Lu Jian, inventor of ceramic 4D printing: The most important thing to do research is originality

Xinhua News Agency, Hong Kong, August 25 (Reporter Zhang Yashi LinNing) "The most important thing about doing research is originality, and our invention was realized by no one before, and it is subversive." Lu Jian, Chair Professor of Mechanical Engineering at city university of Hong Kong, led his team to achieve the world's first ceramic 4D printing, and the research results were published in the academic journal Science Advances on August 17.

After more than two years of time, the research team of CityU has successfully developed ceramic 4D printing technology and "ceramic ink", which can print ceramics with both strong and complex shapes, and strengthen the application of ceramics in high-tech fields.

"The breakthrough of this invention lies in the overall concept and implementation plan, and in the design of the 'ink'." In an exclusive interview with reporters a few days ago, Lu Jian said that the new invention can be applied to the manufacture of mobile phone backplanes and aero engine blades, and can even contribute to the aerospace field in the future.

Lu Jian introduced that ceramics are high melting point materials, and it is very difficult to print with 3D, especially the finished products with relatively large printing sizes. To solve this problem, the research team used a mixture of polymers and ceramic nanoparticles to develop a new type of "ceramic ink", and then printed a soft and elastic "ceramic precursor" in 3D. This precursor can be stretched to more than 3 times the length of the original material, and after high temperature treatment, it can produce ceramics with complex shapes.

Lu Jian, who is also the vice president of CityU, has been engaged in 3D printing research for many years. 24 years ago, he led a mechanical systems and parallel engineering laboratory in France, owning the world's early 3D printers. "Parallel engineering means that when we design a product, we take into account both its operation and manufacturing, so 3D printing is a very important tool for us."

4D printing refers to adding a time dimension as the fourth dimension on the basis of traditional 3D printing. Lü Jian said that the advantages of 4D printing include the ability to produce many special structure materials on a large scale, and the ability to produce different geometries through a basic product, with different forces.

The research team printed ceramics with origami structures such as butterflies, the Sydney Grand Theatre, and roses, which were displayed in articles published in journals. "If you want to make art, it can provide artists with a lot of new creative space." Lu Jian said.

In terms of application, Lu Jian said that ceramic 4D printing can be used to manufacture mobile phone backplanes. Especially in the future, mobile phones enter the 5G era, you can avoid the problem of signal shielding, although glass and plastic can achieve the same effect, but the glass is too heavy, and high-end mobile phones rarely use plastic, so ceramics are the right materials.

Another application is in the aviation industry. Lu Jian said that many aviation parts are achieved by 3D printing, and ceramic 4D printing can provide more convenient, cheap and can make more complex parts. Due to the heat-resistant nature of ceramics, he believes that new technologies have the potential to be used in the space industry in the future, such as bringing "ceramic ink" to space and printing the required space equipment parts to reduce the load when the spacecraft is launched.

Lu Jian said that the next step for the research team is to really use the new technology in the industry, as well as to find out the new solution from the perspective of technical research and make it more refined; there is also the expansion of other new materials, they are making superalloys, and there has been some progress. (End)