Additive manufacturing composite forming method and TC4 titanium alloy part

Abstract

The invention provides an additive manufacturing composite forming method and a TC4 titanium alloy part, and relates to the field of aircraft part forging, and the method comprises the steps that a TC4 titanium alloy matrix forge piece is obtained; 3D printing additive manufacturing is conducted on a TC4 titanium alloy matrix forge piece through TC4 additive powder, and the TC4 titanium alloy composite forge piece is obtained. The method is suitable for the manufacturing and forming process of complex parts and is used for solving the problem that forging forming is difficult in some situations.

Description

Technical Field

[0001] This application relates to the field of aircraft component forging, and particularly to an additive manufacturing composite forming method and a TC4 titanium alloy part. Background Art

[0002] Forging processes mainly have the characteristics of dense product structure, good mechanical properties, and relatively high production efficiency.

[0003] However, its forming is often restricted by the structural characteristics of the product. Especially during the forging of aircraft components, when the interface change rate of the forging is large or it contains structures such as thin flange ribs and webs, the process difficulty increases significantly, and it is often necessary to additionally increase the weight of the input material, resulting in an increase in production costs. When the material is a metal material with high resistance or poor plasticity, it is difficult to achieve through forging forming. Summary of the Invention

[0004] This application provides an additive manufacturing composite forming method to solve the problem that it is difficult to form by forging in some cases.

[0005] In a first aspect, this application provides an additive manufacturing composite forming method, which includes: obtaining a TC4 titanium alloy matrix forging; performing 3D printing additive manufacturing on the TC4 titanium alloy matrix forging using TC4 additive powder to obtain a TC4 titanium alloy composite forging.

[0006] The additive manufacturing composite forming method provided by this application can perform 3D printing additive manufacturing on the TC4 titanium alloy matrix forging to obtain a TC4 titanium alloy composite forging. In this way, the advantages of fast speed, low cost of forging and the dexterity, complex structure, and mold-free of additive manufacturing can be perfectly combined. Eventually, the processes of complex products can be simplified, the cycle can be shortened, and the tooling equipment can be simplified, achieving the purpose of increasing efficiency and reducing costs.

[0007] Optionally, the method further includes: performing hot working on the TC4 titanium alloy composite forging.

[0008] Optionally, performing hot working on the TC4 titanium alloy composite forging includes: rolling the TC4 titanium alloy composite forging.

[0009] Optionally, obtaining the TC4 titanium alloy matrix forging includes: preparing a TC4 titanium alloy bar with a diameter of 120 mm and a height of 172 mm; forging the TCR titanium alloy bar into a rectangular ring intermediate blank with an outer diameter of 220 mm ± 3 mm, an inner diameter of 90 mm ± 3 mm, and a height of 60 mm ± 3 mm by upsetting and punching, and the forging temperature is 40 °C below the β transformation temperature; processing the rectangular ring intermediate blank according to the dimensions of an outer diameter of 210 mm ± 1 mm, an inner diameter of 100 mm ± 1 mm, and a height of 100 mm ± 1 mm to obtain the TC4 titanium alloy matrix forging.

[0010] Optionally, hot working is performed on the TC4 titanium alloy composite forging, including: die forging the TC4 titanium alloy composite forging.

[0011] Optionally, obtaining a TC4 titanium alloy matrix forging includes: obtaining a TC4 titanium alloy bar with a diameter of 70 mm and a height of 70 mm as the TC4 titanium alloy matrix forging; the TC4 titanium alloy bar is forged based on a TC4 titanium alloy blank.

[0012] In the additive manufacturing composite forming method provided by this application, the tissue uniformity of the rectangular ring blank prepared by forging + 3D additive manufacturing after hot working is improved, and at the same time, the single display existing at the interface between the matrix and the 3D printed additive manufacturing part is eliminated. For the bar blank prepared by forging + 3D additive manufacturing after hot working, the tissue boundary is effectively improved.

[0013] Optionally, the method further includes: sampling at the TC4 titanium alloy matrix forging part, the 3D printed additive manufacturing part, and the interface part between the TC4 titanium alloy matrix forging part and the 3D printed additive manufacturing part of the TC4 titanium alloy composite forging respectively to obtain a plurality of specimens; testing the mechanical properties of the plurality of specimens respectively.

[0014] Optionally, the method further includes: cutting the TC4 titanium alloy composite forging in a direction perpendicular to the interface; the interface is the interface between the TC4 titanium alloy matrix forging part and the 3D printed additive manufacturing part; analyzing the 3D printed additive manufacturing defects based on the cutting section; the 3D printed additive manufacturing defects include pores and unmelted powder inclusions.

[0015] Optionally, the method further includes: performing flaw detection bottom wave C scanning on the target plane of the TC4 titanium alloy composite forging before and after hot working respectively; the target plane is a plane perpendicular to the interface; the interface is the interface between the TC4 titanium alloy matrix forging part and the 3D printed additive manufacturing part; analyzing the boundary situation between the TC4 titanium alloy matrix forging part and the 3D printed additive manufacturing part before and after hot working according to the results of the flaw detection bottom wave C scanning.

[0016] In the second aspect, this application provides a TC4 titanium alloy part, and the TC4 titanium alloy part is manufactured by using the additive manufacturing composite forming method described in the first aspect above.

[0017] The beneficial effects of the above second aspect can be referred to those described in the first aspect above, and will not be elaborated here. Description of the Drawings

[0018] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0019] Figure 1 This is a rectangular ring blank prepared by forging + 3D additive manufacturing provided by the embodiment of the present application; Figure 2 This is a physical diagram of a rectangular ring formed by the forging + 3D additive manufacturing + ring rolling composite process provided by the embodiment of the present application; Figure 3 This is a physical diagram of a bar blank for die pressing prepared by forging + 3D additive manufacturing provided by the embodiment of the present application; Figure 4 This is a physical diagram of a die forging formed by the forging + 3D additive manufacturing + die pressing composite process provided by the embodiment of the present application; Figure 5 This is a schematic diagram showing the end face flaw detection sheet of a rectangular ring blank prepared by forging + 3D additive manufacturing provided by the embodiment of the present application; Figure 6 This is a schematic diagram of the bottom wave C-scan of the circumferential surface of a rectangular ring blank prepared by forging + 3D additive manufacturing provided by the embodiment of the present application; Figure 7 This is a schematic diagram of the bottom wave C-scan of the circumferential surface of a rectangular ring formed by the forging + 3D additive manufacturing + ring rolling composite process provided by the embodiment of the present application; Figure 8 This is a schematic diagram of the bottom wave C-scan of the circumferential surface of a bar blank prepared by forging + 3D additive manufacturing before die pressing provided by the embodiment of the present application; Figure 9 This is a schematic diagram of the bottom wave C-scan of the large flat surface of a bar blank prepared by forging + 3D additive manufacturing after die pressing provided by the embodiment of the present application; Figure 10 This is a schematic diagram of the macrostructure of the diameter axial plane of a rectangular ring formed by the forging + 3D additive manufacturing + ring rolling composite process provided by the embodiment of the present application; Figure 11 This is a schematic diagram of the macrostructure of the cross section of a die forging formed by the forging + 3D additive manufacturing + die pressing composite process provided by the embodiment of the present application; Figure 12 This is a sampling diagram of a rectangular ring formed by the forging + 3D additive manufacturing + ring rolling composite process provided by the embodiment of the present application; Figure 13 This is a sampling diagram of a die forging formed by the forging + 3D additive manufacturing + die pressing composite process provided by the embodiment of the present application; Figure 14The high-magnification tissue diagram provided by the embodiments of the present application; Figure 15 The schematic flow chart of the additive manufacturing composite forming method provided by the embodiments of the present application. Detailed implementation manners

[0020] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0021] It should be noted that in the embodiments of the present application, words such as "exemplarily" or "for example" are used to represent examples, illustrations or explanations. Any embodiment or design solution described as "exemplarily" or "for example" in the embodiments of the present application should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Exactly speaking, using words such as "exemplarily" or "for example" is intended to present related concepts in a specific manner.

[0022] In order to facilitate the clear description of the technical solutions in the embodiments of the present application, in the embodiments of the present application, words such as "first" and "second" are used to distinguish the same items or similar items with basically the same functions and effects. Those skilled in the art can understand that the words such as "first" and "second" do not limit the quantity and execution order.

[0023] The forging process mainly has the characteristics of dense product structure, good mechanical properties, and relatively high production efficiency.

[0024] However, its forming is often restricted by the structural characteristics of the product. Especially in the forging process of aircraft parts, when the interface change rate of the forging is large or there are structures such as thin flange ribs and webs, the process difficulty increases significantly, and it is often necessary to additionally increase the weight of the input material, resulting in an increase in the production cost. When the material is a metal material with high resistance or poor plasticity, it is difficult to achieve by forging.

[0025] 3D additive manufacturing has the characteristics of strong processing arbitrariness, complex formed structures, and short R & D cycles. Although additive manufacturing has advantages that traditional forging does not have, additive manufacturing is slow and time-consuming in the material manufacturing link. Especially for large parts in aerospace, a single part sometimes takes several months.

[0026] Based on this, the embodiments of the present application provide an additive manufacturing composite forming method and a TC4 titanium alloy part, which can combine forging and 3D printing additive manufacturing to simplify the processes of complex products, shorten the cycle, simplify the tooling equipment, etc., so as to achieve the purpose of cost reduction and efficiency improvement. It provides a new idea for the forming technology of large and complex aviation forgings.

[0027] First, conduct experimental analysis on the feasibility of forging + 3D additive manufacturing.

[0028] (1) Test materials.

[0029] In the experiment, the material used for the forging matrix is conventional TC4 titanium alloy. The raw material procurement standard is GJB2218A - 2018. The specific specifications may include bars with a diameter of 120 millimeters (mm) and bars with a diameter of 70 mm. The additive used for 3D additive manufacturing is TC4 additive powder, and the procurement standard is GJB9577.

[0030] (2) Conduct the experiment.

[0031] A. Prepare a TC4 titanium alloy bar with a diameter of 120 mm and a height of 172 mm. Prepare an intermediate ring blank with an outer diameter of 220 mm ± 3 mm, an inner diameter of 90 mm ± 3, and a height of 60 mm ± 3 mm from the bar through the processes of upsetting and punching. The forging heating temperature is (Tβ - 40) °C. Machine the forging intermediate blank to an outer diameter of 210 mm ± 1 mm, an inner diameter of 100 mm ± 1 mm, and a height of 50 mm ± 1 mm. The machined rectangular ring blank is used as the matrix for additive manufacturing. Conduct 3D printing additive manufacturing at either end of the matrix to finally form a rectangular ring blank prepared by forging + 3D additive manufacturing with an outer diameter of 210 mm ± 1 mm, an inner diameter of 100 mm ± 1 mm, and a height of 100 mm ± 1 mm.

[0032] Exemplarily, Figure 1 This is the rectangular ring blank prepared by forging + 3D additive manufacturing provided by the embodiments of the present application. As Figure 1 shown in (a) of Figure 1 , the overall height of the rectangular ring blank prepared by forging + 3D additive manufacturing is 100 mm. The lower 50 mm is the matrix obtained by forging, and the upper 50 mm is the part of 3D additive manufacturing on the matrix. As Figure 1 shown in (b) of

[0033] Roll the rectangular ring blank prepared by forging + 3D additive manufacturing. The rolling heating temperature is (Tβ - 40) °C. Roll it to the size of an outer diameter of 256 mm, an inner diameter of 180 mm, and a height of 100 mm to finally form a rectangular ring prepared by the forging + 3D additive manufacturing + ring rolling composite process.

[0034] Exemplarily, Figure 2 This is a physical diagram of a rectangular ring formed by the forging + 3D additive manufacturing + ring rolling composite process provided by the embodiments of the present application. As Figure 2 shown, Figure 2 the physical image of the rectangular ring formed by the forging + 3D additive manufacturing + ring rolling composite process shown in

[0035] B. Prepare a TC4 titanium alloy bar with a diameter of 70 mm and a height of 70 mm. Use the bar as the substrate for additive manufacturing and perform 3D printing additive manufacturing at any end. Finally, a bar blank for die forging prepared by forging + 3D additive manufacturing with a diameter of 70 mm ± 1 mm and a height of 140 mm ± 1 mm is formed.

[0036] Exemplarily, Figure 3 This is a physical diagram of the bar blank for die forging prepared by forging + 3D additive manufacturing provided by the embodiments of the present application. Please refer to Figure 3 , Figure 3 where the physical image of the bar blank for die forging prepared by forging + 3D additive manufacturing is shown.

[0037] Perform die forging deformation on the intermediate bar blank, and the rolling heating temperature is (Tβ - 40) °C. Finally, a die forging prepared by the forging + 3D additive manufacturing + die forging composite process is formed.

[0038] Exemplarily, Figure 4 This is a physical diagram of the die forging formed by the forging + 3D additive manufacturing + die forging composite process provided by the embodiments of the present application. As Figure 4 shown, Figure 4 where the physical image of the die forging formed by the forging + 3D additive manufacturing + die forging composite process is shown.

[0039] (3). Result analysis.

[0040] A. Analysis of the rectangular ring formed by the forging + 3D additive manufacturing + ring rolling composite process.

[0041] Exemplarily, Figure 5 This is a schematic diagram showing the end face flaw detection of the rectangular ring blank prepared by forging + 3D additive manufacturing provided by the embodiments of the present application. As Figure 5 shown, before the rectangular ring blank prepared by forging + 3D additive manufacturing undergoes ring rolling, there is a single display at the interface between the substrate and the 3D printed additive manufacturing part, and the depth from the end face is about 49.3 mm. This single display is pores or unmelted powder existing during the additive manufacturing process.

[0042] Exemplarily, Figure 6 This is a schematic diagram of the C-scan of the bottom wave of the circumferential surface flaw detection of the rectangular ring blank prepared by forging + 3D additive manufacturing provided by the embodiments of the present application. As Figure 6As shown, there is an obvious boundary between the matrix and the part formed by 3D additive manufacturing in the rectangular ring blank prepared by forging + 3D additive manufacturing before ring rolling.

[0043] Exemplarily, Figure 7 This is a schematic diagram of the C-scan of the bottom wave for circumferential surface flaw detection of a rectangular ring formed by the forging + 3D additive manufacturing + ring rolling composite process provided by the embodiment of the present application. As Figure 7 shown, after subsequent hot working, the tissue uniformity of the rectangular ring blank prepared by forging + 3D additive manufacturing is improved, and at the same time, the single display existing at the interface between the matrix and the 3D printing additive manufacturing part is eliminated.

[0044] B. Analysis of the die forging formed by the forging + 3D additive manufacturing + die pressing composite process.

[0045] Flaw detection is carried out on the bar blank prepared by forging + 3D additive manufacturing and the die forging prepared by the forging + 3D additive manufacturing + die pressing composite process.

[0046] Exemplarily, Figure 8 This is a schematic diagram of the C-scan of the bottom wave for the circumferential surface of the bar blank prepared by forging + 3D additive manufacturing provided by the embodiment of the present application before die pressing. As Figure 8 shown, through the display of the bottom wave, there is an obvious boundary between the matrix and the part formed by 3D additive manufacturing in the bar blank prepared by forging + 3D additive manufacturing before die pressing.

[0047] Exemplarily, Figure 9 This is a schematic diagram of the C-scan of the large plane bottom wave of the bar blank prepared by forging + 3D additive manufacturing after die pressing provided by the embodiment of the present application. As Figure 9 shown, the tissue boundary is effectively improved after die pressing.

[0048] C. Macrostructure observation.

[0049] Exemplarily, Figure 10 This is a schematic diagram of the macrostructure of the diameter axial plane of a rectangular ring formed by the forging + 3D additive manufacturing + ring rolling composite process provided by the embodiment of the present application. Figure 11 This is a schematic diagram of the macrostructure of the cross-section of a die forging formed by the forging + 3D additive manufacturing + die pressing composite process provided by the embodiment of the present application.

[0050] As Figure 10 and Figure 11 shown, in the rectangular ring prepared by the forging + 3D additive manufacturing + ring rolling composite process and the die forging prepared by the forging + 3D additive manufacturing + die pressing composite process, the interface between the matrix and the 3D printing additive part is clearly visible, and the organizational structures on both sides are significantly different, which is consistent with the reaction of the flaw detection bottom wave C-scan. No common 3D additive manufacturing defects such as pores and unmelted powder inclusions are found at the interface.

[0051] D. Mechanical properties of the rectangular ring formed by forging + 3D additive manufacturing + ring rolling composite process.

[0052] Exemplarily, Figure 12 This is the sampling diagram of the rectangular ring formed by the forging + 3D additive manufacturing + ring rolling composite process provided in the embodiment of the present application. As Figure 12 shown, the sampling positions 1, 2, 3, and 4 are parts of 3D additive manufacturing, the sampling positions 5, 6, 7, and 8 are parts of the forging matrix, and the sampling positions 9, 10, 11, and 12 are the interfaces between forging and 3D printing additive.

[0053] The specimens obtained by sampling are tested to obtain the room temperature tensile and high temperature tensile strengths, and the results are shown in Table 1 and Table 2 as follows: Table 1: Room temperature tensile properties of the rectangular ring formed by forging + 3D additive manufacturing + ring rolling composite process As shown in Table 1, during the room temperature tensile test, the tensile strength at the test position of 1 chord is 860 MPa (MPa), the yield strength is 790 MPa, the 5D elongation after fracture is 13.5%, and the reduction of area is 50%. The tensile strength at the test position of 2 chord is 905 MPa, the yield strength is 825 MPa, the 5D elongation after fracture is 12.0%, and the reduction of area is 36%. The tensile strength at the test position of 5 chord is 975 MPa, the yield strength is 895 MPa, the 5D elongation after fracture is 18.0%, and the reduction of area is 46%. The tensile strength at the test position of 6 chord is 975 MPa, the yield strength is 895 MPa, the 5D elongation after fracture is 16.0%, and the reduction of area is 45%. The tensile strength at the test position of 9 axis is 855 MPa, the yield strength is 780 MPa, the 5D elongation after fracture is 13.0%, and the reduction of area is 49%. The tensile strength at the test position of 10 axis is 880 MPa, the yield strength is 800 MPa, the 5D elongation after fracture is 10.0%, and the reduction of area is 39%.

[0054] Table 2: High temperature tensile properties of the rectangular ring formed by forging + 3D additive manufacturing + ring rolling composite process As shown in Table 2, during the high-temperature tensile test, the tensile strength at the 3 chord direction of the test position is 584.5 MPa, the yield strength is 469 MPa, the elongation after fracture at 5D is 18.5%, and the reduction of area is 65.5%. The tensile strength at the 4 chord direction of the test position is 602 MPa, the yield strength is 490 MPa, the elongation after fracture at 5D is 17.5%, and the reduction of area is 65.0%. The tensile strength at the 7 chord direction of the test position is 647.5 MPa, the yield strength is 525 MPa, the elongation after fracture at 5D is 16.5%, and the reduction of area is 63.0%. The tensile strength at the 8 chord direction of the test position is 651 MPa, the yield strength is 525 MPa, the elongation after fracture at 5D is 17.5%, and the reduction of area is 64.0%. The tensile strength at the 11 axial direction of the test position is 577.5 MPa, the yield strength is 472.5 MPa, the elongation after fracture at 5D is 19.0%, and the reduction of area is 71.5%. The tensile strength at the 12 axial direction of the test position is 570.5 MPa, the yield strength is 462 MPa, the elongation after fracture at 5D is 19.5%, and the reduction of area is 72.0%.

[0055] E. Mechanical properties of die forgings formed by forging + 3D additive manufacturing + molding composite process

[0056] Exemplarily, Figure 13 is the sampling diagram of die forgings formed by forging + 3D additive manufacturing + molding composite process provided by the embodiments of the present application. As Figure 13 shown, the sampling positions 1, 2, 9, and 10 are parts of 3D additive manufacturing, the sampling positions 7, 8, 11, and 12 are parts of the forging matrix, and the sampling positions 3, 4, 5, and 6 are the interfaces between forging and 3D printing additive manufacturing.

[0057] The room-temperature tensile and high-temperature tensile strengths are obtained by testing the sampled specimens, and the results are as shown in Table 3 and Table 4 below: Table 3: Room-temperature tensile properties of die forgings formed by forging + 3D additive manufacturing + molding composite process As shown in Table 3, during the room temperature tensile test, the tensile strength at the transverse position of 1 is 875 MPa, the yield strength is 825 MPa, the elongation after fracture at 5D is 11.0%, and the reduction of area is 44%. The tensile strength at the transverse position of 2 is 875 MPa, the yield strength is 825 MPa, the elongation after fracture at 5D is 11.5%, and the reduction of area is 45%. The tensile strength at the transverse position of 7 is 970 MPa, the yield strength is 895 MPa, the elongation after fracture at 5D is 16.0%, and the reduction of area is 49%. The tensile strength at the transverse position of 8 is 960 MPa, the yield strength is 875 MPa, the elongation after fracture at 5D is 17.5%, and the reduction of area is 44%. The tensile strength at the longitudinal position of 3 is 930 MPa, the yield strength is 890 MPa, the elongation after fracture at 5D is 7.0%, and the reduction of area is 43%. The tensile strength at the longitudinal position of 4 is 895 MPa, the yield strength is 840 MPa, the elongation after fracture at 5D is 10.0%, and the reduction of area is 46%.

[0058] Table 4: High-temperature tensile properties of die forgings formed by forging + 3D additive manufacturing + molding composite process As shown in Table 4, during the high-temperature tensile test, the tensile strength at the transverse position of 9 is 623 MPa, the yield strength is 514.5 MPa, the elongation after fracture at 5D is 17.5%, and the reduction of area is 75.5%. The tensile strength at the transverse position of 10 is 598.5 MPa, the yield strength is 486.5 MPa, the elongation after fracture at 5D is 20.5%, and the reduction of area is 68.0%. The tensile strength at the transverse position of 11 is 654.5 MPa, the yield strength is 525 MPa, the elongation after fracture at 5D is 18.0%, and the reduction of area is 66.5%. The tensile strength at the transverse position of 12 is 644 MPa, the yield strength is 521.5 MPa, the elongation after fracture at 5D is 19.5%, and the reduction of area is 68.0%. The tensile strength at the longitudinal position of 5 is 605.5 MPa, the yield strength is 486.5 MPa, the elongation after fracture at 5D is 19.0%, and the reduction of area is 49.5%. The tensile strength at the longitudinal position of 6 is 602 MPa, the yield strength is 507.5 MPa, the elongation after fracture at 5D is 18.5%, and the reduction of area is 72.5%.

[0059] F. High-magnification microstructure observation.

[0060] Specimens were cut from the forging matrix, the bonding interface, and the 3D printed additive manufacturing part for microstructure analysis respectively.

[0061] Exemplarily, Figure 14 is the high-magnification microstructure diagram provided by the embodiment of the present application. AsFigure 14 As shown in (a) in [reference], it is a typical representative microstructure. This microstructure is the typical bimodal microstructure of TC4, which consists of primary α phase and β phase matrix, and fine secondary α phase is distributed in the β matrix. As Figure 14 As shown in (b) and (c) in [reference], it is the microstructure of the 3D printing additive manufacturing part. The microstructure of the additive manufacturing part is that α phase with thick lamellae is distributed on the β matrix. As Figure 14 As shown in (d) in [reference], it is the microstructure at the interface bonding part. The microstructure at the interface bonding part is complex, with the primary α phase of the matrix, and at the same time, α phase with thick lamellae is distributed on the β matrix.

[0062] Based on the understanding of the above embodiments, the embodiments of the present application provide an additive manufacturing composite forming method. Figure 15 It is a schematic flow chart of the additive manufacturing composite forming method provided by the embodiments of the present application. As Figure 15 shown, this method includes the following steps: S101. Obtain a TC4 titanium alloy matrix forging.

[0063] In some possible embodiments, as described in the rectangular ring formed by the above forging + 3D additive manufacturing + ring rolling composite process, the matrix forging can be a rectangular ring. In this case, the above S101 can specifically include the following steps: Step 1a. Prepare a TC4 titanium alloy bar with a diameter of 120 mm and a height of 172 mm.

[0064] Step 2a. Upset and punch the TCR titanium alloy bar into an intermediate blank of a rectangular ring with an outer diameter of 220 mm ± 3 mm, an inner diameter of 90 mm ± 3 mm, and a height of 60 mm ± 3 mm. The forging temperature is 40 °C below the β transformation temperature.

[0065] Step 3a. Process the intermediate blank of the rectangular ring according to the dimensions of an outer diameter of 210 mm ± 1 mm, an inner diameter of 100 mm ± 1 mm, and a height of 100 mm ± 1 mm to obtain a TC4 titanium alloy matrix forging.

[0066] Steps 1a to 3a can be referred to as described in A in the above (2) during the experiment, and will not be elaborated here.

[0067] In some other possible embodiments, as described in the die forging formed by the above forging + 3D additive manufacturing + die pressing composite process, the matrix forging can be a TC4 titanium alloy bar. In this case, the above S101 can specifically include the following steps: Step 1b. Obtain a TC4 titanium alloy bar with a diameter of 70 mm and a height of 70 mm as the TC4 titanium alloy matrix forging.

[0068] Among them, the TC4 titanium alloy bar is forged based on a TC4 titanium alloy blank.

[0069] Step 1b can be carried out with reference to B described in the above (2) during the experiment, which will not be elaborated here.

[0070] S102. Perform 3D printing additive manufacturing on the TC4 titanium alloy matrix forging using TC4 additive powder to obtain a TC4 titanium alloy composite forging.

[0071] The additive manufacturing composite forming method provided by the embodiments of the present application can perform 3D printing additive manufacturing on the TC4 titanium alloy matrix forging to obtain a TC4 titanium alloy composite forging. In this way, the advantages of forging, such as high speed and low cost, can be perfectly combined with the characteristics of additive manufacturing, such as flexibility, complex structure, and no need for molds. Ultimately, the process of complex products can be simplified, the cycle can be shortened, and the tooling equipment can be simplified, achieving the purpose of increasing efficiency and reducing costs.

[0072] In some embodiments, after obtaining the TC4 titanium alloy composite forging, the method may further include: performing hot working on the TC4 titanium alloy composite forging.

[0073] In a possible implementation manner, for the rectangular ring formed by the above forging + 3D additive manufacturing + ring rolling composite process, the steps of hot working may specifically include: rolling the TC4 titanium alloy composite forging. Specifically, it can be carried out with reference to A described in the above (2) during the experiment, which will not be elaborated here.

[0074] In another possible implementation manner, for the die forging prepared by the above forging + 3D additive manufacturing + die pressing composite process, the steps of hot working may specifically include: die pressing the TC4 titanium alloy composite forging. Specifically, it can be carried out with reference to B described in the above (2) during the experiment, which will not be elaborated here.

[0075] It should be understood that as described in A, B, and C in the above (3) result analysis, the tissue uniformity of the rectangular ring blank prepared by forging + 3D additive manufacturing after hot working is improved, and at the same time, the single display existing at the interface between the matrix and the 3D printing additive manufacturing part is eliminated. For the bar blank prepared by forging + 3D additive manufacturing after hot working, the tissue demarcation is effectively improved.

[0076] In some possible embodiments, after obtaining the TC4 titanium alloy composite forging, mechanical property testing can also be performed. In this case, the method may further include the following steps: Step 1c. Sample from the TC4 titanium alloy matrix forging part, the 3D printing additive manufacturing part, and the interface part between the TC4 titanium alloy matrix forging part and the 3D printing additive manufacturing part of the TC4 titanium alloy composite forging to obtain a plurality of specimens.

[0077] Step 2c. Test the mechanical properties of the plurality of specimens respectively.

[0078] Steps 1c and 2c can be carried out as described in D and E in the above-mentioned (3) Results Analysis, and will not be elaborated here.

[0079] In some other possible embodiments, after obtaining the TC4 titanium alloy composite forging, macrostructure observation and analysis can also be performed. In this case, the method may further include the following steps: Step 1d: Cut the TC4 titanium alloy composite forging in a direction perpendicular to the interface.

[0080] Wherein, the interface is the interface between the TC4 titanium alloy matrix forging part and the 3D printing additive manufacturing part.

[0081] Step 2d: Analyze the 3D printing additive manufacturing defects based on the cut section.

[0082] Wherein, the 3D printing additive manufacturing defects include pores and unmelted powder inclusions.

[0083] Steps 1d and 2d can be carried out as described in C in the above-mentioned (3) Results Analysis, and will not be elaborated here.

[0084] In still some other possible embodiments, the method may further include the following steps: Step 1e: Perform flaw detection bottom wave C-scanning on the target plane of the TC4 titanium alloy composite forging before and after hot working respectively.

[0085] Wherein, the target plane is a plane perpendicular to the interface, and the interface is the interface between the TC4 titanium alloy matrix forging part and the 3D printing additive manufacturing part.

[0086] Step 2e: Analyze the boundary situation between the TC4 titanium alloy matrix forging part and the 3D printing additive manufacturing part before and after hot working according to the results of the flaw detection bottom wave C-scanning.

[0087] Steps 1e and 2e can be carried out as described in A and B in the above-mentioned (3) Results Analysis, and will not be elaborated here.

[0088] The technical solutions of the embodiments of the present application have been introduced from the perspective of the method above. In an exemplary embodiment, the embodiments of the present application further provide a TC4 titanium alloy part, and this TC4 titanium alloy part is manufactured by using the additive manufacturing composite forming method provided in the above method embodiment.

[0089] Although the present application has been described in connection with specific features and their embodiments, it will be apparent that various modifications and combinations can be made without departing from the spirit and scope of the present application. Accordingly, the present specification and the drawings are merely exemplary illustrations of the present application as defined by the appended claims, and are considered to cover any and all modifications, variations, combinations, or equivalents within the scope of the present application. Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application is also intended to include these changes and modifications.

[0090] As described above, it is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An additive manufacturing composite molding method, characterized in that, The method includes: Obtaining a TC4 titanium alloy matrix forging; Performing 3D printing additive manufacturing on the TC4 titanium alloy matrix forging using TC4 additive powder to obtain a TC4 titanium alloy composite forging.

2. The method according to claim 1, wherein The method further includes: Performing hot working on the TC4 titanium alloy composite forging.

3. The method according to claim 2, wherein The performing hot working on the TC4 titanium alloy composite forging includes: Rolling the TC4 titanium alloy composite forging.

4. The method according to claim 3, characterized in that, The obtaining a TC4 titanium alloy matrix forging includes: Preparing a TC4 titanium alloy bar with a diameter of 120 mm and a height of 172 mm; Forging the TCR titanium alloy bar into a rectangular ring intermediate blank with an outer diameter of 220 mm ± 3 mm, an inner diameter of 90 mm ± 3 mm, and a height of 60 mm ± 3 mm by upsetting and punching, and the forging temperature is 40 °C below the β transformation temperature; Machining the rectangular ring intermediate blank according to the dimensions of an outer diameter of 210 mm ± 1 mm, an inner diameter of 100 mm ± 1 mm, and a height of 100 mm ± 1 mm to obtain the TC4 titanium alloy matrix forging.

5. The method according to claim 2, wherein The performing hot working on the TC4 titanium alloy composite forging includes: Performing die pressing on the TC4 titanium alloy composite forging.

6. The method according to claim 5, characterized in that, The obtaining a TC4 titanium alloy matrix forging includes: Obtaining a TC4 titanium alloy bar with a diameter of 70 mm and a height of 70 mm as the TC4 titanium alloy matrix forging; the TC4 titanium alloy bar is forged based on a TC4 titanium alloy blank.

7. The method according to claim 2, wherein, The method further includes: Sampling respectively at the TC4 titanium alloy matrix forging part, the 3D printing additive manufacturing part, and the interface part between the TC4 titanium alloy matrix forging part and the 3D printing additive manufacturing part of the TC4 titanium alloy composite forging to obtain a plurality of specimens; Testing the mechanical properties of the plurality of specimens respectively.

8. The method according to claim 1, wherein The method further includes: Cutting the TC4 titanium alloy composite forging in a direction perpendicular to the interface; the interface is the interface between the TC4 titanium alloy matrix forging part and the 3D printing additive manufacturing part; Analyzing 3D printing additive manufacturing defects based on the cut section; the 3D printing additive manufacturing defects include pores and unmelted powder slag inclusions.

9. The method according to claim 2, characterized in that The method further includes: Performing flaw detection bottom wave C-scanning on the target plane of the TC4 titanium alloy composite forging before and after hot working respectively; the target plane is a plane perpendicular to the interface; the interface is the interface between the TC4 titanium alloy matrix forging part and the 3D printing additive manufacturing part; Analyzing the boundary situation between the TC4 titanium alloy matrix forging part and the 3D printing additive manufacturing part before and after hot working according to the results of the flaw detection bottom wave C-scanning.

10. A TC4 titanium alloy part, characterized in that, The TC4 titanium alloy part is manufactured by using the additive manufacturing composite forming method according to any one of claims 1-9.

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