An alloy material for additive manufacturing and additive manufacturing method and application thereof

Abstract

The application relates to an alloy material for additive manufacturing and an additive manufacturing method and application thereof, and belongs to the technical field of additive manufacturing. The alloy material for additive manufacturing comprises the following components in percentage by weight: C 0.005%-0.1%, Ni 12%-33%, Co 12%-38%, Al 0.05%-2%, Ti 0.05%-2%, Si 0.02%-0.2%, N 0.05%-0.2% and Fe 36%-75%. The alloy material has excellent additive manufacturing process performance, good heat conduction performance and rust prevention performance, can improve die temperature uniformity, improve product quality, improve production efficiency, meet the use requirement strength of an injection mold and has low cost.

Description

Technical Field

[0001] This application relates to the field of additive manufacturing technology, and in particular to an alloy material for additive manufacturing, an additive manufacturing method thereon, and its application. Background Technology

[0002] Molds, often hailed as the "mother of industry," play a vital role in industrial production. Injection molds, in particular, account for 43% of the total domestic mold output, making them the most important mold product. The cooling process of injection molds accounts for over 50% of the entire molding cycle; therefore, the effectiveness of mold cooling is crucial for improving product production efficiency. In recent years, additive manufacturing technology has enabled the fabrication and application of conformal cooling water channel molds for complex structural products, significantly improving cooling efficiency and temperature distribution. However, the inherent properties of materials (thermal conductivity below 20 W / m·K) have created a significant ceiling for improving cooling efficiency, hindering efforts to shorten product production cycles, reduce warpage, and expedite product delivery.

[0003] The thermal conductivity of alloy materials is closely related to alloy composition, microstructure, and heat treatment process. Existing technologies have improved thermal conductivity by reducing the Cr content in the alloy, resulting in the development of HTC130 alloy. However, excessively low Cr content significantly impairs the material's rust resistance. Especially for injection molds with conformal water channels, high thermal conductivity alloys with low Cr content easily cause blockage of the conformal water channels, failing to achieve the effect of shortening the injection cycle. Recent studies have found that equiatomic FeCoNi high-entropy alloys have low resistivity and excellent corrosion resistance; however, equiatomic FeCoNi alloys have an FCC face-centered cubic structure and low tensile strength (320 MPa), which does not meet the requirements for mold materials. Furthermore, Chinese patent CN112301255 discloses a Co-Fe-Ni high-conductivity, high-strength mold steel material with a high Co content (over 44%). However, Co is a strategic element with a high price, resulting in a material cost far exceeding current mold steel materials, limiting its application in the civilian injection mold steel field. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the objective of this application is to provide an alloy material for additive manufacturing that possesses excellent additive manufacturing process performance, good thermal conductivity and rust prevention properties, and can improve mold temperature uniformity, product quality, production efficiency, meet the strength requirements of injection molds, and has low cost.

[0005] In a first aspect, embodiments of this application provide an alloy material for additive manufacturing, the alloy material comprising the following components by weight percentage: C 0.005%-0.1%, Ni 12%-33%, Co 12%-38%, Al 0.05%-2%, Ti 0.05%-2%, Si 0.02%-0.2%, N 0.05%-0.2%, and Fe 36%-75%.

[0006] This alloy material, through the appropriate combination of C, Al, and Ti, ensures that it possesses both high thermal conductivity and excellent additive manufacturing performance, as well as high hardness. Simultaneously, by increasing the Ni content to replace Cr, while controlling the Ni content to avoid excessive levels, the alloy material maintains excellent thermal conductivity and rust resistance, while preventing a significant decrease in hardness. Furthermore, combined with appropriate subsequent heat treatment processes, the alloy material precipitates second phases such as Ni3 (AlTi) in conjunction with Al and Ti, significantly improving its strength. In addition, by controlling the reasonable addition amounts of Ni and Co, costs are reduced to some extent while ensuring excellent thermal conductivity, rust resistance, and high strength.

[0007] In some embodiments of this application, the alloy material comprises the following components by weight percentage: C 0.01%-0.05%, Ni 19%-30%, Co 15%-36%, Al 0.3%-2%, Ti 0.3%-2%, Si 0.02%-0.1%, N 0.05%-0.1%, and Fe 40%-65%.

[0008] In some embodiments of this application, the alloy material does not include Cr. By increasing the Ni element content to replace the Cr element, the alloy material is guaranteed to have both excellent thermal conductivity and rust resistance.

[0009] In some embodiments of this application, the weight percentage of Al and Ti includes Al+Ti ≤ 4wt%. The content of Al and Ti cannot be too high. If the weight percentage of Al+Ti exceeds 4%, it is easy to cause cracking of the additively manufactured parts during the additive manufacturing process, thereby reducing the additive manufacturing process performance of the alloy material.

[0010] In some embodiments of this application, the weight percentage of Ni and Co includes Ni+Co≤50wt%. This ensures that the alloy material has excellent thermal conductivity, rust resistance, and high strength, while also reducing costs to some extent.

[0011] In some embodiments of this application, the alloy material is a powder alloy material; the particle size of the alloy material is 15-75 μm. This facilitates subsequent additive manufacturing and ensures the excellent additive manufacturing process performance of the alloy material.

[0012] Secondly, embodiments of this application provide an additive manufacturing method, which includes the following steps:

[0013] S1: The components of the alloy material provided in the first aspect are batched and smelted according to weight percentage, and then cast, atomized and solidified to obtain powder alloy material;

[0014] S2: Additive manufacturing of powder alloy materials to print a predetermined mold.

[0015] In some embodiments of this application, in step S1, the melting temperature is 1580-1600℃, the casting temperature is 1450-1500℃, and the atomization pressure is 3-4MPa. The alloy material components are proportioned by weight percentage, melted at high temperature, and then atomized by high-temperature casting to obtain a powder alloy material with a particle size of 15-75μm.

[0016] In some embodiments of this application, in step S2, additive manufacturing employs laser powder spreading. The conditions for laser powder spreading include: scanning rate of 300-900 mm / s, laser power of 160-450 W, printing layer thickness of 60-100 μm, and overlap distance of 60-110 μm. High-quality molds without cracks are obtained by printing under suitable additive manufacturing conditions.

[0017] In some embodiments of this application, the additive manufacturing method further includes the following steps:

[0018] S3: The printed mold is heat-treated at 410-600℃ for 1-4 hours and then air-cooled to obtain the final heat-treated mold. By using a suitable heat treatment process, second phases such as Ni3 (AlTi) precipitate in the alloy material, which can significantly improve the strength of the alloy material.

[0019] Thirdly, embodiments of this application provide an application of the alloy material as provided in the first aspect in the preparation of injection molds.

[0020] In some embodiments of this application, the alloy material provided in the first aspect is used in the preparation of conformal cooling injection molds. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 The morphology diagram of the powder alloy material provided in Example 1;

[0023] Figure 2 Microstructure morphology of the mold provided in Example 1 during printing;

[0024] Figure 3 Microstructure morphology of the mold provided in Example 5 during printing;

[0025] Figure 4 Microstructure morphology of the mold in the heat-treated state provided in Example 5;

[0026] Figure 5 Microstructure morphology of the mold in the heat-treated state provided in Example 9;

[0027] Figure 6 Microstructure morphology of the mold in the heat-treated state provided in Example 10;

[0028] Figure 7 This is an external view of the conformal cooling injection mold provided in Example 10;

[0029] Figure 8 The appearance drawing of the conformal cooling injection mold provided for Comparative Example 1;

[0030] Figure 9 The appearance drawing of the conformal cooling injection mold provided for Comparative Example 2;

[0031] Figure 10 Microstructure diagram of the beryllium copper grafting interface provided for Experiment Example 2. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0033] This application provides an alloy material for additive manufacturing. The alloy material comprises the following components by weight percentage: C 0.005%-0.1%, Ni 12%-33%, Co 12%-38%, Al 0.05%-2%, Ti 0.05%-2%, Si 0.02%-0.2%, N 0.05%-0.2%, and Fe 36%-75%. Carbon can partially dissolve into the matrix of steel to provide solid solution strengthening, and it can also improve the hardenability and hardenability of steel, significantly increasing the strength of the material. However, if the carbon content is too high, it will reduce thermal conductivity and affect printability during additive manufacturing, easily causing cracking of the printed parts. Therefore, controlling the carbon content within the range of 0.005%-0.1% ensures the high thermal conductivity and excellent additive manufacturing performance of the alloy material. To ensure the alloy material possesses both excellent thermal conductivity and rust resistance, the Ni element content is increased to replace the Cr element. However, the Ni content cannot be too high, otherwise it easily forms a face-centered cubic (FCC) microstructure, significantly reducing the alloy's hardness. Therefore, the Ni content is controlled within the range of 19%-33% to ensure the alloy material maintains excellent thermal conductivity and rust resistance while avoiding a significant decrease in hardness. To improve the alloy's strength, appropriate amounts of strengthening elements such as Al and Ti are added, combined with suitable subsequent heat treatment processes to precipitate second phases such as Ni3 (AlTi). This significantly improves the alloy's strength, compensating for the insufficient hardness caused by low carbon content, and meeting the 46-48 HRC strength requirement for injection molds. Furthermore, to reduce costs while simultaneously ensuring excellent thermal conductivity, rust resistance, and high strength, the Co content in the alloy is reduced and controlled within the range of 12%-38%.

[0034] Further controlled alloy materials, by weight percentage, comprise the following components: C 0.01%-0.05%, Ni 19%-30%, Co 15%-36%, Al 0.3%-2%, Ti 0.3%-2%, Si 0.02%-0.1%, N 0.05%-0.1%, and Fe 40%-65%. Even more precisely, alloy materials, by weight percentage, comprise the following components: C 0.01%-0.05%, Ni 22%-28%, Co 15%-28%, Al 0.5%-2%, Ti 0.5%-2%, Si 0.02%-0.1%, N 0.05%-0.1%, and Fe 40%-60%.

[0035] As an example, the weight percentage of C in the alloy material includes, but is not limited to, 0.005%, 0.008%, 0.01%, 0.03%, 0.05%, 0.08%, and 0.1%. The weight percentage of Ni in the alloy material includes, but is not limited to, 12%, 14%, 16%, 19%, 21%, 22%, 24%, 27%, 28%, 30%, and 33%. The weight percentage of Co in the alloy material includes, but is not limited to, 12%, 15%, 18%, 20%, 22%, 24%, 26%, 28%, 30%, 32%, 36%, and 38%. The weight percentage of Al in the alloy material includes, but is not limited to, 0.05%, 0.08%, 0.1%, 0.3%, 0.5%, 0.8%, 1%, 1.5%, 1.8%, and 2%. The weight percentage of Ti in the alloy material includes, but is not limited to, 0.05%, 0.08%, 0.1%, 0.3%, 0.5%, 0.8%, 1%, 1.2%, 1.5%, 1.8%, and 2%. The weight percentage of Si in the alloy material includes, but is not limited to, 0.02%, 0.05%, 0.08%, 0.1%, and 0.2%. The weight percentage of N in the alloy material includes, but is not limited to, 0.05%, 0.08%, 0.1%, and 0.2%. To ensure that the alloy material possesses both excellent thermal conductivity and rust resistance, Ni content is increased to replace Cr. The alloy material does not contain Cr, or the weight percentage of Cr is ≤0.001%. On the one hand, reducing or removing Cr improves the thermal conductivity of the alloy material; however, excessively low Cr content will significantly reduce the rust resistance. Therefore, on the other hand, Ni content is increased to replace Cr to improve the rust resistance of the alloy material, thus ensuring that the alloy material possesses both excellent thermal conductivity and rust resistance. To prevent cracking of the additively manufactured parts and reduce the additive manufacturing performance of the alloy material during the additive manufacturing process, the weight percentage of Al and Ti (Al+Ti ≤ 4wt%) is controlled to improve the additive manufacturing performance of the alloy material. Furthermore, to reduce costs to some extent while ensuring excellent thermal conductivity, rust resistance, and high strength of the alloy material, the weight percentage of Ni and Co (Ni+Co ≤ 50wt%) is controlled. This ensures that the Ni content is not too high, guaranteeing both good thermal conductivity and rust resistance, as well as high hardness. Conversely, it ensures that the Co content is not too high, maintaining the hardness of the alloy material while reducing costs to some extent.

[0036] The additive manufacturing method for the aforementioned alloy materials is described below.

[0037] This additive manufacturing method includes the following steps: C, Ni, Co, Al, Ti, Si, N, and Fe are proportioned by weight and melted at 1580-1600℃, then cast at 1450-1500℃ and atomized and solidified at 3-4 MPa to obtain a powder alloy material with a particle size of 15-75 μm. The powder alloy material is then processed using laser powder spreading, with the following conditions: scanning rate 300-900 mm / s, laser power 160-450 W, printing layer thickness 60-100 μm, and overlap distance 60-110 μm, to print a predetermined mold. The printed predetermined mold is further heat-treated at 410-600℃ for 1-4 hours and air-cooled to obtain the final heat-treated mold. Through a suitable heat treatment process, second phases such as Ni3(AlTi) precipitate in the alloy material, which can significantly improve the strength of the alloy material.

[0038] The aforementioned alloy material can be used to manufacture injection molds. Furthermore, it can be used to manufacture conformal cooling injection molds. As an example, conformal cooling injection molds for parts such as electronic cigarettes can be manufactured.

[0039] The features and performance of this application will be further described in detail below with reference to the embodiments.

[0040] Example 1

[0041] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.02%, Ni 12%, Co 38%, Al 0.05%, Ti 0.05%, Si 0.02%, N 0.05%, and Fe 49.5%.

[0042] This embodiment also provides an additive manufacturing method, which includes the following steps:

[0043] S1: The components of the above alloy material are proportioned according to the weight percentage, melted at 1580-1600℃, and then cast at 1450-1500℃ and atomized and solidified at 3-4MPa to obtain powder alloy material. Figure 1 The morphology image of the powder alloy material provided in Example 1 is shown below. Figure 1 It can be seen that the powder alloy material is spherical powder with a particle size of 15-53μm;

[0044] S2: Additive manufacturing of powder alloy material using laser powder spreading method, wherein the scanning rate is 500mm / s, the laser power is 200w, the printing layer thickness is 50μm, the overlap distance is 110μm, and the pre-determined mold is printed. Figure 2 The microstructure morphology of the mold in the printed state provided in Example 1, from Figure 2 It can be seen that the alloy density of the mold exceeds 99.9%.

[0045] Example 2

[0046] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.01%, Ni 27%, Co 32%, Al 0.05%, Ti 0.05%, Si 0.02%, N 0.05%, and Fe 40.5%.

[0047] In this embodiment, a pre-printed mold is prepared according to the additive manufacturing method provided in Embodiment 1.

[0048] Example 3

[0049] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.05%, Ni 12%, Co 28%, Al 0.05%, Ti 0.05%, Si 0.02%, N 0.05%, and Fe 59.5%.

[0050] In this embodiment, a pre-printed mold is prepared according to the additive manufacturing method provided in Embodiment 1.

[0051] Example 4

[0052] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.01%, Ni 12%, Co 28%, Al 0.05%, Ti 0.5%, Si 0.02%, N 0.05%, and Fe 59%.

[0053] This embodiment also provides an additive manufacturing method, which includes the following steps:

[0054] S1: The components of the above alloy material are proportioned according to the weight percentage, melted at 1580-1600℃, and then cast at 1450-1500℃ and atomized and solidified at 3-4MPa to obtain powder alloy material.

[0055] S2: Additive manufacturing of powder alloy material using laser powder spreading method, wherein the scanning rate is 500mm / s, the laser power is 360w, the printing layer thickness is 80μm, the overlap distance is 100μm, and the pre-determined mold is printed.

[0056] S3: Heat-treat the printed mold at 550℃ for 1-4 hours, then air-cool it to obtain the final heat-treated mold.

[0057] Example 5

[0058] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.01%, Ni 12%, Co 28%, Al 0.05%, Ti 1.5%, Si 0.02%, N 0.05%, and Fe 58%.

[0059] This embodiment also provides an additive manufacturing method, which includes the following steps:

[0060] S1: The components of the above alloy material are proportioned according to the weight percentage, melted at 1580-1600℃, and then cast at 1450-1500℃ and atomized and solidified at 3-4MPa to obtain powder alloy material.

[0061] S2: Additive manufacturing of powder alloy material using laser powder spreading method, wherein the scanning rate is 500mm / s, the laser power is 200w, the printing layer thickness is 50μm, the overlap distance is 110μm, and a predetermined mold is printed. Figure 3 The image shows the microstructure of the mold in the printed state provided in Example 5. Figure 3 (b) is Figure 3 (a) Enlarged view of the area highlighted in the box, from Figure 3 It can be seen that the printed mold provided in Example 5 exhibits a peritectic microstructure;

[0062] S3: Heat-treat the printed mold at 450℃ for 1-4 hours, then air-cool it to obtain the final heat-treated mold. Figure 4 The image shows the microstructure of the mold in the heat-treated state provided in Example 5. Figure 4 (j) is Figure 4 (i) Enlarged view of the selected area, from Figure 4 It can be seen that the heat-treated mold provided in Example 5 exhibits fine precipitates.

[0063] Example 6

[0064] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.01%, Ni 12%, Co 28%, Al 0.05%, Ti 2%, Si 0.02%, N 0.05%, and Fe 57%.

[0065] This embodiment also provides an additive manufacturing method, which includes the following steps:

[0066] S1: The components of the above alloy material are proportioned according to the weight percentage, melted at 1580-1600℃, and then cast at 1450-1500℃ and atomized and solidified at 3-4MPa to obtain powder alloy material.

[0067] S2: Additive manufacturing of powder alloy material using laser powder spreading method, wherein the scanning rate is 500mm / s, the laser power is 200w, the printing layer thickness is 50μm, the overlap distance is 110μm, and a predetermined mold is printed.

[0068] S3: Heat-treat the printed mold at 580℃ for 1-4 hours, then air-cool it to obtain the final heat-treated mold.

[0069] Example 7

[0070] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.01%, Ni 16%, Co 24%, Al 0.05%, Ti 0.05%, Si 0.1%, N 0.05%, and Fe 59.5%.

[0071] In this embodiment, a pre-printed mold is prepared according to the additive manufacturing method provided in Embodiment 1.

[0072] Example 8

[0073] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.01%, Ni 22%, Co 18%, Al 0.05%, Ti 0.05%, Si 0.1%, N 0.05%, and Fe 59.5%.

[0074] In this embodiment, a pre-printed mold is prepared according to the additive manufacturing method provided in Embodiment 1.

[0075] Example 9

[0076] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.01%, Ni 22%, Co 18%, Al 0.5%, Ti 0.05%, Si 0.02%, N 0.05%, and Fe 58.5%.

[0077] This embodiment also provides an additive manufacturing method, which includes the following steps:

[0078] S1: The components of the above alloy material are proportioned according to the weight percentage, melted at 1580-1600℃, and then cast at 1450-1500℃ and atomized and solidified at 3-4MPa to obtain powder alloy material.

[0079] S2: Additive manufacturing of powder alloy material using laser powder spreading method, wherein the scanning rate is 500mm / s, the laser power is 200w, the printing layer thickness is 50μm, the overlap distance is 110μm, and a predetermined mold is printed.

[0080] S3: Heat-treat the printed mold at 410℃ for 1-4 hours, then air-cool it to obtain the final heat-treated mold. Figure 5 The image shows the microstructure of the mold in the heat-treated state provided in Example 9. Figure 5 (b) is Figure 5 (a) Enlarged view of the area highlighted in the box, from Figure 5 It can be seen that the heat-treated mold provided in Example 9 exhibits fine precipitates.

[0081] Example 10

[0082] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.01%, Ni 22%, Co 18%, Al 1.5%, Ti 0.05%, Si 0.02%, N 0.05%, and Fe 56.5%.

[0083] This embodiment also provides an additive manufacturing method, which includes the following steps:

[0084] S1: The components of the above alloy material are proportioned according to the weight percentage, melted at 1580-1600℃, and then cast at 1450-1500℃ and atomized and solidified at 3-4MPa to obtain powder alloy material.

[0085] S2: Additive manufacturing of powder alloy material using laser powder spreading method, wherein the scanning rate is 500mm / s, the laser power is 200w, the printing layer thickness is 50μm, the overlap distance is 110μm, and a pre-designed conformal cooling injection mold is printed.

[0086] S3: Heat-treat the printed mold at 430℃ for 1-4 hours, then air-cool it to obtain the final heat-treated mold. Figure 6 This is a microstructure image of the mold in the heat-treated state provided in Example 10. Figure 6 (b) is Figure 6 (a) Enlarged view of the area highlighted in the box, from Figure 6 It can be seen that the heat-treated mold provided in Example 10 exhibits coarsened precipitates. Figure 7 An external view of the conformal cooling injection mold provided in Example 10.

[0087] Example 11

[0088] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.01%, Ni 22%, Co 18%, Al 2%, Ti 0.05%, Si 0.02%, N 0.05%, and Fe 55.5%.

[0089] This embodiment also provides an additive manufacturing method, which includes the following steps:

[0090] S1: The components of the above alloy material are proportioned according to the weight percentage, melted at 1580-1600℃, and then cast at 1450-1500℃ and atomized and solidified at 3-4MPa to obtain powder alloy material.

[0091] S2: Additive manufacturing of powder alloy material using laser powder spreading method, wherein the scanning rate is 500mm / s, the laser power is 200w, the printing layer thickness is 50μm, the overlap distance is 110μm, and a predetermined mold is printed.

[0092] S3: Heat-treat the printed mold at 530℃ for 1-4 hours, then air-cool it to obtain the final heat-treated mold.

[0093] Example 12

[0094] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.01%, Ni 28%, Co 12%, Al 0.05%, Ti 0.05%, Si 0.02%, N 0.05%, and Fe 59.5%.

[0095] This embodiment also provides an additive manufacturing method, which includes the following steps:

[0096] S1: The components of the above alloy material are proportioned according to the weight percentage, melted at 1580-1600℃, and then cast at 1450-1500℃ and atomized and solidified at 3-4MPa to obtain powder alloy material.

[0097] S2: Additive manufacturing of powder alloy material using laser powder spreading method, wherein the scanning rate is 300mm / s, the laser power is 450w, the printing layer thickness is 100μm, the overlap distance is 90μm, and the pre-determined mold is printed.

[0098] Example 13

[0099] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.01%, Ni 21%, Co 15%, Al 0.05%, Ti 0.05%, Si 0.02%, N 0.05%, and Fe 63.5%.

[0100] In this embodiment, a pre-printed mold is prepared according to the additive manufacturing method provided in Embodiment 1.

[0101] Example 14

[0102] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.03%, Ni 16%, Co 15%, Al 0.05%, Ti 0.05%, Si 0.02%, N 0.05%, and Fe 68.8%.

[0103] In this embodiment, a pre-printed mold is prepared according to the additive manufacturing method provided in Embodiment 1.

[0104] Comparative Example 1

[0105] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.2%, Ni 12%, Co 28%, Al 0.05%, Ti 0.05%, Si 0.02%, N 0.05%, and Fe 59.6%.

[0106] In this embodiment, a pre-printed mold is prepared according to the additive manufacturing method provided in Embodiment 1. Figure 8 The appearance drawing of the conformal cooling injection mold provided in Comparative Example 1 is from... Figure 8 It can be seen that microcracks appeared at the variable cross-section location of the conformal cooling injection mold provided in Comparative Example 1.

[0107] Comparative Example 2

[0108] This embodiment provides an alloy material for additive manufacturing, which comprises the following components by weight percentage: C 0.01%, Ni 22%, Co 18%, Al 2.5%, Ti 2.5%, Si 0.02%, N 0.05%, and Fe 54.9%.

[0109] This comparative example shows the preparation of a pre-printed mold using the additive manufacturing method provided in Example 1. Figure 9 For the conformal cooling injection mold appearance drawing provided in Comparative Example 2, from Figure 9 It can be seen that microcracks appeared at the variable cross-section position of the conformal cooling injection mold provided in Comparative Example 2. When the Al+Ti content is too high, it will cause cracking of the additive manufacturing printed parts and reduce the additive manufacturing process performance of the alloy material.

[0110] The additive manufacturing alloy materials provided in Examples 2-14 and Comparative Examples 1-2 are basically the same as those in Example 1, except that the weight percentages of each component are different, as shown in Table 1.

[0111] Table 1. Composition of Alloy Materials for Additive Manufacturing

[0112] C(％) Ni (%) Co (%) Al(％) Ti (%) Si (%) N(％) Fe (%) Example 1 0.02 12 38 0.05 0.05 0.02 0.05 49.5 Example 2 0.01 27 32 0.05 0.05 0.02 0.05 40.5 Example 3 0.05 12 28 0.05 0.05 0.02 0.05 59.5 Example 4 0.01 12 28 0.05 0.5 0.02 0.05 59 Example 5 0.01 12 28 0.05 1.5 0.02 0.05 58 Example 6 0.01 12 28 0.05 2 0.02 0.05 57 Example 7 0.01 16 24 0.05 0.05 0.1 0.05 59.5 Example 8 0.01 22 18 0.05 0.05 0.1 0.05 59.5 Example 9 0.01 22 18 0.5 0.05 0.02 0.05 58.5 Example 10 0.01 22 18 1.5 0.05 0.02 0.05 56.5 Example 11 0.01 22 18 2 0.05 0.02 0.05 55.5 Example 12 0.01 28 12 0.05 0.05 0.02 0.05 59.5 Example 13 0.01 21 15 0.05 0.05 0.02 0.05 63.5 Example 14 0.03 16 15 0.05 0.05 0.02 0.05 68.8 Comparative Example 1 0.2 12 28 0.05 0.05 0.02 0.05 59.6 Comparative Example 2 0.01 22 18 2.5 2.5 0.02 0.05 54.9

[0113] The additive manufacturing methods provided in Examples 2-3, 7-8, 13-14 and Comparative Examples 1-2 are exactly the same as those in Example 1; the additive manufacturing methods provided in Examples 4-6 and 9-12 are basically the same as those in Example 1, except that the process parameters and processing methods are different, as shown in Table 2.

[0114] Table 2 Additive Manufacturing Methods

[0115]

[0116] Experimental Example 1

[0117] This test example examines the Vickers hardness and thermal conductivity of the molds provided in Examples 1-14 and Comparative Example 1.

[0118] The samples were tested using a Vickers hardness tester. Before the hardness test, the sample surface was rough-ground to remove the surface oxide layer. To ensure the repeatability of the results, five hardness values ​​were tested for each sample and the average value was taken.

[0119] The thermal conductivity was tested according to GB / T 22588-2008, specifically for the thermal diffusivity, specific heat capacity, and density of the sample materials. Thermal conductivity = thermal diffusivity × specific heat capacity × density. The results are shown in Table 3.

[0120] Table 3 Vickers Hardness and Thermal Conductivity

[0121]

[0122]

[0123] Table 3 shows that, comparing the results of Examples 2 and 14, the hardness of the alloy material decreases significantly when the Ni content is too high. This is because a high Ni content easily leads to the formation of a face-centered cubic (FCC) microstructure, resulting in a substantial decrease in the alloy material's hardness. Comparing the results of Examples 4-6 shows that the hardness of the alloy material increases with increasing Ti content. Comparing the results of Examples 9-11 shows that the hardness of the alloy material also increases with increasing Al content. This is because Al and Ti are strengthening elements, and combined with appropriate heat treatment processes, they can precipitate second phases such as Ni3(AlTi), thereby significantly improving the strength of the alloy material. Comparing the results of Examples 2 and 12 shows that when the scanning rate and overlap distance in additive manufacturing decrease, and the laser power and printing layer thickness increase, the density of the alloy material remains unchanged, without affecting the material's hardness and thermal conductivity. Comparing the results of Examples 4 and 9 shows that increasing the heat treatment temperature of the material increases both the hardness and thermal conductivity of the alloy.

[0124] Experimental Example 2

[0125] In this experimental example, the powder alloy material provided in Example 11 was grafted with beryllium copper material, and then a predetermined mold was printed according to the additive manufacturing method provided in Example 11. The microstructure of the grafting interface of the mold is as follows: Figure 10 As shown.

[0126] Depend on Figure 10 It can be seen that the microstructure of the grafting interface after beryllium copper and powder alloy material is free of cracks and defects; this indicates that the alloy material provided by the present invention has excellent additive manufacturing process performance and can be matched with other materials for printing.

[0127] The embodiments described above are some, but not all, of the embodiments of this application. The detailed description of the embodiments of this application is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

Claims

1. An additive manufacturing method, characterized in that, The additive manufacturing method includes the following steps: S1: The alloy material components are batched and smelted according to weight percentage, and then cast, atomized, and solidified. The alloy material, by weight percentage, consists of the following components: C 0.005%-0.1%, Ni 12%-33%, Co 12%-38%, Al 0.05%-2%, Ti 0.05%-2%, Si 0.02%-0.2%, N 0.05%-0.2%, and Fe 36%-75%, to obtain a powder alloy material. S2: The powder alloy material is additively manufactured and printed into a predetermined mold; S3: Heat-treat the printed mold at 410-600℃ for 1-4 hours, then air-cool it to obtain the final heat-treated mold.

2. The additive manufacturing method according to claim 1, characterized in that, The alloy material, by weight percentage, consists of the following components: C 0.01%-0.05%, Ni 19%-30%, Co 15%-36%, Al 0.3%-2%, Ti 0.3%-2%, Si 0.02%-0.1%, N 0.05%-0.1%, and Fe 40%-65%.

3. The additive manufacturing method according to claim 1 or 2, characterized in that, The weight percentages of Al and Ti satisfy Al+Ti≤4wt%.

4. The additive manufacturing method according to claim 3, characterized in that, The weight percentages of Ni and Co satisfy Ni+Co≤50wt%.

5. The additive manufacturing method according to claim 1 or 2, characterized in that, The alloy material is a powder alloy material; the particle size of the alloy material is 15-75μm.

6. The additive manufacturing method according to claim 1, characterized in that, In step S1, the melting temperature is 1580-1600℃, the casting temperature is 1450-1500℃, and the atomization pressure is 3-4MPa.

7. The additive manufacturing method according to claim 1, characterized in that, In step S2, additive manufacturing is performed using laser powder spreading. The conditions for laser powder spreading include: scanning rate of 300-900 mm / s, laser power of 160-450 W, printing layer thickness of 60-100 μm, and overlap distance of 60-110 μm.

8. The application of the additive manufacturing method as described in any one of claims 1-7 in the preparation of injection molds, characterized in that, Application in the preparation of conformal cooling injection molds.

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