Beyond the "black technology" of food, clothing, housing and transportation, textiles can also go to heaven and earth!

On February 22, the Long March 8 Yao-3 carrier rocket arrived at the Wenchang Space Launch Center in China, and will be used to carry out the launch mission of the Queqiao-2 relay satellite of the fourth phase of the lunar exploration project. At present, the rocket is carrying out various assembly and testing work at the launch site. Previously, in January and early February of this year, the Chang'e-6 mission probe and the Queqiao-2 satellite had arrived at the launch site in advance, and were also undergoing various pre-launch test preparations. According to the plan, in the first half of this year, my country will successively launch Queqiao-2 and Chang'e-6. Chang'e-6 is to launch a probe to the back of the moon to collect lunar soil and then bring it back to Earth for research. What is the role of Queqiao-2? Because there is no direct communication between the back of the moon and the earth, the Queqiao-2 relay satellite must be launched first. It can build a "Queqiao Bridge" for signal communication between the Chang'e-6 probe and the ground station that will go to the back of the moon to collect samples in the future.

Before Queqiao-2, more than five years ago, a Queqiao relay satellite provided communication relay services for Chang'e-4's landing and exploration mission on the far side of the moon. The most notable feature of Queqiao is that it has such a "golden umbrella", called a large onboard deployable antenna. Through this "golden umbrella", communication between the earth and the far side of the moon is achieved. In the laboratory of Donghua University in Shanghai, there is a scaled-down example of the umbrella-shaped antenna of the Queqiao relay satellite. This golden umbrella is actually made of woven metal.

In the laboratory of the School of Textiles of Donghua University, the reporter saw this "big umbrella" with a thin layer of yellow metal mesh on the ribs. Experts said that the metal mesh is a key component of the satellite-borne deployable antenna to reflect electromagnetic waves. It can be deployed during the launch into orbit. The key to its ability to deploy the reflective surface lies in the warp knitting technology.

Chen Nanliang, professor at Donghua University and director of the Ministry of Education's Industrial Textile Engineering Research Center: When the rocket is launched, it is retracted inside the rocket. After reaching orbit, it slowly unfolds the satellite reflector into a mesh antenna through the unfolding mechanism, so we call it a deployable antenna. It is flexible, so it can be unfolded, so we need to use textile weaving technology to form such a fabric. The metal mesh on the satellite-borne deployable antenna is made of metal molybdenum wire. In order to increase its performance, experts have done more coating and processing on the extremely fine molybdenum wire.

Chen Nanliang, professor at Donghua University and director of the Industrial Textile Engineering Research Center of the Ministry of Education: The raw material we use is called gold-plated molybdenum wire, which is molybdenum wire with gold plated on the surface, because the reflectivity of gold is very good.

Reporter: When unfolded, the metal wire is very thin. Does the weaving require some special techniques to make it so even?

Chen Nanliang, professor at Donghua University and director of the Ministry of Education's Industrial Textile Engineering Research Center: These are some of our key technologies. First of all, the molybdenum wire is very thin, about 15 to 30 microns, less than a quarter of the diameter of a hair. So drawing it is very difficult, and the surface is also gold-plated. After gold plating, we need to maintain a certain fastness. We doped some organic elements, which not only improves the toughness of the metal raw materials, but also makes its surface more affinity. Therefore, some process improvements make the gold-plated molybdenum wire very strong during the weaving process.

Chen Nanliang, professor at Donghua University and director of the Ministry of Education's Industrial Textile Engineering Research Center: The weaving process is relatively delicate and complicated. First, we have to do the doubling. Because it is too thin, we invented a doubling and twisting technology, where three metal wires are twisted together, and the structure is very stable.

Experts told reporters that metal molybdenum wire is very soft, and single-strand molybdenum wire is too thin and not strong enough, so three or four molybdenum wires are usually used together to weave a metal mesh. However, now, with the trend of large-scale satellites, the antenna reflector surface is getting bigger and bigger, which is conducive to communication between the earth and the sky. But the larger the area, the heavier the weight will be. How can the antenna be made big and light? The research team has innovated weaving technology, and now single-strand molybdenum wire can be used to weave larger and lighter metal meshes. The largest is about the size of a basketball court. Since 2017, the Donghua University Industrial Textile Flexible Structural Materials Innovation Team has begun to tackle the metal molybdenum wire monofilament warp knitting technology. After 5 years of hard work, the innovative "micro-tension" warp knitting technology and equipment have been developed, which greatly reduced the weight of the new antenna reflector.

Jiang Jinhua, professor of the School of Textiles at Donghua University: Compared with the original, it may be 1/3 or 1/4 lighter, the cost may be lower, and the weight is also very low. Therefore, the lightest net may weigh less than 20 grams per square meter.

The reflective surface of the Land Exploration No. 4 01 satellite, which was launched in August 2023, is woven with extremely fine metal molybdenum wire monofilaments. The unfolding area of ​​its large ring-shaped antenna is close to the area of ​​a basketball court, which greatly improves the reflective surface area and communication capability of the high-orbit satellite's deployable antenna.

Jiang Jinhua, professor of the School of Textiles at Donghua University: In the future, antennas may become larger and larger, possibly reaching the hundred-meter or kilometer level, which requires the mesh structure of the single wire to meet the application of ultra-large satellite antennas. Communications are becoming more and more frequent, requiring more and more data throughput. If the caliber is too small, it will not meet the frequent high-throughput data transmission. Now we are not only making molybdenum wire, but also other raw materials, and are also making some trial applications.

On January 17, the Tianzhou-7 cargo spacecraft delivered a batch of daily necessities and experimental equipment to the space station. It turns out that the solar wing substrate of the Tianzhou cargo spacecraft is also woven, and its fiberglass mesh structure looks like a tennis racket.

Fiberglass mesh structure is lightweight and resistant to oxidation

According to reports, the Tianzhou cargo spacecraft uses a semi-rigid solar wing, which has a carbon fiber frame and a glass fiber mesh in the middle, similar to a tennis racket, on which the solar cells are hooked. This glass fiber mesh structure is lightweight and has stronger protection against atomic oxygen and plasma in the low-orbit space environment.

Chen Nanliang, professor at Donghua University and director of the Ministry of Education's Industrial Textile Engineering Research Center: There is a large amount of atomic oxygen in space, which has a very strong oxidizing ability, so generally organic polymer materials are oxidized very strongly. Therefore, we need to choose a material with a very high antioxidant ability, so we chose the inorganic material glass fiber. Glass fiber has the advantages of being antioxidant and light in weight. But it is very difficult to weave a net with glass fiber.

Chen Nanliang, professor at Donghua University and director of the Ministry of Education's Industrial Textile Engineering Research Center: Glass fiber also has a very big weakness, its weaving performance is very poor because it is very brittle. Textile materials are closely related to the fineness of the fiber. The finer the fiber, the stronger its softness. After being twisted and combined, it becomes a very thick raw material, which can be achieved through weaving.

Chen Nanliang, professor at Donghua University and director of the Ministry of Education's Industrial Textile Engineering Research Center: It has another advantage, it is light, and it is all mesh, and the solar cells are hooked on it. Glass fiber coated with resin is more resistant to the space environment. After the glass fiber is woven into the substrate of the solar sail panel, it will be coated with resin to improve its performance.

Jiang Jinhua, professor of the School of Textiles at Donghua University: The main purpose of applying resin is to make the surface smoother and also to protect it. Because resins like silicone are more resistant to space environments, and their stability and wear resistance can also be improved, which can greatly improve the overall performance.

The use of new materials and new weaving techniques have made the word textile more than just clothing. For example, the "metal mesh for satellite antennas" mentioned earlier has been used on many satellites, including the Queqiao relay satellite, Beidou navigation satellite, and mobile communication satellite. Textiles are not only increasingly used in the aerospace field, but also have great potential in large aircraft manufacturing and even in the field of biological applications.

Chen Nanliang, professor at Donghua University and director of the Ministry of Education's Industrial Textile Engineering Research Center: Textiles are a type of material, and may be a special type of material, such as aerospace. In the aerospace field, for example, deployable antennas need to be large-scale. Steel is a hard material and cannot be made so large, nor can it be transported. Therefore, a soft material is needed that can be folded up and then unfolded when it is used. Only textiles can be made into such soft things.

Communication barrier-free mobile phone connected to satellite

Chen Nanliang, professor at Donghua University and director of the Ministry of Education's Industrial Textile Engineering Research Center: Large deployable antennas are mainly used to enhance the exchange of data between high-performance satellites and ground. They are mainly used in some communication satellites and navigation satellites, and are also useful in Beidou. In communications, there is the Tiantong satellite, which also uses a reflective antenna. The satellite can communicate with our mobile phones, and this antenna plays a very decisive role.

Biological application organ vascular patch

Chen Nanliang, professor at Donghua University and director of the Ministry of Education's Industrial Textile Engineering Research Center: Textiles still have many application areas to expand, such as the biomedical field. Human organs, blood vessels, and patches are all closely related to textile technology and textile products.

Carbon fiber fabrics for large aircraft

Chen Nanliang, professor at Donghua University and director of the Ministry of Education's Industrial Textile Engineering Research Center: C919 has already used our country's carbon fiber fabrics, and C929 will use even more. There are many aerospace fields, and rigid materials made of carbon fiber materials are already very common. The application of flexible textile materials has just begun, so our textile technology also has a very bright future.

(Source: CCTV.com, Jimu News)