In the aerospace field of "weighing every ounce and conquering gold", the application of 3D printing technology makes the satellite "slimmer" and "richer". On December 3, at the Second International Conference on Advanced Research in Additive Manufacturing held in Nanjing, the reporter of Science and Technology Daily learned that Nanjing University of Technology has applied 3D printing technology to more than 10 micro nano satellites that have been launched. Additive manufacturing, commonly known as 3D printing, is an emerging manufacturing technology based on digital models to stack materials layer by layer to produce physical goods. It is an important part of advanced manufacturing. "Look at this micro nano satellite model, which is printed in 3D. Such a large satellite is generally used for space science experiment verification." Liu Tingting, deputy dean of the School of Mechanical Engineering of Nanjing University of Technology, said. She holds a 10 cubic centimeter satellite model, in which various components with different functions are embedded in the structure. "The structural materials in satellites have no function. They are similar to TV casings. They just assemble various components. Every time the weight of a satellite increases, its cost will increase a lot. If the structural materials can be lighter, it can reduce costs, provide a basis for mass production of satellites, and carry more satellite loads and conduct more space tests." Liu Tingting introduced that the traditional satellite manufacturing mode is the separation, manufacturing, reassembly and integration of various modules inside the satellite. However, her team proposed that the conductive lines of micro/nano satellites should be generated inside the structure, and then some functional loads should be embedded, which will integrate the circuits, components and functional materials of the satellite and enable the integrated 3D printing and manufacturing of "structure circuit device". "The topology design, lattice design and other lightweight design technologies of the integrated 3D printing technology can be rearranged on the internal structure of the satellite, so that the satellite can be lightweight." Liu Tingting told the reporter that the integrated micro nano satellite developed by 3D printing can reduce its volume by more than 30% and increase its functional density by more than 30%. Liu Tingting said that in the future, we will use multiple robots to print satellites, one robot printing circuit, one robot printing structure, and one robot embedded device, and finally they will be manufactured in an integrated way. The original satellite structure accounts for about 15% - 20%, or even 25%, and is expected to fall below 10% or even lower in the future. How difficult is it for satellites to "slim down"? Liu Tingting revealed that the complex structure of the satellite should be lightened first, "but at the same time, the satellite should also be able to achieve a certain impact resistance, because the rocket will have a lot of vibration during the launch process, and the impact on satellite components and structures is very strong. The satellite should be able to bear a huge impact, which requires high design requirements." The severe space environment also challenges the stability of satellite performance. "The space environment is very complex. It can reach 100 degrees centigrade at high temperatures and 100 degrees centigrade below zero at low temperatures. In such an environment, the structural components of satellites should be able to withstand extreme temperatures and space radiation, which also puts forward high requirements for the performance of 3D printing materials." Liu Tingting said. (Liu Xinshe)