Laser printing method of stainless steel powder, three-dimensional member and heat treatment method thereof

Abstract

This application proposes a laser printing method for stainless steel powder, comprising: depositing a stainless steel powder layer with a thickness of 0.05-0.07 mm on a substrate in a forming cavity; selectively scanning with an infrared laser beam according to a predetermined scanning strategy under an inert gas protective atmosphere, based on 3D model slicing data, causing the powder layer to melt and solidify to form a cladding layer; repeating the above steps until a 3D component is obtained. The scanning strategies include: (1) laser power 200-250 W, scanning spacing 0.08-0.11 mm, scanning speed 700-900 mm / s; (2) laser power 250-300 W, scanning spacing 0.08-0.11 mm, scanning speed 900-1100 mm / s; (3) laser power 300-400 W, scanning spacing 0.07-0.09 mm, scanning speed 800-1000 mm / s. Additionally, this application also provides a stainless steel 3D component and its heat treatment method.

Description

Technical Field

[0001] This application relates to the field of additive manufacturing, and more particularly to a laser printing method for stainless steel powder, a three-dimensional component, and a heat treatment method thereof. Background Technology

[0002] Traditional S-03 stainless steel (grade 022Cr12Ni10MoTi) relies on forging or casting processes for manufacturing. Forging is constrained by molds and cannot form thin-walled curved surfaces and internal cavity structures. Casting is prone to internal defects due to insufficient melt fluidity. As a result, it has inherent limitations in forming complex three-dimensional components and it is difficult to achieve fine structural processing. Summary of the Invention

[0003] In view of this, this application provides a laser printing method for stainless steel powder to achieve efficient and dense forming of S-03 stainless steel powder under the condition of a large powder layer thickness, while taking into account printing efficiency and component density.

[0004] In addition, it is necessary to provide a three-dimensional component and its heat treatment method.

[0005] A laser printing method for stainless steel powder includes the following steps: depositing a layer of stainless steel powder with a thickness of 0.05-0.07 mm on a substrate or a previous solidified layer within a forming cavity. The stainless steel powder layer, by mass fraction, comprises: carbon ≤0.03%, silicon ≤0.15%, manganese ≤0.15%, phosphorus ≤0.008%, sulfur ≤0.006%, chromium 11.5%~12.5%, nickel 9.0%~10.3%, molybdenum 0.5%~0.8%, titanium 0.15%~0.25%, aluminum ≤0.2%, and the balance iron; under an inert gas protective atmosphere, controlling an infrared laser beam to selectively scan the stainless steel powder layer according to a predetermined scanning strategy based on preset three-dimensional model slice data. A stainless steel powder layer is irradiated and melted to form a cladding layer; the above steps are repeated to print layer by layer until the three-dimensional component is completed, wherein the scanning strategy includes any one of the following parameter packages: (1) infrared laser power 200-250W, scanning spacing 0.08-0.11mm, scanning speed 700-900mm / s; (2) infrared laser power 250-300W, scanning spacing 0.08-0.11mm, scanning speed 900-1100mm / s; (3) infrared laser power 300-400W, scanning spacing 0.07-0.09mm, scanning speed 800-1000mm / s.

[0006] In some possible implementations, the predetermined scanning strategy further includes performing an S-shaped reciprocating filling scan in the internal region of the two-dimensional cross-section corresponding to the three-dimensional model slice data.

[0007] In some possible implementations, the predetermined scanning strategy further includes: rotating the fill scanning direction of each layer by 67° relative to the previous layer, and performing a contour scan of the two-dimensional cross-section after completing the fill scan of the inner region.

[0008] In some possible implementations, the parameter package includes: a scanning interval of 0.09 mm, a laser power of 250 W, a scanning speed of 900 mm / s, and an energy density of 51.44 J / mm². 3 .

[0009] In some possible implementations, the parameter package includes: a scanning spacing of 0.09 mm, a laser power of 350 W, a scanning speed of 900 mm / s, and an energy density of 72.02 J / mm². 3 .

[0010] In some possible implementations, the parameter package includes: a scanning interval of 0.1 mm, a laser power of 300 W, a scanning speed of 1050 mm / s, and an energy density of 47.62 J / mm². 3 .

[0011] In some possible implementations, the thickness of the stainless steel powder layer is 0.06 mm.

[0012] In some possible implementations, the inert gas is argon or nitrogen, and the wavelength of the infrared laser beam is 1064 nm.

[0013] A stainless steel three-dimensional component prepared by the above-mentioned laser printing method, wherein the density of the three-dimensional component is not less than 99.991%.

[0014] A heat treatment method for a three-dimensional component as described above includes the following steps: heating the three-dimensional component to 600℃-900℃, holding it at that temperature for 1 hour-5 hours, and then air quenching; heating the three-dimensional component to 600℃-900℃, holding it at that temperature for 1 hour-5 hours, and then air quenching; and heating the three-dimensional component to 400℃-700℃, holding it at that temperature for 2 hours-5 hours, and then air cooling.

[0015] This application utilizes S-03 stainless steel powder with a specific chemical composition ratio and particle size range (1553 μm), and combines optimized large-layer-thickness powder spreading (0.05-0.07 mm) with multiple sets of infrared laser scanning parameter packages under an inert atmosphere to significantly improve forming efficiency while maintaining a high density of ≥99.991%. The different parameter packages can respectively meet the forming requirements of low internal stress, high efficiency, and high density, effectively solving the technical problems in the prior art, such as the difficulty of large-layer-thickness printing due to the low infrared absorption rate of S-03 stainless steel, the low efficiency of traditional SLM processes, and the susceptibility of internal defects. It also gives the components greater manufacturing freedom and performance consistency, broadening its applicability in complex structures and high-performance applications. Attached Figure Description

[0016] Figure 1 A flowchart of a laser printing method for stainless steel powder provided in an embodiment of this application.

[0017] Figure 2 A flowchart of a heat treatment method for a stainless steel three-dimensional component provided in an embodiment of this application. Detailed Implementation

[0018] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0019] It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or may also exist in an intervening component. When a component is considered to be "set on" another component, it can be directly set on the other component or may also exist in an intervening component.

[0020] In this application, the laser printing equipment includes a laser generator, an optical system, a forming cavity, a powder spreading device, an inert gas protection system, and a control system. The working principle of the laser printing equipment is as follows: the control system controls the laser generator to generate a laser beam with specific power and wavelength according to the preset three-dimensional model slice data. After being focused by the optical system, the laser beam selectively scans and melts the spread metal powder layer in the forming cavity protected by inert gas, causing the powder to melt and solidify and be stacked layer by layer to form a three-dimensional solid component.

[0021] In this application, the heat treatment equipment includes a heat treatment furnace, a temperature control system, a protective atmosphere system, and a cooling system. The working principle of the heat treatment equipment is as follows: the temperature control system precisely regulates the temperature inside the heat treatment furnace and uniformly heats the printed three-dimensional component according to predetermined process conditions (such as temperature and holding time); the protective atmosphere system ensures a stable environment inside the furnace and prevents oxidation; the cooling system gradually reduces the component temperature according to a preset cooling method, such as furnace cooling or air cooling, to obtain the target microstructure and properties.

[0022] Please see Figure 1 This application provides a laser printing method for stainless steel powder, enabling the high-efficiency manufacturing of three-dimensional stainless steel components, which possess advantages such as low internal stress and high density. The laser printing method includes the following steps: S1: A layer of stainless steel powder with a thickness of 0.05-0.07 mm is laid on the substrate or the previous solidified layer in the molding cavity. Preferably, the thickness of the stainless steel powder layer is 0.06 mm.

[0023] In this embodiment, the stainless steel powder layer in step S1 comprises the following components by mass fraction: carbon ≤0.03%, silicon ≤0.15%, manganese ≤0.15%, phosphorus ≤0.008%, sulfur ≤0.006%, chromium 11.5%~12.5%, nickel 9.0%~10.3%, molybdenum 0.5%~0.8%, titanium 0.15%~0.25%, aluminum ≤0.2%, and the balance iron. The stainless steel powder is grade 022Cr12Ni10MoTi, prepared by gas atomization, and has a regular spherical shape with a particle size range of 15-53 μm.

[0024] S2: Under an inert gas protective atmosphere, based on preset three-dimensional model slice data, an infrared laser beam is controlled to selectively scan the stainless steel powder layer according to a predetermined scanning strategy, causing the scanned stainless steel powder layer to melt and solidify, forming a cladding layer. The scanning strategy includes any one of the following parameter packages: (1) The infrared laser power is 200-250W, the scanning distance is 0.08-0.11mm, and the scanning speed is 700-900mm / s. During the printing process with parameter package (1), the laser input energy is relatively low, and the printing density can be maintained. It is suitable for printing stainless steel three-dimensional components with high requirements for deformation control. The low energy input introduces less heat accumulation and thermal cycling, which can reduce the internal stress of stainless steel three-dimensional components, thereby reducing the deformation risk of internal stress in stainless steel three-dimensional components. Preferably, the scanning distance is 0.09mm, the laser power is 250W, the scanning speed is 900mm / s, and the energy density is 51.44J / mm. 3 .

[0025] (2) The infrared laser power is 250-300W, the scanning distance is 0.08-0.11mm, and the scanning speed is 900-1100mm / s. In the printing process of parameter package (2), the high laser power, large scanning distance, and high scanning speed result in high energy input per unit time, which is suitable for manufacturing stainless steel three-dimensional components with simple shapes and stable structures, ensuring high manufacturing efficiency per unit time. Preferably, the scanning distance is 0.09mm, the laser power is 350W, the scanning speed is 900mm / s, and the energy density is 72.02J / mm. 3 .

[0026] (3) Infrared laser power 300-400W, scanning spacing 0.07-0.09mm, scanning speed 800-1000mm / s. After printing with parameter package (3), the printed stainless steel three-dimensional component has the highest density and few defects. Preferably, the scanning spacing is 0.1mm, the laser power is 300W, the scanning speed is 1050mm / s, and the energy density is 47.62J / mm. 3 .

[0027] In this context, infrared laser power P refers to the energy of the infrared laser beam output by the laser generator per unit time, measured in watts (W), and is used to characterize the laser's heating capability on a stainless steel powder layer. Scanning distance h is the distance between two adjacent scanning paths, measured in mm. Scanning speed refers to the speed at which the laser beam moves across the powder layer surface. Energy density refers to the energy input by the laser per unit volume of powder material, and its calculation formula is: In the formula, Ev is the volume energy density (J / mm³), P is the laser power (W), v is the scanning speed (mm / s), h is the scanning spacing (mm), and t is the thickness of a single layer of powder (mm). The energy density is used to comprehensively evaluate the influence of parameters such as laser power, scanning speed, scanning spacing, and layer thickness on the degree of powder melting.

[0028] In this embodiment, the predetermined scanning strategy in step S2 includes: performing an S-shaped reciprocating filling scan in the internal region of the two-dimensional cross-section corresponding to the three-dimensional model slice data. The S-shaped reciprocating filling refers to the continuous "S" or "zigzag" zigzag motion of the laser beam as it continuously scans the internal filling region of each layer along a single direction. Specifically, after the laser beam scans along a parallel line to the end of the line segment, it does not turn off the laser or raise the laser head. Instead, it directly scans the next parallel line at the adjacent scanning interval in a direction completely opposite to the previous line segment. This alternating direction is repeated until the internal region of the layer is filled.

[0029] The predetermined scanning strategy in step S2 also includes: rotating the scanning direction of each layer by 67° relative to the previous layer to reduce residual stress; and performing a scan of the two-dimensional cross-sectional profile after completing the internal region filling scan to improve the surface accuracy and density of the component.

[0030] S3: Completely melt and solidify the stainless steel powder in the scanned area to form a cladding layer.

[0031] In this embodiment, in step S3, the stainless steel powder that has been scanned and melted by the laser beam rapidly solidifies into a uniform and dense cladding layer. This process is carried out under the protection of an inert gas, thereby suppressing oxidation and splash contamination, ensuring that the internal structure of the stainless steel three-dimensional component is uniform and fine, and obtaining high density.

[0032] S4: Repeat steps S1 to S3, printing layer by layer until the stainless steel three-dimensional component is completed. The density of the stainless steel three-dimensional component is not less than 99.991%. Density refers to the volume ratio of the component excluding voids. High density means higher component strength, better electrical and thermal conductivity.

[0033] Compared with existing technologies, the laser printing method for stainless steel powder provided in this application has the following advantages: (i) This application selects S-03 stainless steel powder with a specific chemical composition ratio and combines it with an optimized large layer thickness powder spreading (0.05~0.07mm), S-shaped reciprocating filling scanning and interlayer rotation of 67° scanning strategy, so that the larger layer thickness powder can be fully melted and uniformly solidified under infrared laser irradiation. This significantly improves the single layer printing thickness and printing efficiency while ensuring the forming accuracy, and overcomes the problem of low efficiency caused by the limited layer thickness (usually less than 20μm) in the prior art.

[0034] (ii) This application establishes an energy density parameter system consisting of laser power, scanning speed, scanning spacing and layer thickness, and selects three optimal parameter packages with low stress, high efficiency and high density in multiple parameter tests, so that the density of the prepared component can reach more than 99.991% and the porosity is less than 0.004%, thereby significantly improving the forming problem of S-03 stainless steel with low absorption rate in the infrared band and easy to generate internal defects, and realizing the comprehensive optimization of strength, plasticity and manufacturing efficiency.

[0035] Please see Figure 2 An embodiment of this application also provides a heat treatment method for a three-dimensional stainless steel component, comprising the following steps: S5: Place the stainless steel three-dimensional component from step S4 into a heat treatment device, set the heat treatment temperature to 600℃-900℃, the holding time to 1 hour-5 hours, and then air quench and cool to room temperature.

[0036] S6: Reheat the stainless steel three-dimensional component from step S5 to 600℃-900℃, hold for 1 hour-5 hours, and then air quench to room temperature.

[0037] S7: Reheat the stainless steel three-dimensional component from step S6 to 400℃-700℃ and hold for 2-5 hours, then cool to room temperature. This achieves high electrical and thermal conductivity and moderate mechanical properties, as shown in Table 1.

[0038] Table 1: Mechanical properties of stainless steel three-dimensional components This application designs a phased heat treatment process, namely, two gas quenchings at 600℃-900℃ and one air cooling treatment at 400℃-700℃, which effectively reduces the residual stress of stainless steel three-dimensional components, improves the uniformity of the microstructure, and enhances the elongation and impact toughness of stainless steel three-dimensional components.

[0039] The present application will be described in detail below with reference to representative embodiments to help understand the spirit and essence of the present application, but without limiting the scope of the present application in any way.

[0040] Laser Printing: First, prepare stainless steel powder (S-03 stainless steel powder, grade: 022Cr12Ni10MoTi), and set the printing layer thickness of the laser printing equipment to 60μm. Preheat the substrate in the forming cavity to 100℃. Then, using different parameter packages of laser power (250-350W), scanning speed (600-900mm / s), and scanning spacing (0.07-0.10mm), selective laser melting (SLM) printing is performed on the powder to obtain multiple stainless steel three-dimensional component samples. Next, the printed samples are subjected to metallographic polishing, the microstructure is observed, and the porosity is measured to evaluate the sample density and select the optimal parameter package. See Table 2 for specific parameter packages and porosities.

[0041] Table 2. Laser Printing Parameter Packages and Porosity In Table 2, porosity refers to the percentage of the void volume inside the component to the total volume of the component within the microstructure observation range, and is used to evaluate the compactness of the component; the maximum defect size refers to the characteristic size of the largest single hole or inclusion inside the component measured under microscopic observation, in micrometers (μm), and this parameter can directly reflect the severity of defects inside the component.

[0042] It can be seen that for parameter package (1): infrared laser power 200-250W, scanning spacing 0.08-0.11mm, scanning speed 700-900mm / s; for example, sample No. 2 (power 250W, spacing 0.09mm, scanning speed 900mm / s, energy density 51.44J / mm³) obtained an ultra-low porosity of 0.006% and a small maximum defect size of 28.0μm while maintaining a low energy input, thus achieving a forming effect that balances high density and low residual stress.

[0043] For parameter package (2): infrared laser power 250-300W, scanning spacing 0.08-0.11mm, scanning speed 900-1100mm / s; for example, sample No. 19 (power 300W, spacing 0.1mm, scanning speed 1050mm / s, energy density 47.62J / mm³) still maintains a low porosity of 0.009% and a maximum defect size of 29.6μm under the conditions of larger scanning spacing and higher scanning speed, achieving a balance between high forming efficiency and good density; For parameter package (3): infrared laser power 300-400W, scanning spacing 0.07-0.09mm, scanning speed 800-1000mm / s; for example, sample No. 10 (power 350W, spacing 0.09mm, scanning speed 900mm / s, energy density 72.02J / mm³) achieved the lowest porosity of only 0.003% and the smallest defect size of 17.3μm under high power conditions, with the highest density and the best forming quality.

[0044] Heat treatment: The stainless steel three-dimensional components processed according to parameter packages (1), (2), and (3) are placed in a heat treatment equipment and subjected to the following heating and cooling scheme: First, the stainless steel three-dimensional components are placed in the heat treatment equipment, the heat treatment temperature is set to 600℃-900℃, the holding time is 1 hour-5 hours, and then air-quenched to room temperature. Next, the stainless steel three-dimensional components are reheated to 600℃-900℃, the holding time is 1 hour-5 hours, and then air-quenched to room temperature. Finally, the stainless steel three-dimensional components from step S6 are reheated to 400℃-700℃, the holding time is 2 hours-5 hours, and then air-cooled to room temperature to complete the heat treatment.

[0045] Room temperature tensile test: After the heat treatment described above, the stainless steel three-dimensional components obtained by printing the parameter packages (1) to (3) were tested for tensile and room temperature impact properties at room temperature in accordance with GB / T228.1-2021 (Metallic materials, tensile testing - Part 1: Room temperature test method). The results are shown in Table 3. Table 3: Room Temperature Tensile Test Results of Examples Among them, the Z direction of the specimen refers to the tensile direction of the specimen being parallel to the building direction (forming layer stacking direction) of the component during the laser printing process, that is, the direction perpendicular to the powder-laying plane of each layer; the XY direction of the specimen refers to the tensile direction of the specimen being parallel to the single-layer powder-laying plane of the component during the laser printing process, that is, the tensile test is performed in the horizontal direction.

[0046] As shown in Table 3, under the printing conditions of parameter package (1), the tensile strength of the stainless steel three-dimensional component in the Z direction can reach 984 MPa and the elongation is 18%, while the elongation in the XY direction can reach 1001 MPa and the elongation is 20%. Thus, while maintaining high strength, it achieves good plasticity, indicating that the parameter package effectively reduces the residual stress of the component under low energy input conditions and is suitable for low internal stress printing with high requirements for forming deformation control. Under the printing conditions of parameter package (2), the tensile strength of stainless steel three-dimensional components in the Z direction is 959~968MPa and the elongation is 14.5%~15%, while the XY direction can reach 1008~1012MPa and the elongation is 14.5%~16.5%, thereby achieving higher printing efficiency per unit time while ensuring strength. It is suitable for high-efficiency printing of large batches of simple shapes and stable structures. Under the printing conditions of parameter package (3), the tensile strength of stainless steel three-dimensional components in the Z direction is 943~954MPa and the elongation is 14%~15%, while the XY direction can reach 9921024MPa and the elongation is 15.5%~16.5%, thereby achieving extremely low porosity and minimum defect size, which is suitable for high-density printing with extremely high requirements for structural compactness.

[0047] Room temperature impact test: The stainless steel three-dimensional components obtained by printing parameter packages (1) to (3) were subjected to impact performance testing (U-notch) at room temperature according to GB / T229-2020 (Metallic materials - Charpy pendulum impact test method). The results are shown in Table 4. Table 4: Results of Room Temperature Impact Testing (U-notch) in Examples According to the requirements of standard GB / T229-2020, the impact energy is ≥108KU2(J). It can be seen that the stainless steel three-dimensional components obtained according to parameter packages (1) to (3) are significantly higher than the standard requirements after the above heat treatment. Among them, the impact energy of parameter package (1) is 176.0-187.0KU2(J), which shows excellent toughness and impact resistance; the impact energy of parameter package (2) is 132.5-133.0KU2(J), which maintains the advantage of high-efficiency printing while still having good toughness; the impact energy of parameter package (3) is 159.0-172.0KU2(J), which ensures high density while taking into account high impact resistance, reflecting the balance and optimization effect of the heat treatment system of this application between strength and toughness.

[0048] Comparative Example 1: The stainless steel three-dimensional component was heat-treated according to GJB7960-2012 (Specification for Hot-Rolled (Forged) Stainless Steel Bars for Rockets), specifically including the following steps: solution treatment: holding at 750℃±10℃ for 1 hour, followed by air cooling or water quenching; then, aging treatment: holding at 500℃±10℃ for 2 hours, followed by air cooling. Finally, tensile testing was performed at room temperature according to GB / T228.1-2021, and the results are shown in Table 5.

[0049] Table 5: Room temperature tensile test results of Comparative Example 1 Therefore, it can be seen that although the traditional solution treatment and aging heat treatment process used in Comparative Example 1 can make the tensile strength of the Z-direction specimen reach 1052~1041MPa and the elongation 12.0%~12.5%, the elongation of the XY-direction specimen is only 9.5%~10.5%, and the reduction of area is as low as 54.5%, which is significantly lower than the ≥11% elongation and ≥60% reduction of area required by the GJB7960-2012 standard.

[0050] This indicates that, due to the significant differences in microstructure and internal stress distribution between SLM-manufactured specimens and forged or cast components, the traditional solution treatment followed by aging heat treatment alone leads to significant anisotropy along the XY and Z directions, particularly a marked decrease in transverse (XY) plasticity, even falling below standard requirements, making it difficult to meet the application requirements of high-toughness components. In contrast, the staged heat treatment process proposed in this application can significantly improve elongation in all directions while maintaining strength, reduce anisotropy, and achieve superior overall mechanical properties.

[0051] In summary, this application demonstrates the ability to efficiently fabricate S-03 alloy parts with large layer thicknesses (0.05~0.07mm) using infrared laser equipment, offering high manufacturing freedom and making it particularly suitable for complex structures and prototype manufacturing. Based on high-efficiency parameters, the maximum manufacturing efficiency of a single laser can reach 22.68 cm³ / h. Combined with the HBD-P400 four-laser equipment, the theoretical maximum manufacturing efficiency can reach 90.72 cm³ / h, significantly improving production capacity.

[0052] Furthermore, the staged heat treatment process provided in this application, compared to the traditional solution treatment followed by aging, can achieve higher elongation and toughness without significantly reducing strength, effectively improving the anisotropy problem of SLM-formed components. In contrast, if SLM-printed samples are treated according to traditional standard heat treatment methods, the elongation often results in low elongation, even below the standard requirements, making it difficult to meet the application requirements of high-performance components. The method in this application not only optimizes printing efficiency and density but also takes into account the balance and stability of mechanical properties.

[0053] In addition, those skilled in the art may make other changes within the spirit of this application. Of course, all such changes made in accordance with the spirit of this application should be included within the scope of protection claimed in this application.

Claims

1. A laser printing method for stainless steel powder, characterized in that, Including the following steps: A layer of stainless steel powder with a thickness of 0.05-0.07 mm is laid on the substrate or the previous solidified layer in the molding cavity. The stainless steel powder layer comprises, by mass fraction: carbon ≤0.03%, silicon ≤0.15%, manganese ≤0.15%, phosphorus ≤0.008%, sulfur ≤0.006%, chromium 11.5%~12.5%, nickel 9.0%~10.3%, molybdenum 0.5%~0.8%, titanium 0.15%~0.25%, aluminum ≤0.2%, and the balance iron. Under an inert gas protective atmosphere, according to the preset three-dimensional model slice data, the infrared laser beam is controlled to selectively scan the stainless steel powder layer according to a predetermined scanning strategy, so that the stainless steel powder layer being scanned and irradiated melts and solidifies to form a cladding layer. Repeat the above steps, printing layer by layer until the 3D component is complete, wherein the scanning strategy includes any of the following parameter packages: (1) Infrared laser power 200-250W, scanning spacing 0.08-0.11mm, scanning speed 700-900mm / s; (2) Infrared laser power 250-300W, scanning spacing 0.08-0.11mm, scanning speed 900-1100mm / s; (3) Infrared laser power 300-400W, scanning spacing 0.07-0.09mm, scanning speed 800-1000mm / s.

2. The laser printing method as described in claim 1, characterized in that, The predetermined scanning strategy further includes performing an S-shaped reciprocating filling scan in the internal region of the two-dimensional cross-section corresponding to the three-dimensional model slice data.

3. The laser printing method as described in claim 2, characterized in that, The predetermined scanning strategy further includes: rotating the filling scanning direction of each layer by 67° relative to the previous layer, and performing a contour scan of the two-dimensional cross-section after completing the filling scan of the internal region.

4. The laser printing method as described in claim 1, characterized in that, The parameters are as follows: the scanning interval is 0.09 mm, the laser power is 250 W, the scanning speed is 900 mm / s, and the corresponding volume energy density Ev is 51.44 J / mm². 3 .

5. The laser printing method as described in claim 1, characterized in that, The parameters are as follows: the scanning interval is 0.09 mm, the laser power is 350 W, the scanning speed is 900 mm / s, and the corresponding volume energy density Ev is 72.02 J / mm². 3 .

6. The laser printing method as described in claim 1, characterized in that, The parameters are as follows: the scanning interval is 0.1 mm, the laser power is 300 W, the scanning speed is 1050 mm / s, and the corresponding volume energy density Ev is 47.62 J / mm². 3 .

7. The laser printing method as described in claim 1, characterized in that, The thickness of the stainless steel powder layer is 0.06 mm.

8. The laser printing method as described in claim 1, characterized in that, The inert gas is argon or nitrogen, and the wavelength of the infrared laser beam is 1064 nm.

9. A stainless steel three-dimensional component prepared by the laser printing method according to any one of claims 1 to 8, characterized in that, The density of the three-dimensional component is not less than 99.991%.

10. A heat treatment method for a three-dimensional component as described in claim 9, characterized in that, Including the following steps: The three-dimensional component is heated to 600℃-900℃ and held for 1-5 hours, then air-quenched. The three-dimensional component is heated to 600℃-900℃ and held for 1-5 hours, then air-quenched. The three-dimensional component is heated to 400℃-700℃ and held for 2-5 hours, then cooled by air.

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