CN114871451B - High-formability aluminum alloy material based on laser beam shaping and preparation method thereof - Google Patents

Abstract

The invention discloses a high-formability aluminum alloy material based on laser beam shaping and a preparation method thereof, wherein laser powder bed fusion forming equipment is modified to enable laser Gaussian beams emitted by the laser powder bed fusion forming equipment to be shaped into non-Gaussian beams; using computer aided design software to establish a three-dimensional entity geometric model of a target part, slicing the model in layers by using the software, planning a laser scanning path, and dispersing the three-dimensional entity into a series of two-dimensional data; and (3) introducing the obtained data into laser powder bed fusion forming equipment, and fusing and solidifying the aluminum alloy powder layer by layer to form the uniform and compact three-dimensional solid part. The invention adopts the shaped beam in the laser additive manufacturing process, and the shaped Bessel beam, the annular beam and the like have new spatial energy distribution, thereby meeting the requirements of specific materials or applications. The shaped beam stabilizes the laser melt pool turbulence and inhibits the initiation of thermal cracks in the laser forming by reducing the thermal gradient and increasing the melt pool solidification time, ultimately resulting in a high forming quality component.

Description

High-formability aluminum alloy material based on laser beam shaping and preparation method thereof

Technical Field

The invention belongs to the innovative field of laser additive manufacturing processes, and relates to a high-formability aluminum alloy material based on laser beam shaping and a preparation method thereof.

Background

The laser additive manufacturing is to melt metal powder by high-energy laser, so that the metal powder is melted, solidified and accumulated rapidly, and the three-dimensional part is formed rapidly in a layer-by-layer superposition mode. The laser additive manufacturing is widely applied to the fields of aviation, aerospace, national defense, medical treatment and health and the like by virtue of the advantages of high forming speed, high forming precision, short manufacturing period, designable structure height, high material utilization rate and the like.

With the rapid development of the aerospace industry, the demand for lightweight high-performance metal materials is also increasing. Aluminum alloy has excellent properties such as high specific strength, high specific modulus, fatigue resistance, corrosion resistance and the like, so that the aluminum alloy becomes a key material for realizing the structure weight reduction in the aerospace field. In order to meet the severe conditions of aerospace use, a relatively large number of 2000-series and 7000-series aluminum alloys are used. The main components of the 2000 series aluminum alloy are mainly 3 elements of aluminum (Al), copper (Cu) and magnesium (Mg), and the main components of the 7000 series aluminum alloy are aluminum (Al) and zinc (Zn). Aluminum alloys such as aluminum zinc alloy, aluminum magnesium alloy, aluminum lithium alloy and the like have a wider solidification temperature range, laser energy excessively gathered by Gaussian beams can cause high solidification rate and large temperature gradient of a molten pool, and the large temperature gradient in the molten pool is easy to generate thermal stress concentration and form thermal cracks in a formed part, and the thermal cracks serve as crack sources in the bearing process, so that early fracture failure of materials occurs.

Disclosure of Invention

The invention aims to solve the problems of poor formability and easiness in crack generation of crack sensitive aluminum alloy in laser additive manufacturing.

In order to solve the technical problems, the invention adopts the following technical scheme:

a preparation method of a high-formability aluminum alloy material based on laser beam shaping comprises the following steps:

(1) Modifying laser powder bed fusion forming equipment to enable laser Gaussian beams emitted by the laser powder bed fusion forming equipment to be shaped into non-Gaussian beams;

(2) Establishing a three-dimensional entity geometric model of a target part by using computer aided design software, and then slicing the model in layers and planning a laser scanning path by using Materialise Magics software to disperse the three-dimensional entity into a series of two-dimensional data;

(3) And (3) introducing the data obtained in the step (2) into laser powder bed fusion forming equipment, and fusing and solidifying the aluminum alloy powder layer by layer to form the uniform and compact three-dimensional solid part.

Specifically, in the step (1), the method for shaping the laser gaussian beam into the non-gaussian beam comprises the following steps: the Gaussian beam output by the laser passes through a pair of conical mirrors with the axial distance of 3-8 cm and the wedge angle of 0.05-0.15 rad, the incident beam is refracted, the plane wave and the surface wave vector of the conical element are interfered, and finally, the Bessel beam is formed on the substrate through the focusing element. If the focusing element is removed, the incident beam is directly irradiated on the substrate after being refracted by the conical mirror, and then an annular beam is formed.

Optionally, in the step (3), the aluminum alloy powder is aluminum lithium alloy; wherein, the copper content is 4.0 to 5.2wt percent, the lithium content is 0.90 to 1.50wt percent, the magnesium content is 0.25 to 0.80wt percent, the zirconium content is 0.08 to 0.16wt percent, and the balance is aluminum; the grain size of the aluminum-lithium alloy powder is 25-55 mu m.

Optionally, in step (3), the aluminum alloy powder is an aluminum magnesium alloy; wherein the magnesium content is 4.25-5.30 wt%, the manganese content is 0.25-0.65 wt%, the iron content is 0.05-0.25 wt%, and the balance is aluminum; the grain size of the aluminum magnesium alloy powder is 16-48 mu m.

Optionally, in the step (3), the aluminum alloy powder is aluminum zinc alloy; wherein, the zinc content is 4.8 to 5.6wt percent, the magnesium content is 1.90 to 2.80wt percent, the copper content is 1.00 to 1.80wt percent, the silicon content is 0.22 to 0.43wt percent, the iron content is 0.30 to 0.70wt percent, and the balance is aluminum; the grain size of the aluminum zinc alloy powder is 15-40 mu m.

Specifically, in the step (3), the laser power used for laser molding is 300-450W, and the laser scanning speed is 900-1300 mm/s. Preferably, SLM-150 laser powder bed fusion apparatus is used which essentially comprises a 500W IPG laser, a laser forming chamber, an automatic powder spreading system, a protective atmosphere device, computer control circuitry and a cooling circulation system. Before forming, fixing the aluminum alloy substrate subjected to sand blasting treatment on a workbench of laser powder bed fusion forming equipment, leveling, sealing a forming cavity through a sealing device, vacuumizing, and introducing inert gas. The laser powder bed fusion forming process is as follows: (a) The powder spreading device uniformly spreads the powder to be processed on the forming substrate, and the laser beam scans the slicing area row by row according to a pre-designed scanning path to enable the powder layer to be melted/solidified rapidly, so that a first two-dimensional plane of the part to be formed is obtained; (b) The computer control system enables the forming substrate to descend by one powder layer thickness, the powder supply cylinder piston ascends by one powder layer thickness, the powder spreading device re-spreads one layer of powder to be processed, and the high-energy laser beam finishes scanning of a second layer of powder according to slicing information so as to obtain a second two-dimensional plane of the part to be formed; (c) Repeating the step (b), and forming the powder to be processed layer by layer until the part to be formed is processed. The scanning interval is 50 μm, the powder spreading thickness is 40 μm, and a zoned island scanning strategy is adopted. The laser parameters are determined after process optimization.

Furthermore, the high-formability aluminum alloy material prepared by the preparation method is also within the protection scope of the invention.

The invention further provides laser powder bed fusion forming equipment, which comprises a laser system, a beam expander and a reflecting mirror, wherein a pair of conical mirrors are arranged at the rear end of the reflecting mirror, the axial distance of the two conical mirrors is 3-8 cm, the wedge angle is 0.05-0.15 rad, and the arrangement directions are opposite; the laser beam emitted by the laser system forms Gaussian beam through the beam expander and changes the direction of the light path through the reflecting mirror, then the incident beam is refracted through the pair of conical mirrors, the plane wave interferes with the surface wave vector of the conical mirror element, and finally a non-Gaussian beam is formed on the substrate.

Preferably, the non-Gaussian beam is a Bessel beam or an annular beam; when the light beam is an annular light beam, the light beam directly irradiates on the substrate to form the annular light beam after passing through the conical mirror element; in the case of Bessel beams, a focusing element is arranged at the rear end of the conical mirror element, so that the incident beam is refracted by the conical mirror, focused by the focusing element and irradiated on the substrate to form the Bessel beams.

The beneficial effects are that:

1. the invention adopts the shaped light beam in the laser additive manufacturing process, and the shaped light beam (Bessel light beam, annular light beam and the like) has new space energy distribution, thereby meeting the requirements of specific materials or applications. The beam stabilizes the laser bath turbulence and inhibits thermal crack initiation in laser forming by reducing thermal gradients and increasing bath solidification time, ultimately resulting in a high forming quality component.

2. The invention only carries out simple modification on the existing laser additive manufacturing equipment, does not damage the original functions and structures, and has simple operation. The Gaussian beam is shaped into the non-Gaussian beam (Bessel beam, annular beam and the like) by integrating the simple optical element, so that the shaping efficiency of the aluminum alloy is improved, excessive evaporation loss and performance reduction of low-melting-point alloy elements are avoided, and the crack-sensitive aluminum alloy manufactured by laser additive is truly applicable to actual production.

3. Compared with the traditional processing modes such as casting, forging, welding, machining and material reduction, the method provided by the invention has the advantages that the laser additive manufacturing technology is used for manufacturing the high-strength aluminum alloy component creatively, the degree of freedom of part design is greatly improved, the number of parts is reduced, and the production and manufacturing of the high-strength aluminum alloy component with complex structures such as topological optimization, bionic design and the like are possible. The formed component is suitable for the fields of aerospace, medical health and the like with small batch, high forming quality, light weight, customization and complicating requirements, and widens the application field of high-strength aluminum alloy.

Drawings

The foregoing and/or other advantages of the invention will become more apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawings and detailed description.

FIG. 1 is a schematic diagram of an apparatus for performing beam shaping in laser additive manufacturing according to the present invention, wherein the 1-laser system, 2-beam expander, 3-mirror, 4-cone mirror, 5-focusing element, 6-substrate, and other unchanged components of the laser powder bed melt forming apparatus are not shown.

Fig. 2 is a simulation result of powder melting during beam forming of aluminum lithium alloy samples by bessel according to example 1.

FIG. 3 is a simulation result of the temperature distribution of the molten pool and the dynamics of the molten pool in the process of forming an aluminum-lithium alloy sample by using the Bessel beam in example 1.

FIG. 4 is a simulation result of the temperature gradient and solidification time of a molten pool during the formation of an aluminum-lithium alloy sample by using a Bessel beam in example 1.

Fig. 5 is an optical image of a bessel beam-formed aluminum lithium alloy sample of example 1.

FIG. 6 is an optical image of a ring beam formed aluminum magnesium alloy sample of example 2.

Fig. 7 is an optical image of a bessel beam-formed aluminum zinc alloy sample of example 3.

FIG. 8 is a simulation result of powder melting, bath temperature distribution and bath solidification time of a sample of comparative example 1 Gaussian beam-formed aluminum-lithium alloy.

Fig. 9 is an optical image of a comparative example 1 gaussian beam-formed aluminum lithium alloy specimen.

Fig. 10 is an optical image of a bessel beam-formed aluminum lithium alloy sample of comparative example 2.

Detailed Description

The invention will be better understood from the following examples.

Fig. 1 shows a laser powder bed fusion forming device modified in the present invention, firstly, a laser beam emitted by a laser system 1 forms a gaussian beam through a beam expander 2 and changes the direction of the optical path of the gaussian beam through a reflecting mirror 3; then, the Gaussian beam outputted from the laser is passed through a pair of conical mirrors 4 having an axial distance of 3 to 8cm and a wedge angle of 0.05 to 0.15rad, the incident beam is refracted, the plane wave interferes with the surface wave vector of the conical element, and finally, a Bessel beam is formed on a substrate 6 by a focusing element 5. When the focusing element 5 is removed and the incident beam is refracted by the cone mirror 4 and then directly irradiated onto the substrate 6, an annular beam is formed.

Example 1

(1) The aluminum-lithium alloy comprises 4.0-5.2 wt.% of copper, 0.90-1.50 wt.% of lithium, 0.25-0.80 wt.% of magnesium, 0.08-0.16 wt.% of zirconium and the balance of aluminum, wherein the grain size of the aluminum-lithium alloy powder is 25-55 mu m.

(2) By means of the mode shown in fig. 1, a forming device is initially improved by integrating a simple optical element, gaussian beams output by a laser are passed through a pair of conical mirrors with axis distances of 3-8 cm and wedge angles of 0.05-0.15 rad, incident beams are refracted, plane waves and surface wave vectors of the conical elements are interfered, and Bessel beams are finally formed through a focusing element.

(3) And establishing a three-dimensional solid geometric model of the target part by using computer aided design software, and then slicing the model in layers by using Materialise Magics software, and setting a laser scanning path and laser process parameters. Wherein the laser process parameters are set as follows: the laser power is 300W, the laser scanning speed is 900mm/s, the scanning interval is 50 mu m, the powder spreading layer thickness is 40 mu m, a zonal scanning strategy is adopted, the zonal size is 5mm, and the adjacent layers are rotated by 37 degrees.

(4) And after the forming is finished, separating the part from the substrate by utilizing linear cutting, and obtaining the aluminum-lithium alloy block sample.

Based on a finite volume method, a mesoscale model of heat and mass transfer, melting and solidification of a melt in a laser molten pool is established, a computational fluid dynamics software FLUENT simulation is utilized to analyze the powder melting process and the change rule of the temperature distribution, the thermal gradient and the cooling rate of the molten pool in the process of forming an aluminum zinc alloy sample by using Bessel beams, and simulation results are shown in figures 2-4. From the simulation results shown in fig. 2-4, it can be seen that under the action of the bessel beam, the aluminum-lithium alloy powder is fully melted to form a molten pool with a smaller depth-to-width ratio, the temperature distribution of the molten pool is relatively uniform, the thermal gradient is smaller, the turbulence in the molten pool is stable, and after the forming time reaches 250 mu s, the temperature of each part of the molten pool has a tendency to rise, so that the solidification time of the liquid phase is prolonged, the liquid phase has enough time to fill the solidification shrinkage gap, and the formation of thermal cracks is inhibited.

Grinding and polishing the Bessel beam formed aluminum zinc alloy block sample according to a standard metallographic sample preparation method, wherein a light mirror picture is shown in fig. 5, no obvious cracks exist in the formed aluminum lithium sample, only a small amount of micro pores exist, the laser formability is high, and the forming density reaches 99.4%.

Example 2

(1) The aluminum magnesium alloy contains 4.25-5.30 wt.% of magnesium, 0.25-0.65 wt.% of manganese, 0.05-0.25 wt.% of iron and the balance of aluminum, and the grain size of the aluminum magnesium alloy powder is 16-48 mu m.

(2) By means of the mode shown in fig. 1, the forming equipment is initially improved by integrating a simple optical element, a focusing element 5 is removed, gaussian beams output by a laser pass through a pair of conical mirrors with axis distances of 3-8 cm and wedge angles of 0.05-0.15 rad, incident beams are refracted, and plane waves and surface wave vectors of the conical elements are interfered to form annular beams.

(3) And establishing a three-dimensional solid geometric model of the target part by using computer aided design software, and then slicing the model in layers by using Materialise Magics software, and setting a laser scanning path and laser process parameters. Wherein the laser process parameters are set as follows: the laser power is 375W, the laser scanning speed is 1100mm/s, the scanning interval is 50 mu m, the powder spreading layer thickness is 40 mu m, a zonal scanning strategy is adopted, the zonal size is 5mm, and the adjacent layers are rotated by 37 degrees.

(4) And after the forming is finished, separating the part from the substrate by utilizing linear cutting, and obtaining the aluminum-magnesium alloy block sample.

The annular beam formed aluminum-magnesium alloy block sample is polished and polished according to the standard metallographic sample preparation method, the photo-mirror picture is shown in figure 6, no thermal cracking is observed in the formed aluminum-magnesium sample, only a small amount of fine pores are formed, the laser formability is high, and the forming density is up to 99.1%.

Example 3

(1) The zinc content of the aluminum zinc alloy is 4.8 to 5.6wt percent, the magnesium content is 1.90 to 2.80wt percent, the copper content is 1.00 to 1.80wt percent, the silicon content is 0.22 to 0.43wt percent, the iron content is 0.30 to 0.70wt percent, the balance is aluminum, and the grain size of the aluminum zinc alloy powder is 15 to 40 mu m.

(2) The shaping equipment is primarily improved by integrating a simple optical element, gaussian beams output by a laser pass through a pair of conical mirrors with the axial distance of 3-8 cm and the wedge angle of 0.05-0.15 rad, the incident beams are refracted, surface wave vectors of plane waves and conical elements are interfered, and finally Bessel beams are formed by a focusing element.

(3) And establishing a three-dimensional solid geometric model of the target part by using computer aided design software, and then slicing the model in layers by using Materialise Magics software, and setting a laser scanning path and laser process parameters. Wherein the laser process parameters are set as follows: the laser power is 450W, the laser scanning speed is 1300mm/s, the scanning interval is 50 mu m, the powder spreading layer thickness is 40 mu m, a zonal scanning strategy is adopted, the zonal size is 5mm, and the adjacent layers are rotated by 37 degrees.

(4) And after the forming is finished, separating the part from the substrate by utilizing linear cutting, and obtaining the aluminum zinc alloy block sample.

The Bessel beam formed aluminum zinc alloy block sample is polished and polished according to the standard metallographic sample preparation method, the optical lens picture is shown in figure 7, no obvious crack exists in the formed aluminum zinc sample, only a small number of continuous micropores exist, the laser formability is high, and the forming density is as high as 99.7%.

Comparative example 1

Comparative example 1 the basic procedure was the same as in example 1, except that the gaussian beam was not shaped to directly laser additive shape the aluminum lithium alloy powder. Based on a finite volume method, a mesoscale model of heat and mass transfer, melting and solidification of a melt in a laser molten pool is established, a powder melting process, a change rule of a molten pool temperature distribution, a thermal gradient and a cooling rate in a Gaussian beam forming aluminum-lithium alloy sample process are simulated and analyzed by utilizing a computational fluid dynamics software FLUENT, and a simulation result is shown in figure 8. And (3) grinding and polishing the Gaussian beam forming aluminum-lithium alloy forming block sample according to a standard metallographic sample preparation method, wherein a photo-mirror picture is shown in fig. 9.

Compared with the shaping laser beam, the simulation results of the comparative example 1 and the photomicrograph of the prepared sample show that when the laser additive manufacturing shaping is directly carried out on the aluminum lithium alloy powder by using the non-shaped Gaussian beam, the laser energy is relatively concentrated, a molten pool with a larger depth-to-width ratio is formed, the temperature distribution of the molten pool is uneven, the thermal gradient is increased, the turbulence of the molten pool is strong and becomes unstable, the solidification time is shortened, a large amount of thermal cracks are generated in the shaped sample, the compactness of the shaped sample is reduced to 93.7%, and the shaping quality is obviously reduced. The aluminum-lithium alloy has a wider solidification temperature range, and a large temperature gradient is formed in a molten pool in the laser rapid melting solidification process, so that thermal stress concentration is easily generated in a formed part, and a large number of thermal cracks are generated. Meanwhile, coarse columnar dendrites are easy to form in the solidification process of the aluminum lithium alloy, liquid phases can still flow for feeding in the initial solidification stage, but the formed coarse columnar dendrites are connected with each other along with the reduction of the solidification temperature, the liquid phases which are not solidified are divided into small melt pools which are not communicated with each other, long and narrow gaps are formed among dendrites, the melt is difficult to reflow and fill, and the gaps are further expanded and connected with each other due to heat shrinkage generated by continuous cooling, so that thermal cracks penetrating multiple layers are formed, the laser formability is poor, and engineering application requirements are difficult to meet.

Comparative example 2

Comparative example 2 the basic procedure was the same as in example 1, except that the two conical mirrors were 12cm apart in axis, and the Bessel beam-formed aluminum-lithium alloy formed block samples were ground and polished according to the standard metallographic sample preparation method, and the mirror image was as shown in FIG. 10.

In this comparative example, no significant cracks were observed in the formed specimens, but a large number of voids were present, the forming quality was still poor, and the density was only 94.3%. The reason is that the axial distance of the conical lens is too large, laser beam energy is too dispersed, so that laser energy input is insufficient, aluminum lithium alloy powder cannot be sufficiently melted and spread in the laser forming process, a large number of unmelted pores are formed, and laser formability is poor.

Comparative example 3

Comparative example 3 the basic procedure is the same as in example 1, except that a cone lens having a wedge angle of 0.4rad is used. In this comparative example, a large number of voids appeared in the molded sample, and the density was reduced to 95.6%. This is because the wedge angle is too large, the laser beam energy is too dispersed and difficult to focus, so that the laser energy input is insufficient to completely melt the aluminum-lithium alloy powder, and meanwhile, the laser energy density is low, the aluminum-lithium alloy melt cannot be sufficiently wetted and spread, and a large number of unmelted pores appear in the laser formed sample.

The invention provides a high-formability aluminum alloy material based on laser beam shaping and a method for preparing the same, and the method for realizing the technical scheme is a plurality of methods and paths, the above is only a preferred embodiment of the invention, and it should be pointed out that a plurality of improvements and modifications can be made by those skilled in the art without departing from the principle of the invention, and the improvements and modifications are also considered as the protection scope of the invention. The components not explicitly described in this embodiment can be implemented by using the prior art.

Claims (8)

1. The preparation method of the high-formability aluminum alloy material based on laser beam shaping is characterized by comprising the following steps of:

(1) Modifying laser powder bed fusion forming equipment to enable laser Gaussian beams emitted by the laser powder bed fusion forming equipment to be shaped into non-Gaussian beams;

(2) Establishing a three-dimensional entity geometric model of a target part by using computer aided design software, and then slicing the model in layers and planning a laser scanning path by using Materialise Magics software to disperse the three-dimensional entity into a series of two-dimensional data;

(3) Introducing the data obtained in the step (2) into laser powder bed fusion forming equipment, and fusing and solidifying the aluminum alloy powder layer by layer to form a uniform and compact three-dimensional solid part;

in the step (1), the non-Gaussian beam is a Bessel beam or an annular beam;

in the step (3), the aluminum alloy powder is aluminum lithium alloy, aluminum magnesium alloy or aluminum zinc alloy;

in the step (1), the method for shaping the laser Gaussian beam into the non-Gaussian beam comprises the following steps: and passing the Gaussian beam output by the laser through a pair of conical mirrors with the axial distance of 3-8 cm, the wedge angle of 0.05-0.15 rad and opposite arrangement directions, refracting the incident beam, and interfering the plane wave with the surface wave vector of the conical element to form a non-Gaussian beam.

2. The method for producing a high formability aluminum alloy material based on laser beam shaping as claimed in claim 1, wherein in the step (3), the aluminum alloy powder is an aluminum lithium alloy; wherein the copper content is 4.0-5.2 wt%, the lithium content is 0.90-1.50 wt%, the magnesium content is 0.25-0.80 wt%, the zirconium content is 0.08-0.16 wt%, and the balance is aluminum; the grain size of the aluminum-lithium alloy powder is 25-55 mu m.

3. The method for producing a high formability aluminum alloy material based on laser beam shaping as claimed in claim 1, wherein in the step (3), the aluminum alloy powder is an aluminum magnesium alloy; wherein the magnesium content is 4.25-5.30wt%, the manganese content is 0.25-0.65wt%, the iron content is 0.05-0.25wt%, and the balance is aluminum; the grain size of the aluminum magnesium alloy powder is 16-48 mu m.

4. The method for producing a high formability aluminum alloy material based on laser beam shaping as claimed in claim 1, wherein in the step (3), the aluminum alloy powder is an aluminum zinc alloy; wherein the zinc content is 4.8-5.6wt%, the magnesium content is 1.90-2.80wt%, the copper content is 1.00-1.80wt%, the silicon content is 0.22-0.43wt%, the iron content is 0.30-0.70wt%, and the balance is aluminum; the grain size of the aluminum zinc alloy powder is 15-40 mu m.

5. The method for producing a highly formable aluminum alloy material based on laser beam shaping as claimed in claim 1, wherein in the step (3), the laser power used for laser shaping is 300 to 450W and the laser scanning speed is 900 to 1300mm/s.

6. The high-formability aluminum alloy material prepared by the preparation method of any one of claims 1 to 5.

7. The laser powder bed fusion forming device is characterized by comprising a laser system (1), a beam expander (2) and a reflecting mirror (3), and is characterized in that a pair of conical mirrors (4) are arranged at the rear end of the reflecting mirror (3), the axial distance of the two conical mirrors (4) is 3-8 cm, the wedge angle is 0.05-0.15 rad, and the arrangement directions are opposite; the laser beam emitted by the laser system (1) forms a Gaussian beam through the beam expander (2) and changes the light path direction of the Gaussian beam through the reflecting mirror (3), then the incident beam is refracted through the pair of conical mirrors (4), the plane wave interferes with the surface wave vector of the conical mirror (4) element, and finally a non-Gaussian beam is formed on the substrate (6); the non-Gaussian beam is a Bessel beam or an annular beam; the forming equipment is used for forming aluminum alloy powder, wherein the aluminum alloy powder is aluminum lithium alloy, aluminum magnesium alloy or aluminum zinc alloy.

8. The laser powder bed fusion forming apparatus as claimed in claim 7, wherein when the non-gaussian beam is an annular beam, the beam is transmitted through the cone mirror (4) element and then directly irradiated onto the substrate (6) to form the annular beam; when the non-Gaussian beam is Bessel beam, a focusing element (5) is arranged at the rear end of the conical mirror (4) element, so that the incident beam is refracted by the conical mirror (4), focused by the focusing element (5) and irradiated on a substrate (6) to form the Bessel beam.

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