CN112191844A - 3D printing method of aluminum-copper alloy - Google Patents
3D printing method of aluminum-copper alloy Download PDFInfo
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- CN112191844A CN112191844A CN202010916970.1A CN202010916970A CN112191844A CN 112191844 A CN112191844 A CN 112191844A CN 202010916970 A CN202010916970 A CN 202010916970A CN 112191844 A CN112191844 A CN 112191844A
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- WPPDFTBPZNZZRP-UHFFFAOYSA-N aluminum copper Chemical compound [Al].[Cu] WPPDFTBPZNZZRP-UHFFFAOYSA-N 0.000 title claims abstract description 223
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- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 50
- 238000007639 printing Methods 0.000 claims abstract description 40
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- JRBRVDCKNXZZGH-UHFFFAOYSA-N alumane;copper Chemical compound [AlH3].[Cu] JRBRVDCKNXZZGH-UHFFFAOYSA-N 0.000 description 5
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/24—After-treatment of workpieces or articles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/06—Making metallic powder or suspensions thereof using physical processes starting from liquid material
- B22F9/08—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying
- B22F9/082—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y10/00—Processes of additive manufacturing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y70/00—Materials specially adapted for additive manufacturing
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/24—After-treatment of workpieces or articles
- B22F2003/248—Thermal after-treatment
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/06—Making metallic powder or suspensions thereof using physical processes starting from liquid material
- B22F9/08—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying
- B22F9/082—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid
- B22F2009/0824—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid with a specific atomising fluid
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
- B22F2998/10—Processes characterised by the sequence of their steps
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Abstract
A method for 3D printing of aluminum-copper alloy comprises the following steps: generating a 3D digital model of a sample to be printed, cutting the 3D digital model into an image sequence, and controlling the printing direction according to the slicing direction of the model; mixing aluminum powder and copper powder, and carrying out atomization treatment to form aluminum-copper atomized powder; introducing inert gas, preheating a substrate, printing according to set parameter control, paving aluminum copper powder by controlling a powder paving roller to move left and right according to the image and the powder paving parameters, and controlling the optical fiber laser to selectively melt the aluminum copper powder layer by layer according to the image and the set parameters to perform layer-by-layer accumulation and printing of a primary sample piece; carrying out heat treatment on the initial sample; according to the 3D printing method for the aluminum-copper alloy, the 3D printing rapid forming technology is short in period, high in processing complexity and high in efficiency, different process parameters can be adjusted when the aluminum-copper alloy part is processed, partial defects of the traditional process method for manufacturing the aluminum alloy part are overcome, and the overall performance of the printed prototype part can be improved remarkably through heat treatment.
Description
Technical Field
The invention relates to the technical field of rapid forming of aluminum-copper alloy, in particular to a method for 3D printing of aluminum-copper alloy.
Background
The traditional aluminum-copper alloy processing technology has two types, namely a deformation processing method and a casting forming method, wherein the aluminum-copper alloy parts processed by the casting forming method can well meet the performance requirements of actual parts, and have higher mechanical properties in the aspects of strength, hardness and the like, but the traditional processing technology has the following defects:
the first is oxidizing slag inclusion, which often occurs in the traditional aluminum copper alloy casting process and is mostly generated at the corner part with unsmooth ventilation of the aluminum copper casting mold cavity; the reasons for the oxidation slag inclusion phenomenon of the aluminum-copper alloy are manifold, firstly, the impurities of furnace materials for processing the aluminum-copper alloy are the main reasons for the oxidation slag inclusion, secondly, the oxidation slag inclusion phenomenon can also be caused by the poor design of a mould of an aluminum-copper alloy casting and pouring system, and finally, the slag inclusion phenomenon can also be caused by the improper method of a basic operator in the pouring control process.
Secondly, the aluminum copper alloy is easy to generate air holes and air bubbles in the casting process, which is an inevitable defect of the aluminum copper alloy in the casting process, if the aluminum copper alloy is improperly controlled in the process, the internal structure of the aluminum copper alloy is greatly affected, the overall performance of the aluminum copper alloy is seriously reduced, firstly, the air can be brought into a cavity by aluminum copper alloy parts in the casting process to cause the air holes and the air bubbles, and secondly, the aluminum copper alloy casting and pouring system is unreasonably designed to cause the air holes and the air bubbles.
And thirdly, shrinkage porosity which is also an inevitable processing defect in the traditional casting processing method of the aluminum-copper alloy, generally occurs at the riser end of an ingate, and causes the shrinkage porosity in many aspects, firstly, poor feeding effect at the riser of a cast aluminum-copper alloy part is a main cause of shrinkage porosity, secondly, in the processing process of the cast aluminum-copper alloy part, the shrinkage porosity can also be caused when the gas content in a casting cavity is increased, and finally, the shrinkage porosity can be caused when the runner in the cavity of the cast aluminum-copper alloy part is overheated, and the aluminum-copper alloy is caused by overlarge part of crystalline grains and improper position placement in the casting processing process.
And thirdly, cracks are formed, in the traditional casting process, part of the bonding stress is concentrated to form a stress area due to the fact that the aluminum alloy is cooled at an excessively high speed in casting, the phenomenon of cracking of the partial layer of the aluminum-copper alloy is seriously caused, the phenomenon of a large number of cracks of the aluminum-copper alloy powder in the process of processing is effectively avoided, the most important is to find a balance point of the mixed pure aluminum and pure copper, and the factors of the whole temperature, the bonding melting point and the like of the aluminum-copper alloy powder are fully considered. First, when casting aluminum-copper alloy parts, if the casting temperature is not properly controlled, cracks, warpage, etc. of the aluminum-copper alloy may occur. Secondly, the internal system of the aluminum-copper alloy casting cavity is poorly designed, the wall thickness is greatly different, or sharp corners are formed at part of corners, and the like, and particularly, in the aluminum-copper alloy casting process, when the heat preservation time of the casting cavity is not properly controlled, the defects of cracks, warping and the like can be caused. Finally, in the early stage of casting the aluminum-copper alloy, the phenomenon that the aluminum-copper alloy cracks in the traditional process is avoided due to the fact that the temperature of the poured aluminum-copper liquid is too high is a precondition for ensuring that parts of the aluminum-copper alloy obtain obvious performance.
In view of the technical defects existing in the traditional casting process, the newly developed laser rapid prototyping 3D printing technology can well improve the defects of bubbles, shrinkage porosity, cracks and the like in the manufacturing process, so that the invention provides the method for 3D printing of the aluminum-copper alloy, and the processed aluminum-copper alloy parts can meet the use requirements in the aspects of tensile strength, density and the like.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a method for 3D printing of aluminum-copper alloy, which can effectively improve the defects of bubbles, shrinkage porosity, cracks and the like in the manufacturing process so as to further improve the manufacturing quality of aluminum-copper alloy parts.
A method of 3D printing an aluminum-copper alloy, the method comprising the steps of:
s1 digital-to-analog slicing: generating a 3D digital model of a sample to be printed according to a part model, slicing the 3D digital model to form an image sequence which can be identified by a 3D printer, wherein each image in the image sequence represents one layer of the 3D digital model, and controlling a 3D printing track according to a slicing path of the image sequence of the digital model;
s2 powder atomization treatment: mixing copper powder and aluminum powder in a certain proportion, and carrying out atomization treatment to form aluminum-copper atomized powder;
s3 aluminum bronze powder 3D printing: introducing inert protective gas into a printing chamber of the 3D printer, preheating a matrix, setting powder paving parameters and printing parameters of the 3D printer, controlling a powder paving roller to pave the aluminum copper atomized powder in the step S2 according to the image sequence and the powder paving parameters in the step S1, and controlling the fiber laser to melt the aluminum copper powder layer by layer according to the 3D printing track and the printing parameters in the step S1 to perform layer-by-layer accumulation printing to obtain an initial sample;
s4 primary sample heat treatment: and carrying out solid solution aging heat treatment on the initial sample to obtain a printing sample.
Further, in the step S2, the powder atomization treatment is performed by using a high-pressure Ar gas flow to crush the molten aluminum-copper metal liquid flow into liquid droplets and condensing the liquid droplets to obtain aluminum-copper atomized powder; the pressure of the high-pressure Ar airflow is 1.5-2.5 MPa;
preferably, the particle size of the aluminum-copper atomized powder after screening is 20-40 μm;
preferably, the copper powder and the aluminum powder are mixed in a mass ratio of 1:10 to 1: 5.
Further, in step S3, the inert shielding gas is Ar gas; the substrate is a 6061 aluminum alloy substrate, and the preheating substrate is preheated by laser at the preheating temperature of 60-70 ℃ for 4-7 seconds each time for 3-4 times;
preferably, the powder paving thickness of each powder paving parameter is 0.03-0.04 mm;
preferably, when the fiber laser is used for printing, the printing power of the printing parameters is 225-400W, the scanning speed is 800-1000 mm/s, and the scanning distance is 0.05-0.08 mm.
Further, step S3 includes, before 3D printing, the steps of: and (3) drying the aluminum copper powder in a vacuum drying oven at the drying temperature of 80-150 ℃ for 25-40 minutes.
Further, performing the solution aging treatment in the step S4, wherein the solution treatment temperature is 550-600 ℃, and the time of delayed heat preservation is 6-10 hours; the aging treatment temperature is 150-200 ℃, and the aging treatment time is 10-20 hours.
The 3D printing method for the aluminum-copper alloy can exert the advantages of short period, high processing complexity and high efficiency by adopting a 3D printing rapid forming technology. When the aluminum-copper alloy parts are processed, different process parameters can be adjusted, and partial defects of the aluminum alloy parts manufactured by the traditional process method are well overcome. The overall performance can be obviously improved by optimizing the technological parameters and the processing mode through the 3D printing and forming technology, and the method plays an obvious role in improving the comprehensive mechanical property of the aluminum-copper alloy product. In the laser rapid forming process, the die is not needed to directly print and form the aluminum-copper alloy parts on the substrate, so that the phenomena of cracks or shrinkage porosity and the like caused by uneven wall thickness or sharp corner protrusions and other factors in a casting cavity can be avoided. The laser rapid prototyping technology does not have the process of pouring liquid into a mould, but uses laser to directly bond the aluminum-copper alloy together. By utilizing the laser rapid prototyping technology, the design of a die or the design of an internal structure and other factors are not required to be considered, and the three-dimensional solid model can be processed only by guiding the designed three-dimensional solid model into the rapid prototyping machine and adjusting parameters. From the cost aspect: the parts processed by the laser rapid forming method have low cost and basically meet the practical requirements in the aspect of mechanics. From the aspects of environmental protection, resources and the like: the parts processed by the laser rapid forming method are pollution-free and environment-friendly. Is superior to the aluminum-copper alloy parts processed by the traditional method in the aspect of material utilization rate. From the aspect of period: the aluminum alloy parts processed by the rapid forming method have short period and are easy to process complex, porous and thin-walled parts. The advantages of the laser rapid forming can be fully exerted, the defects of bubbles, shrinkage porosity, cracks and the like in the manufacturing process are well avoided, and the processed aluminum-copper alloy parts basically meet the performance requirements in the aspects of tensile strength, density and the like. The rapid prototyping technology does not need to consider the influence of the pouring temperature on the parts. In addition, the printed initial sample is subjected to heat treatment, so that the performance of the aluminum-copper alloy part is further improved. Because the density of copper is much greater than that of aluminum, in the course of processing, the heavy copper powder quality leads to most copper powder to sink to the jar low in the course of processing, the unable accurate measurement of the comprehensive mechanical properties of the sample piece that processes out finally, some can lead to the internal structure segregation seriously, carry out atomization treatment to two kinds of powders of aluminium copper and melt into a powder, prepare good aluminium copper alloy powder, the aluminium copper alloy spare part mechanical properties that processes out satisfies the requirement basically, and segregation phenomenon improves to some extent, thereby improve the quality of aluminium copper alloy printing.
Drawings
FIG. 1 is a flow chart of 3D printing according to an embodiment of the present invention;
FIG. 2 is a schematic diagram illustrating a single scanning direction using grouped direction change in single scanning according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of a block turning single-pass scanning direction according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of the inner and outer helical single-pass scanning directions according to an embodiment of the present invention;
FIG. 5 is a microstructure of an aluminum bronze alloy preform according to an embodiment of the present invention;
FIG. 6 is a microstructure of an aluminum-copper alloy after solution treatment according to an embodiment of the present invention.
Detailed Description
The method for 3D printing of the aluminum-copper alloy comprises the following steps:
s1 digital-to-analog slicing: generating a 3D digital model of a sample to be printed according to the part model, slicing the 3D digital model to form an image sequence which can be identified by a 3D printer, wherein each image in the image sequence represents one layer of the 3D digital model, and controlling a 3D printing track according to a slicing path of the image sequence of the digital model; generating a 3D digital model of a sample to be printed, cutting the 3D digital model into an image sequence, wherein each image in the image sequence represents one layer of the 3D digital model, and controlling the printing direction according to the slicing direction of the model;
s2 powder atomization treatment: mixing copper powder and aluminum powder in a certain proportion, and carrying out atomization treatment to form aluminum-copper atomized powder; specifically, the powder atomization treatment is to crush molten aluminum-copper metal liquid flow into liquid drops by utilizing high-pressure Ar airflow, and obtain aluminum-copper atomized powder after condensation; the pressure of the high-pressure Ar gas flow is 1.5-2.5 MPa; the particle size of the aluminum-copper atomized powder is 20-40 mu m after screening; the copper powder and the aluminum powder are mixed in a mass ratio of 1: 10-1: 5.
S3 aluminum bronze powder 3D printing: firstly, putting the aluminum copper powder into a vacuum drying oven for drying, wherein the drying temperature is 80-150 ℃, and the drying time is 25-40 minutes; introducing inert protective gas into a printing chamber of the 3D printer, preheating a matrix, setting powder paving parameters and printing parameters of the 3D printer, controlling a powder paving roller to pave powder for the aluminum copper atomized powder in the step S2 according to the image sequence and the powder paving parameters in the step S1, and controlling the optical fiber laser to melt the aluminum copper powder layer by layer according to the printing track and the printing parameters in the step S13D to perform layer-by-layer accumulation printing to obtain an initial sample; the inert protective gas is Ar gas; the substrate is a 6061 aluminum alloy substrate, the preheating substrate is preheated by laser, the preheating temperature is 60-70 ℃, the preheating is carried out for 4-7 seconds each time, and the preheating is carried out for 3-4 times; the powder spreading thickness of each time of the powder spreading parameters is 0.03-0.04 mm; when the fiber laser is adopted for printing, the printing power of printing parameters is 225-400W, the scanning speed is 800-1000 mm/s, and the scanning interval is 0.05-0.08 mm;
s4 primary sample heat treatment: carrying out solid solution aging heat treatment on the initial sample to obtain a printing sample; carrying out solution aging treatment at the temperature of 550-600 ℃ for 6-10 hours; the aging treatment temperature is 150-200 ℃, and the aging treatment time is 10-20 hours.
And controlling the powder spreading thickness according to the powder spreading thickness parameter, and performing powder spreading printing according to picture control. And controlling the power, the scanning speed, the scanning interval and the like of the laser according to the set parameters. And printing according to the picture control.
Before 3D printing and forming, firstly, a digital model of a part to be printed needs to be drawn by using three-dimensional entity design software (such as CATIA). Then, the three-dimensional entity is partitioned and sliced to guide a forming machine to print layer by layer. The format of the part designed by the three-dimensional entity software is completely different from that of the 3D printer, and when the part is exported from the three-dimensional entity software, the part is converted into a format recognized by the 3D printer, such as STL format.
When the parts are converted to STL format, they can be imported into the printer. As shown in fig. 1, the printer then creates a realistic solid body by reading the cross-sections of the individual cut pieces in the digital model of the part, and then printing the adhesive layers layer by layer with the laser from the powdered material.
After the three-dimensional entity is designed, the format is converted, then slicing is carried out, and finally, the designed parts are guided into a printer to start printing.
Compared with the traditional processing technology, the rapid forming technology has the remarkable advantages that: firstly, the method is suitable for small-batch production and processing of complex parts, and secondly, the method is environment-friendly, cost-saving and short in period. Finally, the mold can be easily and quickly manufactured without personal supervision.
The powdery aluminum and the powdery copper of the present example preferably have a particle size of 20 to 40 μm.
The aluminum-copper alloy powder takes the comprehensive performance and other factors of the aluminum-copper alloy into consideration, and aluminum-copper alloy parts obtained after direct processing and manufacturing can not meet the actual requirements, because the density of copper is much higher than that of aluminum, in the processing process, the mass of copper powder is heavy, so that most of copper powder sinks to a cylinder in the processing process to be low, the comprehensive mechanical property of a finally processed sample block can not be accurately measured, and part of the sample block can cause serious internal tissue segregation, therefore, the two kinds of powder of aluminum and copper are atomized and melted into one kind of powder, so as to avoid the defects.
The aluminum-copper alloy is two chemical elements with large mass and large melting point difference, and parts with light mass and high mechanical property can be manufactured by combining the two chemical elements. However, when the two elements are combined due to the great influence of the temperature during the heat treatment, the segregation phenomenon of the structure is remarkable. Good aluminum-copper alloy powder can be well prepared by utilizing an aluminum-copper powder alloy atomization technology, the mechanical properties of the processed aluminum-copper alloy parts basically meet the requirements, and the segregation phenomenon is improved.
Another newly formed phase of the aluminum-copper alloy is CuAl2The formation of the phase makes up the properties of pure aluminum such as hardness, strength and the like. Therefore, the comprehensive mechanical property of the pure aluminum can be well improved by adding the proper copper element into the pure aluminum. Through microscopic structure analysis, the aluminum-copper alloy can generate chemical reaction to form a plurality of metallographic phases in the forming process, and segregation can be generated seriously.
The atomization heat treatment for the preparation of the aluminum powder copper powder of the embodiment: metal or metal alloy is smelted under the condition of gas protection, the metal alloy flows out (downwards) through a flow guide nozzle after passing through a heat-insulating crucible (a container for melting and refining metal liquid, heating solid and liquid and reacting, which is the basis for ensuring smooth chemical reaction), the metal liquid is atomized and crushed into a large number of fine liquid drops by high-pressure airflow through a nozzle, and the fine liquid drops are solidified into spherical or subsphaeroidal particles in flight.
In the actual operation process, the aluminum-copper alloy powder is repeatedly used and exposed in the air, so that the pure aluminum powder and the air are promoted to generate chemical reaction, and if the aluminum-copper alloy powder is not strictly processed in the laser rapid prototyping process, the powder is affected by moisture, so that the adhesion degree of the aluminum-copper alloy powder is affected, and the aluminum-copper alloy is seriously warped in the layer-by-layer superposition. And the aluminum-copper alloy is extremely easy to be damped in the air, and the comprehensive performance of laser forming parts is greatly influenced in serious cases, so that the powder needs to be dried in vacuum before the aluminum-copper powder is formed and processed, and the aim is to eliminate the factors such as the oxygen content of the moisture control powder in the powder and the like.
The drying of this embodiment is to dry aluminum powder and copper powder in a vacuum drying oven at 80-150 deg.C for 25-40 minutes. Preferably, drying is performed before the atomization treatment. After the vacuum drying oven is used for drying the aluminum-copper powder in vacuum, the processed parts are obviously improved in the aspects of comprehensive mechanical property and the like after being compared with aluminum-copper alloy parts which are not dried in vacuum, and the forming process is easy to stabilize.
The drying is carried out according to the actual situation of the aluminum copper powder, and if the drying degree of the powder is in a usable range or does not influence the later processing, the drying step is not carried out.
Considering that the oxidation of the aluminum-copper alloy is serious, inert gases such as high-purity argon and nitrogen can be continuously introduced in the processing process to ensure that the surface quality of the aluminum-copper alloy is not influenced by the oxidation of pure aluminum powder, and the phenomena of spheroidization, warping, cracking and the like can not occur in the processing process.
Considering that the oxidation phenomenon of the aluminum-copper alloy powder can occur in the processing process, the oxygen content is properly controlled in the experiment, and the air is aerated once every half hour when being proper, so that the purpose of preventing the oxidation of the aluminum-copper alloy from influencing the forming quality is realized.
In the process of processing and forming the aluminum-copper alloy, the proper range of processing of the aluminum-copper alloy parts is about 550-600 ℃. When the temperature is too high, the phenomenon of excessive melting of the aluminum-copper alloy can occur, and thus the surface quality of the aluminum-copper alloy can be directly influenced. When the temperature is too low, the aluminum-copper alloy powder layer cannot be melted to generate a black slag phenomenon.
In the 3D printing process, the influences of the performance, the temperature and the like of pure aluminum powder must be considered, and the substrate preheating can effectively reduce the temperature of the aluminum-copper alloy in the cooling stage and avoid cracks. The failure of the aluminum-copper alloy powder to bond to the aluminum alloy substrate occurs when the aluminum alloy substrate is not preheated.
In the laser rapid forming process, the subsequent detection can be influenced, and even the comprehensive mechanical property of the aluminum-copper alloy sample piece can be influenced, so that the substrate needs to be fully preheated when the aluminum-copper alloy sample piece is processed, and the powder feeding cylinder body is properly heated to ensure that the aluminum-copper alloy powder can be effectively bonded to the 6061 aluminum alloy substrate.
The preheating of the substrate 6061 is particularly important for alloy powder obtained by mixing aluminum and copper. When the preheating times of the substrate are too low or the preheating temperature is too low, the first layer of powder can not be bonded on the substrate. In the subsequent forming process, the early preheating is needed to ensure that the aluminum-copper alloy powder is effectively bonded to the substrate.
The 3D printing (metal powder) technology utilizes the integral accumulation principle to finish the processing of a sample piece, if the processing can cause that the first layer of powder and the substrate can not be bonded together on the premise that the substrate is not preheated, partial layer fracture, warping and other phenomena can be caused in the process of stacking layer by layer, in order to effectively avoid the phenomenon, the preheating temperature is increased in the early preheating process, and the preheating times are increased to effectively avoid the fracture and warping phenomena of the aluminum-copper alloy.
Further, the 6061 substrate is preheated by laser, the preheating temperature is 60-70 ℃, the preheating time is 4-7 seconds each time, and the preheating time is 3-4 times.
Further, the copper powder and the aluminum powder are mixed in a mass ratio of 1: 10-1: 5.
The chemical components and physical properties of the aluminum powder of the present example are as follows:
TABLE 1 chemical composition of aluminum powder
Table 2: physical properties of pure aluminum
The chemical composition and physical properties of the copper powder of this example are as follows:
TABLE 3 chemical composition of copper powders
TABLE 4 physical Properties of pure copper
In the rapid forming technology, the selection of proper process parameters is particularly important for forming good aluminum-copper alloy parts. When the laser power is too high, it is easy to cause excessive melting of the pure aluminum powder, which affects the overall performance, and even the segregation phenomenon mentioned above occurs. When the laser power is selected too small, pure aluminum or pure copper powder cannot be melted so that the two powders cannot be well bonded together, and the pure aluminum and the pure copper powder are promoted to be separated from each other under the microstructure.
When the scanning speed is fixed, the melting point of the aluminum-copper alloy is fixed along with the continuous increase of the laser power, and when the temperature is too high, the pure aluminum powder can be instantaneously overflowed, which is caused by the lower melting point of the pure aluminum powder, so that when the aluminum-copper alloy powder parts are processed, the selection of the proper laser power is particularly important for manufacturing the excellent aluminum-copper alloy parts.
Further, when the fiber laser of the embodiment is used for printing, the printing power is adjusted to 225-400W.
The aluminum-copper alloy parts processed by the Selective Laser Melting (SLM) forming technology cannot meet the practical use requirements, so that the aluminum-copper alloy parts can meet the requirements after proper heat treatment.
The laser of the present embodiment preferably uses CO2Laser light, wavelength is 10.6 um.
The comprehensive mechanical property of the aluminum-copper alloy powder prepared by the aluminum-copper alloy powder atomization technology can be well improved by carrying out solution treatment on parts printed and processed by 3D printing.
In this embodiment, a solution treatment process is used for the printed aluminum-copper alloy parts.
The composition and phase diagram of the aluminum-copper alloy after solution treatment are influenced by the heat preservation temperature. The higher the temperature, the closer to the eutectic transition temperature.
Further, after printing, the method also comprises the following steps: and carrying out solid solution treatment on the printed printing piece through time delay and heat preservation for 6-10 hours at the solid solution temperature of 550-600 ℃.
Specifically, in one embodiment of the present invention, the solution treatment is performed while setting the solution heat treatment temperature to 550 ℃. As is clear from the binary phase diagram analysis of the Al-Cu alloy, the solid solution was carried out by the time-lapse heat-retention method. When the prolonged time reaches 6-10 hours, the ideal state can be achieved, namely the mechanical comprehensive performance and the compactness are higher. When the grains of the aluminum-copper alloy are deeply analyzed, the following result is found after the heat preservation is continuously carried out for a longer time, and the growth of the aluminum grains is not obvious when the heat preservation time is longer. After the temperature reaches 550 ℃, the solution heat treatment method is adopted, and after long-time heat preservation, the comprehensive mechanical property of the aluminum-copper alloy part is obviously improved, and the density of the internal structure reaches an ideal state.
FIGS. 5 and 6 are a microstructure of an aluminum-copper alloy sample according to an embodiment of the present invention and a microstructure of an aluminum-copper alloy after solution treatment of the sample. After the parts processed by the aluminum-copper alloy laser melting forming technology are subjected to solution heat treatment, the overall mechanical property of the final aluminum-copper alloy parts is directly influenced by the length of the heat preservation time. When the holding time is gradually increased, the granularity of the internal structure of the aluminum-copper alloy is uniformly visible (as shown in figure 6).
The comprehensive mechanical property of the aluminum-copper alloy parts can be further improved by carrying out appropriate aging treatment after carrying out solution treatment on the aluminum-copper alloy parts.
The surface hardness before the aging treatment of the aluminum-copper alloy is relatively low. The directly processed aluminum-copper alloy parts cannot be directly applied to the fields of aerospace, automobiles, mechanical equipment and the like, and a proper heat treatment process is required to improve the comprehensive properties of wear resistance, corrosion resistance, tensile strength and the like of the aluminum-copper alloy parts.
Further, carrying out aging treatment on the printed product after the solution treatment, wherein the aging treatment temperature is 150-200 ℃, and the aging treatment time is 10-20 hours.
Specifically, when the aging temperature of the printed aluminum-copper alloy part is 150 ℃, the surface hardness and the comprehensive mechanical property of the aluminum-copper alloy are improved after the heat preservation time is properly prolonged.
The analysis shows that the change rule of the aluminum-copper alloy at 150 ℃ is obtained, namely the hardening effect of the aluminum-copper alloy is most obvious when the effective temperature reaches 150 ℃, and the comprehensive mechanical property of the aluminum-copper alloy is obviously improved when the effective time is controlled within a certain range.
When the aging temperature of the aluminum-copper alloy part is 170 ℃, the strength of the aluminum-copper alloy part exceeds 120MPa, after the heat preservation time is properly prolonged, the temperature is continuously increased to accelerate the diffusion of atoms, and the atoms are diffused and simultaneously precipitate along with strengthening metallographic phase, so that the hardness of the aluminum-copper alloy part is remarkably improved.
In the heat treatment process of the aluminum-copper alloy parts, the most effective method for ensuring the hardness of the aluminum-copper alloy is to properly control the aging temperature and the heat preservation time. However, the temperature cannot be increased at once, and when the temperature is increased to a certain temperature, the hardness is not increased, but the mechanical properties such as strength and hardness are gradually reduced, so that it is necessary to select an appropriate aging temperature and an appropriate time for improving the overall mechanical properties of the aluminum-copper alloy.
Selective Laser Melting (SLM) forming processes are limited by a number of factors. One of them is the scanning mode. Whether the scanning mode is selected correctly or not directly determines the quality of the aluminum-copper alloy forming part.
3D printing technology (metal) is affected by various factors, of which the main factor affecting the formation is the single pass scanning mode. Because the reaction of internal metal elements in the 3D printing process is extremely complex, the excellent single-channel scanning mode is particularly important for forming aerospace, machinery, automobiles and other parts with high compactness and strong mechanical property.
Through deep research on the forming defect rule of the aluminum-copper alloy in the selective laser melting forming process, the fact that the defects of each layer are accumulated layer by layer continuously in the processing process is found, the defects of the parts are finally warped, and the processed aluminum-copper alloy parts cannot be bonded to a pure aluminum substrate.
When the scanning speed is too fast, the energy heat emitted by the laser cannot be well absorbed by the aluminum-copper powder, which can indirectly cause energy dissipation, and finally, the aluminum-copper alloy can generate warping and stress concentration in the forming process. In the laser rapid prototyping experiment operation, because the scanning interval influences the density degree of the laser beam, when the laser scanning interval is set to be too large, the line width of the laser beam is increased, and under the condition, the laser energy is easy to dissipate, which indicates that the spheroidization phenomenon is easy to occur. In the rapid forming process, factors which need to be considered seriously for processing the aluminum-copper alloy sample piece by properly setting the scanning interval avoid the defects of warping, layering and the like in the processing process.
When the powder spreading thickness is large in the processing process, the energy emitted by laser cannot instantly melt the aluminum copper powder, and the partial aluminum copper powder does not have good laser absorption capacity, so that the partial aluminum copper powder is not well bonded with the upper layer of formed aluminum copper layer, and the warping phenomenon of the aluminum copper alloy in the processing process, the layering phenomenon caused by over-thick powder spreading in the processing process and the over-melting phenomenon caused by over-high power in the laser processing process can be caused.
The aluminum-copper alloy powder can be seriously spheroidized along with the continuous increase of the laser processing speed. When the scanning speed is increased to a certain degree, the temperature is constant, but the aluminum-copper alloy is directly warped due to the fact that the scanning speed is too high.
Further, in the present embodiment, it is preferable that the scanning speed used for printing is 800mm/s to 1000 mm/s. When the scanning speed is 800 mm/s-1000 mm/s, the variation of the single-channel scanning line width is stable. The change rule of the single line height is gradually reduced along with the gradual reduction of the speed. When the scanning speed of the laser is too fast, the absorption energy of the powder of the aluminum-copper alloy cannot be absorbed quickly, and the aluminum-copper alloy powder can be spheroidized and warped seriously. The rule which can be obtained through test data is that the scanning speed is most stable when 800 mm/s-1000 mm/s, and the comprehensive performance of the aluminum-copper alloy sample piece obtained through detection meets the practical requirement. When the scanning speed is gradually increased, particularly to 800 mm/s-1000 mm/s, the abrasion resistance and the like of the aluminum-copper alloy sample piece are obviously improved.
In the selective laser melting forming process, the powder spreading thickness has an extremely obvious influence on the forming of the aluminum-copper alloy, one of the reasons is that the technology is completed by using a layer-by-layer processing method, the powder spreading thickness directly influences the overall performance of the aluminum-copper alloy forming parts each time, and even the aluminum-copper alloy has cracks and warping due to different melting points.
Because the laser power of the selective laser melting forming processing is set to be certain, when the powder spreading thickness reaches a certain degree, the current laser power cannot penetrate through the powder layer, so that part of the powder cannot be melted and bonded together, and finally, the aluminum-copper alloy parts have the defects of warping, spheroidizing, cracking and the like.
In the 3D printing process, the influence of the constantly changing powder spreading thickness on the aluminum-copper alloy scanning surface layer is more obvious, the laser power cannot penetrate through the aluminum-copper alloy powder layer after the powder spreading thickness is gradually increased, and part of the aluminum-copper alloy powder is melted. When a portion of the aluminum-copper alloy powder is melted and another portion of the aluminum-copper alloy is not melted, spheroidization is caused.
Furthermore, the powder spreading thickness of the embodiment is 0.03-0.04 mm each time.
In order to ensure the comprehensive performance and compactness of the aluminum-copper alloy parts and prevent spheroidization and warping, two scanning modes, namely a grouping direction-changing mode (as shown in fig. 2) and a blocking direction-changing mode (as shown in fig. 3), can be considered. Scanning in an internal and external spiral mode can be considered when processing some parts with low density requirements, as shown in fig. 4, which is a schematic diagram of the internal and external spiral single-channel scanning direction.
Further, in this example, the scanning pitch is 0.05mm to 0.08mm when printing is performed.
The compactness of the aluminum-copper alloy sample piece under the parameters of 1:10, 3:10 and 1:5 of the ratio of the copper powder to the aluminum powder is found, wherein the aluminum-copper alloy sample piece mixed according to the ratio of 1:10 is the best in the aspects of surface quality and section smoothness, and the aluminum-copper alloy sample piece mixed according to the ratio of 1:5 is better in surface quality but has smaller gaps among sections. Although the spheroidization of the aluminum-copper alloy sample piece is small under the parameters of 1:10, 3:10 and 1:5 of the copper powder to the aluminum powder, the spheroidization is changed along with the continuous increase of the content of pure copper. The spheroidization phenomenon is allowed to occur in the laser rapid forming process and should be controlled to a smaller range as much as possible, because the spheroidization influences the comprehensive mechanical property of the aluminum-copper alloy sample piece.
When the ratio of the copper powder to the aluminum powder reaches 3:10, the spheroidization of the aluminum-copper alloy parts is serious. Particularly, the poor density and the serious spheroidization of the aluminum-copper alloy sample piece after being mixed according to the proportion can clearly see a plurality of small balls, which indicates that the content of the pure copper powder can indirectly influence the performance of the aluminum-copper alloy part, so that the aluminum-copper mixing proportion is strictly ensured in the actual processing process. This ratio is not suitable for processing aluminum bronze alloy powders.
Example 1 (1: 10 for copper powder and aluminum powder):
and establishing a 3-dimensional digital model of the sample to be printed, carrying out layered slicing processing on the model, and importing the model into 3D printing equipment.
200g of pure copper powder with the purity of more than 99.96 percent is weighed, and 2000g of pure aluminum powder with the purity of more than 99.5 percent is weighed, namely the ratio of the copper powder to the aluminum powder is 1: 10.
And (3) putting the weighed aluminum powder and copper powder into a vacuum drying oven for drying, wherein the drying temperature is 80-150 ℃, and the drying time is 25-40 minutes.
And mixing the aluminum powder and the copper powder, and carrying out atomization treatment to form aluminum-copper atomized powder.
Fixing the substrate in a forming cylinder, feeding the aluminum-copper atomized powder into a feeding device of selective laser melting equipment, introducing argon or nitrogen protective gas, and carrying out preheating treatment on the substrate.
Controlling the laser power to be adjusted to 225W, the scanning speed to be 800mm/s, the scanning interval to be 0.05mm and the powder spreading thickness to be 0.03mm, and carrying out laser three-dimensional scanning forming on the aluminum-copper atomized powder according to a processing model under the protection of inert gas. And after cooling, removing the floating powder on the surface to obtain a primary sample piece with the shape consistent with that of the CAD model.
Separating the primary sample piece from the substrate, carrying out solution treatment at 550 ℃ for 6 hours in a vacuum furnace, and then carrying out aging treatment at 150 ℃ for 10 hours to obtain a sample with good surface quality and high rigidity, hardness and wear resistance.
Example 2 (1: 5 ratio of copper powder to aluminum powder):
and establishing a 3-dimensional digital model of the sample to be printed, carrying out layered slicing processing on the model, and importing the model into 3D printing equipment.
400g of pure copper powder with the purity of more than 99.96 percent is weighed, and 2000g of pure aluminum powder with the purity of more than 99.5 percent is weighed, namely the ratio of the copper powder to the aluminum powder is 1: 5.
And (3) putting the weighed aluminum powder and copper powder into a vacuum drying oven for drying at the drying temperature of 100 ℃ for 35 minutes.
And mixing the aluminum powder and the copper powder, and carrying out atomization treatment to form aluminum-copper atomized powder.
Fixing the substrate in a forming cylinder, feeding the aluminum-copper atomized powder into a feeding device of selective laser melting equipment, introducing argon or nitrogen protective gas, and carrying out preheating treatment on the substrate.
And controlling the laser power to be adjusted to 325W, the scanning speed to be 850mm/s, the scanning interval to be 0.06mm and the powder spreading thickness to be 0.035mm, and carrying out laser three-dimensional scanning forming on the aluminum-copper atomized powder according to a processing model under the protection of inert gas. And after cooling, removing the floating powder on the surface to obtain a primary sample piece with the shape consistent with that of the CAD model.
Separating the primary sample piece from the substrate, carrying out solution treatment at 560 ℃ for 7 hours in a vacuum furnace, and carrying out aging treatment at 170 ℃ for 15 hours to obtain a sample with good surface quality and high rigidity, hardness and wear resistance.
Example 3 (3: 10 for copper and aluminum powders):
and establishing a 3-dimensional digital model of the sample to be printed, carrying out layered slicing processing on the model, and importing the model into 3D printing equipment.
600g of pure copper powder with the purity of more than 99.96 percent is weighed, and 2000g of pure aluminum powder with the purity of more than 99.5 percent is weighed, namely the ratio of the copper powder to the aluminum powder is 3: 10.
And (3) putting the weighed aluminum powder and copper powder into a vacuum drying oven for drying at the drying temperature of 150 ℃ for 40 minutes.
And mixing the aluminum powder and the copper powder, and carrying out atomization treatment to form aluminum-copper atomized powder.
Fixing the substrate in a forming cylinder, feeding the aluminum-copper atomized powder into a feeding device of selective laser melting equipment, introducing argon or nitrogen protective gas, and carrying out preheating treatment on the substrate.
The laser power is controlled to be adjusted to 400W, the scanning speed is 1000mm/s, the scanning interval is 0.08mm, and the powder spreading thickness is 0.04 mm. And under the protection of inert gas, carrying out laser three-dimensional scanning forming on the aluminum-copper atomized powder according to the processing model. And after cooling, removing the floating powder on the surface to obtain a primary sample piece with the shape consistent with that of the CAD model.
Separating the initial sample piece from the substrate, carrying out solution treatment at 600 ℃ for 10 hours in a vacuum furnace, and then carrying out aging treatment at 200 ℃ for 20 hours to obtain a sample with good surface quality and high rigidity, hardness and wear resistance.
The following table is provided for the compactness of the 3D printed part in different proportions and different parameters:
table 5: compactness result of aluminum-copper alloy parts under different parameters
The aluminum-copper alloy parts processed by the 3D printing technology need to be subjected to proper heat treatment, and can be subjected to heat preservation treatment if necessary, and the purpose of the method is mainly to improve the apparent hardness and the comprehensive mechanical property of the internal structure of the aluminum-copper alloy parts.
Through in-depth analysis, the hardness curve of the aluminum-copper alloy sample piece after the solution heat treatment is obtained, and in the heat treatment process, after the heat preservation time is 6 hours, the hardness of the aluminum-copper alloy standard piece reaches the peak value. The tensile strength of the aluminum-copper alloy parts is directly related to the length of solid solution time. In the aluminum-copper alloy heat treatment process, the solid solution time is strictly controlled, and the hardness, tensile strength and plasticity of the aluminum-copper alloy parts after heat treatment are improved. A good qualified mechanical part needs proper heat treatment, and is especially important for parts which are easy to process and difficult to machine of aluminum-copper alloy. The tensile strength is an important index for measuring the comprehensive performance of the parts, and when the tensile strength is increased, the pressure of the aluminum-copper alloy parts for resisting external loads is obviously improved. After the heat treatment, the internal structure performance of the aluminum-copper alloy part is obviously improved.
The quality of the aging treatment is directly related to the internal structure performance of the aluminum-copper alloy, and the proper selection of the proper heat treatment process in the processing is particularly obvious for improving the performance of the sample piece. The time is the premise of ensuring the comprehensive mechanical property of the aluminum-copper alloy. When the aging heat treatment time is gradually increased, the tensile strength of the aluminum-copper alloy sample piece is obviously increased, but when the aging heat treatment time reaches 15h, the tensile strength of the aluminum-copper alloy sample piece reaches a peak value.
Table 6: mechanical property results of non-heat-treated aluminum-copper alloy parts
| Proportioning | Tensile strength (MPa) | Hardness (HB) | Elongation percentage | Yield strength (MPa) |
| 1：10 | 105.00 | 86.21 | 29.80％ | (92.35) |
| 1：5 | 118.00 | 90.51 | 18.45％ | 98.54 |
| 3：10 | 123.00 | 98.24 | 20.10％ | 103.88 |
Table 7: mechanical property result of aluminum-copper alloy parts under different heat treatment parameters
| Proportioning | Tensile strength (MPa) | Hardness (HB) | Elongation percentage | Yield strength (MPa) |
| 1：10 | 130.00 | 89.50 | 25.50％ | 1(00.1)0 |
| 1：5 | 128.50 | 93.83 | 15.55％ | 105.50 |
| 3：10 | 156.00 | 105.56 | 18.68％ | 113.33 |
The research aims to overcome the defects of the traditional casting method and effectively improve the performance of the aluminum-copper parts. This experiment achieved good results. Particularly, in the aspect of avoiding the defects of shrinkage porosity, oxidation slag inclusion and the like, the laser rapid prototyping technology fully exerts the strong advantages thereof and effectively avoids the phenomenon.
By researching different factors influencing the rapid laser forming of the aluminum-copper alloy, the quality and the performance of the aluminum-copper alloy parts can be effectively controlled. The comprehensive mechanical property of the aluminum-copper alloy parts is improved remarkably by a heat treatment process.
The following conclusion is obtained by carrying out multi-factor analysis on parts processed by mixing aluminum-copper alloy powder with different proportions: the surface quality of the aluminum-copper alloy sample piece formed and processed by the laser rapid forming meets the actual requirement, and the compactness is high. After the parameters are optimized, the aluminum-copper alloy sample piece is obtained through processing, and the segregation degree of the internal structure is small. The novel laser rapid technology can effectively avoid the phenomena of shrinkage porosity, oxidation, slag inclusion and the like in the traditional method. After the processed aluminum-copper alloy sample piece is tested, the comprehensive mechanical property of the aluminum-copper alloy sample piece is obviously improved. The aluminum-copper alloy sample piece obtained by the SLM technology meets the actual requirements on tensile strength, hardness, yield strength, elongation and the like, and has good appearance. The aluminum-copper alloy sample piece processed by utilizing the laser rapid forming has the advantages that the toughness and the elongation are obviously improved after the solution heat treatment, and the effect is optimal particularly after the heat preservation time reaches 6 hours. In the laser rapid forming process, the mixing proportion of different elements has great influence on the forming of the aluminum-copper alloy, and the processed sample piece has better surface appearance and internal structure after being tested by using the aluminum-copper alloy mixed by the proportion of 10%.
In 3D printing processing, the influence of powder spreading thickness on aluminum-copper alloy forming is particularly obvious, and a spheroidization phenomenon can occur when the powder spreading thickness is continuously increased. In the aluminum-copper alloy processing process, due to the fact that the cooling speed of the sintered pure aluminum powder is too high, the powder mixed and sintered with aluminum and copper cannot be bonded to the substrate, and it is important for forming the aluminum-copper alloy that the substrate is fully preheated.
The aluminum-copper alloy sample piece processed by utilizing the laser rapid forming has the advantages that the hardness, the tensile strength and the like after aging heat treatment are obviously improved, and the effect is optimal particularly when the heat preservation time reaches 10 hours. Through deep analysis of the 3D printing technology process, it is found that too much or too little laser power can have an important influence on the forming of the aluminum-copper alloy test piece, when the laser power is increased, the powder layer is easy to be over-burnt, and when the laser power is too small, the powder is in an unmelted state, which is not favorable for the effective bonding of the powder.
In light of the foregoing description of the preferred embodiments according to the present application, it is to be understood that various changes and modifications may be made without departing from the spirit and scope of the invention. The technical scope of the present application is not limited to the contents of the specification, and must be determined according to the scope of the claims.
Claims (10)
1. A3D printing method of aluminum-copper alloy is characterized by comprising the following steps:
s1 digital-to-analog slicing: generating a 3D digital model of a sample to be printed according to a part model, slicing the 3D digital model to form an image sequence which can be identified by a 3D printer, wherein each image in the image sequence represents one layer of the 3D digital model, and controlling a 3D printing track according to a slicing path of the image sequence of the digital model;
s2 powder atomization treatment: mixing copper powder and aluminum powder in a certain mass ratio, and carrying out atomization treatment to form aluminum-copper atomized powder;
s3 aluminum bronze powder 3D printing: introducing inert protective gas into a printing chamber of the 3D printer, preheating a matrix, setting powder paving parameters and printing parameters of the 3D printer, controlling a powder paving roller to pave the aluminum copper atomized powder in the step S2 according to the image sequence and the powder paving parameters in the step S1, and controlling the fiber laser to melt the aluminum copper powder layer by layer according to the 3D printing track and the printing parameters in the step S1 to perform layer-by-layer accumulation printing to obtain an initial sample;
s4 primary sample heat treatment: and carrying out solid solution aging heat treatment on the initial sample to obtain a printing sample.
2. The method of 3D printing of aluminum bronze alloy according to claim 1, characterized in that:
and step S2, mixing the copper powder and the aluminum powder in a mass ratio of 1: 10-1: 5.
3. The method of 3D printing of aluminum bronze alloy according to claim 1, characterized in that:
the powder atomization treatment in the step S2 is to crush the molten aluminum-copper metal liquid flow into liquid drops by utilizing high-pressure Ar airflow, and the aluminum-copper atomized powder is obtained after condensation; the high-pressure Ar airflow pressure is 1.5-2.5 MPa.
4. The method of 3D printing of aluminum bronze alloy according to claim 3, characterized in that:
the particle size of the aluminum-copper atomized powder after screening is 20-40 mu m.
5. The method of 3D printing of aluminum bronze alloy according to claim 1, characterized in that:
step S3, the inert protective gas is Ar gas; the base body is a 6061 aluminum alloy base body, the preheating base body is preheated by laser, the preheating temperature is 60-70 ℃, the preheating is carried out for 4-7 seconds every time, and the preheating is carried out for 3-4 times.
6. The method of 3D printing of aluminum bronze alloy according to claim 1, characterized in that:
and S3, wherein the powder paving thickness of the powder paving parameters in each time is 0.03-0.04 mm.
7. The method of 3D printing of aluminum bronze alloy according to claim 1, characterized in that:
and step S3, the printing power of the printing parameters is 225-400W, the scanning speed is 800-1000 mm/S, and the scanning distance is 0.05-0.08 mm.
8. The method of 3D printing of aluminum bronze alloy according to claim 1, characterized in that:
step S3 also includes before 3D printing of aluminium bronze powder: and (3) drying the aluminum copper powder in a vacuum drying oven at the drying temperature of 80-150 ℃ for 25-40 minutes.
9. The method of 3D printing of aluminum bronze alloy according to claim 1, characterized in that:
and S4, performing solution aging treatment at the solution treatment temperature of 550-600 ℃, and performing delayed heat preservation for 6-10 hours.
10. The method of 3D printing of aluminum bronze alloy according to claim 1 or 9, characterized in that:
and S4, carrying out solid solution aging treatment at the temperature of 150-200 ℃ for 10-20 hours.
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