A Sharp Weapon For Small Yarn "Body Changing" Material Examination

The seemingly inconspicuous small yarn can "transform" into a sharp weapon for sensitive material examination. Through it, the damage of different materials can be detected in real time and nondestructive, making the complex and time-consuming large-scale composite material detection method easy and accurate in the past.

This idea comes from an undergraduate research team in the School of Textile Science and Engineering of Tianjin University of Technology. These young people have been paying attention to the development and application of advanced textile composites for a long time, and have achieved outstanding results in the 13th "Challenge Cup" Chinese College Students Entrepreneurship Plan Competition and the 8th China International "Internet+" College Students Innovation and Entrepreneurship Competition.

Yue Jianing, the team leader, said that rather than winning the prize, he hoped to apply his knowledge to engineering practice, solve the problem of pain points in composite material market testing, and truly "write the paper on the motherland".

After going to university, studying textile engineering, she became very interested in the research of textile composites. Once, when searching for information, she learned that Wu Liwei, an associate professor of the School of Textile Science and Engineering of Tianjin University of Technology, had studied the technology of non-destructive testing for the damage of prefabricated bodies, so she found the teacher to actively participate in the relevant research of the research group.

Wu Liwei told the reporter that textile engineering is not a profession that can only "make clothes" in people's impression. Textile composites have high strength, strong stiffness and low weight, and are now widely used. From satellite antenna to artificial blood vessel; From large equipment to clothes people wear daily, many are closely related to textile technology and composite materials.

Previously, he and Jiang Qian, a researcher in the Composite Materials Research Institute of Tianjin University of Technology and doctoral supervisor, jointly led the structural and functional textile composites research group, and cooperated with Flinders University in Australia to develop a kind of yarn able aggregation induced luminescence material, which can realize real-time sensing and detection of harmful gases and minor damage, with low cost, high sensitivity It can be detected in real time.

After going deep into the front-line research of the enterprise with the instructor, Yue Jianing learned that at present, composite materials are developing rapidly, but there are few NDT methods for composite structural parts. Generally speaking, the industry uses CT testing, ultrasonic testing and other methods, which are faced with difficulties such as high cost, time-consuming and difficult to detect in situ.

She boldly envisions that, based on the above research, can we try to design a kind of yarn flexible sensor for nondestructive testing of large composite components, so that all kinds of material damage can be warned in advance before serious accidents occur to ensure its long-term safe operation?

With the support of the teachers, she and the student team, after several years of exploration, used an emerging nano material preparation technology to prepare a special flexible yarn sensor.

Yue Jianing named this innovative project of nondestructive testing of composite materials "micro fluorescence rapid testing".

"At the technical level, this is one of the more advanced applications of flexible electronic technology, which can be used for in situ nondestructive testing of most composite materials," said Wu Liwei.

Fluorescence mapping enables this flexible sensor to display its characteristics. Through fluorescence irradiation, the invisible stress load information can be visualized. That is to say, with the flexible yarn sensor, the material will display different colors under the conditions of different strength, humidity, etc.

The inspectors hold mobile phones and other terminal devices, and can obtain the load changes of structural parts in the bearing process in real time and intuitively by taking photos, so as to quickly obtain the "physical examination report" of materials, which saves time, labor and money without large-scale testing equipment.

Yue Jianing said that the yarn like shape of this flexible pressure sensor can not only be incorporated into the engineering material preform in the form of reinforcement, but also realize the stress and strain distribution of engineering materials on the millimeter scale, as well as the real-time monitoring of damage and crack growth, and can also predict the service life of materials, "Compared with traditional sensors, this method has low cost and can continuously monitor the whole life cycle of materials. Once problems are found, it can also implement protective maintenance without interrupting service."

Jiang Qian said that in recent years, the structural and functional textile composites team of Tianjin University of Technology has formed a set of research ideas around the structural and functional integration design and preparation technology of textile structural composites, "Pay special attention to the combination of basic research and talent cultivation, the integration of technological innovation and industrial development, constantly strengthen the transformation of research achievements and frontier exploration of textile structural composites, and commit to solving key technical problems."

The team deepens the research and development and preparation of advanced textile composites, continues to enhance the depth of theoretical and practical research on advanced textile composites, and jointly carries out technical research and transformation of production, education and research with China Helicopter Research Institute, China Academy of Launch Vehicle Technology, National University of Defense Technology, Northwestern Polytechnical University, Beijing University of Aeronautics and Astronautics and other units.

The multi-directional braided composite material jointly designed and developed by teachers and students was successfully applied to the Tianjin Science and Technology Major Project "Tianjin" pure solar electric vehicle. As the main load-bearing component, the carbon fiber composite material, which has a weight reduction of more than 30% compared with aluminum alloy, was unveiled at the Tianjin Science and Technology Award Conference and received widespread attention.

The high-temperature resistant thermal seal developed by the team has realized low-cost localization of aircraft parts and won the 2023 China Textile Industry Federation Patent Gold Award. The original textile structural metamaterial has published 14 high-level papers, and is transforming scientific and technological achievements.

The rapid development of new textile materials is also promoting the restructuring and upgrading of the industrial system. Wu Liwei believes that every year, a number of undergraduate and graduate students with innovative spirit participate in the research of emerging fields. "They are the youth power to promote the progress of manufacturing in China."

(Source: China Youth Daily client)