China successfully completes first space “3D printing”

The new generation of manned spacecraft test ship also carried a “3D printer”, this is China’s first space 3D printing experiment, but also the first international in space to carry out continuous fiber-reinforced composite materials 3D printing experiments. So what did it print on the ship?

This time in the test ship carried a Chinese independently developed “composite space 3D printing system”, the researchers installed this “3D printer” in the test ship return module, during the flight the system independently completed the continuous fiber-reinforced composite material sample printing, and verified the microgravity environment composite material 3D printing of scientific experimental objectives.

It is understood that continuous fiber-reinforced composite materials are the main materials of spacecraft structure at home and abroad, low density and high strength, and carry out research on the technology of 3D printing of composite material space is of great significance for the long-term operation of the space station in orbit and the development space of super-large structure in orbit.

On May 5, the Long March V B (hereinafter referred to as “Long 5B”) successfully launched a new generation of Manned Spacecraft test ship into a predetermined orbit at the Wenchang Space Launch Site in Hainan. In this mission, the space application system led by the Chinese Academy of Sciences arranged three scientific tests, such as in-orbit fine molding experiment, material friction behavior experiment, microgravity measurement experiment, etc. in the new spacecraft test ship, which will carry out forward-looking scientific research and technical verification for the future operation of China’s space station construction and towards a more distant deep space.

In the course of human exploration into space, the “supply line problem” of equipment and materials has been preventing people from flying farther into space. With the rapid development of space 3D printing technology, it is possible to achieve “self-sufficiency” of spacecraft components. In 2014, NASA’s world’s first space 3D printer arrived at the International Space Station, kicking off human “space manufacturing.” According to the introduction, in order to further enhance the manufacturing accuracy and expand the material pedigree that can be used for space manufacturing, the “in-orbit fine molding experimental device” developed by the research team of the Space Application Center of the Chinese Academy of Sciences will be the first time in the world using stereoscopic lithography 3D printing technology for the metal/ceramic composite materials for micron-level precision in-orbit manufacturing. Space weightlessness environment is one of the main challenges facing stereolithography technology, ordinary printing slurry can not maintain a stable form under weightlessness conditions, will climb the wall caused the fluid surface ups and downs affect printing. Through domestic and foreign weightless aircraft, the team has carried out hundreds of experiments in microgravity environment, analyzed the rheological behavior and internal mechanism under weightlessness conditions, used chemical and physical methods to optimize the slurry from liquid to soft material form, soft material-specific yield stress in the weightlessness conditions to resist deformation, inhibit the climbing wall, and under the action of higher shear force, it can restore good flow, to ensure smooth printing.

As we all know, there must be wear and tear in motion, such as people’s common mechanical motion mechanism, its components due to relative motion must occur friction and wear, the formation of a friction product called grinding chips, often accumulated near the moving site and may be contaminated with the surrounding surface, in the satellite, spacecraft and space station this phenomenon can not be avoided. Therefore, based on the purpose of reducing wear of moving parts and extending the service life of moving parts, it is often necessary to lubricate the frictional surface of the moving part with lubricant, grease or solid lubrication. Developed by the Space Application Center of the Chinese Academy of Sciences in conjunction with the Lanzhou Institute of Chemical Physics, the “Material Friction Behavior Experimental Device” will study the wetting behavior of liquid lubrication materials and the migration behavior of solid friction products in microgravity environment, analyze the effect of solid surface state on the leaching of liquid lubrication materials by observing the wetting phenomenon of different types of lubricants, reveal the action law of space environmental factors, especially microgravity environment, on the wetting behavior of lubricants, and guide the new surface modification techniques that can be applied to space moving parts. Support for the design and development of long-life lubrication technology. At the same time, by examining the migration phenomenon of grinding chips in microgravity environment, studying the effect of space environmental factors on the grinding debris drift, exploring the distribution state of crumbs in the space microgravity environment, pushing the driving mechanism of the grinding drift in microgravity environment, and providing guiding significance for the study of grinding and binding of the subsequent long-life motion mechanism during orbit operation.

When manned spacecraft in orbit, it will be disturbed by various forces other than the earth’s gravity, such as atmospheric resistance, solar radiation light pressure, gravity gradient effect, orbit maneuvering, attitude control, equipment operation and occupant activities, so as to achieve a complete “weightlessness” state, but a “microgravity” environment. “Microgravity” is a deviation from weightlessness, and its size can be measured by the acceleration value of the interference force of the spacecraft. In order to grasp and eliminate the effect of various interferences on the experimental load of spacecraft internal science, and to provide the required high microgravity level experimental environment for scientific experiments, it is necessary to accurately measure the microgravity level of scientific experimental load. By the Chinese Academy of Sciences Space Application Center jointhua University of Science and Technology, China Aerospace Science and Technology Group 33 developed the “microgravity measurement experimental device” will be a variety of types of micro-vibration accelerometer synking accelerometer in the same equipment for acceleration measurement capability test and in-orbit verification, but also the domestic high-precision micro-mechanical system electrostatic suspension accelerometer for the first time in orbit flight, will be for China’s space station period to carry out high-sensitivity microgravity measurement technology and high microgravity control technology in advance technical verification and technology storage.