Method for selecting excellent lunar soil heating temperature during melting additive manufacturing

Abstract

The invention belongs to the technical field of lunar surface lunar soil additive manufacturing, and provides a selection method for a better lunar soil heating temperature during melting additive manufacturing. The method comprises the following steps: placing a simulated lunar soil sample on the surface of a substrate, heating, and measuring the contact angle between the simulated lunar soil sample and the substrate at different heating temperatures; and selecting the corresponding heating temperature obtained in the previous step when the contact angle is less than or equal to 90 degrees to obtain the heating temperature of lunar soil melting additive manufacturing. According to the method, the optimal heating temperature for lunar soil melting additive manufacturing is selected by detecting the contact angle, repeated experiments are not needed, the experiment frequency and time consumption are reduced, the experiment cost is reduced, meanwhile, the method is further suitable for selecting the optimal heating temperature of lunar soil in different areas of the moon during melting additive manufacturing, and universality is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of lunar soil additive manufacturing, and in particular to a method for selecting an optimal heating temperature of lunar soil during melt additive manufacturing. Background Art

[0002] In the additive manufacturing of lunar soil buildings on the lunar surface, existing studies have proved that using additive manufacturing technology on the moon to make lunar soil structures is a feasible method. In the work of lunar soil melting additive manufacturing, there is little research on the appropriate heating temperature in the lunar soil melting printing process. According to the current additive manufacturing experiments, the selection of process parameters is determined by the quality of the printed products, and the quality of the products manufactured by lunar soil melting additive manufacturing is determined by the contour morphology and surface roughness of the interlayer molten material.

[0003] At present, most of the research is aimed at the printing process of a certain lunar soil and the research on its optimal printing process parameters. One specific research method is to simulate the computer's molten additive manufacturing by inputting the process parameter values, and analyze the morphology of the molten pool and the combination of particles. The other is to test the strength of the printed structure under different process parameters through a large number of experiments. However, when using the simulation method to study, due to the complex environmental conditions on the lunar surface, it is impossible to accurately couple the various conditions of the manufacturing environment, so the simulation is more difficult; at the same time, because the lunar soil is a mixture, the different mineral content leads to different values ​​of the thermophysical parameters of the lunar soil, and the properties of the lunar soil in the simulation are different, resulting in the lack of universality of the printing results obtained by the simulation. When using the experimental method to study, the lunar soil material needs to be compared once or twice under each printing parameter to reduce the experimental error, which requires a large number of repeated experiments and takes a lot of time. In addition, since the lunar soil is used as the experimental material, the lunar soil is relatively rare on the earth. In order to relatively reduce the experimental cost, simulated lunar soil is used as the experimental material, but the cost of conducting a large number of repeated experiments on simulated lunar soil is high.

[0004] In addition, in the in-situ construction on the moon, the lunar regions are divided into high regions, mare regions and polar regions. The mineral composition types of the lunar soil in different regions are roughly the same. The difference is that the content of each component in the lunar soil in different regions is different, which in turn affects the melting temperature of the lunar soil in different regions. Therefore, the existing experimental research is mostly aimed at the research on the better process parameters in the lunar soil melting additive manufacturing in specific regions, which is not widely referenced.

[0005] In summary, how to provide a method for selecting the optimal heating temperature of lunar soil during melt additive manufacturing that requires fewer experiments, less time, lowers costs, and is suitable for use in different regions of the moon is an urgent problem to be solved in this field. Summary of the invention

[0006] In view of this, the present invention provides a method for selecting the optimal heating temperature of lunar soil during melt additive manufacturing, so as to solve the problems of existing methods for selecting the heating temperature in lunar soil melt additive manufacturing, such as large number of experiments, long time consumption, high cost and not being suitable for lunar soil melt additive manufacturing of lunar soil in different regions of the moon.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] The present invention provides a method for selecting an optimal heating temperature of lunar soil during melt additive manufacturing, comprising the following steps:

[0009] (1) Placing a simulated lunar soil sample on the surface of a substrate, heating it, and measuring the contact angle between the simulated lunar soil sample and the substrate at different heating temperatures;

[0010] (2) Select the heating temperature corresponding to the contact angle ≤90° obtained in step (1), that is, the heating temperature for lunar soil melt additive manufacturing.

[0011] Preferably, the heating temperature range in step (1) is 500-1300°C; and the contact angle between the simulated lunar soil sample and the substrate is detected once every 50-200°C within the heating temperature range.

[0012] Preferably, in step (1), the matrix comprises one of alumina and graphite.

[0013] Preferably, the method for preparing the simulated lunar soil sample in step (1) is to compact the simulated lunar soil to obtain the simulated lunar soil sample.

[0014] Preferably, the simulated lunar soil is basaltic simulated lunar soil, the particle size of the basaltic simulated lunar soil is 5 to 1000 μm, and the median particle size is 60 to 75 μm; the basaltic simulated lunar soil includes the following components in mass percentage:

[0015] SiO245~50%, Al2O315~20%, CaO 10~15%, FeO 5~10%, MgO 5~10%, TiO21~3%, Na2O 0.5~1%, MnO 0~0.3%, Cr2O30.1~0.5%, K2O 0.3~0.7%, P2O50.5~0.7%.

[0016] The present invention also provides an application of a heating temperature determined by the above-mentioned heating temperature selection method in in-situ melting additive manufacturing of lunar soil.

[0017] It can be seen from the above technical solution that compared with the prior art, the present invention has the following beneficial effects:

[0018] The present invention characterizes the wettability of the simulated lunar soil sample and the substrate by detecting the contact angle between the simulated lunar soil sample and the substrate. The smaller the contact angle, the better the wettability between the simulated lunar soil sample and the substrate. The better the wettability, the better the bonding quality, contour morphology and surface roughness between the material layers of the lunar soil melt additive manufacturing building. Therefore, the present invention creatively selects the optimal heating temperature for lunar soil melt additive manufacturing based on the contact angle between the simulated lunar soil sample and the substrate to prepare the lunar soil melt additive manufacturing building with the best quality, which can greatly reduce the number of experiments for selecting the optimal heating temperature, reduce time consumption, and reduce experimental costs. In addition, since the wettability characterized by the contact angle of the lunar soil in different regions of the moon to the same substrate is the same, the method of the present invention can quickly determine the optimal heating temperature of the lunar soil in different regions of the moon during melt additive manufacturing during in-situ construction on the moon, and has wide applicability. DETAILED DESCRIPTION

[0019] The present invention provides a method for selecting an optimal heating temperature of lunar soil during melt additive manufacturing, comprising the following steps:

[0020] (1) Placing a simulated lunar soil sample on the surface of a substrate, heating it, and measuring the contact angle between the simulated lunar soil sample and the substrate at different heating temperatures;

[0021] (2) Select the heating temperature corresponding to the contact angle ≤90° obtained in step (1), that is, the heating temperature for lunar soil melt additive manufacturing.

[0022] In the present invention, the heating temperature range in step (1) is 500-1300°C, preferably 600-1250°C, further preferably 800-1200°C, and more preferably 1000-1150°C; within the heating temperature range, the contact angle between the simulated lunar soil sample and the substrate is detected once every 50-200°C, preferably every 80-170°C, further preferably every 100-150°C, and more preferably every 110-130°C.

[0023] In the present invention, the substrate in step (1) preferably comprises one of alumina and graphite.

[0024] In the present invention, the method for preparing the simulated lunar soil sample in step (1) is to compact the simulated lunar soil to obtain the simulated lunar soil sample.

[0025] In the present invention, the method for preparing the simulated lunar soil sample preferably comprises adding the simulated lunar soil into a mold, compacting the simulated lunar soil using mechanical external force or manual pressure, and obtaining the simulated lunar soil sample.

[0026] In the present invention, the structure of the simulated lunar soil sample is a quadrangular prism structure.

[0027] In the present invention, the simulated lunar soil is basaltic simulated lunar soil, the particle size of the basaltic simulated lunar soil is 5 to 1000 μm, preferably 20 to 800 μm, more preferably 40 to 500 μm, and more preferably 50 to 300 μm; the median particle size is 60 to 75 μm, preferably 62 to 73 μm, more preferably 65 to 70 μm, and more preferably 68.71 μm;

[0028] In the present invention, the basaltic simulated lunar soil includes the following components in percentage by mass:

[0029] SiO245~50%, Al2O315~20%, CaO 10~15%, FeO 5~10%, MgO 5~10%, TiO21~3%, Na2O 0.5~1%, MnO 0~0.3%, Cr2O30.1~0.5%, K2O 0.3~0.7%, P2O50.5~0.7%. .

[0030] In the present invention, the mass percentage of SiO2 is preferably 46-49%, more preferably 47-48%, and more preferably 47.89%; the mass percentage of Al2O3 is preferably 16-18%, more preferably 16.5-17%, and more preferably 16.92%; the mass percentage of CaO is preferably 10.5-13%, more preferably 11-12%, and more preferably 11.23%; the mass percentage of FeO is preferably 7-10%, more preferably 8-10%, and more preferably 9.99%; the mass percentage of MgO is preferably 6-9.5%, more preferably 8-9.4%, and more preferably 9.36%; the mass percentage of TiO2 is preferably 1.5-2.5% , further preferably 1.7-2%, more preferably 1.84%; the mass percentage of the Na2O is preferably 0.7-0.95%, further preferably 0.8-0.9%, more preferably 0.89%; the mass percentage of the MnO is preferably 0.1-0.25%, further preferably 0.15-0.2%, more preferably 0.18%; the mass percentage of the Cr2O3 is preferably 0.2-04%, further preferably 0.25-0.3%, more preferably 0.26%; the mass percentage of the K2O is preferably 0.4-0.6%, further preferably 0.45-0.55%, more preferably 0.5%; the mass percentage of the P2O5 is preferably 0.55-0.65%, more preferably 0.6%.

[0031] In the present invention, the contact angle measurement method in step (1) is preferably to use an infrared camera and a camera to record the heating temperature of the simulated lunar soil sample and the contour change photos of the simulated lunar soil sample at different heating temperatures, and then use image recognition technology to measure the contact angle in the contour change photos of the simulated lunar soil sample at different heating temperatures to obtain the contact angle between the simulated lunar soil sample and the substrate at different heating temperatures.

[0032] The present invention also provides an application of the heating temperature determined by the above-mentioned heating temperature selection method in the in-situ melting additive manufacturing of lunar soil.

[0033] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0034] Example 1

[0035] Basaltic simulated lunar soil material with unscreened particle size (purchased from Jilin University) was selected, compacted into a quadrangular prism structure and placed on a graphite substrate. It was heated by a heating source to test the contact angle between the simulated lunar soil sample and the substrate at different temperatures. First, the temperature range was set at 500-900°C, and the temperature was gradually increased from 500°C with a temperature increase gradient of 200°C. The contact angle between the simulated lunar soil sample and the substrate was tested every 200°C. When the temperature rose to 900°C, the temperature range was set at 900-1100°C with a temperature increase gradient of 100 The temperature was gradually increased by 100°C, and the contact angle between the simulated lunar soil sample and the substrate was detected every 100°C. When the temperature rose to 1100°C, the temperature range was set at 1100-1300°C, and the temperature was gradually increased with a temperature gradient of 50°C, and the contact angle between the simulated lunar soil sample and the substrate was detected every 50°C until the temperature rose to 1300°C. From the test results, it was found that when the temperature was between 1200 and 1250°C, the contact angle was ≤50°, and the interlayer bonding ability was good. It was obtained that the heating temperature for lunar soil melt additive manufacturing was 1200-1250°C.

[0036] Example 2

[0037] A basalt simulated lunar soil material with a particle size of 75 to 100 μm (purchased from Jilin University) was selected, compacted into a quadrangular prism structure and placed on a graphite substrate. The material was heated by a heating source to test the contact angle between the simulated lunar soil sample and the substrate at different temperatures. First, the temperature range was set at 500 to 900 °C, and the temperature was gradually increased from 500 °C by a temperature increase gradient of 200 °C. The contact angle between the simulated lunar soil sample and the substrate was tested every 200 °C. When the temperature rose to 900 °C, the temperature range was set at 900 to 1100 °C with a temperature increase gradient of 200 °C. The temperature was gradually increased by 100°C, and the contact angle between the simulated lunar soil sample and the substrate was detected every 100°C. When the temperature rose to 1100°C, the temperature range was set at 1100-1300°C, and the temperature was gradually increased with a temperature gradient of 50°C, and the contact angle between the simulated lunar soil sample and the substrate was detected every 50°C until the temperature rose to 1300°C. From the test results, it was found that when the temperature was between 1150 and 1200°C, the contact angle was ≤50°, and the interlayer bonding ability was good. The heating temperature for lunar soil melt additive manufacturing was 1150-1200°C.

[0038] Example 3

[0039] A basalt simulated lunar soil material with a particle size of 44 to 55 μm (purchased from Jilin University) was selected, compacted into a quadrangular prism structure and placed on a graphite substrate. The material was heated by a heating source to test the contact angle between the simulated lunar soil sample and the substrate at different temperatures. First, the temperature range was set at 500 to 900 °C, and the temperature was gradually increased from 500 °C by a temperature increase gradient of 200 °C. The contact angle between the simulated lunar soil sample and the substrate was tested every 200 °C. When the temperature rose to 900 °C, the temperature range was set at 900 to 1100 °C with a temperature increase gradient of 200 °C. The temperature was gradually increased by 100°C, and the contact angle between the simulated lunar soil sample and the substrate was detected every 100°C. When the temperature rose to 1100°C, the temperature range was set at 1100-1300°C, and the temperature was gradually increased with a temperature gradient of 50°C, and the contact angle between the simulated lunar soil sample and the substrate was detected every 50°C until the temperature rose to 1300°C. From the test results, it was found that when the temperature was between 1150 and 1200°C, the contact angle was ≤50°, and the interlayer bonding ability was good. The heating temperature for lunar soil melt additive manufacturing was 1150-1200°C.

[0040] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for selecting the optimal heating temperature of lunar soil during melt additive manufacturing, characterized in that: The steps include: (1) Placing a simulated lunar soil sample on the surface of a substrate, heating it, and measuring the contact angle between the simulated lunar soil sample and the substrate at different heating temperatures; (2) Select the heating temperature corresponding to the contact angle ≤90° obtained in step (1), that is, the heating temperature for lunar soil melt additive manufacturing.

2. The method for selecting the optimal heating temperature of lunar soil during melt additive manufacturing according to claim 1 is characterized in that: The heating temperature range in the step (1) is 500-1300° C.; the contact angle between the simulated lunar soil sample and the substrate is detected once every 50-200° C. within the heating temperature range.

3. The method for selecting the optimal heating temperature of lunar soil during melt additive manufacturing according to claim 2 is characterized in that: In the step (1), the substrate comprises one of alumina and graphite.

4. The method for selecting the optimal heating temperature of lunar soil during melt additive manufacturing according to claim 3 is characterized in that: The method for preparing the simulated lunar soil sample in step (1) is to compact the simulated lunar soil to obtain the simulated lunar soil sample.

5. The method for selecting the optimal heating temperature of lunar soil during melt additive manufacturing according to claim 4 is characterized in that: The simulated lunar soil is basaltic simulated lunar soil, the particle size of the basaltic simulated lunar soil is 5 to 1000 μm, and the median particle size is 60 to 75 μm; The basaltic simulated lunar soil includes the following components in percentage by mass: SiO245~50%, Al2O315~20%, CaO 10~15%, FeO 5~10%, MgO 5~10%, TiO21~3%, Na2O 0.5~1%, MnO 0~0.3%, Cr2O30.1~0.5%, K2O 0.3~0.7%, P2O50.5~0.7%.

6. Application of the heating temperature determined by the method for selecting the heating temperature described in any one of claims 1 to 5 in the in-situ melting additive manufacturing of lunar soil.