**Beijing, November 8 (Reporter Zhu Min) —" According to the evening news segment of China National Radio, the engine, as the "heart" of aircraft and spacecraft, is a highly complex and precise machine. The manufacturing of just one engine integrates numerous high-tech advancements.

For a long period, China has faced significant challenges in advanced manufacturing sectors such as aircraft engine production. Developed countries like the United States, Japan, and Germany have over 40% of their manufacturing classified as advanced, yet they strictly embargo the export of such equipment to China.

In the face of international blockades, the Xi'an Institute of Optics and Precision Mechanics of the Chinese Academy of Sciences has utilized its ultrafast laser technology to develop industrial femtosecond lasers. This innovation has resolved processing bottlenecks that traditional methods could not achieve, such as ultra-fine, damage-free, and material-selective processing. It provides crucial technological support for strategic emerging industries like spacecraft, large aircraft, and automobiles, marking a breakthrough from zero to one in China's photonics manufacturing technology and equipment.

So, how has this technology played a key role in manufacturing aerospace engines, and what is its significance?

At a manufacturing site belonging to a company affiliated with the Xi'an Institute of Optics and Precision Mechanics, high-precision machinery is in operation. Despite their size, these machines are processing tiny metal blades, which are critical components for aerospace power systems. A researcher from the Photonics Manufacturing Center of the Xi'an Institute explains that the machine is drilling holes in the blades using ultrafast laser technology. He says, "Ultrafast laser, also known as ultrashort-pulse laser, is a powerful cutting tool. Unlike ordinary lasers, this laser vaporizes the material directly without melting it, similar to how ice turns into steam without becoming water first. These blades here have cooling holes that we manufactured. You can feel with your hand that there are no defects, something that traditional processing methods find very difficult to achieve."

This ultrafast laser technology, due to its extremely short duration of action, theoretically generates no heat during processing and is thus referred to as "cold processing." It can resolve processing bottlenecks that traditional methods cannot, such as ultra-fine, damage-free, and material-selective processing, making it the optimal choice for extreme manufacturing in various fields. As extremely precise devices, even a tiny cooling hole in an aerospace engine cannot be taken lightly. Researchers indicate that if the cooling hole is not precise enough, the impact on the engine could be fatal. "On one hand, the engine's lifespan would be shorter, and on the other hand, its thrust would not be sufficient. Why is it called a cooling film? Because cold air enters here and, due to high-speed rotation, it sprays out from this spot, forming a film on the surface. This film isolates the external air, allowing it to withstand higher environmental temperatures, and the higher the environmental temperature it can withstand, the better its ultimate performance will be," the researchers explain.

The Xi'an Institute of Optics and Precision Mechanics has continuously tackled the manufacturing bottlenecks urgently needing resolution for the new generation of blades in the aerospace field and has finally achieved a breakthrough.

The institute, in collaboration with Zhongke Weijing, is leading the CAS Hongguang Special Project "Extreme Fine Manufacturing Equipment for Aero-Engines and Spacecraft." The project has successfully completed its first phase and has moved on to the second phase to accelerate the industrialization of the results. Yang Xiaojun, chairman of Zhongke Weijing and former director of the Photonics Manufacturing Center of the Xi'an Institute, says, "Based on modular, standardized, reliable, and stable design improvements, we have enhanced the performance of ultrafast lasers and ultrafast laser micro-processing equipment. We were the first to develop a series of femtosecond laser high-precision manufacturing equipment ranging from three to seven axes. We have built five pilot production lines for core components and series of equipment and successfully promoted their application in more than 70 representative units in the industry, including Aero-Engine Corporation of China and China Aerospace Science and Industry Corporation. This has resolved the 'neck-bottleneck' problem in the complex micro-structure precision manufacturing of three-dimensional components in engine development and has propelled the independent research and development process of China's engines."

Yang Xiaojun notes that the widespread application of ultrafast lasers has enabled China to keep pace with international advanced levels in the manufacturing of key components for aerospace engines. He says, "In terms of aerospace applications, our team is basically on par with the international advanced level. Of course, they still have some advantages over us in some areas, such as semiconductor packaging, where there is still a gap between us and the international level. However, we also have our own characteristics in some applications and have even surpassed international levels in some performance indicators. For example, in micro-hole processing, we can achieve deeper ultra-deep hole processing than our international counterparts. Overall, we are still at a level of running neck and neck."

Yang Xiaojun points out that the next step for the photonics manufacturing industry of the Xi'an Institute of Optics and Precision Mechanics will focus on solving the "neck-bottleneck" problems in precision manufacturing in the main battlefield of the national economy and major national strategic projects. The strategy will be to "make up for shortcomings and expand the frontier," targeting high-end laser manufacturing and other fields. "We will build the CAS Photonics Manufacturing Engineering Laboratory to fully bridge the gap between research and industry, construct an accelerator for photonics hard-tech industries, and develop new types of photonics manufacturing industries such as high-end laser manufacturing and photonics chip packaging," he says.

Original link:http://m.cnr.cn/news/20201108/t20201108_525323087.html