specific parts to efficiently finish the design of the additive manufacturing process with high quality;

the specific method of the step 2 comprises the following steps:

step 2.1, carrying out layered slicing treatment on the process digital model: for parts with simple shapes, carrying out layered slicing according to the given layer thickness according to the design and the selected growth direction; selecting a main growth direction for parts with complex shapes, dividing a cantilever or other parts which are not suitable for one-time additive manufacturing, slicing the parts in a layered mode according to the main growth direction, and then rotating a digital model to slice the parts in a layered mode according to the divided parts in a secondary growth direction to obtain a group of slice data;

step 2.2, partitioning the slice data according to the structural characteristics: each layer sheet is divided according to regions to obtain a plurality of region combinations with simple configuration characteristics, a large number of parts are sliced in layers and the regions are divided, and the characteristics are summarized to obtain six structural configurations of a plane type, a cross type, an I type, a straight type, a T type and an L type;

and 2.3, obtaining the sizes of a plane type, a cross type, an I shape, a straight shape, a T shape and an L shape after characteristic partitioning, wherein the specific sizes of the length and the width of the components in the characteristics are adjusted and optimized by combining the size of the process digital model corresponding to each layer of the slice data and the synchronous powder feeding additive manufacturing process.

2. The method for planning the synchronous powder feeding additive manufacturing process based on the structural characteristics as claimed in claim 1, wherein the method comprises the following steps: the specific method of the step 1 comprises the following steps:

according to the characteristics of the synchronous powder feeding additive manufacturing process, removing some fine structures of a specific part model, carrying out model regularization treatment, adding a process support, designing a substrate, selecting an additive manufacturing deposition growth direction, and designing into the additive manufacturing process model;

step 1.1, removing a fine structure: removing fine structures such as micro holes, grooves and small bosses of part data according to an additive manufacturing process, increasing the wall thickness of the part, and reserving nondestructive testing and machining allowance;

step 1.2, carrying out regularization treatment on the model according to the characteristics of the shape and the material characteristics of the part;

step 1.3, designing and selecting an additive growth direction and adding a process support: according to the size of the projection sectional area of the part space X, Y, Z in three directions, the minimum direction of the sectional area is used as the growth direction of additive manufacturing deposition, and the growth direction is supported by cantilever adding process.

3. The method for planning the synchronous powder feeding additive manufacturing process based on the structural characteristics as claimed in claim 1, wherein the method comprises the following steps: the specific method of the step 3 comprises the following steps:

3.1, according to the form, the size and the laser power of equipment, conducting theoretical analysis and experimental verification on typical structural characteristics, namely a planar type, a cross type, an I shape, a straight type, a T shape and an L shape, of the additive manufacturing process summarized from mass parts, finally solidifying the process and working steps, optimizing process parameters, summarizing parameter sets of laser power P, scanning speed V, powder feeding speed F, scanning interval I and layering thickness delta h of each structural configuration, and establishing an additive manufacturing process database based on characteristic partitioning;

and 3.2, for a new part needing additive manufacturing, firstly, carrying out layered slicing on the process digital model, partitioning according to structural features, then calling parameters from a process parameter library, and finishing additive manufacturing process design with high efficiency and high quality.

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